McMaster Green Roof Proposal

Executive Summary

The Ontario Public Interest Research Group of McMaster (a student funded/student directed organization working on issues of human rights, the environment, and social justice) has been working on creating a green roof plan for the McMaster Student centre terrace this year as part of an initiative to promote the benefits of green roofs and to show their potential for success on campus.

There are many spaces on campus where green roofs could be successfully applied to improve the appearance of the area and to provide many cost-‐saving and aesthetic benefits. Some of these benefits include amenity space, supporting biodiversity, lowering energy demands, increasing the lifespan of the roof's waterproofing membrane, reducing airborne pollutants, reducing noise, reducing runoff from storm water, reducing the heat island effect, and providing LEED building credits.

The McMaster Student Centre was chosen for this project because of its availability, accessibility, high visibility, and high energy demands. These factors make it an ideal location to showcase the potential of green roofs and to act as a demonstration as to how they might be implemented on other roofs on campus. This location currently acts as a lunch spot for many staff and students at McMaster as well as being a place where some campus wedding parties go for refreshments and to socialize. Currently the space is sparsely decorated and only has a few small potted plants to add colour to the space. As building codes permit much higher occupancy per square meter and higher loading than is currently being utilized the space is an ideal location for adding larger plants and green roof material. The design being proposed for this space complements the ability for the space to hold large events and gatherings while also adding a great amount of aesthetic and environmental value to the terrace.

The design maximizes the potential of the terrace by incorporating well layered plants of varying heights at the sides of the location. This gives the feeling of being within a relaxing green space to those dining

on the terrace as well as providing a visually appealing backdrop for conversations and photos. Green roofs also improve air quality, lower the roof temperature during summer, and improve the insulation value of the roofing they are installed on.

The plants chosen for the design are well suited to enduring hot, dry, and sunny environments with minimal maintenance and minimal watering requirements. For periods with very little rainfall the green roof design being proposed is to be connected to a nearby water line in the student centre which would be used as part of an irrigation system (which comes standard with many of the green roof packages being considered for the design).

Table of Contents Executive Summary ..................................................................................................................................... 2

Table of Figures ........................................................................................................................................... 4

Definitions and Terms.................................................................................................................................. 5

History of Green Roofs and Green Spaces at McMaster ............................................................................. 6

Objectives .................................................................................................................................................... 8

Proposed Location ....................................................................................................................................... 9

Proposed Design & Layout......................................................................................................................... 11

Rain Water Collection & Water Connections ............................................................................................ 12

Drainage Systems ...................................................................................................................................... 14

Green Roof Materials ................................................................................................................................ 15

Plant Types and Plant Positioning Recommended .................................................................................... 16

Project Costs and Business Plan ................................................................................................................ 19

Plant Costs ............................................................................................................................................. 19

Green Roof Materials ............................................................................................................................ 19

Planters.................................................................................................................................................. 20

Water Rerouting .................................................................................................................................... 21

Water Collection.................................................................................................................................... 21

Benefits of Green Roofing ......................................................................................................................... 22

Amenity Space ....................................................................................................................................... 22

Support of Biodiversity .......................................................................................................................... 23

Lowered Energy Demands and Longer Roof Lifespan ........................................................................... 23

Reducing Airborne Pollutants and Improving Air Quality...................................................................... 24

Noise Reduction and Protection............................................................................................................ 27

Stormwater Management ..................................................................................................................... 28

Urban Heat Island Effect........................................................................................................................ 30

LEED Building Credits ............................................................................................................................. 31

Codes and Standards ................................................................................................................................. 32

Fire Code Requirements ........................................................................................................................ 32

Building Code Requirements ................................................................................................................. 32

Building Permit Application ................................................................................................................... 32

Bibliography............................................................................................................................................... 33

Table of Figures Figure 1 -‐ McMaster Univesity Panorama, from the Southwest (Cruickshank, 2008)................................. 6

Figure 2 -‐ Green roof Implemented in the Arts Quad.................................................................................. 7 Figure 3 -‐ Class of '54 Garden at McMaster, located between Hamilton Hall and the Faculty Club ........... 7 Figure 4 -‐ MDCL Roof as it is now (viewed from the 4th story stairs)........................................................... 8

Figure 5 -‐ MDCL Roof as it could be (viewed from the 4th story stairs) ....................................................... 8 Figure 6 -‐ McMaster Student Centre as viewed from the East parking lot to show the terrace ................. 9 Figure 7 -‐ Student Centre Terrace ............................................................................................................. 10

Figure 8 -‐ Proposed green roof design viewed from above and the Southeast ........................................ 11 Figure 9 -‐ 4th Floor Drainage Pipe ............................................................................................................. 12 Figure 10 -‐ Handytank 1000L Rain Storage (Green Venture, 2010)........................................................... 12

Figure 11 – Enlarged section of the Student Centre plumbing diagram with a few possible water line locations highlighted ................................................................................................................................. 13 Figure 13 -‐ An example of the drains on the student centre terrace ........................................................ 14

Figure 12 -‐ Architectural drawing of roof heights for the student centre terrace with drainage and green roof overlay ............................................................................................................................................... 14 Figure 14 – Vegetative roof assembly (Bioroof, 2009) .............................................................................. 15

Figure 15 -‐ Structural loading capacity diagram for the terrace (Atkinson Engineering Inc., 2000).......... 16 Figure 16 -‐ Ripe Prickly Pear Cactus (zoofari, 2008) .................................................................................. 16 Figure 17 -‐ Firewheel flower (Poon, 2007) ................................................................................................ 17

Figure 18 -‐ New Jersey Tea (Nebraska Forest Service, 2008) ................................................................... 17 Figure 20 -‐ Preliminary plant positioning diagram .................................................................................... 18

Figure 19 -‐ Indian Grass (DePauw University, 2010).................................................................................. 17 Figure 22 -‐ Mayne 20 In. Square Farifield Patio Planter in Clay (Home Depot, 2010) ............................... 20 Figure 21 -‐ Southern Patio 24 In. Diamante Black Walnut Finish (Home Depot, 2010) ............................ 20

Figure 24 -‐ Monarch butterfly perched on flower and gathering nectar (Monarch Butterfly Information, 2010).......................................................................................................................................................... 23 Figure 25 Air Quality Index Graph Created from Air Quality Ontario Data 2010 as of Aug. 29 ................. 24

Figure 26 -‐ Parking lots on campus at McMaster as shown in the Campus Master Plan (Urban Strategies Inc., 2008) .................................................................................................................................................. 25 Figure 27 -‐ Percentage Breakdown of CO2 Emissions by Source for McMaster University as of 2007

(Zerofootprint, 2009)................................................................................................................................. 26 Figure 28 -‐ 10 Buildings with Highest Total Emissions as of 2007 (Zerofootprint, 2009) .......................... 26 Figure 29 -‐ Cootes Paradise highlighted on a map of McMaster's campus in the Campus Master Plan

(Urban Strategies Inc., 2008) ..................................................................................................................... 28

Figure 30 -‐ A diagram showing the many different sources of runoff and their path (NC Department of Environment and Natural Resources, 2009).............................................................................................. 29

Figure 31 -‐ A Graph showing the temperature at different levels of urbanization in order to demonstrate the effect of plants on temperature reduction (Interlock, 2009).............................................................. 30

Definitions and Terms

Extensive Green Roof – A green roof typically composed of smaller plants such as sedum which require less than 12in of soil and requires very little maintenance

Engineered Media – A type of soil compound used in green roof projects due to requirements of low

weight, high water retention, and high drainage rates. This can include volcanic ash, peat, perlite, vermiculite, and many other blends of materials as needed for each specific project.

Intensive Green Roof – A green roof typically composed of larger plants which requires a depth of soil over 12in and typically requires watering and maintenance

LEED -‐ Leadership in Energy and Environmental Design

MUSC -‐ McMaster University Student Centre

OPIRG – Ontario Public Interest Research Group. The membership of OPIRG Provincial is comprised of eleven autonomous, non-profit, university student-funded and directed organizations that conduct research, education, and action on social and environmental justice issues on behalf of the Ontario public.

RGB – Royal Botanical Gardens

Semi Intensive Green Roof – A green roof with a soil depth between 12-‐16in that is suitable for extensive plants as well as small shrubs, bushes and grasses

Figure 1 -‐ McMaster Univesity Panorama, from the Southwest (Cruickshank, 2008)

History of Green Roofs and Green Spaces at McMaster

McMaster University has a proud history of deep respect for green spaces and the environment in the

Hamilton community. Its stunning location adjacent to Cootes Paradise, one of the largest remaining wetland areas on Lake Ontario, makes it stand out in the greater educational community as a place where education physically meets the environment. This is reflected by its diverse environmental

programs, including the Institute of Environment and Health, Earth Sciences, and Engineering and Society. McMaster is also connected to many surrounding natural areas by trail networks that run through protected lands owned by the Royal Botanical Gardens (RBG). As such, it is crucial that

McMaster maintain its status as both a responsible steward of its natural surroundings and a worthy partner of RBG by continuing its proud history of supporting environmentally focused policies.

Currently, McMaster has implemented a sizable green roof in the arts quad just outside of the student centre which has been planted with tall grasses. Although not easily noticed as a green roof due to its

location being at ground level, it still provides many of the benefits associated with green roofs to the basement levels beneath it. This is an excellent use of the space which will help to keep stormwater

runoff under control during heavier storms while providing a beautiful spot for lunches and breaks between classes. The green roof design contained in this proposal is made to advance the

Figure 2 -‐ Green roof Implemented in the Arts Quad

goals stated during the implementation of McMaster’s first green roof and to take the green roof

program to new heights.

Besides its green roof, McMaster’s campus also boasts many gardens and natural spaces which add tremendously to the image of campus. One particular example of this is the class of ’54 garden located just behind Hamilton Hall:

Figure 3 -‐ Class of '54 Garden at McMaster, located between Hamilton Hall and the Faculty Club

This garden has a broad range of flowers and grasses which give it great visual depth and detail, helping

to make this location stand out from its surroundings. This spot is often visited during weddings as a site to see and is an ideal backdrop for pictures.

By adding green spaces to its campus, McMaster has created a peaceful and natural atmosphere which improves the image of campus aesthetically, but also provides many other forms of benefits (eg social,

psychological, environmental, and medical) to be discussed in later sections.

Potential sites for designating more green spaces on campus are becoming harder and harder to come by as more development takes place and new buildings, parking lots, or pathways spring up each year. So, in considering how to add green space to McMaster in the future one of the best places to look is on

the rooftops. Adding colourful grasses, sedum, flowers, and shrubs to rooftop spaces can change a dreary and dull space into a natural space which blends in with McMaster’s green surroundings and contributes towards the University’s environmental goals. For example, consider how a blanket of small

sedum plants could add colour and style to the Michael Degroote Centre for Learning and Discovery; what a complement for the waterfall and plant life already contained within the building!

Figure 4 -‐ MDCL Roof as it is now (viewed from the 4th story stairs)

Figure 5 -‐ MDCL Roof as it could be (viewed from the 4th story stairs)

The potential for green roofs is enormous at McMaster, as most buildings on campus have only a minimal slope: such roofs are ideal for green roof installation. Given McMaster’s potential, this proposal

is designed to showcase the many benefits green roofs can offer McMaster as well as to present a design plan for implementing a green roof on the third floor terrace of the MUSC (McMaster University Student Centre).

Objectives

The primary objectives of this proposal are to:

1) Facilitate the implementation of a green roof on the 3rd floor student centre terrace (as outlined in the design section of this proposal),

2) Demonstrate the many benefits that green roofs provide, including improving staff and student health, facilitating cost reduction efforts, and improving energy efficiency on campus, and

3) Promote the use of green roof technology in future renovation and building projects at McMaster

University.

This document will show compliance of the design with all necessary regulatory codes, besides highlighting key features that make the chosen location optimal for implementation. It will also show how green roofs can help to realize University goals as stated in the McMaster Master Plan towards

achieving a cleaner, greener, and more livable campus.

Proposed Location

There are many spaces on campus where green roofs could be successfully implemented to improve not only their appearances but also to provide many cost-‐saving benefits (as will be described in later

sections). The location chosen for this project was determined based on comparing different buildings’ potential for the greatest visual impact, educational impact, and staff/student interaction.

Figure 6 -‐ McMaster Student Centre as viewed from the East parking lot to show the terrace

The site chosen for this project is the McMaster Student Centre, specifically the third floor terrace,

because of its availability, accessibility, high visibility, and the building’s (currently) high rate of energy consumption. These factors make it an ideal location to showcase and physically demonstrate the potential of green roofs on campus. We hope that the success of this installation will inspire other

green roof implementations at McMaster.

This location currently acts as a lunch spot for many staff and students at McMaster as well as being a place where wedding parties, who have rented other areas of the Student Centre, inevitably go for refreshments and conversation. Currently the space is sparsely decorated with only has a few small

potted plants. Since building codes permit much higher occupancy per square meter and higher loading bearing than is currently being utilized the space is an ideal location for adding larger plants and green roof medium.

As is shown in the picture to the right (Figure 7 -‐ Student Centre Terrace), the space is

currently covered with large cement tiles which are evenly spaced throughout the terrace. These tiles are resting on top of a

waterproof layer which is quite durable and able to withstand large amounts of weight on top of it (up to 2.8kN/m2, which far

exceeds the needs of the green roof design proposal). This is beneficial to the project because this layer will not have to be

replaced with other materials and therefore will substantially lower the costs of the project.

Current expectations for the space, as

described by Student Centre Manager Lori Diamond, require the space to be able to accommodate 10-‐12 tables and also be able

to seat up to 120 people within the necessary regulatory parameters. As such, one of the main constraints facing this

design is optimizing the usability of the space by tailoring the design according to

staff/student needs and welfare.

The location has no direct access to any readily available water source so, in order to

maintain water levels during droughts and heat waves, additional water sources would have to be found

or created for the space. This will be discussed further in the section on “Water Sources”.

Figure 7 -‐ Student Centre Terrace

Proposed Design & Layout

The proposed green roof design incorporates a large variety of native flowers, grasses, and shrubs that would create a year-‐round green space on the terrace. As seen below, the design accommodates 15

tables and allows for clear sight lines of the proposed gardens from each of the doors and windows along the side of the building.

Figure 8 -‐ Proposed green roof design viewed from above and the Southeast

Smaller plants were chosen for in front of the southern skylights in order to prevent any possible

shadowing of the skylight and to complement the role of the skylights in the overall design of the terrace space.

The curvilinear contours of the green roof design employed at both ends wrap around the four adjacent tables on the terrace, thus creating attractive lunch nooks. Their side locations provide a desirable

background atmosphere for meetings, lunches, and conversations, as well as providing a cooling effect

during the summer due to the reflective, absorptive and evaporative properties of the plants which give off less heat than the concrete tiles currently in use.

The rectangular gardens, located between the ends

and opposite the doors, considerably lower the cost of the overall design by reducing the quantity of perimeter material required, while simultaneously

providing a central location for educational displays that describe the importance of planting native species. These displays demonstrate McMaster’s

commitment to smart environmental effort to the public and promote future projects at McMaster and within the Greater Hamilton Community. The

multiplicity of plants used in the design creates interesting visual rhythms and allows the viewer to see multiple types of plants from each angle and

during each season. From the vantage points of the doorways and terrace the showy flowers of the smaller plants can be seen in spring and early fall. These flowering plants are located in front of several species of golden, red and green grasses which frame the former with a natural backdrop. The taller

grasses and shrubs used at the edges of the gardens are also visible from the perspectives of the parking lots or walking paths on the grounds in front of the student centre and provide attractive sightlines from those perspectives year round.

Rain Water Collection & Water Connections

Although green roofs are very low maintenance and can typically

survive drought conditions it is prudent to have secondary sources of water available for the plants in times of extreme drought, intense

heat, and especially during their initial planting. A suitable option for

a secondary source would be the deployment of rain barrels that hold

rain water from the 4th floor roof and store it until such time that it is needed.

Permission has been obtained to divert water from the 4th floor drainage pipe into rain barrels and the amount of rainwater gathered

from this should be sufficient to water all of the gardens. The highest level of watering that could possibly be needed would be the water saturation point of the soil, and this outside figure gives us an

Figure 10 -‐ Handytank 1000L Rain Storage (Green Venture, 2010)

Figure 9 -‐ 4th Floor Drainage Pipe

estimate of the water reserve required for this space. For a 20-‐40cm thick growing media (a fair estimate for what will be used in this proposal) studies have shown moisture retention of between 10-‐

15cm (Venneri, 2003). The water needs of the plants species chosen for this design are much less than the saturation point and can be expected to be around 10%-‐20% of the water saturation of the soil. This would mean that the green roof could need 1000L-‐2000L of water in order to keep the plants properly

maintained during a short dry period. The use of rain barrels allows the space to be maintained without imposing significant water needs to the infrastructure of the student centre. Price estimates for rain

barrels were obtained from

Green Venture; barrels 1000L in size sell for $350 each. Because rain barrels are dependent solely

on rainfall, it is recommended that a water connection be installed on the terrace in case of

a longer dry period, and also to sustain the green roof during the first few months of growth while

the plants’ root sytems become established. There are many points where the current

plumbing infrastructure could be modified to have a connection to

the green roof system. Some of the nearest water connections have been highlighted on the

diagram below.

Figure 11 – Enlarged section of the Student Centre plumbing diagram with a few possible water line locations highlighted

Drainage Systems Although a convenient water source is not yet available for the site, the drainage system in place is well designed and can easily accommodate any excess rain that falls on the terrace. As shown

in the diagram to the left, the roof drains to six central drainage locations which are positioned at even intervals in a North-‐South alignment.

In considering which parts of the roof to cover with green roof

gardens it is easiest and most cost efficient to choose locations which do not cover any of the current drainage locations because of the extra cost associated with purchasing special covers. As

such the design was overlaid with this diagram in order to avoid all drainage points.

The slope provided by the current roof structure is sufficient for proper drainage as water flows through the drainage layer of the

green roof material; these will prevent excess water buildup on the waterproofing layer of the green roof.

Figure 13 -‐ An example of the drains on the student centre terrace

Figure 12 -‐ Architectural drawing of roof heights for the student centre terrace with drainage and green roof overlay

Green Roof Materials The soil used for this design would be 10cm deep for the majority of flowering plants and grasses with raised planters used to allow for a 15-‐20cm depth for shrubs and larger plants. This allows the use of

larger plants without necessitating the large costs that uniformly higher soil depths throughout the roof would require.

Figure 14 – Vegetative roof assembly (Bioroof, 2009)

The drawing shown above (Figure 14 – Vegetative roof assembly (Bioroof, 2009)) shows the different

layers present in a typical green roof design. In the case of the terrace, the insulating layer and roof waterproofing layers are already in place and could potentially be removed in order to reduce costs, but it is recommended that a secondary waterproofing layer be placed on top of the root-‐stopping layer in

order to have full waterproofing warranty for the green roof and to eliminate the need for a third party to assess the waterproofing of the proposed location.

This diagram also shows that the saturated weight of the green roof supplies and a light vegetative layer would be approximately 25lbs/ft2 (122.06kg/m2 or 1.22kN/m2) which is less than half the rated load for

the terrace in all locations (2.8kN/m2) as long as no significant portion of the weight is placed on the metal barrier surrounding the terrace.

Figure 15 -‐ Structural loading capacity diagram for the terrace (Atkinson Engineering Inc., 2000)

Plant Types and Plant Positioning Recommended

In selecting plant species for implementation in the green roof, our overriding concern was to make sure that all species were local to southern Ontario. This concern reflects the educational objective we hope to achieve in bringing this green roof to McMaster: all garden areas will have didactic panels indicating

the names of all plants in the garden, their role in sustaining local biodiversity, and their medicinal/therapeutic value. In so doing, we hope to prove, by way of example, that one need not sacrifice aesthetic appeal, utility, or low maintenance costs, in the planting of a native garden; meeting

this educational objective would have the effect of encouraging anyone who visits the garden to plant local species in their own.

Roof sites for gardens present challenging design constraints for would-‐be green roof gardeners. A high degree of aridity, shallow soil depth, limited area, plant costs and project-‐budget, as well as the high

aesthetic standards of the public, are all important factors that must be taken into account in the design process – we had to find native species that could fit all of the above criteria. Fortunately, the Hamilton

area boasts many such species, due to the pre-‐settlement prevalence of the oak-‐savannah and dune biomes, remnants of which survive to this day, and are even extant adjacent to campus. In order to create maximum aesthetic dynamism, plants were selected from amongst four orders: ground cover,

wildflowers, grasses, and shrubs. Species were selected for their flowering times, drought tolerance, commercial availability, and soil-‐depth requirements. Here follows four examples in more detail, one for each of the plant categories represented in the garden design:

Prickly Pear Cactus (ground cover): Ground cover is usually planted at the

front of a garden since these plants grow low to the ground and will either

Figure 16 -‐ Ripe Prickly Pear Cactus (zoofari, 2008)

be shaded out if planted further in, or at the least, will be obstructed from vision. While Prickly Pear Cactus is not technically native to the Hamilton region, it is local to southern Ontario, and its aesthetic

impact within the garden is well worth pushing the definition of ‘local’ a little – besides, it is nearly impossible to verify the presence/absence of Prickly Pear populations prior to settlement times, so for all we know, populations may have been present before we came here. Certainly, the green roof

provides excellent conditions for cacti growth, and the bright yellow flowers and fleshy green limbs provide lunch-‐goers with the mental suggestion of eating in a more southerly location: while at lunch, why not go on a little imaginary vacation! The Prickly Pear is also edible for humans, and its flowers

attract butterflies and hummingbirds.

Firewheel (wildflower): Wildflowers are planted just behind ground cover plants since they are slightly taller in comparison, but themselves are slightly shorter than both shrubs and grasses. Wildflowers are famous for

their brilliant colors and shapes and are the main providers of aesthetic appeal in the garden. Firewheel, also known as Indian Blanket, is a particularly striking plant due to its brilliant yellow and red petals. It grows

in dense clumps and has been used in the design of our garden as a focal point amongst other, less showy flowers such as Jerusalem Artichoke and Milkweed. The roots may be used in tea or a poultice.

New Jersey Tea (shrub): In contrast to wildflowers, shrubs have a

substantial and solid form in comparison to their more delicate and intricate counterparts. Shrubs have mainly been employed in this garden as the opaque backdrops against which the brilliancies of the wildflowers

stand out, although this is not always the case since many species of shrub can hold their own, aesthetically speaking, even next to Firewheel (e.g.

Northern Bush Honeysuckle in the spring)! The flowers of the New Jersey Tea are as delicate as any wildflower’s, and possess a restrained beauty all

their own. This species is extremely drought tolerant and remains green throughout the growing season and is the host plant of the rare mottled duskywing butterfly. True to its name, the dried leaves of the

plant make an excellent tasting tea.

Indian Grass (grass): Grasses are the tallest of the four orders of plants selected for planting in the green roof. Since the soil depth is too shallow for trees, grasses are ideal candidates for the final and highest visual layer in a

lunch-‐goer’s sightlines. Indian Grass has been employed here as a taller grass that, in conjunction with slightly shorter grasses such as Little

Bluestem, creates visually interesting alternating rhythms in height as one looks across the gardens. This

local species is frequently used as an ornamental since its large nodding head and golden yellow color lend it a strong, handsome appearance.

Figure 17 -‐ Firewheel flower (Poon, 2007)

Figure 18 -‐ New Jersey Tea (Nebraska Forest Service, 2008)

Figure 19 -‐ Indian Grass (DePauw University, 2010)

Figure 20 -‐ Preliminary plant positioning diagram

Project Costs and Business Plan

The costs associated with the implementation of this design can be broken down into five categories:

plant costs, green roof materials, planters, water rerouting costs, and water collection. The total cost for the project is estimated to be $28,260 (before donations and discounts are applied). This figure will be reduced considerably by discounts and donations, but provides an upper estimate for the project

expenses.

Plant Costs Plant costs vary dramatically from plant to plant and the number of plants needed must be estimated based on the average size of the plants picked for the design. A number of the plants chosen for this

design are very common and will be donated from members of the OPIRG community. Other less common plants are to be purchased at McMaster suppliers in order to take advantage of discounts. A first estimate of the cost for plants is based on data gathered from Terra greenhouses as an indicator of

retail prices in the local area for the type of plants that are to be purchased. Local suppliers were used for providing estimates because of OPIRG McMaster’s desire to support local businesses and keep transportation distances to a minimum.

Grasses were found to cost approximately $5 to $10 per square foot of plant material. They occupy

approximately 15m2(161ft2) of space, which puts the grasses cost between $800 and $1600 at retail prices. The flowers used for this design were more expensive and were between $10 and $15 per square foot. The garden design uses a great deal of flowering plants (50m2 or 538ft2) but will have a

small amount of space around each plant which puts the retail costs of this plant type between $4300 and $5000. The shrubs used in the design were the most cost efficient plant (planter and increased need for growing medium aside) and were priced at approximately $5 per square foot. The total cost

for the 15m2(161ft2) of shrubs is estimated at $800. This brings the total cost of plants in this design, at retail pricing, to between $5900 and $7400. This number will be significantly reduced (likely by more than half) once all discounts and donations are obtained, but these will be arranged closer to the plant

date, so as to guarantee pricing and availability at the time.

Green Roof Materials The layers needed for waterproofing, drainage, root protection, soil, and water retention together have been priced by Bioroof as a potential supplier. The total cost stated for these layers is estimated to be $270/m2 ($25/ft2) which results in the following costs:

Location Area Cost North Curved Section 18m2 $4860 Terrace Sections 30m2 $8100 South Curved Section 33m2 $8910 Total: 81m2 $21870

Planters The costs of planters used in this design are estimated based on a few designs of planters being

considered for the project. The current design for the green roof calls for approximately 10 planters to be placed within the gardens in order to allow for the planting of larger shrubs without needing a large soil depth throughout the roof. For these locations, only a small portion of the top of the planter will be

seen and as such the planter’s appearance will not take away from the overall appeal of the design. A few different planter options are available:

Picture

Planter Type

Figure 22 -‐ Mayne 20 In. Square Farifield Patio Planter in Clay (Home Depot, 2010)

Price $49.99 $129.00 Warranty 10 year warranty 15 year warranty

Figure 21 -‐ Southern Patio 24 In. Diamante Black Walnut Finish (Home Depot, 2010)

OPIRG will be contacting Home Depot and other home building stores about discounts and donations of planters at a later time so these costs should be used only as a temporary estimate. The total amount

needed to fund all of the planters at full retail price would be $500.

Water Rerouting The cost of rerouting water lines to the terrace is minimal in terms of parts and supplies needed but may require numerous hours of work by staff at McMaster. This is one aspect of the project which will be asked of McMaster to supply since the university can accomplish this at any point throughout the year

and has staff on hand for such purposes.

Water Collection The cost of the irrigation system has been included in the price for the green roof materials, but the cost of rain barrels to supplement this has not. The cost of rain barrels was stated earlier as being approximately $350 per 1000L, and it is recommended that one be purchased as a test to see if they

work for the space. The presence of the rain barrel also encourages the public to consider rain barrels as a sustainable alternative to conventional water sources.

Benefits of Green Roofing

Amenity Space

The addition of green space on campus does not have to take potential development space away; green spaces can be a functional use of rooftops: they open up possibilities for the space that typical roofs do not realize. By creating a green space on rooftops, harsh and bleak landscapes characteristic of most

rooftops on campus are minimized and replaced with natural landscapes. On accessible roofs with railings, this type of roofing can make the space into an ideal location for a break instead of just being another useless heat island. McMaster’s efforts in this regard could create positive psychological

benefits for all those who use (or even just see) the space (Ken Willis, Dr Liesl Osman, and CJC Consulting, 2005). Such ideal spaces let students, staff and faculty know that McMaster cares about their health, welfare, and comfort.

In our design, the use of green spaces complements table placement by giving users a more natural

setting for their event and can provide a larger degree of privacy; there are also ideal podium sites in front of each of the two rectangular gardens (e.g. for wedding functions, speeches, and presentations).

Figure 23 -‐ An overhead view of the third floor terrace green roof proposal highlighting podium sites for group events

The natural setting contributes health benefits and lowered stress levels; green spaces are also attributed with increasing the productivity of staff and students who use the space (Susan Barton,

2009).

Support of Biodiversity

One of the most intriguing aspects of green roofs compared to traditional roofing is that a green roof is alive – it is living in itself, and supports a wide variety of life within it. The living roof can provide

both food and shelter to a large number of birds, insects, and other animals depending on the design and plant selection. The use of butterfly grasses, and flowering perennials can attract a wide variety

of butterflies, bees and other insects while the larger plants and

shrubs provide sheltered areas for birds. The proposed green roof employs a large number of both host and nectar plants for butterflies. The vibrant colours of the butterflies complement the roster of native

species planted, and provide an additional visual treat for those dining on the terrace. By choosing only native plant species for use in the green roof design, we eliminate the risk of introducing invasive alien species while simultaneously creating a reservoir of seeds that sustain local native species.

Lowered Energy Demands and Longer Roof Lifespan

Given the rising costs of energy it is economically crucial to find ways to reduce energy consumption in order to maintain costs at manageable levels. The implementation of a green roof has been shown to

significantly increase the insulation value for the roof and also to reduce the wear that ultraviolet light has on roofing membranes. This results in a lower energy bill due to lowered heating and cooling needs and significantly longer lifespan for roofing (Gail Lawlor, 2006).

To give a more concrete example of how green roofs can prevent energy losses it is easiest to show the

insulation value provided by the green roof. The amount of insulation provided by the green roof varies greatly depending on the type of soil, membrane and plants used, but studies have shown that a 20cm layer of growing medium and a thick layer of plants can be approximated as having a combined

insulating value of RSI 0.14 (R20) (Venneri, 2003). This is a significant amount of insulation and is comparable to 12.7 cm of glass fiber insulation or 9.14 cm of urethane rigid foam (Cengel, 2007).

Another study showing the benefits of green roofs in the winter has shown that a layer of 30cm of growing medium with plants can keep the roofing materials from going below 0oC even when outdoor

temperatures are below -‐20oC (Venneri, 2003). This effect significantly improves the lifespan of the roof since the roof is precluded from such dramatic extremes of expansion and contraction, thus reducing the chance of crack formation due to seasonal exposure. The soil layer also significantly reduces the

physical effect of erosive forces and of frost and ice formation during the winter (Newton, 1993).

Figure 24 -‐ Monarch butterfly perched on flower and gathering nectar (Monarch Butterfly Information, 2010)

Because the green roof dramatically increases the insulation value of the roof, it also lowers the amount of energy used for heating or cooling that the building requires in the process of maintaining desired

temperatures.

Reducing Airborne Pollutants and Improving Air Quality

Air pollution is a serious issue at McMaster because of its proximity to major transportation routes (e.g. Main Street, Cootes Drive) and many nearby parking lots used by commuters travelling to campus. As a result, McMaster is at risk of smog buildup during spring, summer, and fall. This can have serious effects

on the air quality in the area and can lead to health complications in those with respiratory problems. As is shown in the graph below, McMaster (approximated by the west Hamilton study) has air quality issues nearly 16% of the year. This has resulted in smog warnings in the past and this will likely continue

in the next few years as traffic is unlikely to change substantially in this area.

Figure 25 Air Quality Index Graph Created from Air Quality Ontario Data 2010 as of Aug. 29

0

5

10

15

20

25

30

35

40

45

50

1 9 17

25

33

41

49

57

65

73

81

89

97

105

113

121

129

137

145

153

161

169

177

185

193

201

209

217

225

233

241

249

Air Qua

lity Inde

x

Day

Air Quality Index for Western Hamilton 2010

This can be summarized as follows:

6.35% Very Good Air Quality 77.97% Good Air Quality 15.68% Moderate Air Quality – This can result in breathing difficulty for those with asthma and other breathing conditions

Specific areas of McMaster also face air quality concerns due to their proximity to large parking lots and high levels of traffic. The risk of compromised air quality on campus due to adjacent parking lots and traffic is expected to increase as more parking is opened up in accordance with the latest version of the

McMaster Master Plan (Urban Strategies Inc., 2008). Having green roofs near these locations would be a great benefit to air quality on campus due to their capacity to absorb pollution caused by vehicles. The proposed green roof site detailed earlier in this document (i.e. the third floor student centre terrace) is

an excellent location for reducing air pollution originating in the parking lot on the east side of the student centre.

Figure 26 -‐ Parking lots on campus at McMaster as shown in the Campus Master Plan (Urban Strategies Inc., 2008)

Aside from direct effects on air quality, the reduction in heating and cooling demands discussed earlier also results in a significant reduction of greenhouse gases produced. As shown in the graph below, the

most significant source of pollution at McMaster is due to heating and cooling needs of buildings on campus. By reducing the amount of energy needed to maintain proper temperatures the amount of pollution produced will decrease as well.

Figure 27 -‐ Percentage Breakdown of CO2 Emissions by Source for McMaster University as of 2007 (Zerofootprint, 2009)

This can be shown in more detail for individual buildings on campus in the following chart. It lists the top 10 emission generating buildings on campus are listed as follows:

Figure 28 -‐ 10 Buildings with Highest Total Emissions as of 2007 (Zerofootprint, 2009)

As shown in the chart above, a large portion of the emissions each building produces is a direct a result

of regulative heating and cooling processes used throughout the year. The specific location chosen for this proposal, the McMaster University Student Centre, is one of the bigger buildings on this list and has a substantial amount of room for improvement in regards to the amount of pollution generated (1235

tons). Other locations mentioned in the chart above should be considered for future implementation of green roofing on campus, but are outside the scope of this proposal. This chart (Figure 28 -‐ 10 Buildings with Highest Total Emissions as of 2007 (Zerofootprint, 2009)) was created as part of the Zerofootprint™

program which McMaster has been using for several years as part of its commitment to reducing the environmental foot print of buildings and services associated with McMaster University. By using green

roofs to reduce the pollution caused by buildings on campus, McMaster would be well on its way to achieving a “zero footprint” And would further advance its image as a responsible neighbor to the

surrounding natural and urban (Westdale and Dundas) communities.

Noise Reduction and Protection

McMaster is world renowned for its dedication to excellence in education, providing top notch facilities for lectures, laboratories, and libraries. Many of these spaces have been carefully engineered to reduce external noise while facilitating acoustics; this has the net effect of allowing students to better hear the

lecturer in classrooms. Due to the importance of carefully controlling noise levels inside buildings on campus, the excellent sound insulation benefits of green roofs should be noted. The growing medium of typical green roofs can be designed to block low frequencies of sound, and the plants themselves are

capable of blocking higher frequencies. Studies testing the effect of the growing medium alone have been shown to reduce sound levels by 40db (Kuhn, 2009).

Stormwater Management

Adding greenroofs to building tops is an effective means of retaining water during periods of heavy rainfall. This prevents flooding, the overtaxing of aging combined sewer systems, and the runoff of chemicals and waste into the water supply. This is an extremely important issue for McMaster due to its

location in the middle of ecologically sensitive lands and a vulnerable watershed, not to mention the value such measures have for preventing the potential economic and aesthetic nightmares that flooding causes.

The Campus Master Plan has stressed that “The University will work to manage stormwater on campus, through measures designed to reduce runoff from building roofs, streets and paved areas, and to improve the quality of the stormwater runoff, “ as well as requiring “all new building projects and renovations to meet the University’s Sustainable Building policy and to include measures to conserve resources in both construction and ongoing maintenance, using native species and naturalized planting in landscape projects adjacent to natural areas, and employing measures to reduce waste, and stormwater runoff.” (Urban Strategies Inc., 2008) McMaster is located beside Cootes Paradise – one of the largest remaining wetlands on Lake Ontario. These wetlands are very

sensitive to oil, heavy metals, road salt, waste and other debris which

can be swept from the streets, parking lots, and overtaxed sewer systems

directly into the watershed during storms.

One of the best ways to prevent runoff is to lower the amount of impervious

surface area on campus so that water is absorbed where it falls instead of

flowing along the dirty surfaces into our lakes, rivers, and sewers. By deploying green roofs on McMaster’s buildings, the amount of runoff the sewer

systems have to handle can be decreased significantly, thereby alleviating the risk to the ecosystem and unprotected riverbanks.

The economic value of reduced risk of flooding and lowered sewer needs is typically difficult to calculate, but at least some of this value is evident in the costs associated with the refurbishment of

aging sewer systems. The city of Hamilton recently published the results of a study done by an

Figure 29 -‐ Cootes Paradise highlighted on a map of McMaster's campus in the Campus Master Plan (Urban Strategies Inc., 2008)

independent research group hired for this very purpose (i.e. to find the most appropriate way to pay for the replacement of aging sewer systems) this spring and is currently debating the implementation of

their recommendations. The final recommendations were as follows:

“Charges for non-‐residential properties would be assessed based on actual measured impervious area on a parcel by parcel basis, at a rate of $18.40 per month per SFU (i.e., per 301 m2 of impervious area).” (AECOM, 2010) The implementation of the proposed project would save

McMaster approximately $60 per year for this reason alone (if the recommendations are followed). Though admittedly,

this seems small, over the course of the 20+ years this project is designed to last it would mean a savings well exceeding $1000 (based on a converted area of

approximately 84m2).

One of the less talked about benefits of minimizing runoff for a property through green roofs is the potential to reduce the chance (and magnitude) of flooding and water issues on

it. By reducing the amount of water which is to be absorbed by the ground around the building, the earth there is able to take a larger amount of rainfall before it becomes fully

saturated and starts to pool water. This has posed problems on campus in several areas in the past and could be reduced through the use of this type of technique.

In order to better explain the magnitude of effect that green

roofs can have in reducing the amount of water flowing off of the roof and preventing these stormwater problems, studies were found to quantify their effect. It has been

shown in studies that the addition of a 20-‐40cm layer of engineered soil can retain between 70-‐100% of rain water that falls onto it during normally occurring summer storms

and between 40-‐50% of rain during winter storms when the substrate is frozen (Stephen W. Peck, 1999). For a large roofed surface this can result in a very significant amount of

water being used to beautify the roof (by watering the plants on the green roof) instead of causing problems to the urban and natural environment.

Figure 30 -‐ A diagram showing the many different sources of runoff and their path (NC Department of Environment and Natural Resources, 2009)

Urban Heat Island Effect

This is one of the most prevalent reasons for the implementation of green roofs in an urban

area. The heat island effect can raise the temperature of an urban area by up to 10oC (Gail Lawlor, 2006) which causes a dramatic

increase in ground level ozone formation and is one of the leading factors causing respiratory illness in urban areas (Cheung). The added heat

also strains air conditioning systems, and thus increases the amount of energy used for maintaining proper temperatures during the

summer. One of the most effective ways of combating the urban heat island effect is by using plants to reduce the temperature gain. Plants are able to do this because during photosynthesis, plants transpire, which releases water to be evaporated and cools down the plant and its surroundings. A report in New

York which outlined the best practices for reducing the heat island effect concluded that “a combined strategy, which maximizes the amount of vegetation in New York by planting trees along streets and in

open spaces and building green roofs offers more potential cooling than any one individual strategy.” (Peck, 2008)

This makes green roofs an ideal means of reducing summer temperatures on the terrace of the student centre, thus creating a much more comfortable environment for lunches, dinners, and socializing during

hot weather.

Additionally, research has shown that during summer months, each reduction of 1oC would save approximately 4% off the average demand for electricity (Peck, 2008). The reduction in cooling needs can dramatically lower cooling costs (which are significant for large buildings) and, as corollary, also

potentially save a great deal of money during the development of a new building on campus or the refurbishment of an older building, because cooling systems can be reduced in size according to the offsetting effect of the green roof.

Figure 31 -‐ A Graph showing the temperature at different levels of urbanization in order to demonstrate the effect of plants on temperature reduction (Interlock, 2009)

LEED Building Credits

McMaster University has a meaningful history of green building policies on campus: The university has followed the LEED (Leadership in Energy and Environmental Design) building system (since 2005) during construction and renovations of university buildings. It has strived to obtain a LEED silver rating on all of

its new building projects and to improve the environmental rating of buildings it renovates. Incorporating green roofs into building and renovation efforts can dramatically increase the number of LEED points available and help McMaster to achieve the high levels of environmental stewardship it

wants. Here are the points which can be awarded to buildings for their use of green roofs (Canada Green Building Council, 2008):

Stormwater Management: Rate and Quantity (Sustainable Sites Credit # 6.1) If a roof has less than 50% impervious surface (if 50% or more of the roof has green roofing) then it can qualify for 1 credit for

managing stormwater runoff as long as the green roof is substantial enough to reduce discharge by 25% or more or reduces the runoff more than the pre-‐development runoff.

Heat Island Effect: Roof (Sustainable Sites Credit #7.2) If a roof has over 50% of its surface covered by green roof material it can significantly reduce the temperature of the rooftop and qualifies the building for 1 credit in heat island effect reduction.

Water Efficient Landscaping: (Water Efficiency Credit #3) By using drought resistant plants as part of the green roof design you can earn up to 5 points towards LEED certification. The initial point is given for achieving 50% water needs reduction and an additional point is given for every 12.5% water needs reduction achieved in the green roof plant choices.

Optimize Energy Performance: (Energy and Atmosphere Credit #1) The ability for green roofs to lower the roof temperature during the summer and provide insulation during the winter can significantly reduce energy needs for the building it is used on. This credit is based upon the total energy reduced for the entire building, and as such the use of green roofs greatly increases the ability of the building to meet these goals. Depending on the amount of energy reduced the energy savings can result in earning between 1 and 18 points.

Innovation in Design: (Credit #1.1, 1.2, 1.3, or 1.4) Green roofs provide many benefits to the building’s

environmental standing which may not all be encapsulated by the previous points. Because of this, there is an additional point which can be awarded to the building for green roofs as an innovative design feature of the building.

Codes and Standards All of these sections are to be completed following discussions and revisions as requested by the McMaster building specialists.

Fire Code Requirements The design meets fire code requirements. Current requirements for the space with 120 people have

been met within code in the case of adopting the full-‐scale design outlined in the proposal.

Building Code Requirements Currently being worked on by employees of McMaster.

Building Permit Application As it is a modification of existing roofing materials a building permit and the approval of a structural engineer are required for the project. An application is currently being processed and is planned to be done shortly.

Bibliography AECOM. (2010). Hamilton Stormwater Rate Feasibility Study. Hamilton: City of Hamilton.

Atkinson Engineering Inc. (2000, Jan 10). 51S106 -‐ High Roof Framing Plans. Hamilton, Ontario, Canada.

Bioroof. (2009). Vegetative roof parapet detail . Retrieved June 28, 2010, from Bioroof:

http://www.bioroof.com/systems/systemdetails/eco_details/ECOSYST-‐VRA.pdf

Canada Green Building Council. (2008, November). LEED 2009 for Existing Buildings. Retrieved July 4, 2010, from Canada Green Building Council: http://www.usgbc.org/ShowFile.aspx?DocumentID=7245

Cengel, Y. A. (2007). Heat and Mass Transfer A Practical Approach Third Edition. New York, NY: McGraw-‐Hill.

Cheung, I. (n.d.). EXTREME HEAT, GROUND LEVEL OZONE CONCENTRATION, AND THE URBAN. Retrieved

July 4, 2010, from Clean Air Partnership: http://www.cleanairpartnership.org/pdf/finalpaper_cheung.pdf

Cruickshank, P. (2008, June 13). McMaster Univesity Panorama, from the Southwest. Retrieved June 2, 2010, from Peter Cruickshank's Photostream:

http://www.flickr.com/photos/petercruickshank/2575695559/

DePauw University. (2010). Indian Grass. Greencastle, Illinois, United States.

Fenwick, P. (2005, March 19). Sunroot flowers.

Gail Lawlor, B. A. (2006). Green Roofs A Resource Manual for Munincipal Policy Makers. Canada Mortgage and Housing Corperation.

Green Venture. (2010). Handytank 1000L Slimline Water Saving System. Retrieved June 7, 2010, from Green Venture: http://www.greenventure.ca/handytank-‐1000l-‐slimline-‐water-‐saving-‐system

Hilty, J. (2010, June 18).

Home Depot. (2010). Mayne 20in Square Fairfield Patio Planter in Clay. Retrieved June 30, 2010, from

Home Depot: http://www.homedepot.ca/webapp/wcs/stores/servlet/CatalogSearchResultView?D=978089&Ntt=978089&catalogId=10051&langId=-‐

15&storeId=10051&Dx=mode+matchallpartial&Ntx=mode+matchall&N=0&Ntk=P_PartNumber

Home Depot. (2010). Sothern Patio 24 In. Diamante Black Walnut Finish. Retrieved June 30, 2010, from Home Depot:

http://www.homedepot.ca/webapp/wcs/stores/servlet/CatalogSearchResultView?D=909649&Ntt=9096

49&catalogId=10051&langId=-‐15&storeId=10051&Dx=mode+matchallpartial&Ntx=mode+matchall&N=0&Ntk=P_PartNumber

Interlock. (2009, February 23). Green Roofing -‐ Alberta's Best Roof. Retrieved July 4, 2010, from Interlock

Lifetime Roofing Systems: http://www.albertasbestroof.com/green-‐roof

Ken Willis, Dr Liesl Osman, and CJC Consulting. (2005, October). Economic Benefits of Accessible Greenspaces for Physical and Mental Health: Scoping Study. Retrieved July 5, 2010, from http://www.forestry.gov.uk/pdf/fchealth10-‐2final.pdf/$file/fchealth10-‐2final.pdf

Kuhn, S. P. (2009). Design Guidelines for Green Roofs. Toronto: CMHC.

Monarch Butterfly Information. (2010). Monarch Butterfly Migration. Retrieved July 5, 2010, from

Monarch Butterflies Information and Monarch Butterfly Facts: http://monarch-‐butterfly.info/Migration.html

NC Department of Environment and Natural Resources. (2009, November 2). Retrieved July 4, 2010, from Durham County Government: http://www.co.durham.nc.us/departments/swcd/Stormwater.html

Nebraska Forest Service. (2008). New Jersey Tea. Lincoln, Nebraska, United States.

Newton, J. J. (1993). Building Green: A Guide to Using Plants on Roofs Walls and Pavements. London:

The London Ecology Unit.

Peck, S. W. (2008). Award Winning Green Roof Designs. Atglen, PA: Schiffer Publishing Ltd.

Poon, W.-‐C. (2007, May 28). Firewheel or Indian Blanket with a Spider at the back. Austin, Texas, USA.

Stephen W. Peck, C. C. (1999). Greenbacks from Greenroofs: Forging a New Industry in Canada. Toronto: Canada Mortgage and Housing Corporation.

Susan Barton, R. P. (2009, January 31). Human Benefits of Green Spaces. Retrieved July 5, 2010, from Cooperative Extension -‐ University of Deleware College of Agriculture and Natural Resources:

http://ag.udel.edu/udbg/sl/humanwellness/Human_Benefits.pdf

Urban Strategies Inc. (2008). McMaster Master Plan 2002 -‐ Updated Nov. 2008. Hamilton: MMM Group.

Venneri, R. (2003). Green Practices and Technologies for Sustainable Communities. Hamilton: McMaster University.

Zerofootprint. (2009). 2007 Greenhouse Gas Emissions Inventory. Hamilton: McMaster University.

zoofari. (2008, May 27). Prickly Pear 5half. United States.

McMaster Green Roof Proposal

Documents

Transcript of McMaster Green Roof Proposal