Table of Contents
Unit conversion..........................................................................4
Introduction...............................................................................5
1.Overview of a residential house..............................................6
Loads..............................................................................................................................6
General steps in residential construction.......................................................................7
Section 1 exercises.........................................................................................................9
2. Foundations.........................................................................10
Types of foundations....................................................................................................10
Drainage and water protection....................................................................................11
Section 2 exercises.......................................................................................................13
3.Wood....................................................................................15
Lumber grade stamps..................................................................................................15
Section 3 exercise........................................................................................................ 17
4. Framing................................................................................18
Platform framing..........................................................................................................18
I-Joists.......................................................................................................................... 22
Glulam beams..............................................................................................................22
Section 4 exercises.......................................................................................................24
5. Sheathing.............................................................................26
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Plywood....................................................................................................................... 26
OSB...............................................................................................................................27
Sheathing stamp..........................................................................................................27
Section 5 exercises.......................................................................................................29
6. Exterior wall.........................................................................30
Masonry.......................................................................................................................30
Wood siding.................................................................................................................31
Section 6 exercise........................................................................................................ 33
7. The thermal envelope..........................................................34
R-Value.........................................................................................................................34
Insulation material.......................................................................................................35
Roof ventilation............................................................................................................35
Section 7 exercises.......................................................................................................37
8. Sound...................................................................................38
Transmission of sound.................................................................................................38
STC & IIC.......................................................................................................................39
Section 8 exercises.......................................................................................................41
Annex A - Answers and solutions..............................................42
3
Unit conversion
Length
1 inch (in) = 25.4 mm = 2.54 cm = 0.0254 m1 foot (ft) = 12 inches = 304.8 mm = 30.48 cm = 0.3048m1 mile (mi) = 1 609 m
Area
1 square inch = 6.4516 cm2
1 square foot = 144 in2 = 929 cm2
1 m2 = 10.765 ft2
1 mi2 = 2.59 km2
Volume
1 Gallon, US = 3.785 liters
Temperature
Degrees Fahrenheit (F) = 1.8*(Degrees C + 32)
Mass
1 kg = 1000g1 pound (lb) = 453.6 g = 0.4536 kg
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Introduction
This book was created for the Technical Vocational Education and Training Center at the
Research and Training Institute of Forestry and Wood Industry specifically for the
students in carpentry. This handbook is a complement to their studies and to extend
their knowledge on wood frame residential construction. This book will help them to be
more aware of some functions of different structural elements and to improve their
capability at analysing and thinking for a future project. This book is an educational book
and should not be used as a technical reference for construction.
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1.Overview of a residential house
Firstly we have to understand the basic physic behind a overall house. In the construction we build in the purpose to resist a force - cause and effect.
Loads
In all building construction we'll find the same loads at different levels. We could classified two different class of loads; internal and external. Internal loads are indentified as death or live. The dead load includes loads that are relatively constant over time, including the weight of the structure, and immovable fixtures such as walls, plasterboard or carpet. The roof is also a dead load. Dead loads are also known as permanent or static loads. Building materials are not dead loads until constructed in permanent position. Live loads are temporary, or short duration, or a moving load. These dynamic loads may involve considerations such as impact, vibration, fluids, etc.
Also on every buildings there will be external loads or forces applied by the environment. The external loads could be from the wind, the snow, rain, underground water or even seismic. All of these loads depend on the location of the project, the environment and the climate. This is why it is very important to analysis the environmental factors before each project.
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Illustration 2: Representation of the dead loads, the weight of the material
Illustration 1: Representation of live loads, human weight and fluid for a short amount of time (for example a bath)
General steps in residential construction
Most houses have the same construction steps and usually for framing you will see the platform frame structure method. This section will explain briefly each step of the construction with some visuals.
1. Site clearance and excavation; after choosing the right location for the future house, the site might need some clearance of all obstacles, trees, rocks, etc. After clearance, the excavator will dig for the future foundation and tranches for utilities.
2. Foundation; depending of the type of soil, the foundation will be pour according to the initial design. Further there is a section explaining about different types of foundation and what is necessary to protect it.
3. Framing; now that the foundation is in place the house framing can starts. The platform frame structure consist to start with the first floor framing, after the wall and the second floor, wall, until the desired number of stories. The last part of the
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Illustration 3 : Example of wind and snow load
Illustration 4 : Site clearance and excavation
Illustration 5 : Foundation
framing will be obviously the roof. After the whole structure is completed, the next step is sheathing. After the main framing is done, the interior framing will follow.
4. Plumbing, electricity and ventilation; before closing this inside wall plumbing electricity and ventilation pipes have to be installed all around the house. This technical part is not covered in this book.
5. Insulation; after all the utilities are installed around the house it is time to insulate it.
6. Exterior walls; depending of what type of exterior wall is used, the construction of the exterior wall might starts at different time of the construction but the framing and sheathing have to be finished before the installation.
7. Finishing works; this part includes the flooring, drywalls, painting, housing appliances, painting, etc.
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Illustration 6 : Framing
Section 1 exercises
For all the exercises you can find the answers in the annex at the end of this book.
Exercise 1
For all this loads tell what type of load are they associated with, death, live or environmental.
1. Second floor framing2. Empty bath3. Family having dinner4. Wind5. Bath filled with water6. Couch7. Snow on the roof8. Oven
Exercise 2
Place in order the following steps of a residential construction.
1. Foundation2. Plumbing and electricity3. Site clearance and excavation4. Insulation5. Framing6. Finishing works
Exercise 3
Explain the platform framing structure method.
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2. Foundations
Foundation is a very important structure of a house. It is the base of a house where all the weights of the building are transferred to it. The foundation has to be built on solid ground to assure longevity of it and the building that it supports. The main functions of a foundation is to transfer the loads of the building to the ground and anchor the building against environmental stress.
Types of foundations
For residential construction there is 3 basic foundation types; full basement, crawl space and slab on grade. The next illustration shows the design of these type of foundations.
Illustration 7 : Basic foundation, from left to right, full basement, crawl space and slab on grade
One the most common footing for residential construction is the continuous or strip footing. It consists to be spread footing which is provided for a load bearing wall for the full basement and crawl space foundation. As the Illustration 8 shows, the strip footing is only the bottom part of the foundation and after the walls is connected to the footing with steel bars. This type of foundation is also called T-shaped foundation.
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Illustration 7 : Continuous or strip footing
Another type of foundation used is the individual footing. This footing will usually support column. Sometimes houses have open crawl space like the illustration 9 and isolated footing is the one used for this kind of construction. It is also convenient when the house need to be raise up because of environmental issues. As you can see on the illustration below the column is connected to the footing with steel bars.
The last common foundation in the residential construction is the slab on grade. This type of foundation is the easiest of all, the fastest to construct and the lowest on cost. This type is more used in warmer countries. Here in Mongolia, footings as to be below the frozen ground where the ground is stable. Because when a ground freeze it affects the stability of the ground and over time could move the original position of the foundation and cause structural damage to the house.
Drainage and water protection
Excessive moisture in a basement or crawl space gives rise to some problems. The wood structure can be infected by a fungus and over time, destroyed by dry rot (type of mushroom). Also not evacuating the excessive water from either the rain or from the ground can affect the stability of the soil and move the original location of the footing. This could result with some fractures on your outside walls.
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Illustration 8 : Isolated footing Illustration 9 : Open crawl space
Illustration 10 : Slab on grade
Footing drains have two functions. They draw down the groundwater level to below the basements walls and floor, and they collect and drain away water that seeps down through the backfill from rain and melting snow. Before filling around the foundation a drain as to be installed at the same level of the footer. The next illustration shows a perimeter drain system. Adding to the drain the foundation wall as to be protected against the water also with a water barrier. There is multiple products on the market to protect against water.
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Illustration 11 : Perimeter drain system
Section 2 exercises
Exercise 1
What are the two main functions of a foundation?
Exercise 2
Associate the type of foundation with the picture.
1. 2.
3.
A. Isolated footingB. Continuous footingC. Slab on grade
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Exercise 3
Associate the type of foundation with the appropriate footing.
1. Full basement A. Strip footing2. Slab on grade B. Isolated footing3. Open crawl space C. Slab
Exercise 4
What are the two main functions of a drain around a foundation?
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3.Wood
Wood is one of nature's most beautiful building material. This material offers diverse options for constructors. Here's a quit review of its main advantages and disadvantages.
Pros
Responsibly sourced wood is the only renewable building material available The production and processing of wood uses much less energy than most other
building materials Wood helps to tackle climate change by storing carbon from the atmosphere,
the carbon remains stored in the wood for the life of the product. Wood is a durable material if well maintained it can last for hundreds of years Wood is structurally very strong, compared with steel and concrete wood has a
better weight strength ratio than both of them Wood itself is a natural insulator and soundproofing material Wood construction is fast and efficient It can adapts to different geometric shapes
Cons
Highly flammable, this is the main concern of all wooden construction Cannot support or resist heavy load like concrete or steel does Wood is a natural material so it is vulnerable to some insects and to fungi who
could affects wood strength and cause deterioration
Lumber grade stamps
A grade stamp assures the lumber customer that the piece of lumber carrying the stamp meets the minimum standard for the stated purpose. Some stamps certify strength for use in framing, whereas others certify appearance for use in millwork. There is a wide array of grade stamps from certified agencies but all of them should have the same model. Reading grade stamps is simple and the next illustration will show how to.
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16
Mill number where the lumber was manufactured
Grade:SEL.STG.= Select Structural1 = No.12 = No.23 = No. 3CONST. = ConstructionSTAND. = StandardUTIL. = UtilitySTUD = Stud
Certified agency under whose rules the lumber was graded
Species may be a single species or a group of species having similar characteristics
Moisture content (MC) at the time of surfacing:S-GRN = MC 20% or moreS-DRY = MC 19% or lessMC 15 = MC 15% or less
Illustration 12 : Typical lumber grade stamp
Section 3 exercise
Exercise 1
Explain each numbers associated to a part of the following lumber stamp.
Exercise 2
Which of these two stamps indicate a better grade of the wood?
A. B.
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4. Framing
To make a human analogy, the frame of a building is its skeleton. To assure that this skeleton is strong enough, the weight that the frame will support need to be specified. The weight consist of the loads explained in section 1. This section overview the general framing of a house and explain the main parts of the framing.
Platform framing
These days one method of framing is used mostly in the construction field and it is called platform framing. A platform consisting of all the elements of a floor. After the foundation is completed the first floor is constructed. After completion of the first-story walls, the second platform is built identical to the first as if the first-story walls were the foundation.
Illustration 13 : Platform framing steps
Floor framing consists of a repetition of joist supported on both extremities by either a wall or beam. The following illustration list all the main components of a floor frame.
18Illustration 14 : Example of a floor framing
The span that a joist can support depends on many factors. Once again the loads that will be applied on a specific floor as to be determined. After the design of your floor will depends on the size, the grade of the wood, and the span between each support. There is many available floor span table available online to help with floor design. Here's a small example.
Example 1
For example, the size of the joist on site is 38x170 mm and the span between the wall and the beam is 2.3m.
Illustration 15 : Example of a span table
You start looking at the line with the same wood dimension and look for the equal or the closest lower span on this line. For 38x170 it is 2.69m and the 600mm above the column means the distance between each joist that you have to respect for construction.
This is just an example of a span table, there is different span tables for all species of wood. It is important to look at the grade of the wood because a wood graded No. 1 is more stronger than a grade No.2 and it will affect the distance between joist.
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The same theory applies to wall framing. The next illustration shows the main components of a typical wall frame.
The distance between the wall studs depends on the size, grade and species of wood. You can find the same span table showed on the illustration 15 but for wall studs instead.
Roof framing is the final step in the house framing. The next illustration shows a common roof framing and its elements.
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Illustration 16 : Typical wall framing
Illustration 17 : Roof framing
But this last type of framing is becoming less used. With the decreasing availability of large structural lumber, trusses offer cost savings in both roofs and floors. The reason they can do so, in spite of an added cost of fabrication, is that the lengths of lumber subjected to bending stress are broken into smaller sections. Indeed, these days roof framing is usually built with trusses. This already assemble piece is quicker to install and offers many options of design for the costumer. Here's a common design of a truss and with some different design available on the market.
Illustration 18 : Components of a common truss
Illustration 19 : Different type of roof trusses
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I-Joists
The I-Joist is an engineered wood structural member, designed for residential floor framing. I-joists are comprised of top and bottom flanges, which resist bending, united with webs, which provide outstanding shear resistance. The robust combination of structural characteristics results in a versatile, economical framing member that is easy to install in residential and light commercial projects. Here's some of the I-joist characteristics:
Flanges are either sawn lumber or structural composite lumber. Top and bottom flanges are of the same type and grade material.
Webs consist of wood structural panels, consisting of exterior plywood or OSB (oriented strand board).
It can support a higher load on a longer span than conventional joist, but you need to refer to the appropriate span table before installation.
Illustration 20 : I-Joist
Glulam beams
When load or span requirements are too great to allow use of commonly available dimension lumber or timbers, lumbers glulam beams can solve the problem. They offer inexpensive alternatives to steel. Pound for pound, glulam beams are stronger than
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steel. Glulam beams consist of a number a layers glued together to form the appropriate beam. It Increased design values, improved product performance, and cost competitiveness make glulam the superior choice for projects from simple beams and headers in residential construction.
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Illustration 21 : Glulam beams
Section 4 exercises
Exercise 1
Place in chronological order the following step of the platform framing construction.
1. First wall framing2. Second floor framing3. Roof framing4. First floor framing5. Second wall framing
Exercise 2
Here's a the dimension of the first floor of a house.
You want to buy 38x147 joist for this framing. Before going to the shop you want to know how many joist you need to buy and you have this span table with you.
How many joist should you buy at the shop?
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7.5m
2,75m
Exercise 3
Associate the right element with the illustration.
Bottom plate Band joist Subflooring Stud Joist Double plate
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5. Sheathing
If the frame is the building's skeleton, then the sheathing is its skin. Sheathing functions to enclose the building in an airtight barrier, to strengthen its studs, joists, and rafters by tying them together, to brace the building against racking (twisting) under wind and seismic forces, and to provide a base for flooring, siding, and roofing. There is two main sheathing panels plywood and OSB. Even if both are considered to have the same strength and durability, there is some differences to consider.
Plywood
Plywood is a versatile building material made from thin layers, or ``plies`` of wood veneer glued together. It is a very durable material that provides an excellent foundation for building, so it is used in a variety of projects. But, as with any building material, it has both advantages and disadvantages that should be understood before use.
AdvantagesThe layers that make up plywood are intentionally glued together at alternating right angles. This is what gives it both strength and durability. This cross-graining also reduces the chances of the wood spliting whennailing at the edges, and it makes the wood resistant to warping, craking, and twisting. the way plywood is made also ensures a consistent strength across the entire length of the wood. In addition to its strength, plywood can resist to water for short amount of time, is less expensive than similar boards made of full wood species, which makes it an ideal construction planking material.
DisadvantagesEven if plywood can resistwater for a short period a time, if exposed to leaks over time, plywood becomes heavy when wet and can be damage of it.
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Illustration 22: Plywood
2
1
3
OSB
Oriented strand board (OSB) is a type of engineered lumber similar to particle board. It is formed by adding adhesives and then compressing layers of wood strands in specific orientations.
AdvantagesFirstly OSB is much cheaper than plywood because the thin strands used in its manufacture are lower in price. Also, the manufacturing process of OSB results in less wastage, because most of the wood is used up. OSB is considered more environmentally friendly tan plywood for the same reason. Unlike plywood, which is usually manufactured from selected types of wood, OSB can be made from most trees.
DisadvantagesOne of the main problem with OSB is that it is susceptible to moisture damage is a cut edge is exposed to water.
Sheathing stamp
Sheathing panel are used for flooring, the roof and walls. But there is a stamp also for sheathing like regular wood to be sure the right panel is installed to resist the load or the environmental exposure. Here's an example of a panel stamp.
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Illustration 23 : OSB
Illustration 24 : Panel stamp
There is three main characteristics to notice from the stamp.
1. Panel rating: It indicates the max performance of the panel and it where is should be used.
2. Span rating: If the panel is used for flooring or roofing you have to make sure the panel span rating respect the span between the joist. For example the 32/16 means the max span for roof is 32 inches between each support and 16 inches between floor joist.
3. Durability rating: This one explains the bond classification relates to moisture resistance of the glue bond, and thus to structural integrity of the panel. There is three classifications;
Exterior panels are suitable for repeated wetting and redrying or long-term exposure.
Exposure 1 panels are intended to resist the effects of moisture during construction and for exterior use where not directly exposed to water.
Interior panels are manufactured with interior glue and are intended for interior uses only.
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Section 5 exercises
Exercise 1
Describe the 2 functions of sheathing.
Exercise 2
Associate the characteristic with the right panel (plywood or OSB)
A. Can resist to water for a short amount of timeB. Can be fabric from different species of treesC. It is more expensive than the other panelD. It is more environmental friendly panel
Exercise 3
You finished the framing of your second floor. The distance between each joist is 18 inches. You go at the shop and they only have one type of panel with this following stamp.
Should you buy this panel? Explain your answer.
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6. Exterior wall
This section will only cover two types of exterior wall, masonry and wood siding. In reality there is many types of exterior wall but these two are the most common one in residential construction.
Masonry
Masonry constitutes man's oldest building material. Remnants of masonry structures more than 3,000 years old still exist. Chief among masonry materials are concrete blocks, and mortar, which is the glue used to fasten solid masonry units together. Concrete blocks are usually used for foundation wall in the residential construction. The concrete blocks are connected to each other with rebar and to the foundation. Also at intersecting walls there should have connector to assure the stability between the walls. The next illustration shows a typical concrete blocks wall construction.
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Illustration 25 : Typical concrete blocks construction
A second whole class of masonry consists of brick. As with concrete blocks, there is a wide range of standards brick sizes. More than with concrete blocks, brick is used in a variety of wall positions and patterns to achieve architectural designs. Despite its obvious strength in compression, brick veneer over a wood frame wall functions as a low-maintenance exterior finish only and not as a structural element. This is because brick and wood expand and contract with moisture and temperature differently and so cannot be rigidly bonded in the vertical plane. Because a thin brick wall has little bending strength against wind and earthquake, however, it must be tied to the stronger wood stud wall horizontally. The illustrations below show the connecting wall ties and detail the recommended flashing at wall bottoms.
Wood siding
Aside from decoration and a dual role as structural sheathing, the function of wood siding is to keep the structure and interior of a building dry. Water penetrates siding in one or more of three ways:
As bulk flowing downward under the force of gravity
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Illustration 26: Flashing at bottom of brick wall
As rain water driven horizontally by the pressure of wind As rain water drawn upward by capillarity (surface tension acting in small
spaces).
The three problems are prevented in three very different ways:
Gravity - by flashing at horizontal junctures of buildings surfaces and materials Wind - by venting the back side of siding to equalize air pressures Capillarity - by eliminating capillary-sized gaps between siding courses, using
round head nails or wedges.
The illustration below shows examples of each technique.
Illustration 27 : Siding moisture control
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Section 6 exercise
Exercise 1
Associate the materials with the right elements.
1. Weep openings2. Water barrier3. Insulation4. Wall tie5. Air space6. Foundation7. Sheathing
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7. The thermal envelope
The thermal envelope is the set of building surfaces separating the conditioned (heated and cooled) interior of a building from the outdoors. To be maximally effective, the thermal envelope must meet the following conditions:
Every surface must be insulated to the R-value (thermal resistance) appropriate to the climate.
The entire envelope must be sealed on its warm side by a vapor barrier. The envelope must be relatively air tight.
R-Value
Most building constructions consider of a number of component parts, each with differing thickness and R-value. The R-value is a measure of thermal resistance for materials (such as insulation) and assemblies of materials (such as walls and floors) in the building and construction industry. It gives an indication of how quickly they will loss heat (their thermal resistance). The higher the value of R, the better the thermal performance and heat resistance of the material or assembly, and the slower any heat loss. To calculate the R-value of a wall, roof or floor you just need the sum all the R-value of the different layers according to their thickness. Here's an example how to calculate it.
Example 2
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You have this type of design for a future exterior wall and you have the R-value of all different materials in the next table.
R-value(Total) = R-value(brick) + R-value(air) + R-value(insulation#1) + R-value(insulation#2) + R-value(gypsum)
R-value(Total) = 5 + 6 + 7*2 + 8*3 + 2*0,5 = 50
Insulation material
There is a multiple of insulation material available on the market. Insulation are categorized by its composition (natural or synthetic) and form (batts, blankets, loose-fill, spray foam and panels). This handbook won't provide comparative between different product because there is so many on the market and all of them have pros, and cons.
Roof ventilation
The main problem if your top ceiling is not well insulated and the attic not well ventilated is a problem of water and ice. The illustration 28 shows an ice dam in action. The attic floor is well insulated, but so is the roof, due to the insulating action of the snow. With insufficient attic ventilation, the attic temperature falls somewhere that of the living space below and the air outside. Water from melting snow flows downward toward the eaves. The roofing at the eaves is closer to ambient air temperature, however, so the melt water refreezes. As the ice builds up, it creates a dam for further melt water. If the backed-up melt water extends beyond the coverage of the roofing material, the water penetrates the roofing. The illustration also shows the most
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common way to prevent this problem: continuous soffit for a proper ventilation. That means to have an air flow in the attic so an entry and an exit at the top of your roof.
Illustration 28 : Ice dam prevention & example of a soffit
The first important thing to do before looking at the design of your attic is to have a vapor barrier on the last ceiling to stop the vapor going in the attic and causes future problem.
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Section 7 exercises
Exercise 1
Calculate the R-value total of the wall with the following data:
Exercise 2
Which of this factors listed cause the ice dam problem on a roof?
a) Snow on the roofb) Good insulation between the attic and the interior of the housec) Bad ventilation of the atticd) Type of heating system of the housee) Bad insulation between the attic and the interior of the house
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8. Sound
The quality of sound in our homes has a great effect on our comfort. When we play music or engage in conversation we want to hear clearly and hear well. On the other hand, when other family member is playing music in another part of the house or the neighbors having a celebration we don't want to hear at all. Sound intensity is measure in decibels (db). To have a better understanding of the decibel measure here's a list of different sound source with their decibel level.
Transmission of sound
Sound can be transmitted through a wall, floor, or ceiling in three ways:
Leaks or openings allow sound to propagate as though the wall, floor, or ceiling didn't exist
Airborne sounds set a building surface into vibration, it is then carried though the rigidly attached wall studs to the opposite surface, causing it in turn to reradiate to the other side, much like the two heads of drum
Impact of an object falling on a floor causes the ceiling attached to the same floor joists to radiate sound to the room below.
Walls and floor-ceiling are rated by their abilities to reduce sound transmission, the next table shows the effect on hearing of various levels of sound reduction between spaces.
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STC & IIC
The rating for walls, floors or ceiling is different and more complex than the R-value. Walls are rated by sound transmission class (STC), floor-ceilings are rated by both STC and impact insulation class (IIC), a measure of the noise transmitted when objects are dropped on the floor above. The following table shows recommended STC and IIC for residential construction.
STC IIC Effect on hearing
45 - Wall separating living space from living space or public space, such as corridor
50 - Wall separating living space from commercial space or high-noise service space such as boiler or mechanical room
45 45 Floor-ceiling separating living space from living space or public space, such as corridor
50 50 Floor-ceiling separating living space from commercial space or high-noise service space
The recommendation for a residential construction is at least 45 STC and 45 IIC.
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Each material as a specific STC but to know the total STC of a wall it is not the summation of all STC of each layers of material. For a builder or a customer we cannot calculate the STC of a wall, floor or ceiling it is only in laboratory with special equipments that measure frequency of sound from each side of a separation. But the STC and IIC rating can be increased by three principal techniques:
1. Increasing the mass of the wall (installing a second layer of drywall, for example).
2. Decoupling the opposing surfaces ( by staggering the studs, for example).3. Including sound-absorbing materials (filling stud cavities with fibrous insulation,
for example).
The next illustration shows example of wall with their STC value. There is various combinations possible for soundproofing a wall, floor or ceiling.
Illustration 29 : Example of soundproofing wall
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Section 8 exercises
Exercise 1
What are the three ways sound is transmitted between wall, ceiling or floor?
Exercise 2
What are the three ways to increase wall, ceiling or floor soundproofing?
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Annex A - Answers and solutions
Section 1
Exercise 11.Death 2.Death 3.Live 4.Environmental 5.Live 6.Death 7.Environmental 8.DeathExercise 23,1,5,2,4,6Exercise 3It starts with the first floor framing, after the wall and the second floor, wall, until the desired number of stories. The last part of the framing will be obviously the roof. After the whole structure is completed, the next step is sheathing.
Section 2
Exercise 1The main functions of a foundation is to transfer the loads of the building to the ground and anchor the building against environmental stress.Exercise 21.C 2.A 3.BExercise 31.A 2.C 3.BExercise 4They draw down the groundwater level to below the basements walls and floor, and they collect and drain away water that seeps down through the backfill from rain and melting snow.
Section 3
Exercise 11: Certified agency name2: Mill number3: Lumber grade; select structural4: Species of wood
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5: Moisture content, S-Dry 19% or less
Exercise 2B, because A is grade 2 and B is select structural
Section 4
Exercise 14,1,2,5,3Exercise 2The span is 2.75 meters and the dimension of the wood is 38x147
The closest lower span is 2.71m and the distance between each joist as to be 450mm.7.5m/0.45m = 16.66 joists so you will need to buy 17 joists.Exercise 3A. Stud B. Subflooring C. Joist D. Bottom plate E. Band joist F. Double plate
Section 5
Exercise 1Sheathing functions to enclose the building in an airtight barrier, to strengthen its studs, joists, and rafters by tying them together, to brace the building against racking (twisting) under wind and seismic forces, and to provide a base for flooring, siding, and roofing.Exercise 2Plywood; A,COSB; B,DExercise 3
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No, because the distance between your joists is 18 inches and the max distance between supports the panel can resist is 16 inches. So you should not buy this panel.
Section 6
Exercise 1A.5 B.7 C.3 D.2 E.4 F.1 G.6
Section 7
Exercise 1R-value(Total) = R-value(brick) + R-value(air) + R-value(insulation#1) + R-value(insulation#2) + R-value(gypsum)R-value(total) = 4 + 3 + 5*2 + 4*3 +3*0.5 = 30.5Exercise 2A;C;E
Section 8
Exercise 1Leaks or openings; airborne sounds that cause vibration; impactExercise 2Increasing the mass; decoupling the opposing surfaces; including sound-absorbing materials
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