Delivering Sustainable Buildings: Modern Methods of Construction

Andrew R Walker – Housing & Innovation

Scope

• Energy savings through MMC– Air-tightness– Insulation– Reduced thermal bridging

• Water usage and material savings• Waste savings through MMC

– Off-site construction in factories

• Social & economic contributions• Sustainability encouraging MMC?• Sustainability encouraging innovation?

Sustainability at a high level!

EnvironmentalSocial Economic

Code for Sustainable Homes

Introduced Dec 2007

EnergyWasteWaterMaterialsPollutionHealth and well-beingManagementEcology

Effect of Code on MMC

EnergyWaterMaterialsWaste

Energy

ChallengeU-values 0.35 to 0.15 W/m2KAirtightness to 3 m3 / hr per m2

Renewable technologies integrated into traditional buildThese are only touching the surface!

Building energy efficient buildings using modern methods of construction, EST, pg12

Energy Challenge - Airtightness

Energy Challenge - Airtightness

Energy Challenge - Renewables

Do we have the skills on-site to install these systems?WILL it be easier to train factory workers to install the system….

Better environmentMore control (quality & management)

Environmental Impacts Energy – pros & consFactory• Insulation & services

hidden• Designed to exceed

Part L, thermal and air tightness

• More flexibility• Thinner walls to get

higher U values• Better control of

innovative technologies

Conventional site• Air tightness historically

not as good• On-site application can

cause quality concerns• More material required

to meet lower u-values

Water

• Low use appliances– WC– Washing machine– Dishwasher– Bath– Shower– Taps

• Use of non-mains water– Rainwater– Greywater– Blackwater

Incorporated during fit-out or in pods

Materials

Materials

Environmental impactFavours low embodied energy, low mass, low maintenance materials

Responsible sourcingTimber certification (e.g. FSC, CSA, PEFC)Environmental Management System

Climate ChangeFavours low global warming potential insulants

Material Innovations

Centred mainly on:Reducing solar heat gain

Masonry block MMC panelsPhase changing materials

Reducing heat lossAerogelsVacuum insulated panels

Products using almost 100% recycled content

Waste equation

Assume factories are more efficient than site

More MMC * Greater efficiency = Less Waste

MMC Growth

Figure 1 Growth forecast for MMC permanent buildings

0200400600800

1,0001,2001,4001,6001,8002,000

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

Valu

e £

mill

ions

MMC = Reduction in Waste

Possible reduction in waste through increases in use of MMC

0.0

5.0

10.0

15.0

20.0

25.0

30.0

2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020Ann

ual t

onne

s of

was

te

(mill

ions

)

Reduction in total w aste from construction Reduction w aste sent tolandfill and spread on exempt sites

Market Transformation ProgrammeOpportunities for Waste Reduction Through MMC

Waste Analysis from MMC

• SmartLIFE Project – comparing steel frame, timber frame and masonry– Calibre

• Labour content• Lead times• Value added

– SmartWaste• Resource Efficiency

– WRAP • Comparing masonry on site waste, with,• MMC on site + factory waste

• WRAP Volumetric Project– Comparing:

• normal site based on site waste, with,• MMC on site + factory waste

6-11% reduction in waste

22% reduction in waste

0.00

2.00

4.00

6.00

8.00

10.00

12.00

Site Based Volumetric

Electrical Equipment PlasticsPackaging Canteen / office / adhocMetals InsulationConcrete TimberPlaster / cement Other

EPI

SITE BASED VOLUMETRIC

52% reduction in waste

The social and economic question?

• More houses more factories?• Economic sustainability

– the factory in a region builds the homes for that region– local people work in local factories

• Social sustainability– Look at Honda in Swindon, local community proud to build

the Honda!

• Could happen with MMC factories• Delivering sustainable communities is a

much bigger question…..

Is MMC already delivering?

Stewart Milne

Kingspan

Green House – A Home for the Future?

• Code Level 6• First to be built by volume

housebuilder• MMC masonry walls and SIP

roof• Thermally efficient building

fabric• <1.0 m³/hr/m² air tightness• Mechanical ventilation and

heat recovery • Water efficient appliances and

rainwater recycling for WC• Lifetime Homes & Secured by

Design compliant• Computerised BMS

Is MMC a sustainable construction method?

• YES, but,• Clearly understand what sustainability YOU

want?• We need to understand their constraints

and utilise their strength’s• We need to understand that the composite

nature of MMC enables you to both improve and reduce sustainability

• MMC is between 10 – 60% of the process– remember to integrate it with the complete process

Thank you for listening……