colin powell gcp architecture slides

Domestic Energy Efficiency: Where now?

Colin Powell BA(Hons) DipArch Msc RIBA

gcp : architecture : energy : sustainable design

gcparchitecture : energy : sustainable design

gcp are one of the leading housing

design practices in the region with a

specialist knowledge in the design of

low energy buildings

Our pragmatic approach and

experience supports our clients in

developing realistic and deliverable

solutions

Our collaborative experience,

working in partnership with

contractors, gives us an

understanding of the challenges for

delivery of high performance

buildings in a competitive

construction market

i n t r o d u c t i o n

Sidford Road, Bedminster : 71 Homes for Knightstone Housing

2016 Zero Carbon Standard & AECB Silver Standard

gcp Chartered Architects


The Government ‘Housing Standards

Review’ – concluded in 2015 -

changed the landscape for standards

relating to housing design

Most significantly the Code for

Sustainable Homes was withdrawn

with some elements of the Code

incorporated into revised Building

Regulations

In addition the National Planning

Policy Framework was modified to

restrict powers of Local Planning

Authorities to require higher (than

building regulations) energy efficiency

standards

Following the May 2015 general

election - Government announced it

did not intend to proceed with the

2016 Zero Carbon Standard or

Allowable Solutions mechanisms

Energy Performance of Buildings

Directive (EPBD) (currently) includes

requirements for ‘cost optimal’

reviews of minimum energy

performance standards – the next

review should take place in 2017

EPBD also requires that all new

buildings (in member states) should

be ‘Nearly Zero Energy’ by 2020

b a c k g r o u n d


Planning Authorities in the local area

are illustrative of the confusion the

recent changes to regulatory

standards have generated

Many authorities were slowly moving

towards adoption of energy or carbon

reduction standards commonly

expressed through target

requirements based on the Code for

Sustainable Homes or ‘Merton Rule’

standards for inclusion of renewables

The changes to National Planning

Policy have left many of these

processes in limbo, or being rejected

at the inspection stage

Bristol City Council Policy BCS14

requires 20% reduction in carbon

emissions through use of renewables

North Somerset Policy CS2 requires

10% reduction in energy through use

of renewables

B&NES are currently seeking

approval for a policy requiring 10%

energy through on-site renewables

Merton-style policy

Other authorities in the region have

‘soft’ policies requiring statements on

sustainability or energy efficiency

l o c a l l a n d s c a p e


The 2017 Housing White Paper focuses on delivery of numbers and the economic challenges for home ownership – particularly for first time buyers

but:

“The equivalent of the population of Glastonbury will die this winter from being in fuel poverty”(calculated from Govt statistics for ‘excess winter

deaths’ and WHO calculation)

Over 10% of UK households cannot afford to keep their house warm

Energy providers are predicting steep rises in energy prices in spring this year

a r e w e t a k i n g o u r e ye s o f f t h e b a l l ?

DECC – monthly retail price indices

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Fuel price indices in the domestic sector in real terms 1992 to 2012

Coal and smokelessfuels

Electricity

Gas


B.Regs Pt.L ZCH AECB Silv. PassivHaus

FEE: TargetkWh/m2.a

42.3 41* 40 15

Floors 0.15 0.11 0.11 0.10

Walls 0.18 0.14 0.14 0.11

Roof 0.18 0.11 0.09 0.10

Windows 1.4 1.4 0.85 0.85

Bridging 0.085 0.04 0.01 0.01

Permeability 4 m3/m2/hr 2 m3/m2/hr 1.5 ac/hr ** 0.6 ac/hr

Ventilation Extract only MVHR MVHR MVHR

* Zero Carbon Home FEE targets vary with house type (end-terr/mid-terr/flats etc)

** AECB Silver permeability is 3.0 ac/hr for homes with MEV only – but harder to achieve other targets in the standard

S t a n d a r d s c o m p a r e d ( i n d i c a t i v e v a l u e s f o r r e c e n t p r o j e c t s )


• Insulation is cheap – it doesn’t

breakdown or need periodic

servicing

• Minimising thermal bridging needs

careful detailing and clear

explanation

• Installation can be poor and

needs careful quality control

• Site teams need to understand

the importance of installing

insulation without gaps or air

pathways

G o i n g f o r h i g h e r s t a n d a r d s – c a n w e d o i t ?


• Airtightness needs to be

considered from the outset,

designers need to understand the

sequence of building operations

• Complexity is the enemy of

airtightness – try and find the

simple solutions your site team

will be much calmer!

• Test early and test often – don’t

kid yourself that you can fix it

later!

• Don’t run with scissors (or drills, or

knock holes through things with a

big hammer!)



• Service installations should be

planned and accommodated at

design stage

• Ventilation systems should be

installed and commissioned by

suitably experienced installers

• Your plumber / electrician will

always know how to do it better /

quicker / cheaper. Try to persuade

them to do it right!

• User controls should be simple

and located where they are

needed (don’t tuck them away

behind the plant!)



• You will spend a lot of time in the planning stage agreeing how to deliver higher standards

• You will spend a lot of time with the pre-contract team agreeing how best to deliver higher standards

• You will need to spend time with the site team explaining why things are being done this way

• You will tear your hair out when you learn that the site surveyor is pleased that s/he saved £5 on a cheaper tape (that doesn’t actually stick!)



• YES WE CAN!

• Our PassivHaus project in South Oxfordshire – built by a small local contractor that had never built PassivHaus or ICF before

• Completed on-time & in-budget

• First air tightness test – 0.48 ac/hr

• PassivHaus certified even though it faces north west

• Perhaps doing things differently we think more about what we are doing and don’t make assumptions based on previous experience


gcp : architecture : energy : sustainable design

Thank you

www.gcparch.co.uk

[email protected]

“The House works really well –

now we have experienced living

in a PassivHaus, we wouldn’t

want to live in anything else.”

(Client – Warborough PassivHaus)

colin powell gcp architecture slides

Environment