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Environmental Assessment

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• How do we design a sustainable building?• How can we tell if our building is sustainable?• How does our design compare with others?• Can we trust the claims of others?

BREEAM

Building Research Establishment Environmental Assessment Method

BREEAM

• BREEAM is an international standard for the environmental assessment of buildings – it is voluntary, in excess of building regulations and other legislation

• Originally launched 1990

BREEAM• A set of sustainable design objectives in 9-10

key areas, with specific targets• Available on-line (link shown later >>)

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BREEAM aimsto:• Mitigate impacts of buildings on environment• Enable buildings to be recognised according

to their environmental benefits• Provide a credible environmental label for

buildings• Stimulate demand for sustainable buildings

BREEAM objectives 1

• Provide market recognition to low environmental impact buildings

• Ensure best environmental practice is incorporated in buildings

• Set criteria and standards surpassing those required by regulations and challenge the market to provide innovative solutions that minimise the environmental impact of buildings

BREEAM objectives 2

• Raise the awareness of owner, occupants, designers and operators of the benefits of buildings with a reduced impact on the environment

• Allow organisations to demonstrate progress towards corporate environmental objectives.

Criteria for issues to be considered in BREEAM• Issues for assessment are agreed to be significant,

and offer worthwhile reductions in environmental impact

• Issues must be assessable at the relevant stage in the building’s life

• Performance levels are based on scientific evidence wherever possible

• Performance levels must exceed the demands of law and regulations and encourage innovation

• Improvements encouraged by BREEAM are achievable

Credibility of BREEAM

• 115 000 buildings certified in UK• Over 700 000 homes and buildings

currently registered in UK for assessment

• Can be used anywhere in the world

Brief

• Assessment criteria 5: • Technical, energy and environmental strategies and

solutions will show an understanding of human comfort needs and local and global environmental impacts.

• Submission requirement for Phase II:• Environmental strategies, energy analysis data

environmental rating process, including your reflections on the implications of these for design

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Other systems:LEED

• US system, launched in 1998• Originally inspired by and based on BREEAM• Leadership in Energy and Environmental Design • LEED is run by the US Green Building Certification

Institute (set up by USGBC)• USGBC has about 6500 paying members• Highest LEED rating is ‘Platinum’; others are Gold,

Silver and Certified • There is now a UK Green Building Council too

LEED

The USGBC, says that LEED was created to:• define "green building" by establishing a common

standard of measurement• promote integrated, whole-building design practices• recognize environmental leadership in the building

industry• stimulate green competition• raise consumer awareness of green building benefits• transform the building market.

How do BREEAM and LEED compare?

BREEAM• 115 000 buildings assessed in UK• Independent body (BRE)

regulates scheme• Professionals can train and

register as an assessor• ?Same building scores lower on

BREEAM – ie more difficult to get high score

• Greater focus on environmental impacts

• BREEAM International is tailored to suit local climate and regulations

LEED• 1500 buildings assessed• Membership based GBC regulates

scheme• Assessment is carried out within

USGBCI• ?Same building scores higher on

LEED – ie it is easier to get high score

• More importance given to occupant health

• LEED is based on US regulations and may not respond to local environmental issues

Other Environmental Assessment systems

• Australian Greenstar system - awards stars: Six Stars ****** is highest rating

• However, like LEED, compared to BREEAM Excellent, it does not represent such a good environmental performance

• CASBEE – Japanese system – run by the Japan GreenBuild Council and Japan Sustainable Building Consortium

Passivhaus standards for central Europe

- energy and comfort only• German and Swedish origin – Passivhaus Institute based in

Darmstadt, Germany• Started with houses, but now applicable to different building

types as well• Energy based assessment, using spreadsheet, with key targets:

- insulation U-value of 0.15W/m2K- max. air leakage at 50Pa ≤0.6V/hr- max. energy use of 15 kWh/m2/yr- max. primary energy ≤ 120kWh/m2/yr

• Passivhaus buildings often have no heating systems!

Many building types can be assessed

BREEAM schemes are available - scoped to suit the specific building types and, in the case of International BREEAM, the local regulations, climate etc

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BREEAM schemes

• BREEAM Other buildings• BREEAM Courts• BREEAM Education• BREEAM Communities• BREEAM Industrial• BREEAM International• BREEAM Healthcare• BREEAM Offices

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• BREEAM Retail• BREEAM Prisons• BREEAM Multi-residential• BREEAM Data centres• Code for sustainable homes (replaced Ecohomes in

2007 for new housing)• BREEAM Ecohomes (still in use for refurbished

housing in England and new housing in Scotland)• Ecohomes XB (for stock profiling)• BREEAM Domestic refurbishment (under

development)

BREEAM in detail

Building Research Establishment Environmental Assessment Method

Various types of project can be assessed

• New construction• Major refurbishment to existing buildings• A combination of new construction and

refurbishment• New construction or major refurbishment

which forms part of a larger mixed use building

• Existing building fit-out

Levels of achievement and points required

Outstanding ≥85Excellent ≥70Very good ≥55Good ≥45Pass ≥30

BREEAM

What categories would you include in an environmental assessment rating?

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Categories in BREEAM CSH

• Management• Health and well-being• Energy and CO2• Water• Materials• Waste• Ecology• Pollution• Surface water runoff

Credit weightings• The code gives different weightings to different

categories.• Would you rate some categories more highly than

others?

• Management• Health and well-being• Energy and CO2 emisions• Water• Waste• Ecology• Pollution• Materials• Surface water run off

Credits (by %) in BREEAM CSH

Category %• Management 10• Health and well-being 14• Energy and CO2 36• Water 9• Materials 7• Waste 6• Ecology 12• Pollution 3• Surface water runoff 2

Structure of each BREEAM issue

• Issue information• Aim• Assessment criteria

(including Exemplary Level Criteria, where applicable)

• Compliance notes –relating applicability to project type

• Schedule of evidence required

• Additional information

The Code for Sustainable Homes

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Code for Sustainable Homes

• A single national standard for sustainable homes – it was originally voluntary, but was made compulsory for social housing from May 2008

• All new homes (and most other homes when they are sold) now need an Energy Performance Certificate

The Code for Sustainable Homes (CSH)

• Government standard, launched December 2006• A set of sustainable design principles in 9 key areas• Builds on BREEAM EcoHomes standard – effectively

replacing it

Technical guide

current version:Nov 2010300 pages!

provides detailed information on how to do the assessment

https://www.gov.uk/government/publications/code-for-sustainable-homes-technical-guidance

Stages in assessment process under the Code for Sustainable Homes

1 Design Stage

2 Post-construction stage

• Set of performance targets (in excess of the Building Regulations)

• Assessed at the level of the individual dwelling

• Certain minimum mandatory standards (for CO2, water, materials, Lifetime Homes, waste and surface water run-off) which must be achieved before even the lowest level of the Code can be met (indicated by (M) in the tables)

Rating system

• From one to six stars• Level One () - minimum standard• Level Six () = a ‘Zero-

Carbon home’

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Government targets2010 – Level 3 – (25% improvement* in CO2 ) now

in building regulations

2013 – Level 4 – 44% improvement over 2006 Regs or 25% DER over TER

2016 – Level 6 – ‘Zero Carbon’

* Reduction compared with part L of Building Regulations

Zero carbonNet carbon emissions resulting from allenergy used in the dwelling is zero.

Site wide and dwelling issues

• Site wide issues – features shared with all other dwellings on the site

• Shared issues – access to some common facility• Dwelling issues – related to the performance of the dwelling

itself

Weighted value of each creditEnergy (Ene)

credits• Dwelling emission rate (DER) (M) 10 >• Fabric energy efficiency (M) 9• Energy display devices 2• Drying space 1• Ecolabelled white goods 2• External lighting 2• Low/Zero carbon 2• Cycle storage 2 >• Home office 1 >

TOTAL 31

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Ene 1: Dwelling emission rate

• Credits range from 1 (for 10% improvement of DER over TER (Target Emissions Rate) to 14 (for 100% improvement) and 15 (for zero carbon)

• You can use the NHER program to create SAP ratings, to check performance against the energy ratings.

• Electrical energy for lights and appliances must be included.• The use of a proportion of renewable energy will help to reduce

the CO2 emissions

Ene 8 – Cycle storage requirements:

1 bed 1 cycle space2 and 3 bed 2 spaces4 bed 4 spaces

• Must be safe and weatherproof• Space req’d: 2m x 0.75m per bicycle

Storage space for cycles

Ene 9 – Home office

Provision of space and services for a home office:• Min 1.8m wall (to allow space for desk and shelving) • Window• Adequate ventilation• 2 No double sockets, • 2 tel sockets or broadband

Old EcoHomes standard: TransportTra3 – Local amenities

80% of development must be within walking distance of facilities:

• Within 500m of food shop and post box• Within 1000m of 5 of the following: postal facility,

bank/ cash machine, pharmacy, primary school, medical centre, leisure centre, community centre, public house, children’s play area, public park or village green

• Safe pedestrian routes to the local amenities

Water (Wat)• Indoor water use (M) 5• External water use 1

TOTAL 6

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Materials (Mat)• Environmental impact (M) 15• Responsible sourcing – basic elements 6• Responsible sourcing – finishing 3

TOTAL 24

table from The Green Guide to Specification – based on elemental analysis – ie comparing

whole roof or wall constructions – not individual materials

Surface water• Surface water run-off (M) 2• Flood risk 2

TOTAL 4

Waste• Storage (M) 4• Construction waste management 3• Composting 1

TOTAL 8

Pollution• GWP of insulants 1• NOx emissions 3

TOTAL 4

Health and well being• Daylighting 3 >• Sound insulation 4• Private space (1.5m2/b’rm) 1 >• Lifetime homes (M) 4

TOTAL 12

Hea1: Daylighting

According to BS8206:pt2, adequate daylight is:• 2% DF in the kitchen• 1.5% in Living rooms, Dining rooms and Studies• The view of the sky in Living rooms, Dining rooms

and Studies must be over 80% of the room at a height of 0.85m

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View of sky

At the no-sky line, that last visible patch of sky above the obstructions will just disappear when the window head is slighted through a point at working plane height

Old EcoHomes standard for Sunlight

Littlefair, PJ (1991) Site layout planning for daylight and sunlight. (BRE report BR209) BRE.

• In general, a dwelling or non-domestic building which has a particular requirement for sunlight, will appear reasonably sunlit provided that at least one main window faces within 90deg of Southand

• On this window wall, All points on a line 2m above GL are within 4m of a point from which no obstruction in the section at 90° to the wall, subtends an angle of more than 25°to the horizontal.

25°

2m

Hea3: Private space

Must be of a size that allows all occupants to sit outside

• 1.5 m2 per bedroom• Allow easy access to all occupants• Accessible only to occupants of designated dwellings

Old EcoHomes standardHea3 Private space

• Must be of a size that allows all occupants to sit outside:- 1.5m2 per bedspace- Minimum 3.0m2 per home- Allow easy access to all occupants- Be accessible only to occupants of the designated dwellings

Management

• Home user guide 3• Considerate constructors 2• Construction site impacts 2• Security 2

TOTAL 9

Ecology (Eco)

• Ecological value of site 1• Ecological enhancement 1• Protection of ecological features 1• Change in value 4• Building footprint (net to ground ratio) 2 >

TOTAL 9

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Eco 5: Building footprint

Floor Area (GFA): Footprint ratio > 3:1 for houses and 4:1 for flatsie:Gross internal floor area : Site area of development (parts with permanent foundations)

Gross Floor Area (GFA) is the area contained within the inner face of external wallsFootprint Area is the area enclosed within the external faces of all buildings on permanent foundations – ie including garages and outbuildings. (NB building on stilts will not reduce Footprint Area!)

Points required to achieve each code level

How does the code compare with other ratings?

• Passivhaus = code level 5

• CarbonLite standards (AECB scheme)- Silver = code level 4- Passivhaus = code level 5- Gold = code level 6

CarbonLite

CarbonLite• U-values = 0.15 W/m2K• Window:Floor ratio of 18-30%• MVHR• Refrigerative cooling systems (incl. reversible

heat pumps) not permitted• Heating system Gas, LPG, or Oil or earth-

source heat pump (wood chip discouraged in gas supply area)

• Glass area ≥ 16% of floor area

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BRE Innovations Park

BRE Innovations Park BRE Innovations Park

Stewart MilneSigma HomeNear zero-carbon

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‘Lighthouse’ – code level 6: ‘Zero Carbon

Lighthouse at BRE Innovations Park

MVHR

Mechanical Ventilation Heat Recovery unit

Stale air is extracted from wet rooms (bathrooms and kitchens) and fresh air enters living rooms and bedrooms

MVHR unit at BRE Innovations Park

Modular

Check and consider:• Spacing for daylighting and solar

access• Energy sources and systems• Water – sources, storage, • Construction methods and materials• Ways of living that reduce carbon

emissions

Spacing for daylighting

Consider the worst case – the ground floor units – and design for them ideally

Spacing for solar access

Student housing in Orestad, Copenhagen

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Note that the solar panels on this house are entirely shaded!

12:30 on 1 November

CSH – any misgivings about the system?

• Any misgivings?• Energy use based on modelling rather than actual

energy consumption!• Some credits seem quite easy to achieve – eg,

daylight requirements are not that onerous

How might the Code for Sustainable Homes be improved in future?

• ?• Change the weightings?• On-site food production?

productive gardenunproductive garden

highly productive garden!

heat and energy from waste – which can later be used as compost

Michael Pawlyn

… if we are to reduce carbon emissions by 80%, then we need to radically re-think everything we do…

R&Sie(n)[AR Oct 09]

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Masterplan intercrit - Friday

• Half hour per team total including comments• Models, paper drawings and digital • In Crit Space• Start loading your work at 09:00• All work to be in place by 09:30 at the latest• Crits start at 10:00 sharp!

• Remember you must identify your building and have sketch ideas for how it will work, in plan and section, internally/externally within the masterplan