Blake Lapthorn's green breakfast with guest speaker Keeran Jugdoyal, Faithful+Gould

End Use of

Sustainable Buildings

Lessons Learnt

13th November 2013

1. An introduction to sustainable buildings

2. The challenges to achieving them in reality

3. Post occupancy evaluation of sustainable buildings

4. Case study of the Marks & Spencer Sustainable Learning Store

5. Questions and answers

Agenda

Impacts of the built environment

• The construction and maintenance of buildings is responsible

for around half of UK carbon dioxide emissions.

• The construction industry consumes around 6 tonnes of

materials per year for every person living in the UK

• More than 400 million tonnes of materials get delivered to site

each year. Of these 60 million tonnes go straight to tip.

Regulatory and other drivers

• Revisions of Part L of the Building Regulations

• EU Energy Performance of Buildings Directive

• DEC’s and EPC’s

• Code for Sustainable Home

• Tax incentives

• Zero Carbon Targets

• 2016 for homes

• 2019 for non-domestic buildings

Recent Sustainable Buildings

Co-op Headquarters World Wildlife Fund Headquarters

The Performance Gap

Most sustainable buildings do not perform as

well as the initial design claim

After a year of operation, London City Hall was consuming a reported 50% more energy than it had been predicted to consume

Pre-Occupancy Measures

• BIM and Soft Landings

• BREEAM

Pro

ject

tea

m e

ffo

rt

Briefing

Stage B

Design

Development

Stage D

Pre-

Handover

Stage P

Initial

Aftercare

Stage A

Years 1 to 3

Extended Aftercare

Stage Y

• Technique for understanding how buildings are performing

• Includes monitoring of performance and occupant satisfaction

• Energy, carbon, waste, water, satisfaction, productivity

What is Post Occupancy Evaluation?

• Understand the gap between design and actual performance

• Understand the importance of occupant engagement

• Save money

• Put greater onus on the design team / contractor

• Test if renewables worked

Why use it?

Productivity gains

Marks & Spencer Cheshire Oaks Eco Learning Store

Located in the Cheshire Oaks Retail Park near

Ellesmere Port

Gross internal area: 19,500 m² Net sales area: 13,800 m²

Covering two floors Complete with three cafes and a

extensive food hall

Plan A aspirations: Reduce the impact of M&S buildings

on the environment and become come more resource efficient

Building features

• The roof is made of FSC-certified glulam timber.

• 230 prefabricated Hemclad® panels have been

used in the wall delivering a design U value of

0.12.

• Aluminium “white” roof reflects excess heat.

• North lights in the roof to maximise the use of

natural light

• High level of air tightness <3m³/hr.m² @ 50 Pa

Low Carbon Building Services

• 300 kW wood pellet boiler

• Displacement ventilation system with six

independently controllable zones and free cooling

• Automatic light dimming system to utilise daylight

where available

• CO2 refrigeration system with CO2

piped directly to food cabinets and

cold rooms.

• Heat reclaim on the refrigerators.

• 80,000 litre rainwater harvesting

system predicted to reduce mains

water consumption by 25%

Biodiversity

• 300 m² living wall with 30 plant species.

• The retention of a swale area and pond

• 228 new trees

• 9 swift boxes have been built into the wall at concealed location for mating swifts to use.

• A further 6 bird boxes in the perimeter fence

• Wildflower meadow bank around edge of the store

Staff and customer enhancements

• Transport enhancements

o Improvements to cycle ways, crossings, roadway and

footpaths

o Contribution towards improved bus services

o Electric car charging points

o Staff shower and cycle stands to encourage cycling

• 400 new jobs

• Educational visits to schools and universities

• Interactive information points throughout the store

Planned activities

Overview of POE Tasks • 1 year’s worth performance monitoring

• Assess building envelope

• Benchmark against other buildings in the M&S portfolio

• Assess the sustainable features

• Survey staff and customers

• Review biodiversity

• Disseminate the good practice lessons

Questions the POE aims to answer

• Which features work, and which do not?

• Is the extra effort involved in providing these features worth the effort?

• Are operational costs reduced? – Initial signs are promising as we will see.

• Do the store’s features attract more customers and generate more sales?

• What are the key lessons to be carried over to future developments?

Performance Targets for the Store

Design and construction data

• To fully understand the post occupancy performance of a building, an understanding is required of the events leading up to it being put into use.

• Design documents provide the basis of understanding how the building was originally intended to operate.

• Issues arising during construction can cause the design of a building to be altered away from the original intent.

• Issues arising during the operational phase

can sometimes trace their roots back to

issues at the design, construction or

commissioning phase.

Measuring Energy Performance

Building management system

Monthly energy reporting

Sample monthly energy report

Lighting – Electricity use carpet plot

Days over the monitoring period

Ho

urs

of

the

day

Good at switching off outside trading hours.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

1:00

2:00

3:00

4:00

5:00

6:00

7:00

8:00

9:00

10:00

11:00

12:00

13:00

14:00

15:00

16:00

17:00

18:00

19:00

20:00

21:00

22:00

23:00

0:00

Building Fabric Performance

Contractor’s survey focused on integrity of the insulation

F+G’s survey focused on the building’s heat

loss

Building fabric performance

External temperatures less then 0°C

Thermal imaging surveys cannot verify air tightness of a building and therefore other methods are required.

21.30°C

20.65°C

23:00 07:00

Biodiversity findings

• Sources of information include:

Pre-construction habitat survey

Post-construction habitat survey

BREEAM retail assessment

Site biodiversity meeting

• A site biodiversity action plan has be

produced. The plan has 9 site specific

targets which are all on track to be

achieved - examples:

No loss of amphibian breeding,

foraging and shelter habitat.

Retain and protect hedgerows

where practicable

Results

Electricity performance against benchmarks

Staff Survey

Lessons learnt from Cheshire Oak

Key factors that contribute to the successful operation of the building:

• Clear vision for the building expressed through Plan A and the

Sustainable Construction Manual.

• Close collaboration with designers and contractors throughout the

construction and commissioning process.

• Detailed hand-over process with clear operation and maintenance

manuals.

• Post occupancy workshops which bring together designers, contractors

and facilities staff to examine the building’s performance in use.

Lessons learnt continued

The fundamental principles of energy efficient building design

are well known. Don’t lose sight of them:

• Good insulation

• High levels of air tightness

• Limited thermal bridging

• Maximise natural light

• Reduce solar gains

• Simple HVAC systems are easier to control and

monitor

Lessons Learnt Continued

Issues encountered:

• Difficult to assess the performance of certain sustainable features due to

lack of consideration to monitoring at the design stage.

• Initial resistance from some stakeholders not use to sharing information with

third parties.

• Challenging to interpret some of the data received without knowing the day

to day activities in the building.

Conclusions

• Post Occupancy Evaluations can provide feedback on how a buildings are

performing against original concept.

• The assessment of the hard technical measures such as energy use must be

performed in tandem with soft analysis from the building users in order to

provide meaningful results.

• The process allows operational savings to be identified that might never be

spotted in the normal day to day operations of a building. Hence the

importance of using third parties.

• It provides good quantitative data on how a building is performing that can be

used to inform future building projects.

• The techniques can be applied to assess existing poor performing buildings.

Keeran Jugdoyal

Senior Engineer

keeran.jugdoyal@fgould.com