PassivOffice at Devonshire Gate

PassivOffice @Devonshire Gate

architects • engineers integrated sustainable design mechanical engineering natural ventilation design passivhaus consultancy healthy building design landscape design permaculture design building monitoring research & development

Exeter Office Exeter Bank Chambers 67 High Street Exeter Devon EX4 3DT Tel. 01392 279220 Fax. 01392 279036

Bideford Office 18 Market Place Bideford Devon EX39 2DR (Registered Office) Tel. 01237 474952 Fax. 01237 425669

www.ecodesgn.co.uk

Project Team

Our Team

• David Disney, Devonshire Gate Client • Gale & Snowden Project Managers Architects, Mechanical Engineers, Landscape

Passive natural vent

Permaculture design

• Exeter University • Jenkins Hansford Partnership - QS

Passivhaus certified

Landscape integration

The Project

Site plan

- RIBA Workstage EFG

The Project

- RIBA Workstage EFG

New Office Project • • • •

First Phase 1250 sqm Passivhaus design Natural ventilation in summer • Optimum day light • Planning restrictions • RIBA Workstage E/F/G Low energy - Healthy - Integrated landscape

Adaptation Issues Key Issues • Increased internal temperatures • Increased external temperatures • Changing rainfall patterns • Localised air pollution • High internal gains • Daylight Requirements • Increased weather severity

Methodology Solar XXI Building (Lisbon, Portugal)

Analysis

• Literature research • Case studies • Thermal modelling past projects with future weather files • Ongoing IES thermal modelling • PHPP (Passive House Planning Package) • Occupant heat stress & impact on productivity analysis • Cost matrix • Integrated team studio working Day light modelling In IES

Methodology Climate Risk Radar

Climate change related risks are rated for their probability and their potential impact resulting in a risk magnitude.

Following detailed analysis of building’s exposure to climate change related risks, the 2030, 2050 & 2080 @ 50 percentile with high CO2 emission scenario was chosen.

Findings - Thermal Comfort

The same design principles that reduce heat energy losses in winter will help to reduce overheating in summer.

Findings - Thermal Comfort Super insulated envelope

The same design principles that reduce heat energy losses in winter will help to reduce overheating in summer.

Findings - Thermal Comfort Super insulated envelope

High performance windows

The same design principles that reduce heat energy losses in winter will help to reduce overheating in summer.

Findings - Thermal Comfort Air tight construction

Super insulated envelope

High performance windows

The same design principles that reduce heat energy losses in winter will help to reduce overheating in summer.

Findings - Thermal Comfort Air tight construction

Super Thermal insulated Bridge envelope free

High performance windows

The same design principles that reduce heat energy losses in winter will help to reduce overheating in summer.

Findings - Thermal Comfort Air tight construction

Super Thermal insulated Bridge envelope free

High performance windows

Important: In a Passivhaus night cooling is very effective and a successful natural ventilation strategy will reduce the risk of overheating considerably

Findings - Thermal Comfort Air tight construction

Super Thermal insulated Bridge envelope free

High performance windows

Additional measures to reduce the risk of overheating Thermal mass in combination with night cooling Inclusion of thermal mass

Findings - Thermal Comfort Air tight construction

Super Thermal insulated Bridge envelope free

High performance windows

Additional measures to reduce the risk of overheating External shading via roof overhangs or flexible blinds External shading

Inclusion of thermal mass

Findings - Thermal Comfort Air tight construction

Super Thermal insulated Bridge envelope free

High performance windows

Additional measures to reduce the risk of overheating Intelligent window control system to optimise ventilation rates External shading

Inclusion of thermal mass

Intelligent Window control

Findings - Thermal Comfort Air tight construction

Super Thermal insulated Bridge envelope free

High performance windows

Additional measures to reduce the risk of overheating

External shading

Inclusion Reduce of thermal Internal mass gains

Intelligent Window control

Reduction of internal heat gains by moving heat sources outside the thermal envelope (eg servers etc)

Air tight construction

Super Thermal insulated Bridge envelope free

High performance windows

Thermal modelling results – Frequency of overheating

Findings - Thermal Comfort

Additional measures to reduce the risk of overheating

External shading

MVHR Ground cooling

Inclusion Reduce of thermal Internal mass gains

Intelligent Window control

Supply air reduced by 10°C in summer combined with closing windows above 22-25°C reduces overheating to zero in 2080 Now 2030 2050 2080

Findings – Landscape

1. Planting micro climates

Findings – Landscape Green roof Attenuation Evaporation cooling

1. Planting micro climates

Findings – Landscape Green roof Attenuation Evaporation cooling

Transpiration cooling

1. Planting micro climates

Findings – Landscape Reduce hard surfaces next to building

Green roof Attenuation Evaporation cooling

Transpiration cooling

1. Planting micro climates

Findings – Landscape Shading from trees

Reduce hard surfaces next to building

Green roof Attenuation Evaporation cooling

Transpiration cooling

1. Planting micro climates

Findings – Landscape Shaded external working areas

Shading from trees

Reduce hard surfaces next to building

Green roof Attenuation Evaporation cooling

Transpiration cooling

1. Planting micro climates

Alternative Landscape Design

Findings – Landscape Shaded external working areas

Shading from trees

Reduce hard surfaces next to building

Green roof Attenuation Evaporation cooling

Transpiration cooling

1. Planting micro climates 2. Resilient landscaping

Ponds to moderate flood/drought cycle

Findings – Landscape Shaded external working areas

Shading from trees

Reduce hard surfaces next to building

Green roof Attenuation Evaporation cooling

Transpiration cooling

1. Planting micro climates 2. Resilient landscaping

Ponds to moderate flood/drought cycle

Earth bank and trees act as windbreak

Findings – Landscape Shaded external working areas

Shading from trees

Reduce hard surfaces next to building

Green roof Attenuation Evaporation cooling

Transpiration cooling

1. Planting micro climates 2. Resilient landscaping

Ponds to moderate flood/drought cycle

Earth bank Planted areas and trees act to increase as windbreak infiltration

Findings – Landscape Shaded external working areas

Shading from trees

Reduce hard surfaces next to building

Green roof Attenuation Evaporation cooling

Transpiration cooling

1. Planting micro climates 2. Resilient landscaping

Ponds to moderate flood/drought cycle

Root system for erosion control and slope stabilisation

Earth bank Planted areas and trees act to increase as windbreak infiltration

Design for severe weather Driving rain •robust timber rain screen cladding •enhanced window and door specification and detailing

Increased wind severity

•eaves and verge robust details •Robust materials and secure fixings

Increased UV •turf roof •timber cladding

Future adaptability •future addition for shading devices •Future external working areas

Flooding events

•oversized rainwater goods and drains •attenuation ponds

Passivoffice @ Devonshire Gate detail design drawings

Lifecycle Costing Cumulative Discounted Energy Related Costs for an Office Building Built to 2010 Building Regulation Requirement

Energy Costs Standard Office

£4,500,000.00 £4,000,000.00 £3,500,000.00 £3,000,000.00 £2,500,000.00 £2,000,000.00 £1,500,000.00 £1,000,000.00 £500,000.00 2090

2088

2086

2084

2082

2080

2078

2076

2074

2072

2070

2068

Lighting Costs

2066

2064

2062

2060

2058

2056

Cooling Costs

2054

2052

2050

2048

2046

2044

Heating Costs

2042

2040

2038

2036

2034

2032

2030

2028

2026

2024

2022

2020

2018

2016

2014

2012

2010

£0.00

Energy costs represent net present values and include inflation and a 30% reduced heating energy demand from 2050 onwards.

Lifecycle Costing Cumulative Discounted Energy Related Costs for a Passive Office Designed by Gale & Snowden Architects

Energy Costs PassivOffice

£4,500,000.00 £4,000,000.00 £3,500,000.00 £3,000,000.00 £2,500,000.00 £2,000,000.00 £1,500,000.00 £1,000,000.00 £500,000.00

2090

2088

2086

2084

2082

2080

2078

2076

2074

2072

Lighting Costs

2070

2068

2066

2064

2062

Cooli ng Costs

2060

2058

2056

2054

2052

Heati ng Costs

2050

2048

2046

2044

2042

Additi onal Investment

2040

2038

2036

2034

2032

2030

2028

2026

2024

2022

2020

2018

2016

2014

2012

2010

£0.00

Energy costs represent net present values and include inflation and a 30% reduced heating energy demand from 2050 onwards.

Lifecycle Costing Gale & Snowden Design vs Standard OfficeEnergy Building - Comparison Cumulative Discounted Related Costs of Cumulative Discounted Cash Flows for a Passive Office Designed by Gale & Snowden Architects

Comparison PassivOffice vs Standard Office

£4,500,000.00 £4,500,000.00 £4,000,000.00 £4,000,000.00 £3,500,000.00 £3,500,000.00 £3,000,000.00 £3,000,000.00 £2,500,000.00 £2,500,000.00

Payback of additional initial investment after 12 years.

£2,000,000.00 £2,000,000.00 £1,500,000.00 £1,500,000.00 £1,000,000.00 £1,000,000.00 £500,000.00 £500,000.00

2090

2088 2090

2086 2088

2086 2084

2084 2082

2082 2080

2080 2078

Lighting Costs

2078 2076

Adapted Cooli ngBuilding Costs

2076 2074

Standard Building Additi onal Investment Heati ng Costs

2074 2072

2072 2070 2070 2068 2068 2066 2066 2064 2064 2062 2062 2060 2060 2058 2058 2056 2056 2054 2054 2052 2052 2050 2050 2048 2048 2046 2046

2044 2044 2042 2042

2040 2040

2038 2038

2036 2036

2034 2034

2032 2032

2030 2030

2028 2028

2026 2026

2024 2024

2022 2022

2020 2020

2018 2018 2016 2016 2014 2014 2012 2012 2010 2010

£0.00 £0.00

Opportunities

Challenges

Simple, low cost measures incorporated at the

Lack of guidance

beginning of the design process can create robust, low energy buildings, future proof against climate change

Weather file Selection

Adoption of Passivhaus standards combines low energy buildings with excellent summer comfort

An integrated project team applying good practice building physics is key to enable architecture to perform in present and future climates

Swim4Exeter (D4FC 2) 60% Energy reduction and excellent summer comfort without air conditioning Exeter Extra Care (D4FC 1) Vulnerable user group Air conditioning could be avoided into 2080 with a passive approach

Compatibility with current good practice guidance Late consideration of climate change risks

PassivOffices (D4FC 2) Low energy use and excellent summer comfort without air conditioning

Thank You Swim4Exeter (D4FC 2) 60% Energy reduction and excellent summer comfort without air conditioning Exeter Extra Care (D4FC 1) Vulnerable user group Air conditioning could be avoided into 2080 with a passive approach