1. Innovative Refurbishment Garth House 10 th June 2014 Bicester Town Council

2. Alex Towler – BioRegional Project Manager Adrian Kite - Ridge Architect Rajat Gupta Oxford Brookes University

3. Innovative Refurbishment 1.TSB Competition 2.Aims and Objective 3.Design Team 4.Project Programme 5.Innovation 6.Internal Insulation 7.Secondary Glazing 8.Winter Ventilation 9.Summer Ventilation 10.Result

4. Innovative Refurbishment Technology Strategy Board competition challenge to improve the energy efficiency of existing non-domestic buildings through innovative refurbishments. Funded by the Department for Energy and Climate Change (DECC) R+D Project with potential for large scale roll out.

5. Aims and Objectives Develop a holistic insulation solution for historic and non-residential buildings combining: internal insulation, secondary glazing and ventilation strategy for both winter and summer modes. 30% cheaper than traditional methods 37% carbon reduction 58% energy reduction Improvement in comfort both winter and summer Minimal disruption to occupants Use of multi skilled workforce Monitor and evaluate before and after work

6. Ridge – Lead Designer Adrian Kite Architect – Post Graduate In Energy Efficient Building Passive House – low energy designer / TSB Retrofit for the Future RIBA Conservation Register / Abingdon Council Hall Museum Grade 1 Listed BioRegional – Project Co-ordinator Alex Towler Sustainability Consultant. BioRegional - An environmental charity with a focus on built environment and One Planet Living Oxford Brookes University – Monitoring and Evaluation Professor Rajat Gupta Professor of Sustainable Architecture and Climate Change. Director of the Oxford Institute for Sustainable Development (OISD) Director of OISD: Low Carbon Building Group Dr Hu Du Lecturer in Architecture and Building Simulation OISD: Low Carbon Building Group Design Team

7. Kingerlee – Main Contractor Local Oxford Contractor TSB / Energy Reduction Experience Own Natural Building Technologies United House - WHISCERS license Internal insulation contractor BISRIA – Project Assessor Ian Orme Technology Strategy Board Julie Meikle Design Team

8. Monitored and Evaluated by Oxford Brookes University Winter Issues Heating system on continuously in winter - 24hrs / day Heavy weight structure provides slow response time Heating system is not zoned. TRV’s not utilised. Wasted heat loss through walls, single glazing and ground floor. Summer Issues Council Chambers overheating Conservatory heats up in summer with no opening lights Sufficient windows not being opened Existing Building

9. Competition for funding in two funding phases: Nov 2012: Phase 1 Application– Innovation Concepts Selected Phase 1 funding awarded - £20k Feb – April 2013: Phase 1 Design phase – Desk top study Phase 2 funding awarded - £839k August – Sept 2013: Detail Design Dec 2013 – March 2014: Construction Period March 2014 – March 2015: Monitoring Phase. Project Time Line

10. Innovation A 3D laser scanner measures the internal dimensions of a room. The digital data is then downloaded to an off-site cutting machine. The machine cuts the insulation boards with great accuracy. Software optimises the cut to minimise wastage. The boards are delivered to site as a kit and are then fitted to the walls with the minimum of noise, mess and disruption.

11. Internal Insulation 70mm Kingspan K18 Kooltherm Insulated plasterboard 25mm treated softwood batten on existing plastered walls Skirting replaced Retain existing window mouldings by stopping insulation before existing window Reduced heat loss through walls Reduced heat loss through draughts

12. Internal Insulation

14. Existing Panelling

15. Secondary Glazing

17. Winter Ventilation Mechanical Ventilation with Heat Recovery (MVHR) Provides fresh air in winter when: windows are not opened sufficiently buildings are better sealed removing natural air changes Provides tempered fresh air without effecting internal temperatures through draughts

18. MVHR Installation

19. Second Floor Works

21. Aerogel Insulation Spacetherm C from the Proctor Group 10 mm areogel 18mm chip board K-value 0.014 U-value ca 0.4

22. Summer Overheating Summer overheating potential increases due to internal insulation Opening existing windows is key Cross ventilation is required Conservatory needs opening vents Council Chambers heat gain on both sides requires heat dump vents

23. Summer Ventilation

25. Passivent Internal cover grille Controllable motorised louvre External weather louvre Aircool wall ventilator in masonry wall

26. Proposed Elevations

28. Result Warmer in Winter with faster more responsive heating More efficient use of the existing heating system Comfortable in Summer with automated natural vent in the Council Chambers Bright Good air quality Happy Occupants User focused 1+ Years Monitoring Data Existing building character retained

29. Handover and Training

30. Building performance evaluation and Energy modelling Pre-refurbishment BPE Energy assessment Environmental audit Occupant feedback Modelling post-refurbishment building performance Energy savings Avoiding overheating risk in summer Post-refurbishment BPE

31. Objective of BPE Evaluate the performance of the refurbished building in terms of energy savings, overheating in summer and the effect of combined ventilation strategies. Measure the moisture content of insulation materials in winter. Identify the role of occupants in minimising energy use, from full time staff to visitors. Increase the understanding of the relationship between intended performance and actual performance in-use.

32. Pre-refurbishment BPE

33. BPE methodology

34. Energy consumption before refurbishment kWh/m 2 Actual gas consumption was calculated based on meter readings between 18/02/2011 and 02/04/2013; Actual electricity consumption was calculated based on readings between 21/07/2011 and 18/07/2013.

35. Monitoring of environmental conditions Total 315 occupied hours in 7 weeks starting from 18 Feb 2013 Office F10Office F13Office F19Office F21Office G25 Percentage of occupied hours above 24 o C 16%12%0%7%5% Percentage within comfort range 61%82%37%24%45% Percentage of occupied hours below 21 o C 23%6%63%69%50% Strong contrast between the indoor temperatures in office F10 and others. Office F10 is electrically-heated while other offices heated through radiators connected to the gas boiler. Electric storage heater in office F10 was continuously on during monitoring period. Gas boiler heating system even ran during unoccupied periods such as night-time and weekends. CO 2 levels (1200 ppm) tend to be higher than desired in office F13.

36. Thermal imaging surveys Heat loss through white pained wall

37. Feedback from occupants Occupants feel cold in winter and hot in summer; Temperature varies during day in summer; Air quality is draughty, smelly and stuffy in winter; Low overall satisfaction in both winter and summer; Occupants comment: ‘The heat is never stable. It is either too hot or too cold.' ‘Some area is warmer than others’.

38. Predicting post-refurbishment building performance

39. Predicted energy savings kWh/m 2 11% 49% 55%

40. Post- refurbishment BPE

41. Post-refurbishment BPE methodology (May 2014 - May 2015) Review of handover process and commissioning Fabric performance: air-permeability, thermography Remote monitoring of energy use, environmental conditions (external and internal) and occupant interaction with windows Occupant satisfaction survey using BUS questionnaires Technical review of building and equipment performance Review of the performance and usability of controls Structured interviews with management

42. Remote monitoring of energy use and environmental conditions

43. Remote monitoring systems Energy use (gas and electricity) and sub-metering (5-min data start from 11/04/2014) Moisture levels in fabric (5-min data start from 25/03/2014) Temperature, relative humidity (5-min data start from 18/04/2014) Indoor CO 2 levels as proxy for indoor air quality (5-min data from 26/04/2014) Open-close window sensors (from 26/04/2014) Heating usage behaviour using i-buttons on radiators (15-min data start from 26/04/2014)

44. Monitoring following data in every 5-minute Total gas usage Total electricity usage Electricity usage of MVHR and 2 electric water heaters Heat output from boiler for space heating Heat meter and transmitter Sub- electricity meter and transmitter Electricity meter and transmitter Gas meter and transmitter Energy metering and sub-metering

45. Moisture monitoring systems

46. Environmental monitoring systems CO 2 logger Temperature/RH sensor Solar radiation sensor Temperature/RH logger

47. Behaviour monitoring: window opening and heating usage Temperature logger on radiator Windows opening logger

48. Innovative Refurbishment Garth House 10 th June 2014 Bicester Town Council