RESIDENTIAL RETROFIT. Chris Grady & Michael Slevin. Supported by William Scott

Transcription

1 RESIDENTIAL RETROFIT Chris Grady & Michael Slevin Supported by William Scott

2 RESIDENTIAL RETROFIT Programme Introduction Building Regulations TGD L Dwellings Case Study 1-4 Bed Semi, Deep Retrofit Case Study 2 ESB HALO 3 Bed Semi-D Case Study 3 DEHLG 2010 Energy Efficiency Programme SEAI Schemes and Grants Opportunities for QS 2

3 INTRODUCTION Improved energy performance the drivers Source DoECLG 3

4 INTRODUCTION Primary Energy Related CO2 by Sector, Source: SEAI annual report

5 INTRODUCTION A progression to low / zero carbon housing Easy challenging very difficult New attitude + new knowledge + more tools + heightened diligence Reduced demand for energy + increasing use renewables diligence Source DoECLG 5

6 Building Regulations TGD L Dwellings Technical Guidance Document Part L 2011 Some transitional arrangements to Nov 13 Applies to Newly constructed dwelling Window door and boiler replacements in existing dwellings New extension to existing dwelling Existing dwelling undergoing material alteration Existing building undergoing change of use to become dwelling(s) Protected structures are exempt 6

7 TGD L 2011 Section 0: General guidance Application - New Dwellings 1. Whole dwelling performance (MPEPC, MPCPC) 2. Component minimum performance levels (backstop) Renewables Fabric insulation Air permeability Boiler efficiency Building services controls Insulation pipes, ducts, vessels Mechanical ventilation Performance of completed building 3. User Information We look at these in sequence. 7

8 TGD L 2011 Section 1: New dwellings Whole Dwelling Performance Limits on primary energy and CO 2 (DEAP) Maximum Permissible Energy Performance Coefficient MPEPC 2011 = 0.4 (60% reduction on 2005 regs dwelling) Maximum Permissible Carbon Performance Coefficient MPCPC 2011 = 0.46 (54% reduction on 2005 regs dwelling) Use of backstop / minimum elemental standards in TGD will not meet maximum permissible performance coefficients for primary energy and CO 2 Be sure you meet your MPPCs before you start building! 8

9 TGD L 2011 Section 1: New dwellings Renewable energy 10kWh/m 2 water or space heat or 4kWh/m 2 electrical energy using Solar thermal PVs Biomass/biofuels Heat pumps Wind etc. Combined heat and Power (CHP) Installers must be FETAC (or eq) qualified in the technology CIF IGBC TGDL 2011 William Scott 9

10 TGD L 2011 Section 1: New dwellings Building Fabric - U-values improved 20 25% CIF IGBC TGDL 2011 William Scott Superseded

11 TGD L 2011 Section 1: New dwellings Building Fabric Thermal Bridging Specific compliance options Use Acceptable Construction Details Appropriate Y factor for DEAP = 0.08 or Use details from ACDs and / or other certified details (using modelling software IS EN ISO compliant) for all key junctions and Calculate transmission heat loss coefficient Htb using ψ values for ACDs as detailed in App D or for other certified details CIF IGBC TGDL 2011 William Scott 11

12 TGD L 2011 Section 1: New dwellings Building Fabric Thermal Bridging - Background Y value is critical, for example: DEAP A3 dwelling Typical opaque elements U-value ~ 0.14 If Y= 0.02, corrected U = 0.16 If Y= 0.08, corrected U = 0.22, BER is worse by 13% If Y= 0.15, corrected U = 0.29, BER is worse by 30% Y value also increases U-value of glazed openings and doors (Good TB detailing is free, PH standard ~ cost + 1.5%) 12

13 TGD L 2011 Section 1: New dwellings Building Fabric Air Permeability Permeability is relevant to entire building envelope Max 7m 3 /(h.m 2 ) under q 50 test (accredited tester) Methodology (Define required performance, big benefit DEAP if lower permeability achieved; heat load down by 30 75%) Identify air barrier elements, VCLs, breathers Use ACDs or better details and specify, communicate to those involved in construction Responsibility for construction of details should be established. QA regime / procedures / air-tightness tests to meet goal 13

14 TGD L 2011 Section 1: New dwellings Building Services Hot water storage vessels, pipes, ducts Hot water storage tanks get 50mm factory applied PU foam (30kg/m 3 ) or eq Pipework insulation All heating pipes insulated to specified standard unless directly contributing useful heat to space Primary circuit (boiler to tank) insulated All hot pipes connected to hot water storage tank to be insulated for minimum 1m from connection to tank Insulation to attic tank / pipes noted 14

15 TGD L 2011 Section 1: New dwellings Building Services - Boilers / heating Refer to the HARP database Gas or oil boilers, hwch > 90% seasonal efficiency Condensing boiler technology Biomass boiler, hwch > 77% seasonal efficiency Effective control of space and water heating Thermostat and separate time control space heating Thermostat and separate time control stored water heating Interlock to boiler or eq no demand, no activity Small dwellings also can use TRVs Dwellings >100m 2 need 2 or more heat zones with separate time and thermostat controls. 15

16 TGD L 2011 Section 1: New dwellings Construction Quality, Commissioning of Services Reasonable QA measures during construction Checks & assessments at completion to ensure compliance and design aims are met All to be aware of importance of envelope integrity Provide user with sufficient information to allow fuel / energy efficient operation The building Fixed building services, maintenance» O&M Manuals specific to system» Time and temperature settings» Routine maintenance Air permeability result 16

17 TGD L 2011 Section 2: Existing dwellings Applies to existing dwellings Extensions Change of use to a dwelling Material alteration Sets minimum performance levels for components Fabric insulation Extensions Table 1 (as new build) Material alterations, Change of use Table 5 Thermal bridging Diagram 2 and ACDs Air permeability No test ACDs and Diagram 3 Boiler efficiency as new build Building services controls as new build Insulation pipes, ducts, vessels as new build Windows generally U-value <

18 TGD L 2011 The effect on practice & procedure Brief / Design Establish energy and BER targets Allocate budgets Agree both with client Design smart for energy use orientation, form, opes, technologies Detail design / tender Set lines of VCL, insulation Comprehensive details, robust, continuous, buildable, maintainable If you don t have detail drawings, you cannot price it or build it! Comprehensive specification Allocate design and construction responsibilities Construction Site training, briefing, inspection, review, commission and test 18

19 Case Study 1-4 Bed Semi, Deep Retrofit 210sqm 1930s extended semi-d refurbished in 2010 The fabric The services The DEAP and real life results 19

20 Building Fabric Improvement Workshop - As Built Case Study Concrete floor on insulation, U-value U

21 Building Fabric Improvement Workshop - As Built Case Study MAIN ROOF quilt, U-value U =

22 Building Fabric Improvement Workshop - As Built Case Study EWI U-value U = 0.14 Cold bridges very limited 22

23 IWI U-value U = 0.25 Cold bridges Building Fabric Improvement Workshop - As Built Case Study 23

24 EWI takes out a lot of cold bridges Insulation continuous from wall to flat roof and on to wall again Beams are under insulation 24

25 Triple glazed windows to rear U-value 1.0 Doors U-U value 0.85 Double glazed windows to front U-value 1.4 No rooflights to prevent heat loss at shaft Building Fabric Improvement Workshop - As Built Case Study 25

26 lobby AIR TIGHTNESS = 0.139ACH Building Fabric Improvement Workshop - As Built Case Study Block 3 chimneys = Duct to room-sealed wood stove Blank duct to future enclosed fire, currently open fire with closing damper lobby 26

27 AIR TIGHTNESS Sealed and insulated trapdoors, sealed to ceiling membrane 27

28 Infiltration ~ ac/hr Mechanical Ventilation with Heat Recovery (MVHR) 1.25W/(l/s) 82% exchanger efficiency Rickaby Thompson Associates Scott+MacNeill 28 28

29 Solar water Raised it to maximise sunlight after Sketchup exercise Aperture area = 3m2, Zero loss efficiency = 0.83, Heat Loss Coeff =1.14 Bird protection and joint insulation snagged later 29

30 Water heating: Building Fabric Improvement Solar for 8 Workshop months backed - As Built Case Study up by gas boiler, 75mm factory insulated tank Tight distribution minimum dead legs Water conservation taps 30

31 SPACE HEATING Building Fabric Improvement Gas Workshop condensing -boiler As Built 91% Case efficient Study 5 zoned timers, thermostats and 100% rads have TRVs Enclosed room-sealed wood burning stove in kitchen has ducted air supply 31

32 LIGHTING 95% low energy, FL, CFL or LED No recessed downlighters at first floor 32

33 TOTAL HEAT LOSS = 190W/K CO2 To keep house at 20C when external temp is say 5C needs 15 (K difference) x 190 = 2.85kW - much of this comes from occupancy, lighting and appliances Main Space Heating System = 728 kg/yr Secondary Space Heating System = 14 kg/yr Water Heating System = 538 kg/yr Pumps and fans = 691 kg/yr Renewables = 0 Total 2559 kg/yr BER A3 (was G originally) Energy = 66.1 kwh/m2/yr CO2 = kgco2/m2/y DEAP year DEAP kwhr Metered kwhr Euro (2011) Space Heat 4150 Water heat 2652 Gas Electric pumps, fans, lights (incl cooking & appliances) 33

34 Case Study 2 - ESB Halo 3 Bed Semi-D HALO was a free independent home energy survey which ESB Energy Services' offered to homeowners. Developed to support Ireland's 20% energy reduction target by Consisted of a home energy audit followed by an assessment of energy saving proposals Homeowners were issued a report outlining energy saving recommendations, estimated capital costs, payback periods and carbon savings. 34

35 Case Study 2 - Survey Process Survey assessed energy efficiency and proposed upgrades of : Attic Insulation Rafter Insulation External Wall Insulation Cavity Wall Insulation Internal Wall Insulation (Dry Lining) Boiler Efficiency Heating Controls Lighting Air Tightness Sample Halo Survey-cavity KSN ENERGY R2 xls.pdf 35

36 Case Study 2 - ESB Halo 3 Bed Semi-D 36

37 Case Study 2 - ESB Halo 3 Bed Semi-D 37

38 Case Study 2 - Recommendations 38

39 Case Study 2 - Paybacks 39

40 Case Study 2 - Recommendations 40

41 Case Study 2 - Recommendations 41

42 Case Study 2 - Recommendations 42

43 Case Study 2 - Recommendations 43

44 Case Study 2 - Recommendations 44

45 Case Study 2 - Data Collection 45

46 Case Study 2 - Data Outputs 46

47 Case Study 2 - Summary Overall Summary: Potential Energy Savings : 579 per yr. 1,821 KgsCO2 per yr. 47

48 Case Study 2 - Conclusion Consistency of advice to public is required to create trust in the market Sample Halo Survey-cavity KSN ENERGY R2 xls.xlsx Incentive to try to stimulate the market Good public feedback and appreciation Role is suitable to an experienced or upskilled surveyor 48

49 Case Study 3 DEHLG 2010 Energy Efficiency Programme Conducted pre-works BER report & resultant BER on behalf of Local Authorities Consisted of the following: Conduct pre-works BER survey Input data on DEAP software Calculates actual energy value Enters perceived upgrade works to achieve improved BER Each report is bespoke to take into consideration individual tenant needs Report is generated and issued to engineer Once upgrade works are finished a revisit is required to verify works are complete Engineer is advised of findings / snags Upon satisfactory completion a post works BER is conducted and certificate produced

50 Proposal under DEHLG 2010 Energy Efficiency Programme (Worked Example) Property address: 66 St. Patrick's Park, Springfield, Co. Cork Description of property: 2 storey, 3 bedroom, end of terrace Gross internal floor area: 82 sq. m. Year of construction: 1982 Current energy rating: 350 kwh/m2/year Current BER Rating: E2 Current heating source: Oil-fired boiler, 70% efficiency New BER Rating: C1 Step Proposed Interventions Add 250mm additional glass fibre insulation to the attic Inject full fill cavity wall insulation to all external walls Install 100% low energy fixed lighting bulbs (10 no. light fittings) Replace existing boiler with high efficiency boiler (95%). Revised Energy energy saving rating (kwh/m 2 /yr) (kwh/m 2 /yr) Annual energy saving (kwh/yr) Fuel cost per kwh ( uro) 1 Energy savings per annum ( uro) Capital cost ( uro) 2 Payback period (years) , , , , , Provide TRVs to all radiators (8 no. ) , Adapt existing pipework and controls to provide independent service to hot water cylinder Replace hot water storage cylinder with factory insulated cylinder , Replace existing single-glazed windows with double-glazed units - 8 no. in total , , Draught-proofing measures to reduce air changes per hour , Insulate primary pipework Notes: Totals: 1,073 17, Energy costs available from the SEI website. For the purposes of this example, gas oil is costed at and electricity is costed at per kwh. In the case of Intervention No. 6 it is assumed the the enegy saving is 50% gas oil and 50% electricity and therefore the energy cost is assessed at half the total of the cost of both energy sources. 2 Capital cost to include VAT on construction costs and design/management costs. 3 The approach to calculating the payback period is simple, in that it does not take account of future costs in terms of inflation/discounting. However, it is sufficient for the purpose of identifying the most cost-effective interventions. 4 Though the payback period for replacement windows is difficult to justify in its own right, when combined with the other proposed interventions an overall payback period of 15 years is achieved. 5 Cells coloured 'green' require user input; cells coloured 'yellow' are automatically calculated

51 Proposal under DEHLG 2010 Energy Efficiency Programme Property address: 15 Foyleview Crescent, Moville Description of property: 3 Bed Semi detached House. Gross internal floor area: sq. m. Year of construction: 1997 Current energy rating: kwh/m2/year Current BER Rating: F Stanley S/F Range Cooker c/w Integral Boiler Current heating source: & Open S/F Fire. New BER Rating: B2 Step Proposed Interventions Install new (OFCHS) complete with; new oil condensing boiler (95%) Seasonal Efficiency (Source HARP Database), new 3 channel 7 day programmer, 2 room thermostats (1 Upstairs & 1 Downstairs) and TRVs fitted throughout (3 zones - 1 DHW & 2 Space Central Heating). Install new 50mm thick factory insulated cylinder; fit new hot water cylinder thermostat complete with fully insulated primary pipework to hot-press areas upstairs & downstairs with close attenetion to well taped cosy wrapping on all knuckle joints & wire for boiler interlock also. (C1 Achieved) Remove range cooker to kitchen blocking off open flue permanently; Fit new (75%) (Source HARP Database) Seasonal Efficient Multisolid fuel stove or fire insert stove in place of open fire to living room as room heater only, whereby converting chimney to open flue. (C1) Top up attic insulation from 100mm to 300mm overall depth. Attic door also to be insulated & fully draught stripped. (B3 Achieved) Pumped top-up Insulation to cavity walls achieving a new U-Value of 0.29 W/m2K or better (Certified) ( B3) Installing solar water heating system min 3.20 m2 of aperature area of evacuated tube solar collector Thermomax HP 400 (30) O.E.A to South West Rear facing roof at 30 degree pitch and new max 300 L combined factory 50mm insulated hot water cylinder with solar part one third of total volume for contribution to DHW. (Full certified data specification in accordance with IS EN required upon completion) (B2 Achieved) Energy saving (kwh/m 2 /yr) Revised energy rating (kwh/m 2 /yr) Annual energy saving (kwh/yr) Fuel cost per kwh ( uro) 1 Energy savings per annum ( uro) Capital cost ( uro) 2 Payback period (years) , , , , , , , , Notes: Totals: 1,511 12, Energy costs available from the SEI website. 2 Capital cost to include VAT on construction costs and design/management costs. 3 The approach to calculating the payback period is simple, in that it does not take account of future costs in terms of inflation/discounting. Howev identifying the most cost-effective interventions. 4 Cells coloured 'green' require user input; cells coloured 'yellow' are automatically calculated 51

52 SEAI Grants and Schemes Better Energy Homes Scheme grants Energy Efficient Works Incentive Cash Grant Value Insulation Attic Insulation 200 Wall Insulation - Cavity 250 Wall Insulation - Internal Dry Lining Apartment (any) OR Mid- terrace House 900 Semi-detached or End of Terrace 1,350 Detached House 1,800 Wall Insulation - External Apartment (any) OR Mid- terrace House 1,800 Semi-detached or End of Terrace 2,700 Detached House 3,600 Heating System Heating Controls with Boiler (Oil or Gas) Upgrade. 560 Heating Controls Upgrade only 400 Solar Heating 800 Building Energy Rating (BER) 50 52

53 SEAI Grants and Schemes Warmer Homes Scheme works The service involves the installation of standard energy efficiency measures appropriate to the eligible household subject to SEAI survey, budget allocation and available capacity. The service is provided at no cost to the household and the measures currently available under this scheme are: -Attic insulation. -Draught proofing. -Lagging jackets. -Low energy light bulbs. -Cavity wall insulation. -Energy advice. 53

54 Opportunities for QS BER s QS Services for Deep Retrofit Projects Energy Surveys & BER for Local Authorities Project Management Life Cycle Costing Measurement of Embodied Energy (Carbon) measure Summer Schools work Energy Upgrades 54

55 RESIDENTIAL RETROFIT - QUESTIONS? Chris Grady, Michael Slevin William Scott