Presented by: John Hockman B.E.S. JLHockman Consulting Inc. With many thanks to Harold Orr, Rob Dumont, Gary Proskiw and Anil Pareckh 2012

Size: px

Start display at page:

Download "Presented by: John Hockman B.E.S. JLHockman Consulting Inc. With many thanks to Harold Orr, Rob Dumont, Gary Proskiw and Anil Pareckh 2012"

Noreen Walters
6 years ago
Views:

1 Presented by: John Hockman B.E.S. JLHockman Consulting Inc. With many thanks to Harold Orr, Rob Dumont, Gary Proskiw and Anil Pareckh 2012

2 Presentation Objectives: Review past design concepts and technologies from residential construction on the Prairies (Manitoba), and lessons learned from a range of projects; Review opportunities to improve energy and environmental performance of buildings; What support can be provided to the construction industry to help propagate Best Practice ideas to assist meeting the goals and requirements of 9.36 and MNECB

3 The 1970 s oil crisis spawned a whole range of energy efficiency responses for construction and renovation of housing. Sadly many of these lessons have been forgotten or ignored over the last 25+ years. 3

4 The initial steps taken to reduce residential energy usage started with passive solar dwellings in the USA. 4

5 Direct Gain Passive Solar heating. Using common building components such as south facing windows and thermal storage in the home s ceilings, walls and floors to capture useful space heating became popular in USA. The Trombe wall was also a popular version of Glass and Mass approach (without insulated shutters and air check valves, high night time heat losses occurred.) 5

6 In the US there was push to maximize Passive Solar heating - GLASS & MASS Roughly 30% ratio of south glass to floor area. David Wright House in Santa Fe, New Mexico,

7 The Problem with too much glass: 1. Severe overheating, particularly in the spring and fall, but also in the summer. The Santa Fe house shown on the opening slides would swing 20 degrees F (11 degrees C) on a sunny day in January even though the house had a lot of (tons of) thermal mass because the heat from the solar energy is unable to get into and out of thermal mass fast enough. 2. It s expensive - windows are quite costly compared with walls (in Low rise residential). 7

8 So, probably not the best way to go (at least until smart windows and workable insulated shutter systems.) VERY high peak heating loads at night, and VERY high cooling loads during day. (Note the lack of shading of lower windows) 8

9 So how much South window can be used to maximize passive gains without cooking the occupants in light wood framed housing? We know that any window, double glazed or better, facing within 30 degrees of true south will be a net heat gain over the heating season in most of the Prairies so let s maximize that gain! Prairie experience now suggests that if the ratio of the south window area to the floor area is less than about 6% to 8%, no additional thermal mass is needed because there is enough heat storage in the house wood materials and gypsum board already. So where did this % number come from? 9

10 Saskatchewan Conservation House-1977 (a past model for the present?) The engineering concepts, not necessarily the style. LIGHT(weight) and (air)tight Construction. (one of the influences on passivhaus) 10

129) TG Vinyl windows (before low e was available) Air tight

11 Private Manitoba Home also 1977 (based on many of concepts in Sask. House) Double walled (R44 RSI 7.75 U = 0.129) TG Vinyl windows (before low e was available) Air tight construction details Small North window area Well shaded E & W windows 11

12 Private Manitoba Home Passive solar 8% S window area Home built solar air collectors Solar greenhouse on Living Room 12

13 75 plus Super-insulated Private Homes in NW Ontario, Manitoba and Saskatchewan mostly rural Standard wall construction with refinements, Special foundation details for Preserved Wood Foundations basements and crawlspaces. 13

14 Foundation detail to reduce lost floor area Floor joists & sub-floor is expensive part of floor system; Place sill plate on interior face of concrete wall and make wall additional 6.5 inches longer on exterior; Inner wall is load bearing; Many different ways to build double wall. 14

15 Lessons learned: 1. Energy modeling (with HOTCan) was important to determine energy saving impact of various conservation measures; 2. Modeling showed that basement floor heat loss was significant when upper envelope was well insulated; 3. Airtightness is critical BUILD TIGHT AND VENTILATE RIGHT many hand built HRVs; 4. Public support was high with seminars filling 300 seat theatres for public info sessions. 15

16 The interest in solar homes resulted in the arrival of books and magazines and the NRCan AIR/VAPOUR BARRIER Manual. 16

17 R2000 Standard hit the scene in Research Homes in Transcona, Winnipeg built between 1984 and 1989 It was possible to make Production Homes efficient. 17

18 Research and more research in 1980 s 18

19 Mechanical systems research 19

20 Super-insulated Public Housing? Manitoba Housing built many single unit, semi-detached and row house units in 1980 s in Manitoba using standard details. Note thick walls at windows, windows in interior of double wall and sloped exterior sill. 20

21 Lessons learned: 1. Lots of mechanical alternatives: Heat pump heat recovery ventilation, Heat pump DHW, tall electric DHW tanks gave good stratification. 2. Mechanical systems can get very complicated very fast, and often with no one that knows how to maintain them; 3. Production Builders could build the envelope consistently once trades learned the key things that they had to do differently. 21

22 Advanced Houses research in 1993 TARGET was to use 50% less energy than a R2000 Home. Plus Water, IAQ, Materials, and Healthy home goals. Manitoba Advanced House other Advanced Houses across Canada Lots of research on these homes 22

23 Advanced Houses research in

24 Advanced Houses research in 1993 One of first Direct Vent Natural gas fireplaces with electronic ignition Natural gas refueling station Visitable access walkway 24

25 Lessons learned: 1. Keep Mechanical systems as simple as possible; 2. Zoning is not as great a benefit in houses/buildings with highly efficient envelopes, the temperature is fairly even throughout even with single heat source each floor; 3. Pilot lights on fireplaces may use up to 20% of energy in energy efficient houses; 4. The Natural gas compressor station used so much electric energy, the car was basically an electric car. 25

26 Dumont Residence, Saskatoon, 1992 South window to floor area ratio = 5.5% Passive solar that works -almost no overheating; only extra thermal mass is scrap gypsum board in the interior walls. Note shading of upper windows in summer by roof overhang. 26

27 Dumont Residence, Winter Note the lower sun angle and absence of shading on the windows (likely one of most efficient homes in N America when built) 27

28 How much thermal mass inside the home will be used? South window area can be increased if the house has additional thermal storage. Inexpensive thermal mass can be scrap gypsum board placed inside the interior stud walls. Other thermal mass options are concrete floors, scrap gypsum placed in the floor cavities. (Be careful about additional structural loads.) 28

29 Space Heating (kwh) Dumont House - As Built (MB average home uses 16,000 kwh) Upper Line Light, wood frame, construction with Triple paned, low-e, argon filled, windows South Window Area / Heated Floor Area [%] 29

30 Space Heating (kwh) High Performance Windows and Vary the Mass what benefits Light (wood frame) construction (0.060 MJ/Km 2 ) Medium (thick walls) construction (0.153 MJ/Km 2 ) Heavy (masonry) construction (0.415 MJ/Km 2 ) Very heavy (concrete) construction (0.810 MJ/Km 2 ) South Window Area / Heated Floor Area [%] 30

31 Thermal Mass Ideas 1. Large interior masonry (feature) wall 2. Concrete floor 3. Thicker gypsum 4. Thick walls, filled with scrap gypsum 5. Thick walls, filled with scrap steel 6. Thick walls, filled with water (watch where you hang the pictures!!!) Adding thermal mass to standard wood frame construction adds extra costs and this cost /benefit MUST be evaluated. 31

32 Private Advanced Home Wpg. TARGET 50% less energy usage than a R2000 Home (achieved 40%), plus environmental and IAQ goals, 2 different types of low e coatings and fiberglass frames used. Air Changes per 50 Pascals, Very high % South glass area but concrete radiant floors and steel construction throughout = no overheating. 32

33 Summary Passive Solar Design Guidelines 1. Windows should be concentrated as far as possible on the south facing wall to 8 %, percentage of south window area compared to heated floor area suggested in the past. 3. South window area can be increased if the house has additional thermal storage. 4. Summer overheating must be addressed. 33

34 Tadoule Lake School Energy TARGET was CBIP 25% less than 1997 MNECB 34

less energy usage than 1997 MNECB, Modeling was difficult

35 Mishkeegogamang School NW Ont. Met Commercial Buildings Incentive Program target of 25% less energy usage than 1997 MNECB, Modeling was difficult DOE 2 crashed if you had more than 100 windows architects like many little windows it seems 35

36 MEC Retail Outlet - Winnipeg 2 left side buildings deconstructed Right side building redeveloped 36

37 MEC Retail Outlet - Winnipeg CMHC thinks this building may have greatest % of on-site recycled content by mass at over 85% 37

38 MEC Commercial Retail Outlet Met the Commercial Buildings Incentive Program target of 25% less energy usage than 1997 MNECB 38

Used radiant floor heat and radiant overhead cooling, only air movement was

39 MEC Commercial Retail Outlet Met the C2000 Program Target of 50% less energy usage than ASHRAE 90.1, plus additional environmental and water usage goals. Used radiant floor heat and radiant overhead cooling, only air movement was ventilation air, very great reduction in distribution energy usage. Radiant floor system Cooling trough fixtures 39

40 Lessons learned: 1. Keep Mechanical systems as simple as possible; 2. Zoning is not as great a benefit in houses/buildings with highly efficient envelopes, the temperature is more even throughout; 3. Heating and cooling with fluid distribution rather than air saves significant electrical energy; 4. Reducing embodied energy and making buildings easy to recycle in the future should be a goal for all building construction. 40

41 Optimizing Energy Conservation Measures (ECMs) How does one decide How Much is Enough?, or to put it another way, How does one optimize and select the most cost effective measures to use to build a NBC 9.36 / MNECB / Equilibrium / NetZero building? 41

42 Cost Optimization Getting the most bang for your buck. The process of selecting Energy Conservation Measures (ECM s) and renewable options based on their costs and performance such that the incremental cost of upgrading the house to NZEH performance is as small as possible. Therefore, we need performance metrics to evaluate the various options

43 Performance Metric #1 Energy Conservation Measure (ECM) Value Index = (Incremental cost of the ECM) (annual energy savings) = $ / (kwh/yr) In other words, it is the cost of installing an ECM which will save 1.0 kwh per year. 43

44 Performance Metric #2 PV (PhotoVoltaic) Value Index = (PV System Cost) / (annual energy production) = ($/W) / (kwh/yr W) = $ / (kwh/yr) Substitute the current (2008) PV System Cost ($9/W) and performance (1100 Wh/yr per W in Winnipeg) to get the cost to generate 1.0 kwh per year. (NOTE: 2012= $4.75/W) = [(9 $/W) / (1100 Wh/yr W)] = $8 per kwh/yr In other words, the cost of installing a PV system capable of producing 1.0 kwh/yr would average about $8. 44

45 E C M V a l u e I n d e x ( $ / k W h / y r ) How do you decide How Much is Enough, or which is the best investment? 20 Typical ECM Value Indices Winnipeg, Medium-Sized House Use Photovoltaics PV Value Index 5 Use Energy Conservation A look at 12 typical ECM Upgrades in New Home construction 45

46 Using solar PV cells to do double duty, such as providing a solar PV laminated glass roof on a sunspace may change the cost and Value Index. 46

47 How do you decide much energy can be saved with energy modeling. 47

48 How do you decide much energy can be saved with energy modeling-many runs. 48

49 Modeling can also help predict how much Passive Solar Utilization will occur. Can be up to 50% with added thermal mass 49

50 Determining optimum level of Energy Conservation Measures Based on the Value Index and many, many, many energy simulation runs done at initial design stage, one can: - optimize the building envelope, appliances, lighting, hot water and other conservation measures, and - develop some general guidelines: 50

51 GENERAL GUIDELINES What it takes to build LIGHT and TIGHT NetZero Equilibrium type homes in very cold climates? 1. Select optimum form and orientation for a given site (elongated 1.5 to 1.0 in E & W axis, +/- 10 degrees of South-best if is slightly East). 2. Minimize shell or envelope heat loss with major (massive) insulation levels and very airtight construction (0.5 Air Changes per Hour or less). 3. Use only very efficient windows. 4. Use very efficient LAME (Lights, Appliances and Miscellaneous electricity users). 51

52 What does it take to build LIGHT and TIGHT NetZero Equilibrium type homes in very cold climates? ---- continued. 5. Reduce Hot Water usage through efficient appliances, showers and faucets; use drain water heat recovery and re-use grey water. 6. Use a Heat Recovery Ventilator with an effectiveness of 0.8 or higher with energy efficient motors (installed and balanced properly). 7. Maximize Passive Solar Gains (6%-8% rule unless thermal mass is added.) 8. Allocate space for solar photovoltaic panels and possible solar water heater panels (future installation). 52

53 City Planning Requirements: 1979 California sub-division realignment to maximize solar access without sacrificing number of lots, We still build subdivisions without solar access planning, and we need higher density development. 53

54 Primary Lessons learned: 1. We have most of the tools needed to build more efficient houses and buildings we DO NOT need any New and Improved Magic Bullets. 2. Production builders can build better envelopes on a repeated basis first effort into better performing envelopes (airtight please); 3. Maximize passive solar 35% minimum goal, and with planning layouts for solar; 4. Simple mechanicals with Heat Recovery on Ventilation Air and Drain Water (controls); 5. Use Value Index approach to evaluating optimum approaches to mix of envelope and other improvements; 54

55 Assistance to the Construction Industry on Energy Codes: 1. The majority of construction changes required to meet NBC 9.36 and MNECB have been proven in Canada over the last 25 to 30 years. 2. The Changes required could be applied tomorrow, but with all the diversity of options, industry would benefit if provided/shown how to use better tools to optimize choices; 3. Provision of Best Practice Guides and examples are needed there are many, many examples already if there were not, how could Habitat for Humanity build 32 LEED Platinum Homes (cert. in process) if the knowledge and tools were not already available; 55

56 Assistance to the Construction Industry on Energy Codes: 4. Implement a Build Canada program, similar to Build America program where Building Science/design/engineering Teams assist production builders to optimize their delivery of Energy Efficient homes; 5. There will be probably only 2 years before some provinces adopt the Energy provisions of Section 36 and MNECB Ontario just introduced it s own version of the Energy requirements that is the time line; 6. Bundle all existing IRC/NRCan/CMHC research lessons for easy consumption/links; 56

57 Acknowledgments: Harold Orr, retired from NRC, Rob Dumont, Dumont and Associates, Gary Proskiw, Proskiw Engineering, Anil Pareckh, CANMET, NRCan Urban Ecology Project, Winnipeg Housing and Rehabilitation Corporation, Prairie Architects, PSA Architects 57

Sapporo Net-Zero Energy Home Hokkaido, Japan. Description. Setting. Super E Canadian Member. Super E Japanese Member. Super E Case Study

Sapporo Net-Zero Energy Home Hokkaido, Japan Description The first Super E net-zero energy house was built by the oldest Super E partnership. Tsuchiya Two-by and K. Ito and Associates constructed the very