Eden Mills Community Hall York Street Eden Mills, ON

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Engineering Limited 650 Riverbend Drive Kitchener, ON N2K 3S2 tel:

1 Eden Mills Community Hall York Street Eden Mills, ON Energy Audit For Eden Mills Going Carbon Neutral 22 April 2009 Prepared by Enermodal Engineering Limited 650 Riverbend Drive Kitchener, ON N2K 3S2 tel: fax: web site:

2 Eden Mills Community Hall Energy Audit prepared for Eden Mills Going Carbon Neutral 22 April 2009 Richard Lay, P.Eng., Christianne Aussant Enermodal Engineering Page i

3 Index Introduction 1 Description of Building 1 Construction 2 Mechanical Equipment 4 Energy Use 4 Blower Door Test 5 Energy Simulation Model and Results 8 Analysis of Energy Conservation Measures 15 Greenhouse Gas Reductions 25 Recommendations 26 Appendices A Energy Costs B Blower Door Air Leakage Test Results C Air Sealing Article D Heating Cost Comparison Enermodal Engineering Page ii

Introduction Enermodal Engineering Ltd undertook this energy audit for the Eden Mills Going Carbon Neutral Project, a project of Eden Mills Millpond Conservation Association, during the spring and

4 Introduction Enermodal Engineering Ltd undertook this energy audit for the Eden Mills Going Carbon Neutral Project, a project of Eden Mills Millpond Conservation Association, during the spring and summer of We conducted an inspection of the building, with particular attention to the mechanical system and building envelope. We performed a blower door test to depressurize the building and measure the leakiness of the building envelope. We created an energy simulation model to estimate the energy use by a various building functions and through the components of the building. Based on this information, we reviewed various possible building modifications and estimated how much they could reduce the annual energy use. The focus of this report is therefore on energy use and potential for reduction rather than on the physical condition of the building. Description of building Address: 108 York Street, Eden Mills ON N0B 1P0 Owner: Eden Mills and District Community Club Inc. Date of construction: early 1900s, with renovations and additions Gross Floor Area: 5,378 sq ft (502.6 sq m) including new stairwell solid brick building built in 1900 and renovated with an addition to the north for a stage upstairs meeting room, a second floor balcony addition for a small storage room overhanging the sidewalk along York Street and an exit stairway to the East, View from York St, showing wall construction, overhanging storage room Enermodal Engineering Page 1

The hall is used for community functions including meetings, entertainment, activities of community groups, and rented for various social functions. It is used most days of the week and year round.

5 The hall is used for community functions including meetings, entertainment, activities of community groups, and rented for various social functions. It is used most days of the week and year round. Main meeting, assembly and dance hall. Plaster on lath on brick walls. Operable double hung DG windows Construction stone foundation on bedrock slab on grade ground floor in a stone foundation walls at ground floor level, mortar plaster, drywall or wood finishing board solid brick walls at second floor level of original building, mortar plaster, plaster (This construction can be seen in the attic above the hall ceiling) 2x4 wood framed walls on additions peaked roof, framed on site, asphalt shingles and Enermodal Engineering Page 2

Older hall to right, Centennial addition to left Insulation: slab on grade floor none stone and brick walls none framed walls of back

6 Windows: vinyl frame, cleared double glazed sealed units, operable horizontal slider bottom sections. About 20 yr old in the main building. View from rear, showing framed addition on masonry block foundation View from parking lot. Older hall to right, Centennial addition to left Insulation: slab on grade floor none stone and brick walls none framed walls of back addition R12 ceiling of second floor hall approximately 4 inches of loose fill mineral fiber, placed directly on top of wood ceiling with no air barrier =>R15 Enermodal Engineering Page 3

Mechanical Equipment 2 high efficiency propane furnaces, 50,000 BTU/h output, nominal 94% efficiency, Bryant Model 350MAV048 100 ABKA B, nominal

2 split air conditioning units, DX coils in furnace plenums, Luxaire Model HABA F0365 outdoor units 1 150 L (40 gallon) electric storage tank

7 Mechanical Equipment 2 high efficiency propane furnaces, 50,000 BTU/h output, nominal 94% efficiency, Bryant Model 350MAV ABKA B, nominal cfm airflow. 2 split air conditioning units, DX coils in furnace plenums, Luxaire Model HABA F0365 outdoor units L (40 gallon) electric storage tank water heater, 3 kw Local exhaust fan in downstairs washroom Well water system: submersible pump, UV sterilizer Wastewater: on site septic tank and disposal bed 2 high efficiency propane forced air furnaces. Electric domestic water heater. Enermodal Engineering Page 4

8 Energy Use The Hall has reduced its consumption of electricity and propane over the last 3 years, as shown in Table 1 below. See also Appendix A. Table 1: Electricity & Propane Metered energy use EMCC fiscal year Electricity (kwh) Propane (L) The 2007 electricity use was 43 kwh/day over the whole year. However, Electricity use in the most recent period of 295 days from June 2008 to April 2009 was lower 38 kwh/d, showing a continuing reduction in use. This is comparable to typical household use in Eden Mills. Of this total, domestic hot water (DHW) accounts for 2.6 kwh/d (measured by run time meter over 354 days from April 2008 to April 2009). The total energy use intensity in 2007 was [15,130 + (5,362 x 7.06)]/502.6 = 105 kwh/sq m d. This is relatively low compared to other institutional buildings in Canada, partly because it is not occupied fulltime. Blower Door Test Building scientists agree that building envelopes should be airtight and ventilation should be at controlled rate and location. Uncontrolled leakage that varies with outdoor conditions (wind, temperature) does not benefit the durability of the building, occupant comfort or energy operating costs. A Minneapolis Blower Door was installed in the west exterior door to the parking lot and operated to depressurize the building to 50 Pa negative pressure. Fan air flow was measured at this and intermediate pressures in order to determine the equivalent leakage area of the building envelope according to normally accepted practice. Results are shown in Appendix B. Also, a number of air leakage paths were identified using a smoke pencil. Summary Results: Equivalent Leakage Area: sq m Normalized Leakage Area: 3.3 cm2/m2 Leakage Rate: 5.18 air changes per 50 Pa Enermodal Engineering Page 5

(New tight construction is less than 1.5 ACH @ 50 Pa) Normalized Leakage Rate: 3.75 L/s @ 75 Pa Estimated Leakage Rate at design conditions: 0.

9 (New tight construction is less than Pa) Normalized Leakage Rate: Pa Estimated Leakage Rate at design conditions: 0.9 ACH, Pa Comments: The building is extremely leaky and loses a lot of heat in winter through warm air escaping and cold air leaking in. In summer, air leakage imposes an additional load on the air conditioning. It is important to note that this air leakage is far in excess of what is required for acceptable air quality, approximately 7 L/s per person. Significant air leaks were identified in the following locations: 1. the entire ceiling of the second floor hall, which is constructed in of thin would tongue and groove boards fastened to the underside of the roof framing, with no air barrier. Most of the joints between the boards are very leaky and some joints are open enough to let the loose fill insulation fall through. In addition, there is no air sealing around the many electrical boxes, for example for the light fixtures that penetrate the ceiling. This is the main route through which the heated air from the building in the wintertime leaves the building and is lost to the outside. The condition of the roof framing and roof boards looked to be excellent despite its age, probably because of this huge amount of unintended and expensive ventilation during the wintertime. From the attic hatch, there was no visible moisture damage. There are also pipes which penetrate the wood ceiling near the attic hatch and which offer an unfortunately excellent route for air to leave the building. Ceiling of main hall is tongue and groove wood not airtight at all. Enermodal Engineering Page 6

Roof truss framing and loose fill attic insulation. No air barrier, but no rot. 2.

A storage closet off to the side of the stairway connects directly to an unsealed storage area and the

Door to storage attic Storage attic is ventilated to the outdoors. 3.

10 Roof truss framing and loose fill attic insulation. No air barrier, but no rot. 2. The stairway to the third floor trustee's office is a major leakage path. A storage closet off to the side of the stairway connects directly to an unsealed storage area and the outdoors. A huge amount of air was felt blowing through this location. Door to storage attic Storage attic is ventilated to the outdoors. 3. trustee's office: window, office closet, electrical receptacles in the walls, any other penetrations through the wall. There does not seem to be any air barrier in the wall and ceiling assemblies. Enermodal Engineering Page 7

4. Second floor doors to the small storage room over the sidewalk. some leakage but not too bad, considering these are not intended as exterior doors.

Kitchen exterior door is very poorly sealed, fits poorly in the frame, is uninsulated, and should be replaced 6. Exit door from hall to new exit stairway has minor leakage.

11 4. Second floor doors to the small storage room over the sidewalk. some leakage but not too bad, considering these are not intended as exterior doors. The storage room addition itself is built relatively tightly. View from York St looking north Stairwell addition on east side, propane tank, chimney 5. Kitchen exterior door is very poorly sealed, fits poorly in the frame, is uninsulated, and should be replaced 6. Exit door from hall to new exit stairway has minor leakage. The stairway itself and exterior door was not examined. 7. Old back door to the parking lot is poorly sealed, fits poorly in the frame, is uninsulated and should be replaced. 8. Not examined: Mechanical room, adjacent storage room, Friendly Seniors meeting room. ENERGY SIMULATION MODEL In order to determine the effects of potential energy efficiency upgrades, an energy model of the Eden Mills Community Hall was developed using the following assumptions: Envelope: Table 1: Envelope Insulation Component R value Exterior Walls 6 Slab on Grade 1.5 Roof/Ceiling 16 Enermodal Engineering Page 8

12 Heating and Cooling: The heating system was modeled as a propane fired furnace with a nominal efficiency of 90%. The cooling system was modeled as a DX system with an EER =11. Heating Temperatures: occupied = 22 C, unoccupied = 15 C Cooling Temperatures: occupied = 24 C, unoccupied = 28 C Lighting: The lighting power was determined using fixture and wattage data provided. Occupancy Schedule: 3 days/wk: 7:00PM 9:30PM 3 days/wk: 9:00AM 11:00AM 1 day/wk: 10:00AM 11:00PM Energy costs Electricity: $ 0.15/ kwh Propane: $ 0.61 / litre BASE CASE MODEL: An energy model of the existing building was developed using the above assumptions. Tables 2 and 3 list the actual energy consumption of the Eden Mills Community Hall based on utility bill data (Appendix A), and the estimated energy consumption based on the energy model. Month Table 3: Actual and Estimated Electricity Actual Monthly (kwh/month) Electricity Simulated Monthly (kwh/month) Percentage Difference JAN % FEB % MAR % APR % MAY % JUN % JUL % AUG % SEP % OCT % Enermodal Engineering Page 9

13 NOV % DEC % TOTAL % There are considerable differences between the actual and estimated electricity consumption for some months. This is likely due to differences in the actual and assumed occupancy schedule and use patterns. However, the estimated electricity consumption is within 5% of the actual electricity consumption when compared on an annual basis Actual Estimated JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Chart 1: Actual and Estimated Electricity Table 4: Actual and Estimated Propane Propane Actual Annual (litres/year) Simulated Annual (litres/year) Percentage Difference % The actual and estimated propane consumption could not be compared on a monthly basis however; the estimated propane consumption is within 6% of the estimated value when compared on an annual basis. Enermodal Engineering Page 10

14 Litres Actual Estimated Chart 2: Actual and Estimated Propane Chart 3 illustrates the electricity end use break down. 12% 6% 15% 2% 59% Lighting Receptacles Cooling Pumps Fans DHW 6% Chart 3: Electricity End Use Breakdown (%) Enermodal Engineering Page 11

15 832 kwh 260 kwh 1795 kwh 2348 kwh 983 kwh 9065 kwh Lighting Receptacles Cooling Pumps Fans DHW Chart 4: Electricity End Use Breakdown (kwh) 60% 24% 2% 6% 5% 0.7% 2% Lighting Receptacles Cooling Pumps Fans DHW Space Heating Chart 5: Total Energy Cost End Use Breakdown (%) Enermodal Engineering Page 12

16 $3477 $1360 $148 $352 $39 $269 $125 Lighting Receptacles Cooling Pumps Fans DHW Space Heating Chart 6: Cost End Use Breakdown ($) Tables 5 & 6 list the UA value (imperial and SI) for the different building components, indicating their relative contribution to heat loss. Understanding where the majority of the heat is lost will help determine the best energy saving measures. Table 5: Building Component UA Values (Imperial Units) Component Area (ft 2 ) U value (BTU/hr ft 2 F) UA (BTU/hr F) Exterior Walls Windows Roof/ ceiling Floor & foundation Table 6: Building Component UA Values (SI Units) Component Area (m 2 ) U value (W/ m 2 K) UA (W/K) Exterior Walls Windows Roof Flr & foundation Enermodal Engineering Page 13

17 Table 7 lists the peak heating load components, on a building level. Table 7: Peak Heating Load Components Component Peak Heat Loss (kw) Percentage (%) Wall + Roof Conduction % Window Conduction 3.0 5% Floor and foundation Conduction % Infiltration % 18% 46% 5% Wall + Roof Conduction Window Conduction Foundation Conduction Infiltration 31% Chart 7: Peak Heating Load Components At peak conditions, infiltration is the largest contributor to heat loss, accounting for almost half of the total building heat loss. Enermodal Engineering Page 14

18 ENERGY CONSERVATION MEASURES (ECMs): Three basic conservation measures were modeled: 1. Increase insulation in walls and ceiling 2. Upgrade windows 3. Air seal the whole building (reduce infiltration) ECM 1: Improved Envelope Performance (Insulation) To reduce energy consumption, additional insulation can be added to the exterior walls and attic floor or roof. Table 8 lists the upgraded insulation levels: Table 8: Upgraded Envelope Insulation Component R value Exterior Walls 16 Slab on Grade No change Ceiling 28 Roof No change Tables 9 and 10 list the energy consumption using the upgraded insulation levels. Table 9: ECM1 Estimated Electricity Electricity Month Base Case Monthly (kwh/month) ECM1 Monthly (kwh/month) Percentage Difference JAN % FEB % MAR % APR % MAY % JUN % JUL % AUG % SEP % OCT % NOV % DEC % TOTAL % Enermodal Engineering Page 15

19 Table 10: ECM1 Insulation Estimated Propane Base Case Annual (litres/year) Propane ECM1 Annual (litres/year) Percentage Difference % Figures 9 and 10 illustrate the electricity and propane consumption for the Base Case vs. ECM kwh 1000 Base Case ECM JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Chart 8: Base Case and ECM1 (Insulation) Electricity Litres Base Case ECM1 Chart 9: Base Case and ECM1 (Insulation) Propane Enermodal Engineering Page 16

20 There is some electricity saving realized due to the decreased heating load resulting in fan energy savings. Table 10 shows that increasing the exterior wall R value to R 16 and the attic R value to R 28 results in a 37% reduction in annual propane consumption. It is possible however that the model underestimates the heat lost through the existing ceiling because of its leaky construction; increasing attic/roof insulation would therefore have a greater benefit than predicted here. ECM 2: Improved Window Performance Windows with better glazing can be installed to reduce heating energy. The upgraded windows used in this simulation are double glazed, argon filled, with low e coating (e3=0.1) and insulating spacers. Tables 11 and 12 list the energy consumption using the upgraded windows. Table 11: ECM2 Windows Estimated Electricity Electricity Month Base Case Monthly (kwh/month) ECM2 Monthly (kwh/month) Percentage Difference JAN % FEB % MAR % APR % MAY % JUN % JUL % AUG % SEP % OCT % NOV % DEC % TOTAL % Table 12: ECM2 Windows Estimated Propane Propane Base Case Annual (litres/year) ECM2 Annual (litres/year) Percentage Difference % Enermodal Engineering Page 17

21 Charts 10 & 11 illustrate the electricity and propane consumption for the Base Case vs. ECM kwh 1000 Base Case ECM JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Chart 10: Base Case and ECM2 Windows Electricity Litres Base Case ECM Chart 11: Base Case and ECM2 Propane As can be seen from Table 12/ Chart 11, improving window performance results in a 6% reduction in annual propane consumption. Enermodal Engineering Page 18

22 ECM 3: Reduced Infiltration This is a big one. Reducing the air infiltration from test values of 50Pa to the R2000 standard 50Pa is equivalent to reducing design rates at 5 Pa from 410 L/s to 200 L/s and gives significant energy savings. Tables 13 and 14 list the electricity and propane consumption assuming reduced air infiltration. Table 13: ECM3 Air seal Estimated Electricity Electricity Month Base Case Monthly (kwh/month) ECM3 Monthly (kwh/month) Percentage Difference JAN % FEB % MAR % APR % MAY % JUN % JUL % AUG % SEP % OCT % NOV % DEC % TOTAL % Table 14: ECM3 Estimated Propane Propane Base Case Annual (litres/year) ECM3 Annual (litres/year) Percentage Difference % Figures 13 and 14 illustrate the electricity and propane consumption for the Base Case vs. ECM3. Enermodal Engineering Page 19

23 kwh 1000 Base Case ECM JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Chart 12: Base Case and ECM3 air seal Electricity Litres Base Case ECM Chart 13: Base Case and ECM3 air seal Propane ECM 1 and 2: Improved Envelope and Window Performance Tables 15 and 16 list the electricity and propane consumption including both increased envelope and window performance. Enermodal Engineering Page 20

24 Table 15: ECM1&2 Estimated Electricity Electricity Month Base Case Monthly (kwh/month) ECM1&2 Monthly (kwh/month) Percentage Difference JAN % FEB % MAR % APR % MAY % JUN % JUL % AUG % SEP % OCT % NOV % DEC % TOTAL % Table 16: ECM1&2 Estimated Propane Propane Base Case Annual (litres/year) ECM1&2 Annual (litres/year) Percentage Difference % Charts 14 and 15 illustrate the electricity and propane consumption for the Base Case vs. ECM1&2 Enermodal Engineering Page 21

25 kwh 1000 Base Case ECM1& JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Chart 14: Base Case and ECM1&2 Electricity Litres Base Case ECM1& Chart 15: Base Case and ECM1&2 Propane As can be seen from Figure 16, improving both envelope and window performance results in 42% reduction in annual propane consumption. ECM 1, 2 and 3: Improved Envelope and Window Performance and Reduced Infiltration Tables 17 and 18 list the electricity and propane consumption including increased envelope and window performance and reduced infiltration. Enermodal Engineering Page 22

26 Table 17: ECM1,2 and 3 Estimated Electricity Month Base Case Monthly (kwh/month) Electricity ECM1&2&3 Monthly (kwh/month) Percentage Difference JAN % FEB % MAR % APR % MAY % JUN % JUL % AUG % SEP % OCT % NOV % DEC % TOTAL % Table 18: ECM1,2 and 3 Estimated Propane Base Case Annual (litres/year) Propane ECM1&2&3 Annual (litres/year) Percentage Difference % Charts 16 and 17 illustrate the electricity and propane consumption for the Base Case vs. ECM1&2 Enermodal Engineering Page 23

27 kwh 1000 Base Case ECM1,2 and JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Chart 16: Base Case and ECM1&2 Electricity Litres Base Case ECM1,2 and Chart 17: Base Case and ECM1&2 Propane As can be seen from Chart 17, improving envelope and window performance and reducing infiltration results in a 62% reduction in annual propane consumption. Enermodal Engineering Page 24

28 GREENHOUSE GAS EMISSIONS REDUCTION: The above ECMs will reduce greenhouse gas (GHG) emissions. Table 19 lists the GHG emissions factors used in the following GHG analysis, while Table 20 lists the GHG reductions associated with each ECM. Table 19: GHG Emissions Factors Electricity Propane 222g CO 2 eq/kwh 1602g CO 2 eq/litre Table 20: GHG Emissions Source GHG Emissions (tonnes CO 2 eq/year) Base Case ECM1 ECM2 ECM3 ECM1&2 ECM 1&2&3 Electricity Propane Total ECM1 insulation ECM2 windows ECM3 air seal The potential GHG reductions are: 1.45 tonnes CO 2 eq/year increased envelope performance 0.73 tonnes CO 2 eq/year increased window performance 2.99 tonnes CO 2 eq/year reduced air infiltration 2.18 tonnes CO 2 eq/year increased envelope performance and increased window performance 5.15 tonnes CO 2 eq/year increased envelope and window performance and reduced air infiltration Enermodal Engineering Page 25

29 RECOMMENDED ENERGY CONSERVATION MEASURES Air Sealing Uncontrolled air leakage accounts for 47% of the building heating, or about 2700 L propane/ yr, worth about $2000 at $0.75/L. This cost will rise. An air sealing contractor should be hired to seal the Hall ceiling, 3 rd Flr stairway and meeting room, various doors. Doors Front door, kitchen side door, back door (poor or missing weatherstrip and bottom sweeps. Big gap at bottom of kitchen door.) Hall ceiling (no air barrier, no seal on access hatch, multiple penetrations at light fixtures) Hall storage verandah (drafts at double doors, no weather seals) 3 rd Flr mtg room & closet and closet beside stair (open to roof, no air barrier. The existing insulation is not an air barrier.) One method to seal the ceiling would be to remove the existing loose fill insulation and apply a thin (3 6 cm) layer of spray polyurethane foam on top of the wood ceiling. This has some insulating value as well as acting as an air barrier. The ceiling at the sloped sections would have to be removed and ventilation channels installed in each rafter space between the soffit and the attic. The underside of the roof could then be sealed and insulated with spray polyurethane foam to achieve a continuous air barrier from wall to ceiling. The wood ceiling would then be re installed. This work should be coordinated with any roof modifications, eg. new ventilation chimney. Products: medium density spray polyurethane foam (SPF), Heat Loc Soya Spray insulation contractors: WayMar, Elora; Strassburger, Kitchener. Air sealing contractor: Canam Air Leakage Control, Toronto Roof and Ceiling Insulation Once the ceiling above the main hall is air sealed, then re insulate the attic above with additional blowin fibre insulation. However, as long as the existing wooden ceiling remains as leaky as it is now, adding fibrous insulation would be ineffective, other than as an air filter. As an alternative to the above, it would be better to abandon the attic ceiling insulation and insulate the entire underside of the roof with spray polyurethane foam (SPF) insulation. The insulation should be continuous from the top of the walls to the peak of the roof, changing the roof to a cathedral roof insulation design. No attic ventilation would be required nor provided. Again, the wood ceiling on the sloping sections would have to be removed for access to the roof and to seal the top of the walls to the underside of the roof. Adding 6 of SPF between the rafters would provide about R30 insulation. Enermodal Engineering Page 26

30 If a new metal roof is to be installed, then after the asphalt shingles are removed, 1 rigid insulating could be applied to the exterior of the wood sheathing, strapped with 1 x 4 wood, then the metal roof applied. The rigid insulation would add about R5 and provide a thermal break above the rafters. Roof material should be light in colour or galvanized to keep the roof cool in summer. A building envelope specialist should be consulted to carefully detail and specify this work. It should also be coordinated with any roof modifications, eg. adding a ventilation chimney. Wall Insulation The solid brick and masonry walls have no insulation and account for about 15 % of the annual heating energy or 850 L propane, worth about $640/ year at current propane price. This will increase. It is preferable to insulate the exterior of such walls rather than the interior. Insulating the interior of existing walls requires replacement of all interior finishes, and leaves significant thermal bridges at floors and interior walls where it is difficult to install a continuous layer of insulation. Insulation installed on the exterior can be continuous across interior walls and floors and can include an air barrier. It also moves the existing brick and masonry to the interior of the insulation where it adds beneficial thermal mass to improve comfort and reduce cooling and heating loads when outside temperatures fluctuate. A high mass building is much slower to heat up in the summer and requires less cooling capacity. Adding 50 mm (2 ) of rigid insulation (R10 R14) would reduce the annual heating energy by about $500. The insulation could be finished with stucco, brick or prefinished siding. The most common exterior insulation finish system (EIFS) consists of rigid polystyrene insulation and acrylic stucco. If we wish to preserve the appearance of the existing building, a new brick exterior could be installed using steel angle brink ledge fastened to the existing foundation and brick ties up the wall, but would add another 100 mm (4 ) to the wall thickness and would require some architectural treatment at the roof to maintain the same soffit profile. Windows would also have to be trimmed out. EIFS Systems Product: Sto Dryvit Replacement Windows The windows in the hall and downstairs were replaced about 20 years ago and are reasonably airtight. Replacing them with new low e argon units with insulating spacers would reduce heating energy about $250, but is hard to justify at a cost of about $1000 per window. The windows in the washrooms and 3 rd Flr meeting room however are very leaky double hung wood units from the original construction in about 1950 and should be replaced. Water Heater The electric water heater is already well insulated with additional glass fibre blanket and uses about 2.6 kwh/day, presently worth $140/yr at $0.15/kWh. The next improvement should be to insulate all Enermodal Engineering Page 27

31 accessible hot water piping. This can be done by Club members for under $50. for insulation material. A solar water heater would be hard to justify economically at cost of $4000. Heating and Air Conditioning Equipment The 2 propane furnaces are high efficiency condensing type with nominal 90% efficiency. Furnace #1 leads, furnace #2 follows. At the next service, the actual combustion efficiency should be measured to check that they are operating as well as possible. If they are, there is little energy saving potential in replacing them with newer furnaces at 94% rated efficiency. The first investments should focus on improving airflow and reducing heat losses. For example, furnace #1 has a serious restriction in return airflow. System improvements include: Improve the distribution of warm air Not enough warm air is reaching places where it is needed (eg. your feet, in the Community Room), and too much is going places it shouldn t. Community Room warm ceiling/ cold floor: 2 ceiling diffusers, wrong type, wrong location. Warm air doesn t reach the floor. Bsmt Hall dead grille: no air supplied from grille low on the wall. No other grilles or register here. Cold drafts from front door can attack ankles in Community Room and Kitchen without challenge. Kitchen Pantry warm fridge and freezer: This room has an uncontrolled supply air grille, keeping the fridge, freezer, pots and pans warm. Who wants to keep the freezer warm? Kitchen warm ceiling/ cold floor: 2 ceiling diffusers, wrong type. Do your feet ever get cold in here? Hall damaged floor registers, uneven airflow. Lightweight residential style not appropriate for a fine rental hall. Registers closest to furnace give lots of air; those farthest away, very little. Less significant than other problems, but still worth replacing registers with heavy duty registers with integral balancing dampers. Duct joints are not sealed. A lot of heated air leaks into the furnace room (to be recycled back to the return) and into floor joist spaces above the bsmt ceiling. Wasted, and steals air from the spaces that need it. Improve the design of return air ducting The return air duct for Furnace 1 is too small ( only 14 x 4 for cfm) and should be reworked. This restriction in airflow could cause the furnace to overheat and trip on high limit. It will certainly reduce the heating effectiveness and efficiency. Only one return grille for Furnace 1 was found in whole bldg in the floor in front of stage in Hall. More return grilles should be installed, and the system should either be separately zoned or combined; at present, the returns serve separate spaces, but the supplies are combined. Furnace 2 appears to return only from the bsmt storage room, through 2 holes cut in top of return trunk duct. Sheet metal joist liners nearby do not connect to the duct, don t go anywhere and are useless. Trunk runs above kitchen ceiling to go where??? Enermodal Engineering Page 28

32 Consequently, furnaces are drawing a lot of return air from the furnace room and the adjacent bsmt storage room. Since the furnace room is poorly sealed to the outdoors, the furnaces draw in a lot of outside air, heat it, then the leaky building lets it escape through the roof, etc. This gives a very well ventilated building, but at a very high energy cost, especially since it is usually empty with no one to enjoy the high ventilation rate. Return air is supposed to come from the occupied rooms. Furthermore, these basement rooms are dirty and are used to store cleaning products; the furnaces pump that air through the rest of the bldg. Recommendations: 1. Seal all sheet metal joints in supply and return ducts. with water based duct sealant. Seal all connections at furnaces. 2. Install balancing dampers at all accessible branch ducts. 3. Community Room: Either just replace existing diffusers with double deflection or nozzle type diffusers, or relocate them to low on the corridor wall, with double deflection grilles. 4. Close off supply air grille in kitchen pantry. 5. Check if bsmt hall register is connected to anything. (Maybe by restricting other outlets temporarily.) If it is, rebalancing airflows may revive it. Otherwise, add new supply register or two for the bsmt hall. 6. Kitchen: Replace existing ceiling diffusers with double deflection grilles. 7. Hall: Consider replacing all floor registers with linear bar grilles with balancing dampers (partly for better appearance & durability, partly for better air balance and airflow pattern) 8. Close duct and diffuser to bsmt storage rm. 9. Investigate where return ducts go, and it there are other return grilles, possibly covered. Is there a return grill in senior s room? 10. Provide new return grille in bsmt hall, either in wall with furnace room or ceiling outside of storage room. 11. Seal 2 holes in top of return trunk duct in bsmt storage room. Remove redundant joist liner. 12. Consider connecting both return trunk ducts together in furnace room. Improve the controls The building has at least 2 or 3 different areas by function Hall, Bsmt Community Rm, Seniors Rm and 2 furnaces, but only one thermostat, which is located in the basement hall. This is a simple arrangement but inefficient, and certain to dissatisfy some of the users. The system is not zoned if heat is required only in the Seniors Room, for example, the whole building has to be heated. When the Hall is the principle use, the thermostat does not respond to changes in load, eg. when there are 100 people dancing and warming up the room but the thermostat doesn t know and still calls for the furnaces to work. Or when the exterior doors are open and cool air enters the hall, it fools the thermostat to heat the whole hall. Furnaces are connected with a common supply air plenum but have separate return ducts and venting. The system should either be separately zoned or combined, not both. Enermodal Engineering Page 29

33 Recommendations 1. Investigate if there is a simple 2 stage thermostat that could control the 2 furnaces in sequence ( and air conditioners). Ie. first one turns on, then, if still needed, the second. If so, add a backdraft damper at the return air connections at each furnace beside air filter so that one furnace can run at a time. Since supply duct is shared, a single furnace will still supply air to all outlets, just less. 2. Investigate if zone dampers and thermostats for some zones, eg. seniors rm, are feasible. In the simplest scenario, they would be a sub zone or slave to the master thermostat. 3. It is probably not feasible to separate the ground floor from the upper floor and allocate one furnace to each, with separate thermostats. At present, spaces in the two floors share a common supply air trunk duct. They could be separated, but this would require more sheet metal and drywall ceiling work. Should be investigated 4. Investigate feasibility of converting to wood pellets at least for one of the two furnaces, if the supply of pellets becomes reliable, and there is a commitment to provide the regular maintenance required handling fuel, ash disposal, cleaning grate, etc. See Appendix D for comparative heating costs. 5. Investigate the feasibility of converting to heat pumps for both heating and cooling. See Appendix D. Electricity We did not specifically look at electrical equipment, but did notice the following: 1. Some fixtures still use incandescent bulbs. Eg. front entrance canopy, stage floods, Trustees Room. Incandescent bulbs that are used for more than a few hours per month should be changed to compact fluorescent bulbs. 2. Have exit lights all been changed to LED type fixtures or to compact fluorescent? 3. Whenever major appliances need replacement, buy EnergyStar labeled appliances. Choose appliance with lowest kwh/year rating. 4. Labels: Put better labels on controls and instructions where to find them if it is not obvious, eg. Hall ceiling fans. How DO you turn them off? They do not save heating energy when the bldg is unoccupied (the thermostat is in the bsmt and doesn t know what the fans are doing) and therefore should be turned off. Enermodal Engineering Ltd. Richard Lay, M.A.Sc., P.Eng. Christianne Aussant, M.A.Sc. Enermodal Engineering Page 30

Practical and Effective Approaches to Residential Ventilation for Production Builders

Practical and Effective Approaches to Residential Ventilation for Production Builders by Armin Rudd USDOE Building America Program for Affordable Comfort Conference 2002 Cincinnati, Ohio 18 April 2002