Energy Tour of Old Schoolhouse Common
March 18, 2008
Andy Perchlik
Rich Phillips
Ernie Penley
1) Insulation Deficiencies:
a) The wood walls are all 4 inch filled with cellulose type insulation, which has settled at least a small amount (1’). The R-value of this wall is no more than 14 even given the fact that the inside was strapped and 5/8” sheet was added on the interior. The current day recommendation is R 40. Increasing this R would be expensive whether inside or outside is chosen. Outside would necessitate all new siding.
b) The attic has about 10 inches of pour-in cellulose type insulation for an R of about 32. This compares with current-day recommendations of R 70. The attic is wide open and much more pour-in insulation could be added.
c) There are considerable exposed and below-ground exterior concrete walls with no insulation on either face. These walls have a very low R-value. In fact, they mostly radiate the heat energy they absorb from the building’s heating system to the outside. That effect is clearly seen outside the below-ground walls where the snow is melted well back from the wall. This is a gross heat loss. Unfortunately, the corrective action involves either 1) digging up all along the outside of the foundation to insulate and extending insulation from the footing to the top of the wall (including the above-ground wall), 2) insulation the entire wall in the inside. These corrective actions will be expensive. The outside option allows for mastic application on the concrete wall, which may help where leakage has been a problem. If either option is pursued the north sidewalls should be the first tackled. The sun definitely helps the heating issue on the south side.
d) It is clear we have some level of problem as we are using about 53,000 BTUs per square foot per year when a tight, well-insulated home uses about 40,000 BTUs per square foot per year.
2) Lighting
The lighting in the rooms is fluorescent (T-12). These are more energy efficient fluorescent lamps (T- 8), but their use requires updated fixtures, which may not make economic sense. We will look at the comparison for the lights in the Town Clerk’s Office and the Library, which are in use the most. The lower hall lighting is compact fluorescent and Ernie has changed most of the upper hall lights to compact fluorescent as the incandescents fail.
3) Domestic Hot Water
The current system is based on an electric water heater, which appears appropriately sized, as it can’t keep up with extraordinary demand. The piping system to the service points is quite short and compact. There is not a lot of hot water wasted by people waiting for the hot water wasted to displace cold water in the pipes when service is called for. The only option to look into here is incorporating an additional tank and circulator pump to use boiler water to heat the domestic hot water during periods when the boiler is operating. The option of solar heating of domestic water with electrical backup could also be explored.
4) Heating System
The heating system includes two Weil Mclain boilers rated at _______BTU/hr net, a one horsepower circulator pump running continuously and zone values operated by thermostats in each room. The boilers are controlled to come on together and if one boiler is out some of the building is cooler than set on the thermostats. This is probably the area that is furthest from the boiler where system water temperatures have reduced too low for adequate heat transfer.
We will look into the conversion to a wood pellet system, but we need to take the steps to reduce the loss of energy in the building before implementing a conversion, if we indeed decide to convert.
5) Electrical Power
We have the record of monthly energy use since 2003 (attached). The power use averages about 2500 kwhrs/month but peaks in the winter to near 3500/month. The average is about 3.5X the use in a single home. The reason for this is not obvious and will be studied. There are 5 refrigerators and 4 freezers operating continuously in the building. This amounts to about 720 kwhrs/month (nearly a third of the total average demand). The one horsepower circulatory pump running continuous during the heating season uses about 540 kwhrs/month. Together, these units represent about half the average demand in the winter. We will look into the possibility of controlling the pump so it only runs when heat is called for somewhere ion the building.
6) Quick Fixes
We found that a shut metal door under the turbine blocked one of the turbine ventilator entrances. Ernie will look into this. Two of the air inlet structures in the gym are not used. These need to be better sealed better since they are serving no purpose at this time.
7) Windows
The windows are all double pane and further investments do not seem warranted. About five windows are a little less quality than the Anderson windows more recently installed but they are double pane and satisfactory
8) Boiler Room Heat
The boiler room was at about 90 degrees. We discussed exhausting some of that heat into the building. But we decided that most of this heat was already finding its way into the adjacent and above rooms evidenced by the higher temperatures in these rooms. Some of the heat was being lost however, to the uninsulated concrete outside wall as discussed above.
We will now focus on making the necessary evaluations of cost, payback and phasing of suggested improvements