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Construction Specifications

This specification guide has been put together to assure a quality energy efficient system that will perform properly and to the highest level of efficiency. The items listed below give the greatest energy savings and the best return for the money spent.

Note: It is important to remember that when building to these specifications, it is imperative that you receive professional help in correctly sizing the HVAC equipment to avoid over-sizing which can lead to high utility bills as well as moisture and mildew problems.

Slab Insulation:
R-8 minimum slab insulation is recommended.

Exterior & Common Wall Insulation Systems:
Insulating Concrete Forms, 5-1/2” ThermaSteel Panels, 6” Structurally Insulating Panels or 2” x6” Foam filled or Spray-on Cellulose stick framing.

Recessed Areas, Cantilevered Floor, Crawl Space Areas & Knee Wall Insulation Systems:
5-1/2” ThermaSteel Panels, 6” Structurally Insulating Panels or 2” x 6” Foam filled or Spray-on Cellulose Stick Framing.

Attic Insulation Systems:
7-1/2” ThermaSteel Panels, 8” Structurally Insulating Panels, R-45 Cellulose or R-45 Foam Insulation.

Windows:
Two pane, tinted and/or low-E glazing with a thermal break for aluminum windows. Two pane, tinted and/or low-E glazing for wood and vinyl windows.

Doors:
All exterior doors should be solid core wood/fiberglass or steel with poly-core foam inside. The use of sliding glass doors and double French doors are not recommended.  To obtain a French door or sliding glass door look, the use of atrium doors, where one side is fixed is recommended.

Air-Infiltration:
Caulking of ThermaSteel Panels, Insulating Concrete Forms or Structurally Insulated Panels, Header plates, base plates, penetrations into the attic, windows and doors. Caulking of Stick Framing:  Corners and “T’s”, header plates, base plates, multiple studs in the exterior walls, penetrations into the attic, windows and doors.

Special attention should be paid to pocket doors, because the method of installation used makes it more difficult to totally seal up the wall to the attic to eliminate air-infiltration. The use of pull down attic stair doors and scuttle holes should be kept out of the heated and cooled area. All attic pull downs and scuttle holes should be covered with polystyrene foam energy lid covers. The standard size for scuttle hole covers is 24” x 32” x 6” thick, and the standard size for Stairway Energy Lids is 22” x 54” or 25” x 54”. The use of these products will also help keep insulation from falling down when these units are opened.

Recessed Lighting:
All recessed can lights should be totally enclosed “air tight” insulated can lights (such as the Helo Model Number H7ICTNB with a 30 PAT or 30 WAT air tight trim ring).
Note: It is important to remember that one (1) regular recessed light represents one (1) square foot of un-insulated attic space with a hole in it (twenty recessed lights would represent a 3’0” x 6’8”
open door in your attic).
As little as a 4% void in the ceiling insulation results in an overall increase of 50% in the heat loss/heat gain in the attic.
All lights should be compact fluorescent bulbs (13 watt output for 75 watts of light; these lights are also rated at 10,000 hours of life vs. 750 hours of life for regular bulbs).

Attic Ventilation:
One (1) square foot of natural (soffitt, ridge and gable) ventilation required for every three-hundred (300) square feet of attic space.
We do not recommend power ventilators of any kind.
It is important to use polystyrene vent chutes or cardboard baffles around the perimeter walls to insure that installation is of the proper depth over the wall plates and so that insulation does not spill over into the soffitt vents. If ThermaSteel Panels or Structurally Insulated Panels are used for the roof of the structure, the
attic should not be ventilated at all. If this type of insulated roof system is used, there should be no gas pipes or gas appliances of any kind located in the attic.

Fireplaces:
Locate all fireplaces on inside walls when possible.
All fireplaces must be vented with outside air in order to draw properly! Glass doors are highly recommended.

Fans:
All bath and laundry room fans should be of the type that have a built-in humidistat that will automatically come on when the interior humidity reaches 50% (such as the Nutone QT 100 cfm LWM*). *This particular model has a motion detector to turn lights in the bathroom off and on-- another energy saving feature. All fans should be vented to the outside of the structure; the use of re-circulating vent--hoods is not recommended.

Duct Work Location:
All duct work should be located in conditioned space when ever possible.  In single story structures, this can be accomplished by installing the duct work in fur downs, crawl spaces, basements or underground.
For two story structures, the duct work can be installed between floors, fur downs, crawl spaces, basements and underground if necessary.  If the duct work has to be located in the attic, then lay the duct work on the rafters and cover them with foam or cellulose insulation.  For gas HVAC systems, it is important to have a return in every room so that the structure cannot be put into negative pressure when a door is closed. This will keep the structure from drawing air back down the gas flues and creating a dangerous situation.
Carbon Monoxide Detectors are required in every area where a gas flue and/or a gas appliance is located. See EnergyWise’s HVAC Specification Guide.

HVAC Equipment:
All HVAC system(s) must be A. R. I. matched system(s) with a SEER or EER rating of at least 12. All natural gas furnaces shall have an AFUE rating of 80t o 90%. Propane and resistance heat furnaces are not recommended.

The HVAC Air Purifying System
Every HVAC unit shall be equipped with a UV-Aire model UV-18X (or equivalent) to control airborne contaminants and mold build-up on the coils and condensate drains. Every HVAC unit shall be equipped with a Honeywell C7232 (or equivalent) carbon dioxide sensor and controller used to control the amount of fresh outdoor air supplied to maintain acceptable levels of CO2 in the space.

More Energy Saving Suggestions

Hot Water Heaters:
We recommend the use of High-Efficiency Foam Insulated Hot Water Heaters (such as the Rheem “Energy Miser” Series). All hot water heaters should meet or exceed the National Appliance Energy Conservation Act (NAECA) requirements. All hot water heaters should be located in conditioned space. The use of an R-11 Insulated Fiberglass Vinyl PVC Faced Blanket should be used on all heaters regardless of location (blankets must meet Federal Specification HH-1-55BB). Be sure to insulate under the heater before it is installed with R-5 polystyrene foam board. For electric heaters, be sure to insulate the top cap as well. Gas heaters must be vented, so the top of the water heater cannot be insulated. Hot water lines should be insulated with 1/2” thick PVC Closed Cell Insulation from the hot water heater to the point of use.

Tubs and Showers:
Locate all tubs and showers on the inside walls when possible. Insulate around and under all tubs and showers. For showers, the use of low water/high pressure 2 gallons per minute heads is required.

Toilets:
The use of low-water. 1.6 gpf elongated bowls are preferred. All bowls should conform to The Energy Policy Act of 1992 (EPACT).

Washers and Dryers:
Washers and Dryers such as the Maytag Neptune High-Efficiency Modes are recommended, because they use 60% less water and 2/3 less energy than the average washing machine, and they spin up to 90% of the water out of the laundry requiring as much as 50% less drying time.