Buildings

1. Air Tightness

• 1.1. There shall be a continuous, durable air barrier enclosing the conditioned space. This includes features such as chases, knee walls, soffits, garage interfaces, intersecting walls, tubs and showers and dropped ceilings.
• 1.2. Tightness shall be less than or equal to .30 CFM50 per square foot of conditioned envelope area. Among other areas, this will require attention to air sealing the sub-floor to bottom plate; holes under tubs; window and door rough openings; attic hatches and electrical, plumbing and mechanical penetrations.

2. Ventilation and Moisture Management

• 2.1. There must be a filtered whole-house mechanical fresh air ventilation system in compliance with ASHRAE 62.2.
• 2.2. All bathrooms shall have a fan vented to the outside capable of exhausting: 20 CFM continuously; or 50 CFM intermittent (requires a minimum fan rating of 70 CFM)
• 2.3. All kitchens shall have a fan vented to the outside capable of exhausting 100 CFM. (requires a minimum fan rating of 120 CFM)
• 2.4. All ventilation ducts in unconditioned spaces, excluding kitchen exhaust ducts, shall be insulated.
• 2.5. All ventilation ducts shall terminate at or beyond the exterior skin of the building.
• 2.6. Crawlspace floors shall have 100% coverage with vapor retarder.

3. Insulation and Windows

• 3.1. Insulation shall be installed to manufacturer s specifications, with no substantial gaps, voids, compression or wind intrusion.
• 3.2. Insulation and the air barrier shall be installed in physical contact with each other.
• 3.3. Attic insulation shall equal R-38 or greater excluding vaulted ceilings which shall be insulated to code.
• 3.4. Raised heel trusses, or equivalent, shall be used to ensure full insulation value over the top plate of the exterior wall.
• 3.5. Windows and glass doors shall have an overall solar heat gain co-efficient (SHGC) of .38 or less.
• 3.6. Windows and glass doors shall have an overall U-value of .35 or less.
• 3.7. Slabs shall be insulated to code.

4. HVAC Sizing and Installation

• 4.1. Heat pumps shall have a minimum SEER rating of 14 and a minimum HSPF of 8.2.
• 4.2. Heat pumps shall have an outdoor thermostat installed to prevent supplementary heater operation when the heat pump is capable of meeting the load.
• 4.3. Furnaces shall be 90% efficient and their cooling systems shall have a minimum SEER rating of 13.
• 4.4. All duct connections shall be sealed with a UL listed bucket mastic product.
• 4.5. Duct leakage, measured in cubic feet per minute at 25 pascals, shall not exceed 3% of the conditioned square footage.
• 4.6. Mechanical systems shall be sized to within ½ ton of the ACCA Manual J. ACCA Manual J room-by-room load calculations, including all inputs, shall be submitted for each plan to verify sizing.
• 4.7. The measured airflow for each room shall be within +\- 10% of the ACCA Manual J calculation.
• 4.8. Refrigerant charge shall be installed per manufacturer s specifications.
• 4.9. Inert gas (nitrogen) shall be used during any brazing/soldering of refrigerant lines.
• 4.10. Indoor and outdoor system components shall be matched according to the Air Conditioning and Refrigeration Institute (ARI) directory.

5. Pressure Balancing

• 5.1. All rooms within the conditioned space except baths and laundry shall not exceed +/- 3 pascals pressure differential with respect to the outside when interior doors are closed and the air handler is operating. Returns, transfer grilles or jump ducts shall be used to balance each room in addition to door undercuts.

6. Energy Star and Appliances

• 6.1. Home shall meet Energy Star® Home requirements.
• 6.2. Home shall have an Energy Star® labeled refrigerator.
• 6.3. Home shall have a minimum of two light fixtures outfitted with fluorescent lamps. Either T-8 tubular, circular fluorescents or compact fluorescents are acceptable.
• 6.4. Electric water heaters shall have an energy factor (EF) of at least .93.
• 6.5. Gas water heaters shall have an energy factor (EF) of at least .61.
• 6.6. Recessed lights, if used, shall be air tight and insulation contact (IC) rated.

7. Combustion Safety

• 7.1. Any combustion appliance inside the conditioned space, other than gas ranges and wood fireplaces, must be direct vent or power vented. Vent free gas logs are not allowed.
• 7.2. One hard-wired carbon monoxide (CO) detector shall be installed per 1,000 sq. feet of living space in homes which have any combustion appliance within the conditioned space or which have an attached garage. (minimum 1 per floor)