We are here to help you solve your problems.

AFUE - Annual Fuel Utilization Efficiency

Measures the amount of fuel converted to space heat in proportion to the amount of fuel entering the furnace. This is commonly expressed as a percentage. A furnace with an AFUE of 90 could be said to be 90% efficient. AFUE includes any input energy required by the pilot light but does not include any electrical energy for fans or pumps.

Air Barrier

Any material that restricts air flow. In wall assemblies, the exterior air barrier is often a combination of sheathing and either building paper, house wrap or board insulation. The interior air barrier is typically gypsum board.

Batt Insulation

Insulation that is typically manufactured out of fiberglass into ‘blankets’ sized for typical framing bays and manually fitted into place. They require extra diligence to ensure no gaps, voids, compression or misalignment where framing bays are not typical framing dimensions or include wiring and piping.

Blower Door Test

Diagnostic tool designed to measure the airtightness of buildings and to help locate air leakage sites. The airtightness of a building is useful knowledge when trying to increase energy conservation or decrease indoor air pollution, or control building pressures.

Blown-in Insulation

Insulation typically made from fiberglass or cellulose that is blown into construction assemblies dry or wet that inherently fills the entire framed assembly without any gaps, voids, compression or misalignment. Typically found in attics.

Building Envelope

The outer shell, or the elements of a building, such as walls, floors, and ceilings, that enclose conditioned space.


Insulation installation condition where the full thickness is reduced, resulting in increased density and reduced air pockets that drive thermal resistance. This undermines the effective R-value of the insulation.

Construction Documents

The drawings (plans) and written specifications that describe construction requirements for a building.

Convective Air Flow

As used with thermal bypass, this refers to air-flow that occurs in gaps between insulation and the air barrier due to temperature differences in and across the gap resulting in a stack effect or driving forces from more to less heat.

Direct Vent

A sealed ventilation system for combustion appliances that draws combustion air from outside the structure and vents combustion exhaust outside the structure. These systems may be combined with power vent exhausts. See Power Vent and Sealed Combustion.

Duct Blaster Test

Diagnostic tool designed to measure the airtightness of ductwork and to help locate air leakage sites. Duct leakage can increase heating and cooling costs over 30% and contribute to comfort, health and safety problems.

EF (Energy Factor)

A standardized measurement of the annual energy efficiency of water heating systems. It is the annual hot water energy delivered to a standard hot water load divided by the total annual purchased hot water energy input in consistent units. The resultant EF value is a percentage. EF is determined by a standardized U.S. Department of Energy (DOE) procedure.

Energy (use)

The quantity of onsite electricity, gas or other fuel required by the building equipment to satisfy the building heating, cooling, hot water, or other loads or any other service requirements (lighting, refrigeration, cooking, etc.)

Energy Assessment

A site inventory and descriptive record of features impacting the energy use in a building. This includes, but is not limited to: all building component descriptions (locations, areas, orientations, construction attributes and energy transfer characteristics); all energy using equipment and appliance descriptions (use, make, model, capacity, efficiency and fuel type) and all energy features.


A home, certified by the U.S. Environmental Protection Agency (EPA), that is at least 30% more energy efficient than the minimum national standard for home energy efficiency as specified by the 1992 MEC, or as defined for specific states or regions. ENERGY STAR is a registered trademark of the EPA.

Find out how much you can save on your project?