Louver - A vented opening into the home that has a series of horizontal slats and arranged to permit ventilation but to exclude rain, snow, light, insects, or other living creatures.

Outrigger - An extension of a rafter beyond the wall line. Usually a smaller member nailed to a larger rafter to form a cornice or roof overhang.

Bedrock - A subsurface layer of earth that is suitable to support a structure.

Blocked (rafters) - Short "2 by 4's" used to keep rafters from twisting, and installed at the ends and at mid -span.

EER (energy efficiency ratio) - A measure of cooling efficiency computer by dividing a cooling unit's output in BTUs by its input in watts.

Incandescent lamp - A lamp employing an electrically charged metal filament that glows at white heat. A typical light bulb.

ú Septic permit - A health department authorization to build or modify a septic system.

Blankets - Fiber-glass or rock-wool insulation that comes in long rolls 15 or 23 inches wide.

Compressor - A mechanical device that pressurizes a gas in order to turn it into a liquid, thereby allowing heat to be removed or added. A compressor is the main component of conventional heat pumps and air conditioners. In an air conditioning system, the compressor normally sits outside and has a large fan (to remove heat).

Damper - A valve inside a duct or flue that can be used to slow or stop the flow of air or smoke.

Fire stop - A solid, tight closure of a concealed space, placed to prevent the spread of fire and smoke through such a space. In a frame wall, this will usually consist of 2 by 4 cross blocking between studs. Work performed to slow the spread of fire and smoke in the walls and ceiling (behind the drywall). Includes stuffing wire holes in the top and bottom plates with insulation, and installing blocks of wood between the wall studs at the drop soffit line. This is integral to passing a Rough Frame inspection. See also 'Fire block'.

Floating wall - A non -bearing wall built on a concrete floor. It is constructed so that the bottom two horizontal plates can compress or pull apart if the concrete floor moves up or down. Normally built on basements and garage slabs.

Lap - To cover the surface of one shingle or roll with another.

Mushroom - The unacceptable occurrence when the top of a caisson concrete pier spreads out and hardens to become wider than the foundation wall thickness.

Pump mix - Special concrete that will be used in a concrete pump. Generally, the mix has smaller rock aggregate than regular mix.

Square - A unit of measure -100 square feet -usually applied to roofing and siding material. Also, a situation that exists when two elements are at right angles to each other. Also a tool for checking this.

Stop Order - A formal, written notification to a contractor to discontinue some or all work on a project for reasons such as safety violations, defective materials or workmanship, or cancellation of the contract.

Ton - A measure of cooling power. One ton equals 12,000 BTU's.