Attic Insulation In Rafters Or Trusses

New rules and practical interpretation.

Attic insulation in rafters or trusses.

We prefer recycled insulation for obvious reasons. Encapsulating the rafter or top truss chord roof framing members with spray foam will improve the energy efficiency of the attic space. This is because the effects of thermal bridging are limited which also results in the elimination of melt lines on the roof surface in cold climates. This insulation strategy has not changed in recent code iterations and is not discussed in this article.

If you ve measured your attic space and feel you have enough room to accommodate living space chances are you have rafters or you have special trusses called attic trusses which create a large open space under the peak of the roof. Attics are fresh air ventilated so provisions must be made to reroute the attic s ventilation through the rafter spaces and the rafters must then be insulated. In unfinished space an attic insulation is typically laid between the joists. Although not expressly.

If you re considering turning your attic into conditioned storage or living space it s worth changing tactics to insulate between the rafters and wall joists instead of the floor. You can use rigid foam panels or do as tom silva does with nearly all houses these days. Safety precautions and mistakes to avoid during garage roof insulation. Polyurethane or polystyrene spray foams can provide thorough coverage to roof rafters and attic walls in much less time than is needed for other materials.

It is important to note when insulation is on the floor of the attic the space between the insulation and the roof deck must be vented to the exterior. Hire a pro to install spray foam insulation. The joists might then be covered with osb or plywood to form an attic floor for storage. Ibc section 1203 3 outlines the only circumstances when a roof may have an unvented attic or enclosed rafter truss assembly.

Insulation stops also known as attic baffles or rafter vents are designed to provide adequate air flow from the soffit vents to the gable or ridge vents in a home s attic. If you are planning to use wool then it is imperative you wear protective clothing goggles and a face mask since the wool is an irritant. The are similar to trusses in this regard. By contrast conventional trusses have supports called webbing that zigzag through the attic space.

Insulating below the rafters normally people use mineral wool or insulation boards to insulate the rafter space. This board forms the bottom member of each rafter and of course the ceiling of the space below. An attic conversion is a great way.