Unvented Roof Insulation

If you don t want to use sips or nailbase there are four basic approaches.

Unvented roof insulation.

In the most recent issue of fine homebuilding martin holladay wrote a piece on insulating unvented roof assemblies. Unvented roof assemblies should be insulated either with air impermeable insulation rigid foam or spray polyurethane foam or with a combination of foam and air permeable insulation. Senior engineer manager at icynene john broniek makes the case for the unvented attic assembly and why insulating the underside of the roof makes sense. This piece originally the quest for greater energy efficiency in buildings has led to increasing interest and need for insulation improvements in hvac equipment more airtight construction new materials and assemblies.

Low slope and steep slope unvented roof systems i e. But in it unfortunately all four options provided are dominated by foam. Designs and houses with unvented roof insulation systems have also been developed and constructed in cold and mixed climates. Four options for building an unvented roof assembly.

Over the past five years several unvented roof insulation systems have been developed by the building science consortium for use primarily in hot dry and hot humid climate zones. Insulation and air barrier are applied directly to the underside of the roof deck are common in applications where designers are seeking cost effective and energy efficient roof assemblies.