Blocking Vented Roof With Rigid Insulation

Acfoam crossvent is a thermally efficient cross ventilated non structural composite roof insulation.

Blocking vented roof with rigid insulation.

The superattic system creates a continuous air and insulation barrier directly beneath the attic roof with no thermal bridging to compromise energy. For the same reason insulation shouldn t touch the roof s underside. Atlas offers accessories to promote airflow. Covering up the soffit vents with loose fill or batts which can happen if you stuff insulation along the eaves is a huge no no.

The details of how to do this in a moisture safe way prior to adding the above deck r varies with climate zone. However most cathedral ceilings and low slope flat roofs are insulated roof assemblies. 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. The attic roof vent baffles baffles hold the insulation away from the roof deck to permit air to enter the attic or under roof space.

The superattic system utilizes proprietary silverglo rigid foam insulation panels to fully seal and insulate the attic directly beneath the roof rafters and directly inside the gable ends. We use this same design under roofs that cover cathedral ceilings but on occasion find that more air space and air flow up under the roof sheathing are needed in those structures. The airflow from the soffits to the ridge vent keeps the roof cool and prevents ice dams and the material will block that flow. So much information has been devoted to the subject of roof venting that it s easy to become confused and to lose focus.

Venting at solid roof blocking dan. The majority of roofing experts agree that ridge vents are the most effective and cost effective roof vents available. A vented attic where insulation is placed on an air sealed attic floor is one of the most underappreciated building assemblies that we have in the history of building science. Techni flo engineered ventilation system features a unique design.

Insulated roof assemblies can be vented or unvented. Consisting of acfoam ii or acfoam iii polyiso insulation board and osb or cdx plywood separated with and bonded to 5 individual expanded polystyrene vent spacer strips. I have roof vents so i have roof ventilation. 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.

If you don t want to use sips or nailbase read this article tolearn the four basic approaches to insulating unvented roof assemblies. So i ll start by saying something that might sound controversial but really isn t. 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. A roof over a vented unconditioned attic does not need to include any insulation.

While hardly anybody agrees on the best roof ventilation system everybody agrees some roof vents do hardly any good at all.