Unvented Roof Green Building

Most advocates of unvented roofs are focused on saving time and money rather than long term durability.

Unvented roof green building.

By martin holladay august 21 2015. Q a spotlight sanity check on an unvented roof assembly an insulation contractor has suggested a way to save money but the homeowner worries about the added risks of moisture accumulation. The complete source for building designing and remodeling green homes. A properly vented roof.

The plan is to spray open cell foam under the roof deck. There will be ducting and other hvac equipment in the attic. 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. While unvented attics are gaining acceptance homeowners must realize their limitations including.

No insulation installed yet. This document provides a brief description of different types of unvented roof assemblies and the benefits of unvented roof construction. Roofs are like walls that are severely out of plumb and an unvented wall can work. These assemblies are created by eliminating ventilation openings and moving the thermal moisture and air control boundaries to the plane of the roof deck.

Become a gba prime member and get instant access to the latest developments in green building research and reports from the field. When constructing unvented roofs with asphalt shingles in hot humid climates a vapor barrier must be installed between the asphalt shingles and the roof deck. Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction. Owens corning is promoting an insulation method that has long been considered risky.

Many local building codes do not account for non standard construction alternatives such as unvented attic assemblies. Musings of an energy nerd can unvented roof assemblies be insulated with fiberglass. The complete source for building designing and remodeling green homes. Green building blog podcast.

Ib pvc roofing 1 2 roof osb sheathing above 5 8 gyp. How to insulate an unvented roof. Vented vs unvented roof in 1960 cape cod. Also unvented roof assembles make complicated roof geometries more viable as they are difficult to ventilate effectively.

In the process of construction. Bd ceilin unvented flat roof greenbuildingtalk greenbuildingtalk green building forums on insulating concrete forms icf structural insulated panels sip radiant heating geothermal heat pumps solar power green construction projects green building forums general forum. The complete source for building designing and remodeling green homes. However as the future owner i m beginning maybe a bit too.

Is it a good idea to make an unvented roof with a lot of foam on the outside. Currently have a standing seam metal room installed over synthetic felt over osb.