Unvented Roof Insulation Mineral Wool

Yes unvented roof assemblies can be insulated with fiberglass a wufi post and not just in climate zones 2b amp.

Unvented roof insulation mineral wool.

If you choose or need to go with an unvented roof you would need either exterior insulation or a flash coat of closed cell spray foam first then you could round out the insulation package with mineral wool. This option gives builders an alternative to using spray foam insulation while providing the ability to use cost effective easy to install air permeable insulation systems. The semi rigid batts are more dense than traditional batts or rolls and are quick and easy to install. If you have an easy roof to vent and decide to go that route you could use mineral wool insulation between the rafters and beneath the vent channels.

Martin s post focuses on the marketing of owens corning 039 s propink unvented attic insulation system. Prior to the completion of research and publication of the 2018 irc concerns about condensation in warm humid climates prevented the practice. It also provides superior sound control. Mineral wool has an r value comparable to spray cellulose or high density fiberglass batts.

Rockwool multifix is a mineral fiberglass faced stone wool product that can be installed under many single ply membranes. Air permeable insulation such as fiberglass batts dense packed cellulose or blown in fiberglass can t be used alone for an unvented assembly since these types of insulation can allow moist indoor air to reach the cold roof sheathing leading to condensation or moisture accumulation. Thermafiber ultrabatt mineral wool is designed to provide thermafiber ultrabatt mineral wool is designed to provide excellent thermal insulation in residential and light commercial building. Building unvented attic assemblies using fiberglass and mineral wool.

Since it is made from non directional stone fibers the insulation is water repellent microbial growth resistant fire resistant and denser than other insulative materials. Building unvented attic assemblies with fiberglass and mineral wool. Like fiberglass mineral wool can be installed in batts. Single ply roof insulation.

The 2018 international residential code irc adds a new option for the use of fiberglass and mineral wool insulation in unvented roof assemblies in climate zones 1 2 and 3 following basic requirements outlined in the code. The 2018 international residential code irc allows air permeable fiberglass and mineral wool insulation in unvented attics in climate zones 1 2 and 3. Our new guide details how to do this.