The International Residential Code (IRC) requires either a Class I or II vapor retarder on the interior side of frame walls in climate zones: 5, 6, 7, 8 and marine 4 (see climate zone map).
Do I need vapor barrier with roxul?
roxul Comfortbatt is an unfaced semi-rigid batt insulation and a vapor retarder may be required by building code depending on the geographic location of the building. The use of a vapor retarder will limit the amount of water vapor that will move to the outside wall reducing condensation in the wall assembly.
Is mineral wool a vapor retarder?
Some insulation materials, like mineral wool and fiberglass, are vapor permeable, while others, like XPS, EPS, polyisocyanurate and closed-cell spray foam, are relatively impermeable. Selection of a particular arrangement of material layers, and the vapor permeance of those layers, will control vapor diffusion.
Can you insulate without vapor barrier?
Not every type of insulation needs a vapor barrier. But if it does, the barrier should face inside in northern, heating climates, and outside in humid southern climates.
Do I really need a vapor barrier?
If you live in a mixed climate hot and humid with several heating months in the winter, you probably need a vapor retarder. Specifically, if you live in climate zones 4C (marine), 5, 6, 7 and 8.
What happens if you don't use vapor barrier?
If water vapor diffuses or infiltrates into the wall cavity and finds the cool surface, moisture problems can occur. Of course, you can have moisture problems here even without the exterior vapor barrier because of what Bill Rose calls the rule of material wetting.
Does spray foam insulation act as a vapor barrier?
Spray insulation foam itself acts as a vapor barrier. Vapor barriers were traditionally applied as an attempt to curb utility costs. The thought was that preventing water movement from outside the house to inside would reduce energy costs. Ultimately vapor barriers often caused more harm than good.
Do you need a Vapour barrier with rockwool?
Mineral wool typically doesn't require a vapor barrier. Its high-density level allows it to absorb moisture before it has a chance to penetrate the interior walls of the foundation.
Can you leave rockwool exposed?
Roxul is our #1 choice of insulation in exposed areas. It is non-flammable. After installation it releases very little dust comparatively. The dust released has really no harmful effects other than slight irritation.
Do you need a mask for rockwool insulation?
Cover open ventilation ducts to reduce particulate in the ducts. In confined spaces with poor ventilation use protective goggles and a dust mask. Wearing gloves and loose fitting, long-sleeved, long-legged work clothes is also advised.