You should always install a vapor barrier to protect exposed ceiling insulation even if it's temporary. Consult with a building or safety expert to confirm where else in the structure a vapor barrier may be required.
In summary, according to the Ontario Building Code inside a residential building envelope all foam insulation products should be covered with an approved thermal barrier.
NOTE: FOAMULAR® Boards in a conditioned space must be covered by a 15-minute thermal barrier, such as gypsum board.
foam board can serve the function of housewrap if it's staggered and the seams are taped properly, and batt insulation can go into interior wall cavities with no vapor barrier if the exterior insulation is done well. It can sit in sunlight for a few weeks if absolutely necessary.
While there are no UV rays to destroy the foam board's insulative properties, interior exposure can create a fire hazard. Therefore, to qualify a building for an occupancy permit, most jurisdictions in North America demand that a thermal barrier, like drywall, cover the foam board.
DuPont™ Tyvek® weather barriers can be used either over or under sheathing.
Unlike other insulation materials, ECOCELL does not have to be covered with gypsum board. Leaving ECOCELL exposed is another reason ECOCELL is the cost effective solution for insulating basements and crawlspaces.
In general, if the foam rigid insulation is installed correctly and sealed properly, a vapour barrier may not be necessary. However, there are certain situations where a vapour barrier is recommended, such as in areas with high humidity levels or where there is a risk of moisture infiltration.
Insulation boards tend to have good moisture resistant and water repellent qualities. Products such as Celotex and EcoTherm boards for instance have aluminium foil facings on both sides, and a PIR foam that is resistant to water.
Spray Foam Cannot Be Exposed Without A Protective Coating.
When it comes to the elements of nature, spray foam must be protected with a coating. Sun, rain, snow, or sleet can all cause damage to spray foam insulation.
Insulation Foam Boards Don't Work On Uneven Walls
This allows moisture to seep in. Excess moisture can cause mold, mildew, odors, decay, fungus growth and wood rot.
A: Myron Ferguson, a drywall contractor in Galway, N.Y., responds: These days, rigid foam is usually installed on the exterior, but back in the '80s I installed a lot of drywall directly over interior foam board — typically 1-inch foil-faced polyisocyanurate fastened right to the framing.
Yes, covering your insulation with a vapor barrier plastic before installing drywall is crucial. It prevents moisture buildup that can lead to mold, rot, and even structural damage. A polyethylene vapor barrier also adds a layer of fire protection, making your home safer.
Foil is a low emissivity material
For a clear unventilated cavity, adding a low emissivity foil facing to at least one side of the cavity will improve, maybe even triple the thermal resistance. This means that adding a foil facing to insulation can significantly improve the U-value of the construction.
Don't worry about that one. But with that strong air stream, breaking up of fiberglass strands and moving them around is a cause for concern. So, buy Tyvek, and use it to cover the insulation; staple it to framework. It is not a vapor barrier, so it is OK to put over the insulation.
If looking to install insulation boards within joists, you will need to first create an air gap. This is to allow ventilation and air movement.
When installing insulated plasterboard using the mechanical method, such as with screws, it is recommended but not necessary to use a vapour control layer. The best example of this is insulation in the loft.
DuPont Thermax™ is a higher efficiency insulation that performs well in interior spaces. Since it doesn't require a thermal barrier you can achieve a high R value without covering it and increasing wall thickness.
Walking on them could damage the boards, reducing their effectiveness and potentially affecting their structural integrity.
Rigid polyurethane and polyisocyanurate foams will, when ignited, burn rapidly and produce intense heat, dense smoke and gases which are irritating, flammable and/or toxic. As with other organic materials the most significant gas is usually carbon monoxide.
if it is hot outside, the reflective part of your foil insulation must face outside. if it is freezing outside, the best orientation of the reflective part is inside.
Yes, House Wrap Does Come First!
Often, those installing foam insulation ask, “Do I put house wrap on first or second?” Whether you're installing James Hardie siding or not, house wrap is always applied first. The experts place the material in the proper orientation to achieve maximum insulation.
Now there is an alternative. IMPAK's TeknaPore™ offers the same lightweight durability, air permeability, and water resistance capabilities as Tyvek®, but with a company that offers outstanding customer service, flexible print order quantities, and low MOQs for medical and sterilizable pouches.
For example, House wrap by itself is not an air barrier, it is a vapor barrier. However, IF installed properly, which is rare, with taped seams, bottom, top edges, and no tears, it acts as an air barrier. So primarily it acts as a vapor barrier, but installed properly can do both; vapor barrier and air barrier.