One of the most often missed or not well executed details is the connection between the wall air barrier and roof assembly.
Pitched roof vapour barrier.
Flat roof vapour barrier materials when constructing a flat roof there are two types of materials commonly used.
If the roof covering or roof membrane is a material of high moisture resistance or impermeable then the building regulations require a 50mm wide ventilation gap beneath the roofing felt and tiles.
Next to that you may also buy a moisture regulating vapour barrier membrane that can manage the damp even better.
A flat roof vapour barrier such as iko s mvp modified vapour protector offers appropriate moisture protection.
Including flat roof vapour barrier for extra secure roofing solutions.
If the roof is insulated with foil faced insulation blankets the aluminium side can serve as a vapour barrier at the same time.
This removes the need for ventilation in the insulation a benefit that is particularly important with cold pitched roof construction.
However note that one should seal the seams here as well.
Bituminous vapour retarders asphalt mixed with felt or fiberglass or non bituminous vapour retarders plastic laminate or aluminum coated.
The ventilation requirements of a pitched roof depends on the type of roof membrane used under the tiles or slates and battens to keep moisture or rainwater coming in from outside.
You ll find pitched roofing products here.
Where high water vapour resistant type hr underlay e g.
They permit water vapour in the roof space to permeate through to the batten space where the natural movement of air through the.
The roof is covered with high water vapour resistant type hr underlay and the pitch exceeds 35 or the span exceeds 10m this is in addition to eaves ventilation.
Tyvek membranes are specially designed to minimise interstitial condensation and remove the need for ventilation in the insulation providing a holistic solution to energy efficient warm pitched roof constructions.
With all the insulation board in place start at the top of the roof and fix the vapour barrier to the rafters using a staple gun fold the barrier material into a sort of z at each rafter so that the staple goes through a double thickness.
Looking for pitched roof materials.
I have recently finished installing a celotex warm roof to my house i have several sheets left over my flat roof extension needs to be recovered and insulated also as a warm roof can i use the 100 mm ga 4000 insulation boards i have left over for this project if so would i need to use a vapour control barrier or would taping the joints act as a vapour barrier the roof surface will be.
Issue of connecting the wall air barrier assembly to other building assemblies such as below grade window systems and roofs need to be completely understood in order to design and construct a functioning building enclosure.
Reduce heat loss and boost energy efficiency with market leading vapour control layers vapour barrier membrane and vapour control barriers.