Underlayment (commonly referred to as sarking in Australia) is a vapour barrier that is laid between the roof deck and the CertainTeed shingle roofing shingles. American Shingles uses and recommends CertainTeed’s Winterguard 'Peel & Stick' self adhering range of waterproofing underlayments.
Winterguard protects the roof deck during the shingle roofing application as well as providing secondary protection during the life of the roof shingles on the building. It also assists in keeping the critical path of the building project on track as other trades can continue working during inclement weather even though shingles haven’t been fully applied. Once laid, the Winterguard underlayment effectively waterproofs the building.
Winterguard HT is a composite based material of asphalt and elastomeric polymers that is self adhesive and applied directly to the plywood roof deck. The flexibility of Winterguard provides a waterproof barrier that is not only sticky, but seals around the shanks of the nails driven through it.
In the event of a catastrophic damage to the shingles, Winterguard HT will stay adhered to the roof deck and assisting in keeping the water out.