Garage Builders Nashville
March 17, 2021
Roof deck underlayment is a very important aspect and element that goes on a roof. This extra step ensures the life of the roof and also prevents water leakage and damage. On standard slopes which are 4/12 or more over the drip edge at the eaves, Shingle-Mate roof deck protection lays over the eave metal. Under the drip edge at the rake edge so any water that infiltrates will flow over the underlayment protection. Then, nail as needed, use only enough nails or staples to hold Shingle-Mate deck protection in place unless more fasteners are required by your local building codes.more info here
Overlap the second course 2″ extending Shingle-Mate roof deck underlayment 2″ over the preceding course. Overlap 4″, end laps should overlap a minimum of 4″. Overlap the Weather Watch or Storm Guard leak barrier by 6″ at valleys, as a second course over the eaves, and at rake edges. Install Shingle-Mate roof deck underlayment under Weather Watch and Storm Guard leak barrier at all roof penetrations.
When you are installing on a low slope roof, 2/12-4/12 pitch, the best option is to start with Weather Watch or Storm Guard leak barriers, the best protection on low slope roofs is to apply a full 36″ course of leak barrier at the eave of the roof. Or you can start with Shingle-Mate roof protection, cut the roof deck underlayment down to a 19″ width for the first course. Install 36″ course of Shingle-Mate deck roof protection, this course fully covers the first course.
Start a third layer 17″ from the eave. At 17″ from the eave, install another full course of roof underlayment protection then continue up the roof using a 17″ exposure. When installing Deck Armor underlayment protection on the deck, which is a breathable, UV-stabilized polypropylene underlayment designed to shed water. It can breathe so that it does not lock in moisture that can cause damage to the deck or building interior. Deck Armor deck protection will withstand UV exposure for up to 180 days. The primary roof covering such as asphalt shingles must be installed over Deck Armor underlayment deck protection against the deck itself.
Remember to always avoid scuffing of the leak barriers. Normal walking on the leak barriers will not cause damage. However, scuffling can compromise the waterproofing layer of Deck Armor and result in leaking. Scuffing can be caused by twisting, kicking, or heavy rubbing of shoes with weight pressure pressing the leak barrier against the deck.