Proper Flat Roof Installation

All roof areas shall be designed and installed to drain without holding water on the roof surface.

Proper flat roof installation.

However if you have a different type of flat roof then talk with a licensed roof contractor because you may need to add extra roof support. Then remove the rest of the roof including all the shingles. Lay the starter row of metal shingles at the drip edge and affix to the roof with metal roofing nails. To keep water from pooling at these inside corners tom rips 2x4s lengthwise on a 45 degree bevel with a table saw.

On two sides the roof abuts a parapet a short wall common around flat roofs as well as a wall for the third floor. Most metal shingles will be attached to the roof using metal shingle. Trusses or rafters should be shimmed as necessary to provide a level nailing surface. Underneath the basics flat roofs are usually constructed with a ceiling nailed to joists which support a deck usually wood in residential construction a vapor barrier insulation and a roof board.

Model building codes and good roofing practice have established a minimum slope for roofs at 1 4 12 running inches. First focus on removing the oldest shingles that are sticking out as well as any flashing or vents. The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls. If the top chords of trusses or rafters are warped or bowed install blocking to straighten.

If you come across any large nails that are sticking out either remove them and put them in your debris container or. Start at the bottom side of the gable and overlap the sections of drip edge a few inches as you work your way up the roof see figure a. Remove any nails sticking out and reposition any metal gutters so that water flows properly off the roof. Install the drip edge on the gable ends of the roof after you finish installing your underlayment.

This will give additional stability to the roof structure. This can be done with a straight piece of lumber 6 feet to 10 feet long or a long carpenter s level. However those layers make the roof very heavy. From there the flat roof system you choose will determine the materials you apply.

Start at the highest point and the furthest point from the trash container and take off all the old shingles flashing. Codes also recognize the challenges to meet this criterion in reroofing of existing buildings. Work up from the initial row starting at the lower corner in a diagonal pattern staggering the shingles to prevent gaps. If your home already has a built up roof then replacing it with another built up roof is a good idea.

If you need to reposition your gutters do so at this. Built up flat roofs are very sturdy because they have so many layers.