Two Installations That Keep Your Flat Roof Penetrations From Leaking
If you have a business with a flat roof, then you may be concerned about water leaking through the rubber, PVC, or bitumen roof structure. Water may pool on the roof before it has an opportunity to drain, and this is a real concern around roof penetrations. Penetrations are areas where structures, like skylights, sit on the roof, and these areas can leak if they are not sealed correctly. Sealing should be completed during the initial installation of the flat roof, but it can be completed after installation if your roofing expert did not secure penetration protectors. There a quite a few different types of protectors or seals that can be installed, especially when it comes to vent pipes. Keep reading to learn about a few.
Pipe boots are some of the easiest and simplest penetration protectors. The boots look like a safety cone with a flat bottom and a round inverted cone shape that sits on top. The cone part of the boot is separated into different circular sections that build in size from the top of the cone to the base. These different sections fit around different sized piping vents, and the tip of the cone is cut down so the boot sits tight around the pipe. For example, if the vent pipe is a typical or common one, then the one and one-quarter inch diameter section will be found and the smaller sections above it will be cut away. Cutting is relatively easy since the boot is made out of thermoplastic polyolefin. Thermoplastic polyolefin, olefinic elastomer, or TPO is a mixture of thermoplastic, rubber, and a filler material, and the material is pliable and flexible.
Once the cone part of the boot is cut away, it is slipped over the vent pipe and the base is set on the roof. Some boots will come with a butyl rubber material on the bottom of the boot, and the material will self adhere. If the boot does not come with the adhesive, then a similar rubber adhesive will be used to secure the base. The boot will also come with a pipe clamp. This clamp slides down the top of the boot and secures at the base of the boot and the vent pipe. The clamp helps to keep water from seeping down inside the boot and leaking through the roof of your business.
Some pipe vents will be surrounding by simple rain collars or flashing material, and the edges of the flashing are placed underneath the roofing membrane. However, if your vent is oddly shaped, angled, or difficult to enclose for some reason, then prefabricated materials may not create a good seal around the pipe. In this case, your roofing expert may choose to add something called a pitch pocket. This pocket is used to build a form around the pipe that is then filled in with a sealer material. Sealers are usually made from either rubber or polyurethane.
To install the pocket, a form is centered around the exterior of the pipe. This form is made from aluminum or polyurethane. A chalk line is drawn around the pocket form and then removed. A fast curing elastomeric adhesive is placed around the chalk line and directly around the edge of the vent pipe. The edge of the form is set over the adhesive and left to dry for several minutes. Once the curing process is completed, the rubber sealer is placed in a caulk gun and then squeezed into the open pocket area created by the form. Sealer is added until it sits flush with the top of the form.
The sealer is left to cure in the pocket. Afterwards, the edges of the sealer and the adhesive around the bottom of the form are trimmed smooth. This helps to move water away from the pocket so it can drain from the roof properly. For more information, contact a business such as Select Exteriors.