In the U.S., most roofs are made of asphalt, which needs to be replaced every 20 to 30 years. However, you can make your asphalt roof last longer by inspecting and maintaining it regularly. One of the key issues is to make sure that the pipe flashings are in good condition.
Flashings are the metal or plastic pieces that seal the pipes that run across the roof. They are essential because they prevent water from seeping around the pipes and causing damage to the roof or house. In this article, we will explain what flashings are and what their benefits are. We will also discuss some things not to do when installing or maintaining pipe flashing.
What Is Pipe Flashing
To find out what a Pipe Flashing is, we will show you by means of the Kynar® coated 24-gauge G-60 galvanized. The Ultimate Pipe Flashing® (UPF) is a high-performance flashing component engineered to sustainably seal the plumbing vent pipe penetration through a roof surface.
Created as a durable assembly for steep slope roof use, the patented design incorporates an integral precision compression seal to the vent pipe, allows installation on slopes from flat to 18/12 pitch, and provides industry leading flashing margins to shingles for proper and complete rain shedding installation. The UPF can be used with any steep slope shingle style roof covering including asphalt shingles, slate, tile, cement tile, cedar shake, and more. This Kynar® coated 24-gauge G-60 galvanized steel sheet version is exceptionally well suited for use in all but the most corrosive high chloride environments, such as coastal or beachfront buildings and is an excellent choice with all available roof covering materials like asphalt shingles, slate, tile, or cedar shakes
Instructions & Recommendations for Use
Every UPF is packaged in a protective carton which is imprinted with bilingual instructions for proper installation of the UPF to the roof penetration. The installer must determine the vent pipe material and size. If the vent pipe material is not Sch. 40 PVC DWV pipe, such as copper or cast iron, then a Lifetime Tool® EASYSleeve® or EASYFit™ may be required for proper long-term performance. The seal to the pipe on a UPF is a precision engineered compression seal for each pipe size encountered, available to seal Sch. 40 PVC DWV pipe in 1¼”, 1½”, 2”, 3”, and 4” sizes that are commonly found in residential and light commercial roofing markets. The installer must ensure that the correct UPF is installed for the given penetrating pipe size.
It is recommended that the UPF be delivered to the pipe penetration on the roof in the original carton. In this manner the installer can double check the size and will have the carton (with bilingual Instructions) at the installation site for reference. A rigid molded PVC compression collar is supplied in each UPF carton.
This compression collar is engineered to live at the top of the flexible seal bushing between the two molded bead rings (as shown on the instructions illustrations on the carton) and must be installed thereon before installation onto the vent pipe. The supplied lubricant towelette must be used to wet the interior surfaces of the flexible seal bushing and the external surface of the vent pipe prior to installation. Once installed onto the vent pipe, with the compression collar on
the flexible seal bushing, and with the flashing plate seated firmly on to the roof surface, the nails can be applied in the slots provided on the flashing plate of the UPF to affix the flashing to the roof.
Benefits of using the Ultimate Pipe Flashing
The engineered flashing assembly utilizes materials known for long-term outdoor exposure, including:
- Kynar® coated 24-gauge G-60 galvanized steel sheet for the flashing plate
- High consistency molded silicone elastomer for the flexible seal bushing
- Exterior grade, UV stabilized, rigid PVC for the compression collar
- Proprietary silicone lubricant formulation for the installation towelette
The patented compression seal technique provides a precision lifelong seal to the pipe for each Sch. 40 PVC DWV vent pipe size encountered. One size does not fit all! The flashing plate is produced with generous side and top margins to allow substantial overlap with the shingled roof covering materials, providing an excellent rain shedding finished installation. The flexible seal bushing has been developed to accommodate roof pitch variations from flat to a pitch of 18/12 without further modification or additional installation labor.
Materials of Construction
Flashing Plate – Deep drawn and stamped Kynar® coated 24 gauge G-60 galvanized steet sheet with a classic dark bronze finish. Meets or exceeds ASTM A635-09 standards, providing superior corrosion resistance in all outdoor environments except coastal and beach front homes and buildings.
Seal Bushing – Molded from a high consistency silicone elastomer proprietary formulation specific for this application, conforming to ASTM G-154-06 for resistance to UV exposure and ASTM D-1149-99 for surface resistance to ozone. Minimum wall thickness of 3.6mm (0.144”) ensures long-term fatigue resistance to daily thermal gradients.
Compression Collar – Molded from a rigid PVC compound specifically compounded for long-term exterior exposure applications, including UV stabilization.
