It’s the Perfect Time To Inspect Roof Penetrations
by Richard K. Olson, president & technical director, Tile Roofing Industry Alliance
(Editor’s Note: Richard K. Olson is president and technical director for the Tile Roofing Industry Alliance. The association represents industry professionals involved in the manufacturing and installation of concrete and clay tile roofs in the United States and Canada, and works with national, state, and local building officials to develop installation techniques, codes, and standards for better roofing systems. Olson can be reached at firstname.lastname@example.org.)
The winter months will always bring calls for repairs, many of which will be associated with roof penetration leaks. Often, these could have been avoided with proper installation of flashing or redirection of tributary water, and can be addressed through regular inspection during seasonal maintenance before they create long-term damage. Roof penetrations such as soil pipes, vents, and roof accessories such as solar and HVAC, will often require some form of penetration through the entire roof assembly. On steep-slope roofing, this can include the cladding, underlayment, and sheathing to gain access to the attic or controlled living space below. These can create challenges in deciding how best to properly flash the system to comply with the codes. The first step will be understanding the specific recommendations for the roof cladding you are working with.
Concrete and clay tiles, when installed either direct to the roof deck or elevated on a batten or counter batten system, will always have some form of airspace beneath the tile. This helps provide increased energy benefits, as it allows a flow of air under the tile system to naturally reduce heat transfer. The space does, however, mean that if for any reason water were to breach the outer cladding, we will need to ensure a secondary flashing at the deck level can prevent water from entering the penetration hole. During the installation of tiles, this can be easily accomplished by placing a preformed flashing integrated into the underlayment that is installed to prevent moisture from penetrating the deck.
Once the tile has been laid, a top tile flashing will need to be installed in such a fashion that will allow the head lap of the tiles upslope to cover the flashing. For a profiled or curved tile, the top tile flashing will need to be a lead or other malleable metal flashing that can contour the tile surface. On flat tile profiles, a rigid metal will be allowed. The flashing will need to extend 4” onto the tile or at least 1” past the crown of a high-profiled tile to ensure water is not able to get under the flashing. We also recommend that a storm collar or sealant and a cone-style flashing be installed on the pipe extension.
When skylights come into play, how we box around to allow for proper flashing is important. One of the most common issues is not sizing the height of the curb walls high enough. For tiles, we recommend that a minimum of a 2×6 nominal or higher to allow for the tile profile and battens if used with roofing felt run up and over the curb. Roofing professionals can then install the apron, channel, and saddle back flashings less than 30” opening to direct the water away from the skylight. We recommend that the flashings go up 6” above the deck and 14” upslope. If your skylight is 30” or greater, we recommend the installation of a cricket flashing on the upslope side to help provide positive runoff and not allow pooling of water behind the curb. For profiled tiles we recommend the use of a malleable metal or weather blocking materials as closures on all installations.
When solar or other electrical equipment is installed, the roofing professional will need to work with the equipment manufacturer to ensure they are installing their supports, racks, conduits, and collector devices correctly. These installations are still subject to our deck and tile flashings when installed with our concrete and clay roofing tiles. The location of the panels and conduits should not preclude the tiles from properly seating or interlocking with the adjacent tiles. Any cut or modified tiles will need to be properly fastened and flashed to allow the full system to work as designed. Transitions of alternative roofing materials under the panels from tile will need transitional flashings to properly allow water downslope when returning to tile as the cladding.
Winter roof maintenance and cleaning is the ideal time for the roofing professional to identify areas or penetrations that might be subject to leakage. Many of the accessory products and solar panels are installed by non-roofing trained crews and can lack code-required flashings to prevent future leaks. Foot traffic in these areas can also create a breach of the cladding systems that need repaired as over time as they can significantly reduce the design life of the underlayment systems.
With proper attention to details, the installations of roof penetrations can be achieved with our concrete and clay tile roof systems and perform as designed. The fall and winter normal maintenance cycles are the right time to inspect these areas to prevent leakage where possible.