PVC Roof Repair
PVC (polyvinyl chloride) roofs consist of a single-ply membrane made of thick, flexible UV-resistant material. PVC is engineered to be hot welded together to withstand ponding water. It has an “Energy Star” rating when white. It is a fire safe roof, energy efficient and has long term performance for low slope applications. The longevity of a PVC roof depends on the skill of the installer and the quality of the seams. Occasionally repair is needed. PVC roofing should be inspected regularly to discover and repair potential problems.
When water sits on a roof for more than 48 hours without evaporating or running off naturally, it is called ponding. It is a code violation. Most TPO manufacturers exclude ponding in their warranties and ponding should be addressed so their warranty is in force. However, manufacturers of PVC membranes do not exclude ponding water from their warranties.
Patches in the membrane indicate previous problems in the membrane.
Lack of Adhesion
The sag in the membrane in the parapet is from lack of adhesion. The area needs to be re-adhered to prevent further deterioration and the potential of condensation and damage.
Seams not welded properly
The original installer failed to weld the seams correctly. Re-weld open seams.
Edge Flashing Missing
Roof is open at the strap that is notched in the edge flashing. If it is possible, replace the edge flashing and overlap the strap for a permanent repair. If it is not possible, seal with urethane.
Improper Flashing at Edge
The installer did not install new edge flashing that had the PVC material attached at the factory. The only permanent repair is to install the proper edge flashing and weld a PVC sheet to it. If you caulk it, it will have to be re-caulked.
Incorrect Drain Pipe
The installer used a galvanized downspout inside the structure. It should have been cast iron. Replace the drain.
Improper Drain Assembly
There is no pre-manufactured sleeve welded to the scupper. It was created at the site. Replace with a factory custom sleeve.
No Clamp, No Sealant
This detail was made at the site. Install a factor made boot and weld to the membrane. Install clamp and seal with urethane.
Separation at Penetration
This overflow was made at the site and is relying on sealant to prevent seepage. Install a factory detail so that caulking is not the primary method of sealing the penetration.
Seal On Custom Vent Open
Seal top of band clamp with urethane.
Sealant Cracked Open At Boot
Seal top of membrane and install missing clamp.
Termination Bar Not Sealed
A termination bar is used to hold the membrane against the wall and/or when it is not possible to get the membrane behind the siding or counterflashing. Sealant above creates the seal and has to be maintained.
If repairs are made with inferior materials, they may work for the short term, but will fail prematurely. Clean the surface, apply material with a reflective surface and/or repair with new materials.
Damage/Tear in Roof
Someone has damaged the membrane. Repair by welding with new materials to encase the damaged area.
The amount of time it takes for the plastic dome to break down depends upon the quality of the plastic used to make the skylight. The dome can sometimes be replaced. It is easier just to replace the whole skylight. Some manufacturers give a lifetime warranty, even for plastic domes. Glass is heavier and more expensive than plastic. Glass has a higher R-value and lasts indefinitely.
The flashing does not go up high enough for the skylight frame to overlap the flashing and the wood curb is exposed. This is open and will allow seepage. Remove the skylight and install a counterflashing on top of the curb that overlaps the flashing on the side.
Chimney Chase Leaks at Top
A chimney chase is usually a wood framed box. The pipe for the fireplace goes through the box and out the top. Typical roof chimney flashings are installed then siding covers the framing and overlaps the chimney flashing. Last a metal top is installed which allows the chimney flue to go through to the outside air. The metal top usually has a metal piece that prevents water from flowing down the opening in the metal top. The flue usually has a collar that overlaps the metal piece on the metal top. The flue usually has a metal top to prevent water from going down the inside of the flue. Any one of these items in this assembly can leak if not done correctly or if it has deteriorated. Invest all the potential issues and effect a repair.
Plastic gutters do not come with a wing. The plastic gutter company makes a plastic diverter to divert the water into the gutter. If it is not installed, the edge of the roof deck will develop dry rot.
Gutter in Stucco
When the house was built, the sheet metal installer put the gutter too close to the stucco paper. When the stucco was applied, it went around the gutter, not behind it. Over time the gutter joint can deteriorate, allowing seepage in the wall. Remove the gutter, cut the end back, reinstall the gutter end, repair the wall with waterproofing materials, then reinstall the gutter.