Single-ply membranes, such as PVC and TPO, are ideally suited for commercial roofing systems because they are durable and easy to work with, come in different thicknesses, are watertight, and can contain additives for flexibility, UV protection and color. However, as with all roofing systems, they require regular inspection and upkeep.
It is not uncommon for storms, debris or man-made objects to puncture or tear a single-ply sheet, which if not immediately addressed can lead to water damage and other issues. Fortunately, with the right tools and technique, this damage can be quickly remedied by hot-air welding a patch over the hole or rip.
Following are instructions on how to hot-air weld a patch onto a single-ply roofing membrane.
Step 1: Collect Your Tools
To weld a single-ply patch in place, you’ll need the proper equipment:
- Hot-air hand tool—A handheld heat source that can be easily moved around the patch to access all sides of the patch, such as ELITEAIR.
- Overlap nozzle—Flat-tipped nozzle that lets you easily apply hot air directly at the point where the roofing material and patch come into contact.
- Pressure roller—This will help you apply the necessary pressure to the heated patch and roofing material to ensure that a strong bond is formed.
- Metal prod—Small metal pointed device, used to make sure the seam edge is completely welded.
Step 2: Create a Patch
Using the same material as the roofing membrane, take a razor blade and cut a patch to place over the puncture or tear that stretches out 3-4 inches past the hole in all directions.
Step 3: Clean the Patch and Surface Material
Next, make sure both the patch and surface material are free of any debris, dust, oil or other contaminants. These contaminants can negatively affect the weld quality, and lead to a weak bond or no bond at all.
Step 4: Weld the Patch in Place
To weld the patch in place, follow these simple steps:
- Secure the overlap nozzle to the hot-air tool.
- Preheat the hot-air tool to the required air temperature. This will vary based on the plastic material and environment, so always perform a test weld before starting on the final patch.
- Place the patch directly over the puncture or tear so that there are several inches of overhang on each side.
- Insert the overlap nozzle between the patch and roofing membrane. In the other hand, press the pressure roller on top of the patch where the overlap nozzle ends.
- Work your way around the patch, making sure to weld the entire surface area to the roof sheet, especially the edges. NOTE: Effective plastic welding takes proper technique, which comes with time and practice.
Step 5: Test the Patch Seam for Gaps
Once complete, let the patch cool for several minutes, and then run your metal prod along the seam edge to ensure there are no gaps or voids. If there are, re-weld that area.
Even the smallest gaps or voids can allow water in, which over time will widen the problem area and eventually lead to water damage.
If you have any questions about this process, or would like more information on hot-air hand tools, please contact one of our technical representatives at 844-862-7880 or email firstname.lastname@example.org.