How To Patch A Leaky Corrugated Metal Roof

Corrugated (paneled) metal roofs are commonly installed on sheds, garages, and it is still installed on some residential housing. If you have a corrugated metal roof, you come to appreciate its low maintenance and ease of installation. However, they are prone to wind damage that moves the panels, causing a leak. Here are some tips on fixing leaks on a corrugated metal roof.

Make Preparations

For this project, you will need:

  • an extension ladder
  • safety harness
  • tool belt
  • hammer
  • nail bar
  • wire brush
  • paintbrush
  • cordless drill
  • urethane roof cement
  • aluminum screw nails
  • coating for metal roofs
  • glass membrane roof patch
  • putty knife
  • fabric shears
  • galvanized steel screws

Set the extension ladder on firm, level ground. For extra safety, wear a harness, or have someone hold the ladder for you as you climb. Place tools in a tool belt, and don't open the roof cement until you get on the roof. Be aware of power lines while you work.

Check the Fasteners

Common sources of leaks on corrugated metal roofs are damaged fasteners. Clean debris with the wired brush, and remove nails with the nail bar. Hammer an aluminum screw nail into the place of the nails that you removed. If you spot nails with rust on the head, use the cordless drill to insert a galvanized steel screw next to them.

After you drive in a nail or screw, spread a coat of urethane cement on it with the putty knife. Check the caulking around the flash edge of pipes and ducts that run through the roof for gaps. Brush loose caulking away with the wire brush, then spread caulking on the upper section of the flashing area and the pipe or duct foundation with the putty knife.

Inspect the Panel Overlap

Another cause of leaks on a corrugated metal roof is panel overlap. Inspect the overlap of the panel edge for gaps and use a paint brush to spread a layer of metal-based roof coating around six inches from each direction at the overlap of the gap. Insert a piece of glass membrane fabric cut to size with the shears over the area. Finish with a layer of urethane cement, spreading it over a six-inch area of the surrounding roof to cover the membrane.

Regular roof inspections will help you keep watch on corrugated metal roof leaks. Examine the roof especially after heavy winds or rain, and make certain gutters stay free of clogs so water flows properly. If the roof is badly damaged, consider contacting a roofing company for a new roof installation.