How to

Here you'll find a selection of helpful how-to guides and videos to help you achieve that perfect finish for your next project. To continue, please specify the area of the house you are working on from the interactive map below.

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    • How to seal a leaky roof or gutter

How to seal a leaky roof or gutter

Leaking roofs and gutters can cause your property serious damage and should be fixed straight away. Even a small roof leak can quickly lead to bigger problems like mould, rotting insulation, electrical faults and damaged ceilings. Small holes and broken seams in gutters can also allow rain to seep into the roof. The good news is that once youíve found the leaks, they're easily sealed with Poly Roof & Gutter Silicone Sealant.

You'll need:

  •  Poly Roof & Gutter Silicone Sealant 
  • A caulking gun 
  • Scraper 
  • Mineral turps

Finding the leak 
For a leaking gutter, first clear away any debris and avoid pushing it into the downpipes. Once youíve cleared the guttering, hose the gutter in the direction of the downpipe to make sure itís not clogged, then inspect the gutters for cracks or rusty holes.

For a leaking roof, inspect areas on the roof that are higher than where the leak has entered the ceiling and look out for cracked tiles or penetrations such as roof vents. It may be necessary to run a hose on different sections and have someone inside call out when the leaking starts. 

Once you've located the source of the leak, you can effectively seal it by providing a watertight barrier with Poly Roof & Gutter Silicone Sealant.  This non-corrosive product bonds to most materials including metal, aluminium and masonry.  


  1. Prepare the area. Wipe away loose particles and scrape off old silicon. Clean the surface with mineral turpentine.   
  2. Load your caulking gun. Cut the tip off the cartridge and then cut the nozzle at a 45 degree angle to give the desired bead thickness. Place the cartridge in the caulking gun and fit the nozzle.  
  3. Apply the sealant. Hold the gun at a 45 degree angle and dispense the sealant ensuring that it is pushed right into the gap, hole or joint. 
  4. Smooth the sealant. Smooth off the sealant with a spatula dipped in detergent. Remove excess sealant immediately with a cloth dampened with mineral turpentine.  
  5. Drying. The silicone will skin in 5-8 minutes and will be fully cured in 24 hours. 

If you haven't used your whole cartridge, you can re-seal it for another job by popping a small pencil or wooden rod in the end and putting tape over it.

Avoid breathing vapours and contact with skin and eyes.