How to conduct adherence tests with Metalseal 20 - the BBA Approved metal roof coating system from Liquasil Ltd
When carrying out roof coating works it is important to conduct adherence tests, to ensure that the product (ours or anybody else's) will fully adhere to the substrate. In this training video, we show two adherence test methods that can be employed with silicone coatings. 1) The pull test and 2) The push test. Because nothing will stick to silicone coatings, we coated a sample area with Metalseal 20 and laid a small strip of polyester fleece within it. Once cured, we then went back to site and pulled the polyester strip. If the silicone breaks and leaves the majority of the silicone on the roof surface, this is a positive test and coating can commence. With a push test, instead of embedding a fleece, you simply coat the surface and then, when the product is cured, rub the edges of the coating with your finger or thumb. If the coating doesn't peel off (as opposed to breaking the surface), this is a positive test and coating can commence. Some coatings can be adherence tested by placing strong adhesive tape to the surface and then rapidly pulling it away and checking to see if any of the new coating is visible on the back of the tape. This is not possible with silicone coatings, since nothing will adhere to the surface.