How To Apply Roofing Topcoat
Top coating the roof Apply Topcoat at a ratio of 0.5-0.6kg per m2, this ensures the correct thickness and will prevent cracking under fluctuating temperatures
Quickly understand how to apply roofing topcoat to a flat roof. The Topcoat is a resin and should be treated in the same way as the base resin. It requires the addition of a catalyst for it to cure. Always try to apply the topcoat immediately after the laminate is semi-cured (can be walked on, no stickiness) If this is not possible then ensure the top coating is carried out within 24 hours to gain good bonding with the laminate.
If the top coating is left longer than 24 hours then wash down the laminate with acetone to gain a good cross-polymerisation of the topcoat to the laminate. Remove the lid and stir the topcoat well before use. Ensure the styrene and wax at the bottom of the tin is fully mixed in. Pour out into the mixing buckets enough topcoat to cover the perimeter of the roof (including the edge trims.) Use a 2½ Polyester roller to coat the trims.
A roller will get a better and more even finish than a paintbrush.
Roll the topcoat along the face of the trim.
Hold the roller at an angle to the bottom of the trim to cover half of the radius return on the front of the trim. To protect the fascia from the topcoat, hold a piece of flashing trim against it as you topcoat the radius on the underside of the trim. Calculate how much topcoat you will need to use to cover the main body of the roof. (See material estimator in the Commercial Manual.) Add the required amount of catalyst and stir well. Using the 7” polyester roller, cover the remaining laminate with just enough topcoat for the fibre pattern to be visible. Do not coat the roof too thickly or the topcoat will crack. If a coloured topcoat is needed rather than the standard cool grey or dark admiralty grey, a colour pigment will need to be added to a clear topcoat.
Cleaning Tools and Equipment
Buckets can be re-used for many jobs. When each mix is finished, coat the inside of the bucket. When the resin has cured after approximately 30 minutes it can be peeled out, leaving the bucket like new and ready for the next job. Paintbrushes can be dropped into a re-sealable container of acetone and left for the next job. Use only paintbrushes that have unpainted or uncoated handles, as the coatings will come off and contaminate the resin. Polyester rollers have sleeves that are removable. It is too time-consuming to clean the roller sleeves. Unscrew the nut with pliers and drop the used sleeve into the bucket of used resin. Either use disposable latex gloves when handling catalysts or resins or clean hands with hand cleaner. Do not clean your hands with acetone. wipes are also a useful addition to your toolkit. As well as cleaning hands they are good for removing resin from windows and fascias.
