The flat roof on a friends garage has lost most of the chippings that were put on to protect it. Is it ok just to apply more chippings/grit? How deep should the grit be applied? The felt looks in good order.
You should apply a coat of bitumen emulsion first. This sets semi hard and hold the chipping in place. Sweep all the chipping into a heap where you intend finishing, brush on the emulsion in a 1m or 36" wide strip, with a soft long handle sweeping brush, then with a shovel spread the chipping evenly over the emulsion. repeat till you finish. Don't stand on the emulsion as it sticks to your foot wear and any where you walk, its a sod to get off.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.