Do I have to remove my old, bitumin based flat roof surface (roofing felt, asphalt)?
No, it isn’t necessary to remove your old roof surface, but it is essential that you remove all loose chippings, dust, fungal growth etc and fill any cracks and depressions prior to application of Rubba-Roof Professional. Note that where chippings remain embedded, the surface area is substantially increased and will require a commensurately greater amount of coating in order to provide the minimum thickness. Allow to dry thoroughly, including the evaporation of moisture from within the layers of felt. At least 3 coats are recommended over chippings. Cut open any blisters and coat the underside with Rubba-Roof Pro and secure with felt nails, brushing out any exuded liquid rubber. Rubba-Roof Primer should be used on aged felt which has become friable but primer is not necessary on good surfaces. Apply Rubba-Roof Pro as directed above.
No, it isn’t necessary to remove your old roof surface, but you must remove all problems it has. And after you can put the new roof. But I don’t recommend you to use this material for roofing the house. The better material is slate. I have it on my house for a lot of years, and it was mounted by https://nswslateroofing.com.au/. I can tell you it is the best choice for price/quality. And after some time you can repaint in every color you want. So better think if you’re going to have a bitumen-based flat roof again.
