This guide describes the procedures of complete flat roof demolition, done with the intent to either completely rebuild the framing of your flat roof, or to convert it to a steep slope roof. This may be done if your flat roof construction creates unsolvable roof leak problems, such as ponding water and other roof leaks, or if you want to convert your roof type to a sloped roof for aesthetic reasons – for example if you want to add skylights or a metal roof.
Removing a Flat Roof
Method is key in the removal of flat roofing, assuming you want to work as quickly and safely as possible. An old flat roof, damp can quickly become a problem; it permeates through the surface layers and causes the wooden joists that hold up the roof to rot. If this has happened, then chances are high that your entire roof will need to be removed. Depending on the size of the roof that you have to take down, it is quite likely that a lot of debris will be generated in the course of the demolition. You should prepare yourself for this prospect in advance and order a skip before you begin work to save on clean-up times later on.
Safety should always be your first concern when approaching any demolition job, particularly when the demolition in question involves working at height. You have to make certain that you have a safe way on and off the roof, either by way of ladders or scaffold towers where admissible. The roof also needs to be checked for stability if you are going to need to do a lot of walking across it. If you find that stability is in question, you will need to use working boards to reinforce it, and to prevent yourself from putting your foot in it (and through it).
Begin the job by taking down the guttering. If you have more modern types of plastic guttering, it is quite likely to be a simple case of unclipping easily. Older or sturdier types of guttering (the types that the burglars are always climbing up in films) are likely to take a bit more effort to remove, but it should still be no more than a matter of loosening some screws. If you will need to reuse the guttering, then you should store it in good order and lay it out in a place where it won’t get crushed (the better care you take over this task, the easier it will be to reinstall). If you aren’t going to reuse it, chuck it in the skip as you go.
With the guttering gone, you need to remove the fascia boards. Roofs that are covered in chippings (gravel) will need to be swept clear before you remove the roof covering underneath (stone chippings and gravel are used as ballast for the roof covering and also serve to reflect the UV rays that can cause damage to asphalt roll roofing). Again, if you plan to reuse the gravel then you will need to bag it up in rubble sacks and remove it from the roof for safe storage. Avoid overfilling the sacks, as overly heavy sacks can make getting off of the roof with them a hazard. If not reusing them, skip them.
After the stones are gone, you will need to take up the roof felt. Begin by prising up the sides of the material, tearing it away in sections and disposing of it immediately in the skip. Be sure to use work gloves while undertaking this task, as well as safety goggles and any other relevant safety equipment. After the felt, you need to take off the supporting boards (roof substrate). A number of different materials may have been used to board the roof, but most will be removed in the same way. Prise them off of the joists with a wrecking bar and remove any hazardous nails as you go to prevent injury.
With the boards off, next you need to tackle the joists. You should be able to remove the joists using only a wrecking bar (flat bar), but you may also need to remove the furring strips if you are planning to reuse the timbers (assuming they are safe to reuse, i.e. they are free from rot and what not). Only people who are confident and competent should undertake this kind of demolition job, so if you are unsure about it then you should seek professional assistance. Houses with flat roofs are likely to be harder to insure than those with standard roofs (maybe this fact is why you want to remove it) but you can still get the flat roof house insurance you need with a non-standard insurance provider.
This flat roof removal guide is a guest blog post submitted by Zoe Restick.
Written by Leo - roofer with a vision. Follow Leo on Google+