V8landy Posted February 7, 2009 Report Share Posted February 7, 2009 (edited) Hi I have a two story extension with a flat roof which the neighbours tell me is approximately 30 years old. Currently there are no leaks from it but it is showing evidence of curling at the edges, bubbling on the roof area and some cracking on the small up-stand around the edge. The other main point is insulation. The rest of the house loft area has in excess of 300 mm of insulation and you can tell the difference when you open the door to the room under the flat roof, it is like walking into a fridge. So I would ideally like a pitched roof (clay tiles0 like the other main roof. But due to the off set of the main roof and being at right angles to it as well + a current dormer window in the main roof, merging in the two roof would be very hard. SO I think it would be best to treat the section as a stand-alone roof ideally hip ended, and running into a valley at the joining of the old roof. I am quite a competent DIY'er and I mean more than IKEA flat packing, therefore I would like to consider this as a project (possibly next year) Is this feasible or will you laughing like the OH did when I mentioned it to her!!!! I have seen many company that will produce the trusses their design and even come on-site and measure up for you. Given the old roof is till water proof, and I am not planning to tie into the existing pitched roof, this project (as I see it) would be less weather dependant and last to a time scale given the solidness of the main flat roof (for the time being) Any tips please The area of the flat roof is approx 4300 x 5900 mm any rough costs? Would I need planning permission? / building regulation? Edited February 7, 2009 by V8landy Quote Link to comment Share on other sites More sharing options...
Fisherman Mike Posted February 7, 2009 Report Share Posted February 7, 2009 You would need both. If you are not adding a room in the attic space created why bother ? Have the flat roof replaced with a modern PVC based single ply membrane and have the insulation upgraded at the same time with a rigid extruded insulation. This can be applied ontop of the old substructure and would not compromise the existing ceiling. Search yell.com for roofing contractors who are members of the Single Ply Roofing Association. Construction work is tight at the moment so you might get a very good deal. Cheers. FM Quote Link to comment Share on other sites More sharing options...
V8landy Posted February 7, 2009 Author Report Share Posted February 7, 2009 If you are not adding a room in the attic space created why bother ? Thanks for the info. The reason for the prefrence to a pitched roof is purely down to looks. But given that it is at the back of the house and as long as the insualtion can be upgraded flat is still a possiblity. Thanks Quote Link to comment Share on other sites More sharing options...
V8landy Posted February 7, 2009 Author Report Share Posted February 7, 2009 I have just done an on-line quote from this lot http://www.countyflatroofing.com/about-us.html I nearly fell of my chair at £6200 Sarnafil Roof Assured Estimation. Area Price £ 3710.3625 Upstand Price £ 215 Perimeter Price £ 523.25 Insulation Price £ 1496.83 Decking Price £ 1496.83 Storey Price £ 300 Total Price £ 6245.4425 All Prices include VAT VALID 30 DAYS FROM-7 Feb 2009 Quote Link to comment Share on other sites More sharing options...
Imperfection Posted February 7, 2009 Report Share Posted February 7, 2009 I used to be a roofer and specialised in single ply membrane. Single ply is what you really want because provided it never gets punctured-it should last forever because it reflects harmful UV rays (which causes felt to blister & curl) and is totally maintenance free.Even when its covered in green algae,moss,lychen etc-it dont harm it whatsoever and this is why its used on high rise appartment blocks because of lack of maintenance.I know people dont like flat roofs because traditional felt is notoriously unreliable,but to change it to pitched will require planning application and can be expensive. Most people who have single ply opt for atleast 100mm insulation and this will make the room considerably warmer.This is a solid insulation usually supplied by 'Kingspan' and gets fixed to roof before being covered with the single ply membrane.The membrane itself comes in various colours like light grey,lead grey,verdis gris (green) and terracotta red.Light grey is the cheapest and most commonly used though. Check out your local papers or yellow pages for a reputable company or ask around incase someone near you knows someone and could possibly do it on the side... Its not the cheapest flat roof material,but it is 1000 times better than felt. Quote Link to comment Share on other sites More sharing options...
V8landy Posted February 7, 2009 Author Report Share Posted February 7, 2009 Thanks for your great advice, but I am realy wanting to go down the route of pitched roof simpley down to visual appearance of the roof. Quote Link to comment Share on other sites More sharing options...
mysecretlife Posted February 7, 2009 Report Share Posted February 7, 2009 Agreed pitch roofs look much better! I'm a building control surveyor for a local authority (i'll get loads of hate mail now) if you want any advice on the building regs side of things drop me a line Quote Link to comment Share on other sites More sharing options...
scifiden Posted February 7, 2009 Report Share Posted February 7, 2009 (edited) Any joiner worth his salt will pitch the roof up for you without the expense of having made to measure trusses. You can either leave the exisiting flat roof on or remove it & i'm sure only standard building regs will apply if you don't go above the height of your main tiled roof. No doubt someone on here will correct me if i'm wrong I work for a roofing company here in stoke & i would say approx £3000 to £4000 But make sure they are a reputable company, there are a lot of cowboys & indians out there You can see our company at www.steveemeryroofing.co.uk Edited February 7, 2009 by scifiden Quote Link to comment Share on other sites More sharing options...
MM Posted February 7, 2009 Report Share Posted February 7, 2009 I have just done an on-line quote from this lot http://www.countyflatroofing.com/about-us.html I nearly fell of my chair at £6200 Sarnafil Roof Assured Estimation. Area Price £ 3710.3625 Upstand Price £ 215 Perimeter Price £ 523.25 Insulation Price £ 1496.83 Decking Price £ 1496.83 Storey Price £ 300 Total Price £ 6245.4425 All Prices include VAT VALID 30 DAYS FROM-7 Feb 2009 thats a bit steep. you should be able get it done for half that. Quote Link to comment Share on other sites More sharing options...
CEREALTHRILLER Posted February 7, 2009 Report Share Posted February 7, 2009 (edited) I'm a joiner and I have to agree that a pitched roof is the way to go. If it's done well it will look like it's meant to be there and will compliment the existing roof I think you really should consider tying into the existing roof, it 'll be more expensive but as you only do these things once you'll be much happier with the finished result If you go for a double hip ended roof and have a large lead valley flashing and if/when the drainage gets blocked wth leaves etc it will fill up and cause major problems elsewhere If I was doing it myself that is what I would do :o Edited February 7, 2009 by CEREALTHRILLER Quote Link to comment Share on other sites More sharing options...
jasons gold Posted February 7, 2009 Report Share Posted February 7, 2009 I am a time serverved, highly qualified carpenter, and even if you do go down the truss route it would be still very difficult for a diy job this is best left to the professionals especially if you want the roofs to marry up . these companys that come and measure up for trusses only get about 20% right when they have to match to a existing roof Quote Link to comment Share on other sites More sharing options...
Fisherman Mike Posted February 7, 2009 Report Share Posted February 7, 2009 Get a proper quote. It will come down a great deal My Job is a Senior Estimator for a Construction company. It wont be much cheaper for the pitched roof if done properly. Quote Link to comment Share on other sites More sharing options...
V8landy Posted February 14, 2009 Author Report Share Posted February 14, 2009 I have recived a quote from a truss manufacturer of £284 for my roof. I was expecting to pay more than that in wood alone and then have to cut and fix and build up the structure! I guess they do it day in day out buy in bulk etc hence the price. I am now estimating the roof cost to be £1500 as a DIY Quote Link to comment Share on other sites More sharing options...
MC Posted February 14, 2009 Report Share Posted February 14, 2009 A truss manufacturer will normally only do the easy bits, I would be suprised if they do the jack rafter infills on the hip or the cripple rafters on the valley. They normally get somewhere near and supply the diminishing trusses and then cop out when it gets hard. I would definetly lay it back on to the old roof and have aither fibreglass valleys or valley tiles depending on your existing roof tiles. A hipped end of gable is entirely your choice but a hip looks better. Most councils do not like flat rooves any more and planning shouldn't be an issue (as long as your neighbours like you) Quote Link to comment Share on other sites More sharing options...
V8landy Posted February 14, 2009 Author Report Share Posted February 14, 2009 Neighbours are fine with it, we only have 2! Yes I know work will still be needed to do valles and merge into the roof, but the main bulk of the work is done in the ready made trusses, which do include the hip sections. But I am also planning on buying this book And costing up the job as a cut roof. I have now worked out how it will merge into the current roof, one half as a valle the other as a gable end! I know it sounds odd, but trust me that is the way it is. Quote Link to comment Share on other sites More sharing options...
cubix Posted February 15, 2009 Report Share Posted February 15, 2009 Have a search on here, great site: http://www.diynot.com/forums/ Quote Link to comment Share on other sites More sharing options...
V8landy Posted February 15, 2009 Author Report Share Posted February 15, 2009 I am allready on that forum, some help, but not that much. As the ttle says, "Diynot" they are not into DUY! Quote Link to comment Share on other sites More sharing options...
V8landy Posted May 30, 2011 Author Report Share Posted May 30, 2011 (edited) Well 2 years and 3 months later we have FINALY started this work! Started on Saturday, ripped off old flat roof felt and timber deck, no rot below at all. Knocked out bricks and set wall plate, got all trusses up and must of hip end done, by end of sunday. Rain stopped play today, but will be chasing off plaster in room below for wall plate straps to be fixed on. Waiting for rain to stop to get on with the valley section into main house. Building control guy is coming Wednesday, but this is not a sign off pass or fail as we are doing on a buildings notice, so more just guidance from him and so he can see we are doing it correct, and sign of f inlay as job lot at end. Only thing he is interested in is will it blow off, is there enough ventilated and insulation. Pre made trusses helped a lot. Edited May 30, 2011 by V8landy Quote Link to comment Share on other sites More sharing options...
lincs1963 Posted May 30, 2011 Report Share Posted May 30, 2011 looks to be coming on ok mate. Wall plate restraints are not a requirement any more apart from garage roofs. gable restraints are still required at minimum 2metre spacings. i reckon you will be pleased you took this route as opposed to the flat roof, it will look much better and be maintenance free. regards, Neil. Quote Link to comment Share on other sites More sharing options...
V8landy Posted May 30, 2011 Author Report Share Posted May 30, 2011 looks to be coming on ok mate. Wall plate restraints are not a requirement any more apart from garage roofs. Thanks BCO, wants to see wall plate restraints! Just finished the chasing out of the plaster for them. Brighting up now, so soon should be able to go out. Think we will be working till 9 or 10 tonight. Then weather looks perfect for rest of week. I have Uncle and father in law (all builders ) helping me. Quote Link to comment Share on other sites More sharing options...
Vince Green Posted May 30, 2011 Report Share Posted May 30, 2011 (edited) Many flat roof extensions from 30 years ago were poorly done but on the subject of it being cold, roof insulation was almost certainly poor (even non existant?) but also wall insulation. You can improve the roof insulation without going up simply by adding a 6" layer of insulation to the top of the existing roof and re-covering it, but the larger area of walls, if the have no insulation will still draw the heat out of that part of the building unless you are prepared to lose 4" from the inside to clad the walls. You can clad the outside but it may look odd and the wood or plastic to go over it is very expensive. Do you get condensation and black mound inside the extension? Feel the walls in the winter, are they cold to the touch? Edited May 30, 2011 by Vince Green Quote Link to comment Share on other sites More sharing options...
V8landy Posted May 30, 2011 Author Report Share Posted May 30, 2011 I do not like flat roofs full stop regardless of how well they are insulated, hence the pitch roof we are adding. I have also removed the wood end cladding, and replaced with white upvc wood grain effect. I also took the opportunity to increase the insulation, not only in the current wall thickness, but adding a stud wall on the inside, thus making the wall 10" thick. Breather membrane was added under the cladding as per spec. There is and never has been any mould in that room, the main walls have cavity fill in. We have just got in having worked from about 5pm when the rain stopped. We are now ready tomorrow to work on the section joining to the house. Things are progressing realy good, and it looks great Quote Link to comment Share on other sites More sharing options...
V8landy Posted June 4, 2011 Author Report Share Posted June 4, 2011 1 week later. BCO signed off structure. I have worked out that in the week we have done nearly 3 weeks work @7 hr days. Just the hips, ridges and valley to sort out now. Very pleased with the results. Quote Link to comment Share on other sites More sharing options...
Fisherman Mike Posted June 4, 2011 Report Share Posted June 4, 2011 Looking Good.... Quote Link to comment Share on other sites More sharing options...
Paul T Posted June 4, 2011 Report Share Posted June 4, 2011 A great improvement It looks much more like a natural part of the house rather than some odd-looking box on the back Quote Link to comment Share on other sites More sharing options...
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