Tony K

Evening everyone. I had planned to commence my self build in spring of this year, but a combination of circumstances meant that I only received my self build mortgage offer today. I have also discovered a couple of brand new hurdles that I have to clear: 1. Building control need some extra details from the engineer regarding the foundations. I can start work in advance of approval at my own risk, but the footings are unusual and complicated (steel screw piles, heavy clay soil and trees), and so these aren't standard details. 2. Having done two thirds of the land level reduction I've established, as I knew I might, that the clay soil won't play nicely with the soakaway. I will need a drainage engineer to design a solution, and probably need Thames Water to agree to me connecting my downpipes (and possibly some limited land drainage) to the main drain. 3. A tedious technicality has arisen regarding whether my existing bank or the self build lender gets to have first charge on the site. I have no idea if these things will take days, weeks or months to resolve. What I do know is that winter waits for no man. My questions are... How big a difference does it actually make to build in winter rather than summer? What are those differences (costs, time, quality?). If I can resolve these issues in the next two or three weeks I might just commence. If not, would I be foolish to begin when I can postpone until spring? It's a small house, 110m2, and should be an 8 month build. Any advice gratefully received. Thanks.

Ah, understood. Thanks.

Very useful thanks. Rubber roofs just seem more appropriate for a DIYer in winter. What makes the solvent adhesive up stands such hard work?

Steve is the knowledge roofer I referred to a couple of posts ago! Interestingly, he offers a consulting service for DIY roofers which I may well make use of.

Seems pretty easy actually... There are also various instruction videos from suppliers that show similar techniques.

Thanks for everything posted on this so far. Regarding the two great threads that @Ferdinanddug out, my original concern was avoiding exactly the issues that affected the schedule, budget and mental health of @andyscotland! My own roof is 100m2, and so erecting a scaffold structure over the whole lot seems unrealistic, if only in cost terms. I have looked into rubber roofing as suggested. I feel I now have three options: 1. GRP. 2. Liquid rubber roofing. 3. EDPM in sheets. 1. As a DIY option GRP seems fraught with pitfalls, especially in the winter. I have found a series of very clear educational videos and was confident I could follow them, but not necessarily quickly enough to do the job well on dry days between rainy periods, which it seems is what roofers do. Pre-forming the boards as proposed by @SteamyTea is an interesting idea, but requires a reasonably large workshop, which I don't have. One roofer who appears knowledgeable (and expensive) informs me that he rarely uses GRP now, almost exclusively rubber in one form or another. His thinking is that whilst GRP has a nicer look to it, doing it well requires far more care, attention and cost than is commonly allocated, making rubber the better option in comparison. He basically thinks that there are a lot of bad GRP roofs out there where corners have been cut. 2. Liquid rubber roofing seems almost too good to be true. From what I can see, you pre-form the edges and joins as with GRP, then mix up the stuff and paint it on: HOWEVER, a manufacturer I spoke to informed me that the product doesn't like the rain much more than GRP does, and though the rubber is breathable and will eventually allow bubbles etc out, that doesn't help stop problems with bonding. As with GRP, I would be left trying to get the deck on, and the finish too all in the space of one dry period. Possible, but not ideal. 3. Rubber sheet roofing looks good, and whilst this chap appeared concerned about the weather when laying it..... ... it does at least go down very quickly and seems to protect the deck the second you lay it down. I presume I could even leave the sheet sitting loose on the deck as a cover either overnight once I finish the deck, or on the day of the job if rain does suddenly turn up? Any ideas and suggestions gratefully received as always! Thanks

Is there a market leader I can start with that you know of at all, and is it as good as (properly done) GRP?

Does anyone have any preference re tounge and groove or straight edge boards?

Here is the basic plan, nothing too complex. As @joe90 suggests, I was going to use pre-formed edges etc.

L shaped building with a split level roof, so basically two large separate rectangles each about 50m2. Only other complications are a series of small rooflights.

If that works then it's probably the best of both worlds. Are you thinking of doing the final top coat on each section as I go along?

That's useful, thanks. What size board are you thinking of for that sort of rate of productivity?

I'm in Epsom, Surrey. I'm not at the roofing stage yet. I have been delayed in getting out of the ground by the remarkably slow and poor performance of the mortgage lender and brokers - thats why I'm asking these questions about the roof; whereas I had planned to do the roofing in the clear, bright days of September, it now looks like a December job. I don't have a large shed. I was just thinking about that. I would need a fairly large, dry place to prepare the boards and let them dry. It might be that I could hire a gazebo for the purpose.

I was going to say that it sounds like I could pack my whole roof up and bring it to you, though I reckon the poor old Toyota Prius might strain a little if asked to carry a 100m2 roof. I presume the fully treated and coated boards would be screwed into place as per normal, with the screws going through the coating etc, but then being covered over by the subsequent strips?

Thanks. So even the topcoat can be done in stages? Would it not be stronger if done in one continuous operation? Don't suppose there are any good youtube videos around showing this technique? There are quite a few very useful ones showing the normal method and I would feel confident following them, but you're talking about next-level stuff!

That's interesting. If I am using 18mm t&g osb would I just literally apply a sheet of matting to each board, let them all go off, then fit them in place? Would I be against the clock once I begin applying the matting to the boards? I understood that it was better to get the topcoat on within a short time of the matting sheets?

Thanks chaps, good advice and understood. So my safest way is some sort of cover (scaffold being the best, and perhaps only viable option). If I were to decide to risk it without a cover, its not just a case of it not raining on the day. I need to ensure that the deck is thoroughly dry before I start. A feature of my design is that the roof is very simple to build. This is so that if, by that stage of the project, I need to save money I can do so by building it myself (with family roped in). This will take longer than if a roofer did it of course, and also mean that the deck is out under the weather for longer. I suppose I could build the deck, insert the grp edging forms and upstands, then if any of it gets wet place a ventilated polythene sheet over it all to dry out thoroughly whilst I wait for a couple of clear days to do the resin and topcoat?

Thanks. I completely understand the second bit! There seems to be some advice on a few grp manufacturers websites that if it starts to rain you should stop work and pull a rain cover over the area. It doesn't say that rain is anything other than a bad thing, but it also doesn't describe rain as fatal. I can understand that full on rain will be a problem, and that the surface should be dry before you get going. I would of course check the forecast before getting started, but the website advice suggests that which instinct suggests - it can't be the case that every grp roof is made only in summer or under a cover? Are roofers just risking it I wonder? If so how great is the risk? I understand that it cures pretty quickly, so am I right in thinking that all I need is one clear day? Thanks

I suppose the other angle on this is: how weather sensitive is grp in reality? I appreciate that the instruction videos and manufacturers details specify dryness, but with the changeable British weather plenty of folk must get caught out by unforcasted rain. How problematic is that when it happens?

Sounds more expensive than hiring a tent?

Hi My SB is a 100m2 flat roof bungalow for which I intend to use grp. I've tried to program work so as to avoid roofing in the winter but the mortgage company have other ideas it seems, leading me to consider hiring a marquee or tent to bridge over the building and keep rain off whilst roofing. The building is an L shape, and no part of it is wider than 5.5m. Has anyone hired a gazebo or marquee to sit over a roofing project? Any pros and cons based on experience? Ta

Thanks all. Yeah it's small, but so is the house and the garden. Every inch of every part of the whole thing has been planned meticulously, and the office is no different! Cheers. Right now the only thing I need to think about is whether to dig out foundations for the office at the same time as the house footings. If even a brick office would only require fairly shallow footings then I can afford to forget about it for now and make a decision later.

Thanks @Declan52 I had originally planned to do exactly as you suggest, it's really just an aesthetic choice on my part to go for brickwork on the outside. Perhaps I'll just talk myself around to using timber instead. Cheers

Cheers Mark. I'm not familiar with insulated slabs really. I presume the insulation sits under the whole thing, including the walls and can take that weight without becoming compressed? Is there a depth of excavation for the hardcore you would use (edges and centre)? Thanks

Thanks. What sort of thickness would you propose, and would you bring the edges down a little deeper than the centre?