Tom

Hi all, looking some advice on the question of vapour barriers. Out roof make up (from outside to in) is 150mm composite panel (essentially PIR sandwiched between sheet metal) 200mm rockwool plasterboard I had planned to tape the internal seams between the composite sheets for airtightness. Do I also need a vapour barrier? Many thanks Tom

That's a great looking house (the bits they show anyway. Especially the walk-on glazing

Roger that. Bit the bullet and bought another 9 months. Project manager reckons we should be in by end January, which perhaps is a little optimistic...

So out site insurance expired the other day, and while I was pretty much the only one working on site for over a year it seemed like a reasonable thing to have. We now have a project manager starting with main contractor and subbies in a few weeks. They have their own liability insurance, but do I need to continue my own site insurance too? I will still be working on site where I can. Thanks all

It's what the I was advised to do by my local Nudura distributor

Hi all, looking at buying the membrane to cover our nudura walls. These walls will be battened, then the membrane put on, then batten over the top, so there will be an air space behind the membrane. I've been looking at the Tyvek Housewrap but this says it "Should be surface applied, fixed directly to sheathing ply /OSB, insulation or blockwork". Is it OK to use stapled to battens, or should I be looking for something else? Thanks all

On the plus side we actually have a proper firm starting this coming week to redo the lead

Building control had a look and said was shoddy, but as expected wasn't really in their remit to comment/enforce. Went back to original guy: came back with a list of excuses which boils down to: - I hadn't bought him the correct stuff (I bought whatever he asked me - lead, timber etc etc) - I hadn't supplied him with architects plans of the roof (this roof make-up ie steel rafters, z-purlins etc is what he came up with himself, and deviates from the architects plans which are for a timber roof structure, and anyway, does the architect need to supply drawing indicating the effing lead should be oiled, welded expansion gaps etc??!) So basically it's my fault as I stupidly assumed that a professional with years of so-called experience who said they could do the job was actually capable of doing the job. You live and learn.

I'm looking at airtightness tape now too, is there any reason why I should use the Tescon over this stuff? https://passivehousesystems.co.uk/product/gerband-586-airtight-tape/?utm_term=&utm_campaign=P-Max+Test&utm_source=adwords&utm_medium=ppc&hsa_acc=4901615203&hsa_cam=20355723828&hsa_grp=&hsa_ad=&hsa_src=x&hsa_tgt=&hsa_kw=&hsa_mt=&hsa_net=adwords&hsa_ver=3&gclid=Cj0KCQjw2qKmBhCfARIsAFy8buK_6Os1ItUfZI-IGCyuty8_T91HUY4t783aNEKLQRPHaEp4tvBgUfgaAmgUEALw_wcB Any one used it before? Only £10 for a 6cm x 25m roll

Agree render or brick slips is probably the done thing but that Easyboard stuff, if it's appropriate, would be far cheaper than render etc at only £10 a board - and easily DIY-able. Could do a 40cm high plinth and get a 2.4m run out of each board. Would be good to see the board in person before pulling the trigger, though would only be a £350 gamble for our 85m perimeter...

By 'eck that BluClad is £81/sheet!

Unfortunately the Nudura colour is a bit more noticeable, and our chickens love to peck at it, so needs something to cover.

That's interesting, will have to have a look

I was just going to screw it to the Nudura, then it can always be removed/replaced if it needs to be

Hello all, just wondering if anyone has experience using cement board as an external cladding. We will be cladding our house with a mixture of wood and currugated sheets, but will have a plinth running around the base, approx 30cm high, that I plan to clad in a cement board. It will be buried a little bit to completely cover the Nudura. I've been looking at this stuff: https://insulation4less.co.uk/products/easyboard-1200-x-800-x-12-5mm?variant=42173328195637 which says it is suitable as "exterior sheathing board". Two questions: any reason why this isn't a reasonable thing to do, and any other recommendations of board to use? I need something without writing on it... Thanks all

Update: we had a proper roofer round and he actually laughed when he saw the leadwork. Main problems are: - seams in the gully sealed with leadmate, this would last a few months according to him. They need proper expansion joints welded in (https://www.t-pren.com/) (or stepped as per @makie 's advice above) - none of the lead has been oiled/sealed, so it's oxidised - most of the lead needs to be scrapped - areas where the lead has been dressed in the valleys is done badly, needs to be cut/welded His quote to do the above was in the region of 2k +VAT The membrane still leaks like a sieve but I'm going to get that redone. So, I had a chat with the original guy and he's still adamant that the work he has done is good. He wants building control to come out and have a look - which I have arranged for Thursday - but not sure they will be very helpful or would even be in a position to take a view on the leadwork. Is it a thing that Building Control would take a position on? Also, are there any standards etc that I can quote which shows the requirement for expansion joints or sealing of the lead? On the plus side our floor was poured yesterday. All the drips coming through the roof are actually not so bad now, as having to hose the slab down a few times a day anyway!

Slab poured today, praise be, and the pressure in the UFH pipes has been going off the scale - as in the needle on the gauge is right round and touching the zero-stop. I have relieved a bit of the pressure and brought it down to 5 bar, but wondering if that's the right thing to do?

Thanks @saveasteading . I guess however mane holes there are, filled or otherwise, in the composite panels, shouldn't matter - as we have the (supposedly) watertight layer of membrane above and then of course the final roofing sheets. I just had a word with the builder on the phone to make sure he was planning on coming over tomorrow morning, which he is. I fired an opening salvo re the faults with the roof, to be met with "it's breathable membrane, of course it's going to leak". So, if possible, I need a dose of reality before my face to face with him tomorrow. So far I can see the problems with the work as follows: - membrane pulled too tight allowing water to pool at the battens - multiple holes all over the membrane (one you can get your hand through) - membrane not lapped over in to lead valley gutters as the leadwork is too proud - galvanised nails used on the lead, not copper - lead gully not stepped (tbh why should it rely on £4 of mastic "leadmate" to keep it watertight when there is the best part of £1k of lead there?) I've just added it up and we've paid just over 7k for this work so far - and that's just for the labour. What should I realistically be execting from him? Redo? Not sure I want him to considering the standard of his work so far. If he can't/doesn't want to, do I find someone else and give him the bill? If he reiterates the "it's breather membrane, of course it's going to leak" what is the best response? I'm so effing hacked off with this. We had to pause the build for the best part of a year while this bloke gave us the runaround as we thought he would do a good job - local recommendations etc.

The fixings in question are 230mm long tech screws - going through the 2" counterbatten, through the 150mm composite panel and in to the z purlin. So essentially you need to aim it right when screwing through from the top, or you will miss the z-purlin, and on a few occasions you hit the steel rafter instead and the self-drilling tip just melts - either way you can be left with a hole. I guess these were not considered a problem at the time as the panels are not meant to be forming the watertight layer, this should be the membrane and final covering - the corrugated sheets. Can I ask what you mean by the depth?

Thanks both. There are counterbattens, as per previous post there are 2x2 battens running vertically down the roof, then membrane, then battens going across. I agree that the membrane does seem to be pulled very tight which holds it against the underside of the battens. @Gus Potter can you explain what you mean by the valley material being "on top"? The lead here sits on 8x1 boards which themselves sit on the 2x2 counterbattens, so the lead is above the level of the membrane.

Thanks all for your replies everyone, sorry its taken a while to reply. In asnwer to a few questions, it's definitely leaking rather than condensation @Jenki. Quite a few areas where its dripping down the walls from under the membrane, but because the membrane is nailed under battens there is no way I can peek under to see where. The lead in the gully goes up about 200mm both sides I think. There is a fall on it, but not sure how much (2%?) and the run of approx 10m is in about 10+ pieces, apparently with "lead mate" between the sheets where they are lapped. @makie is this done correctly? I already had the guy redo it once as the fall was so shallow there was water pooling up and over the laps. Likewise in what way has the valley not been felted properly? @saveasteading - the panels should't leak, but they are screwed down to z-purlins (and the 2x2 timbers on them the same) and in a few areas where the screw didn't take or whatever there are holes going through with no screw, if that makes sense. So essentially can't rely on the panels as a watertight layer unfortunately. There are quite a few tears in the membrane all over tbh. Quantity is a bucket or so. @ToughButterCup, cold beer time. So, to rectify this, could I just put another layer of felt OVER the battens? The final covering is currugated sheets, so even with membrane over the batten there will be air flow between this and the sheet. Trouble is, if I get it all stripped off, there's no guarantee the second time it gets done will be any better....

Not possible unfortunately, our roof is composite panels, 2x2 timbers running down this and felted over that. I can see lots of drips running down the panels under the felt, but no idea where the water is getting in.