junglejim

Thank you that’s helpful. Are you pointing to the groove in the window frame? One theory I have is that it’s getting in through the joint between frame and cill as circles in attached. Adding sealant where you suggest could be a solution.

That looks neat. The cill and frame were fitted together but manufacture details show it as 2 parts. (See attached technical drawings) There’s no upstand though… that’s looks neat but not something on mine.

Yes taped with tescon vana

So… we survived storm Goretti (just!). With torrential rain and driving winds of 90mph+ it was a pretty extreme test of our build. Having got through other storms and downpours unscathed I was uncharacteristically optimistic but… frustratingly 3 or our windows have some water ingress at the bottom corner. The windows are Prestige Sheerline. The cills overhang the cladding well and underneath is dry but the wind has blown hard pushing water into the lower right hand corner. I think my cladding reveal had been too tight to the cill and trapped water as seems quite waterlogged but… around the window I used compriband expandable tape and Tescon vana so should be well sealed. I’m a bit stumped how the water has got in but one possibility is through the end caps of the cill… (edit: on second look I don’t think that’s possible as the cill ends extend beyond the opening.) one other possibility is that the water is being blown into the drainage area and sloping to the ends… according to prestige this should be sealed with silicone (see attached) and I can see some silicone but there’s no way of telling if it’s failed. I’ve added some manufactures pics but thinking it’s likely to be something I’ve done rather than manufactured but there was a lot of debris blown and washed into the end if the drainage area highlighted on one of the drawings so a lot of water has been pushed this way. i realise that 90mph and torrential rain is extreme but I’m off the opinion that water shouldn’t be able to get in and would like not to have to worry about this in future. The attached image is from ‘clevett’ video (not mine) but similar to my finished result. Any tips/suggestions etc greatly appreciated. The stress of self building is definitely showing in my hair colour!!

Really useful post. Thank you. Any chance you can share a close up of the detailing at the bottom corner of your windows externally where there will be cladding…. Just had a set back on our build… thought we were watertight but 90mph winds and torrential rain means water had found its way in at the bottom corner of windows. I thought I’d sealed/an everything well but think I had the cladding too tight to the cill so water couldn’t drain underneath. Still unsure what route it’s taken behind but interested to see how others detail this. also… did you cut out studs in doorways? I have a sole plate with stud base plate ontop so essentially double sole plate internally. I’d like to cut out the top one in doorways so that I can run insulation and ufh and screed through easily. Thank you

Thanks that’s helpful. Hoping I can switch the apron out without taking out all of the tiles around the window. Keeping fingers crossed that just the lower ones will be ok. struggling to bend the edt back into position so may need to replace those too but would rather not if possible so any suggestions would be welcome. Also wondering if there’s any way to improve the overlap at the edges. moving the tiles across the whole roof isn’t an option but maybe some kind of metal strap screwed into the batten and extending over the apron. Thank you for all the advice. Racking my brain here trying to figure out solutions so any experience/advice very welcome 👍

Advice from VELUX is that I need more overlap with tiles at the ends to hold it down. With these interlocking tiles (Sandtoft new rivius antique) and the wide gauge in not sure how to achieve this or whether there is any kind of workaround. Any advice greatly appreciated. Thank you

All of our velux aprons have damaged in the storm. One has sheared off completely (the malleable type for tiles EDW). We have some others that are flat which I thought would be better but are bent upwards and won’t reshape into position. Any ideas and best way to fix and long term solutions? ta

Thanks… that was my gut feeling. Do you think good above both?

Thanks for the reply. This is an internal stud wall on timber frame build. Raft slab. No dpm under the slab. Will lap up external walls but no bed on internal stud as within the envelope but had wondered about taping to the dpm strip under the stud. Have read that overlap alone is sufficient though hence confusion. ta

Argh I’m overthinking this so could do with some advice. Here’s a photo of my internal stud wall with dpm strips underneath. I was going to lift up the thicker black dpm and lay my floor dpm with double sided tape between the 2 but thinking now that it’s probably better to lay the floor dpm over both? I’m also unsure whether taping is needed or the overlap is sufficient? Paused mid job to think over a brew so any advice greatly appreciated. 👍☕️ @nod@Nickfromwales @saveasteading

Thanks for all the advice so far. One more detail I’m wondering is how high to bring the floor rpm up the stud work? It would seem to make sense on the external walls to lap up the concrete upstand (overlapping soleplate dpm) and then tape to the soleplate or sills or be left open at the edges and come up higher? or… extend the dpm higher to underlap ybs foil and then tape the joint between ybs and dpm

Currently building a new house and looking at my electrical planning. I’ve read somewhere that DC is worth considering as an alternative to traditional ac lighting circuits. Wondering if anyone has any advice or opinions one way or the other. Ideally looking to future proof and also with sustainability in mind.

happy Christmas. thanks for all the advice. There’s none underneath. It’s a raft slab.

Difficult to explain but here’s what I’m thinking. The difference from what seems to be the norm is not taking the perimeter strip all the way to the concrete slab. It feels better to make sure the insulation is tight/snug to the edges of the room. Unless the perimeter strip (green) is supposed to also provide some compression/expansion around the pir.

Thank you Nick for such a thorough response. That’s as I imagined. I’ll definitely be using the foam strip as advised by the screed company but think it’ll be better above the insulation rather than all the way to slab. These also suggested osb strips at the bottom of the studs to give the strip a solid backing to adhere to… makes sense although possibly belt and braces. Any further advice welcome 👍

Thanks… that’s an interesting point… was planning on taping it to the insulation and also to the stud

Thanks. The polythene is a skirt on the expansion strip to be taped to visqueen layer laid ontop of insulation. I’m really questioning the logic of running the expansion strip full depth rather than above the insulation… seems like standard practice to go full depth so I’m wondering if there’s something that I’m not understanding.

Thanks for the advice. The image I first posted was from Google and not exactly illustrative of my case (timber frame). I realise the external wall will need additional insulation such as 25mm perimeter pir up to ffl I think. My main question is around the use of the expansion strip. I’ve attached an image that our screed company has provided as an example of what to do. However my instinct is to run the pir right to the stud then install the expansion strip above. Unless it’s serving another purpose?

I’m a bit confused by what seems to be standard practice so must be missing something…. The advice is to fix the expansion strip to the perimeter prior to floor insulation. (See attached) Surely as this is much less insulating than pir it provides a potential cold route to the slab around the edge of every room? Would it not be better to fit the insulation tight to the edges and then add the expansion strip above this. Taping the ‘skirt’ to the top of the insulation / visqueen layer will ensure a good seal for the screed without the need to compromise on floor insulation? i also thought it was good practice to install a vertical strip of pir around the edges but does the expansion strip negate the need for this? I’m likely missing something so any advice greatly appreciated. Thank you

I’m just trying to work out the detail for pir insulation with ufh and screed at external door junctions. Along the exterior walls I think I need a vertical strip (25mm wide) of pir that will finish flush to the finished screed level and be hidden by the flooring and skirting. However where there are door junctions this will be against the bottom of the frame and the engineered floor will go over the top. In wondering if as it’s a high traffic area I should really use something like brigi foam at these junctions or am I over thinking it? Thanks for any help

Thank you for the thorough reply. The black dpm where your arrow is folds down and underlaps the dpm beneath stud partition by about 150mm. There isn’t any tape though but not sure if that’s essential? You’re correct to notice that the black dpm underneath the studs doesn’t extend 100mm … more like 50mm but the clear strip which also goes under the partition extends about 200mm. I’m hoping that’s ok and I can then tape the membrane that I’m laying over the concrete floor onto this. Thank you again, really appreciate any further advice you have here.

Top of screed will be just above no.2

Thanks for your reply Mike. Sorry I’m not explaining clearly. My issue (I think) is that I can’t access the small sections where the partition wall butts against the perimeter upstand/soleplate. The issue is 2 fold; 1. I can’t bend the dpm that is under the soleplate upwards as it’s folded down between the partition. This may not be an issue but 2. I can’t get in between the partition junction to seal the laps. there is no exposed concrete as the dpm strips overlap but they aren’t taped or sealed between partition and upstand. in my mind it would have been better to lay the dpm across the whole slab before the partition walls but this was done by the TF installer as standard.

Just resurrecting this in the hope someone can advise on my first point? Ta