Andrew Posted May 30, 2020 Share Posted May 30, 2020 Just trying to get my head around the detailing around the windows for our build. We have timber frame with horizontal Siberian Larch cladding counter battened onto the frame. This is a picture from the internet and looks like a fairly typical detail with wooden reveals around top and sides with a cill at the bottom. But I'm trying to understand what happens at the top with regards to managing moisture. Our windows will be set back into the timber frame, so there will be a fairly deep reveal across the cavity and into the top of the window. I have seen some details with a metal flashing on the top of this top wooden reveal but there are plenty of pictures like the one above without. Also is anything special needed with regards to draining the cavity above the window. Unless I'm missing something there seems a high likelihood of water pooling above the window in the cavity on top of the reveal? Has anyone done this or know how this is normally done? Link to comment Share on other sites More sharing options...
nod Posted May 30, 2020 Share Posted May 30, 2020 12 minutes ago, Andrew said: Just trying to get my head around the detailing around the windows for our build. We have timber frame with horizontal Siberian Larch cladding counter battened onto the frame. This is a picture from the internet and looks like a fairly typical detail with wooden reveals around top and sides with a cill at the bottom. But I'm trying to understand what happens at the top with regards to managing moisture. Our windows will be set back into the timber frame, so there will be a fairly deep reveal across the cavity and into the top of the window. I have seen some details with a metal flashing on the top of this top wooden reveal but there are plenty of pictures like the one above without. Also is anything special needed with regards to draining the cavity above the window. Unless I'm missing something there seems a high likelihood of water pooling above the window in the cavity on top of the reveal? Has anyone done this or know how this is normally done? This is one I did a few weeks ago It was onto block work Batons then membrane Batons on the reveals and head Cladded with Cedar then we used a 50 mil 5 mil thick Cedar angle mitred to dress all the opening Sorry no close up I can take one on Monday if needed Link to comment Share on other sites More sharing options...
ToughButterCup Posted May 31, 2020 Share Posted May 31, 2020 9 hours ago, nod said: ... It was onto block work Batons then membrane Batons on the reveals and head Cladded with Cedar then we used a 50 mil 5 mil thick Cedar angle mitred to dress all the opening Sorry no close up I can take one on Monday if needed Gary, I'd be so glad if you would please. I'm working on the same issue.... Thanks Link to comment Share on other sites More sharing options...
nod Posted May 31, 2020 Share Posted May 31, 2020 15 minutes ago, AnonymousBosch said: Gary, I'd be so glad if you would please. I'm working on the same issue.... Thanks No probs Ian as I stated in a previous post Timber cladding isn’t our bag But with the materials onsite and cladders on Furlough We gave up four days to help out I need to call on there so I’ll snap a couple of photos Link to comment Share on other sites More sharing options...
Gone West Posted May 31, 2020 Share Posted May 31, 2020 11 hours ago, Andrew said: This is a picture from the internet and looks like a fairly typical detail with wooden reveals around top and sides with a cill at the bottom. I'm not sure that the picture is correct in showing how it should be done. It's important that water doesn't collect on the top reveal. On my house I had the top part of the reveal inset from the side pieces so the cladding goes over the top of the front edge of the top reveal with a 3mm weep gap between the cladding and top reveal. 1 1 Link to comment Share on other sites More sharing options...
Andrew Posted May 31, 2020 Author Share Posted May 31, 2020 6 hours ago, nod said: I need to call on there so I’ll snap a couple of photos I’d be really grateful for this too, thanks. Link to comment Share on other sites More sharing options...
Andrew Posted May 31, 2020 Author Share Posted May 31, 2020 4 hours ago, PeterStarck said: On my house I had the top part of the reveal inset from the side pieces so the cladding goes over the top of the front edge of the top reveal with a 3mm weep gap between the cladding and top reveal. Thanks, that detail make a lot of sense. You do see quite a few pictures with all the reveals protruding out from the cladding slightly which looks good but I don’t know how they prevent water build up on top of the top reveal. Do you have a more straight on photo of the window? Link to comment Share on other sites More sharing options...
jamieled Posted May 31, 2020 Share Posted May 31, 2020 I will add to the mix, though we have vertical board on board cladding. I ripped a bit of larch approximately 50mm wide and fixed that over the top of the aluminium window frame. The top edge of this ripped bit of larch is bevelled at about 15 degrees to allow any water behind the cladding out. The cladding then comes down so the bottom bevelled edge of the vertical cladding is in line with the bevelled edge of the piece ripped for the reveal. There is about a 4mm gap then for water to drain out the cavity, with any water running down the vertical larch dropping off on to the aluminium cill of the window. 1 Link to comment Share on other sites More sharing options...
Gone West Posted May 31, 2020 Share Posted May 31, 2020 2 hours ago, Andrew said: Do you have a more straight on photo of the window? Don't know if these help. Link to comment Share on other sites More sharing options...
Andrew Posted May 31, 2020 Author Share Posted May 31, 2020 5 hours ago, jamieled said: I will add to the mix, though we have vertical board on board cladding. I ripped a bit of larch approximately 50mm wide and fixed that over the top of the aluminium window frame. The top edge of this ripped bit of larch is bevelled at about 15 degrees to allow any water behind the cladding out. The cladding then comes down so the bottom bevelled edge of the vertical cladding is in line with the bevelled edge of the piece ripped for the reveal. There is about a 4mm gap then for water to drain out the cavity, with any water running down the vertical larch dropping off on to the aluminium cill of the window. That's really helpful, thanks for posting. Link to comment Share on other sites More sharing options...
Andrew Posted May 31, 2020 Author Share Posted May 31, 2020 3 hours ago, PeterStarck said: Don't know if these help. Thanks, that looks spot on. I'd be really happy if ours ends up looking as sharp. Link to comment Share on other sites More sharing options...
Cpd Posted May 31, 2020 Share Posted May 31, 2020 When I was recently doing some repairs to my cabin windows I realised that water was blowing into the structure between the cladding and the window linings and has caused rot to the fairly cheep marine ply linings (it’s only a cabin...) to solve this I replaced the linings with yet more cheep ply ? (as i had it on stock) but added A rubber seal between The cladding ends and the linings. It’s worked really well and I can at least rest assured that water won’t be getting behind there anymore. The top of the window is ply lined that comes down at an angle So any water will always want to come out, I upgraded this by cutting up some old velux flashings (I have many....) And put them on top with a lip to keep the ply nice and dry. Other photos are of the back of the cabin with the cladding overshooting to protect the linings, The linings are all angled down so that any water that blows in it will always fall towards the cladding rather than the window. The cladding is all cut at 45 degrees to help shed water rather than it sitting on the bottom edge of the boards. 1 Link to comment Share on other sites More sharing options...
Moonshine Posted November 7, 2022 Share Posted November 7, 2022 (edited) i am bringing this thread back as i am also on the hunt of what to do at the head of an opening, and want to get something like these. any idea where they can be sourced from? edit: found this which would work pretty well, but £90 delivery!!!! https://www.steelroofsheets.co.uk/products/over-window-drip/ Edited November 7, 2022 by Moonshine Link to comment Share on other sites More sharing options...
Moonshine Posted November 8, 2022 Share Posted November 8, 2022 Also thinking about detailing to trims, the horizontal cladding is currrntly butted up to the trim, without a gap, though there is advice that a 8mm gap should be left to the trim to "Cladding should be cut to ensure a minimum 8mm gap before vertical members of windows, doors, corner trims or similar. This allows airflow to the end of the boards which aids drying and helps prevent excessive moisture uptake.." Anyone done this? Link to comment Share on other sites More sharing options...
Moonshine Posted November 8, 2022 Share Posted November 8, 2022 I.e finish like the rows at the bottom, or have a gap as per the top row Link to comment Share on other sites More sharing options...
Bonner Posted November 8, 2022 Share Posted November 8, 2022 21 hours ago, Moonshine said: i am bringing this thread back as i am also on the hunt of what to do at the head of an opening, and want to get something like these. any idea where they can be sourced from? edit: found this which would work pretty well, but £90 delivery!!!! https://www.steelroofsheets.co.uk/products/over-window-drip/ What about this? https://www.pvccladding.com/aluminium-drip-profile-3mtr-anthracite-grey-p-XT-DWFP-AG/ 1 Link to comment Share on other sites More sharing options...
Bonner Posted November 8, 2022 Share Posted November 8, 2022 2 minutes ago, Moonshine said: I.e finish like the rows at the bottom, or have a gap as per the top row Not done that, just leave a gap at the bottom where it meets a cill Link to comment Share on other sites More sharing options...
Roundtuit Posted November 8, 2022 Share Posted November 8, 2022 1 hour ago, Moonshine said: "Cladding should be cut to ensure a minimum 8mm gap before vertical members of windows, doors, corner trims or similar. This allows airflow to the end of the boards which aids drying and helps prevent excessive moisture uptake.." Anyone done this? Yes. I'd definitely do it to stop moisture getting trapped. I thought 8mm looked too much, so compromised with 5mm. Link to comment Share on other sites More sharing options...
Moonshine Posted November 8, 2022 Share Posted November 8, 2022 1 hour ago, Roundtuit said: Yes. I'd definitely do it to stop moisture getting trapped. I thought 8mm looked too much, so compromised with 5mm. i did exactly the same thing, i measured out 8mm and it looked too big so wound it in to 5mm as shown the photo. even though its Siberian larch i am going to put wood preserver on the cut ends @Roundtuithave you got any pictures of yours? Link to comment Share on other sites More sharing options...
Moonshine Posted November 8, 2022 Share Posted November 8, 2022 i have been finding this useful https://www.robbins.co.uk/wp-content/uploads/2021/02/TTF-Cladding-Handbook.pdf There is a TRADA External Timber Cladding manual, but i can't find a copy on line without payment 1 Link to comment Share on other sites More sharing options...
Roundtuit Posted November 8, 2022 Share Posted November 8, 2022 Siberian larch treated with Sioo-X sprayed and brushed in. There's a couple of details I'd do differently if doing it again. I've used lead flashing over the top of the windows, lapped up onder the cladding; a proper aluminium pressing would be better, like the ones you linked to. I did the cladding a couple of years before I got round to fitting cills, so fitted the cills between the cladding reveals. I should really have taken the reveals off and fitted over the top of the cill. 1 Link to comment Share on other sites More sharing options...
Moonshine Posted November 12, 2022 Share Posted November 12, 2022 Heres how mine turned out, pretty happy for DIY, need to sort out the head once the drip trays arrive (e g remove the timber batten) Link to comment Share on other sites More sharing options...
Moonshine Posted November 19, 2022 Share Posted November 19, 2022 Got the trim yesterday (£16 for a 3m length collected) all done. Very happy with how it turned out 1 Link to comment Share on other sites More sharing options...
Nick Laslett Posted November 19, 2022 Share Posted November 19, 2022 3 hours ago, Moonshine said: Got the trim yesterday (£16 for a 3m length collected) all done. Very happy with how it turned out Do you have a link for the product you used? Is it the https://www.steelroofsheets.co.uk/products/over-window-drip/ from your earlier post? Link to comment Share on other sites More sharing options...
Moonshine Posted November 19, 2022 Share Posted November 19, 2022 49 minutes ago, Nick Laslett said: Do you have a link for the product you used? Is it the https://www.steelroofsheets.co.uk/products/over-window-drip/ from your earlier post? Its a bespoke bit of metal, that I got cladco to make up. I was working in okehampton on Friday so i could pick up, i ordered it the week before. I provided them with the cad drawing of the size / angle I wanted and they made it up. Not bad for 16 quid. 1 Link to comment Share on other sites More sharing options...
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