- Joined
- 5 Jan 2016
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hi guys
we got our groundwork/drainage passed this weekend so iv been looking at the roof, i know how do you go from ground to roof? im always looking wayyyy ahead.
im miffed by the drawing my architect has come up with for my extension. We have plans for a flat roof with EPDM covering and a 1x1.5M roof lantern. there's a few issues i have picked out and i have questioned some of them already.
i have attached a couple of snap shots of the building regs.
i cannot see how you would get cross ventilation from either side with the lantern in place. the lantern cutout/framing would be blocking the crossflow.
jump to drawing 2 picture. roof consists of 150mm timers, with 50mm timers going in the oposite direction with superfoil sandwiched between. 50mm airgap abouve superfoil achieved by the 50mm battens. so if im right, its this 50mm space that neds venting as that is where main difference in moists and temperature changes are going to be.
soffit side venting would work up to the poiunt where the skylight comes out, then it would block direction from either side?
we couldnt get a warm roof design due to our houses having slightly higher cielings and the whole permitted development sizes. i wish we went full PP and just went with a taller roof!
there's a couple other defects but maybe i am missing something
Details2 picture says joists to be 150mm in depth.
Details1 says 200 x 50 C16 @ 400ctrs
flitch beam is a195x50 c16, with an odd sized flitch plate of 170mm?
it looks like it's computer calculated sizes, and nothings been matched up to equal beam sizes? so 195 would be rounded to 200?? 50mm would be 47mm?
U beam with 8mm plate, IMO 10mm would be better in terms of jointing depth
flat roof isnt really a flat roof, there's usually a run off?
we got our groundwork/drainage passed this weekend so iv been looking at the roof, i know how do you go from ground to roof? im always looking wayyyy ahead.
im miffed by the drawing my architect has come up with for my extension. We have plans for a flat roof with EPDM covering and a 1x1.5M roof lantern. there's a few issues i have picked out and i have questioned some of them already.
i have attached a couple of snap shots of the building regs.
i cannot see how you would get cross ventilation from either side with the lantern in place. the lantern cutout/framing would be blocking the crossflow.
jump to drawing 2 picture. roof consists of 150mm timers, with 50mm timers going in the oposite direction with superfoil sandwiched between. 50mm airgap abouve superfoil achieved by the 50mm battens. so if im right, its this 50mm space that neds venting as that is where main difference in moists and temperature changes are going to be.
soffit side venting would work up to the poiunt where the skylight comes out, then it would block direction from either side?
we couldnt get a warm roof design due to our houses having slightly higher cielings and the whole permitted development sizes. i wish we went full PP and just went with a taller roof!
there's a couple other defects but maybe i am missing something
Details2 picture says joists to be 150mm in depth.
Details1 says 200 x 50 C16 @ 400ctrs
flitch beam is a195x50 c16, with an odd sized flitch plate of 170mm?
it looks like it's computer calculated sizes, and nothings been matched up to equal beam sizes? so 195 would be rounded to 200?? 50mm would be 47mm?
U beam with 8mm plate, IMO 10mm would be better in terms of jointing depth
flat roof isnt really a flat roof, there's usually a run off?