Tue, 09 Jun 2026 11:07:44 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56057#Comment_56057 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56057#Comment_56057 Tue, 16 Jun 2009 20:54:41 +0100 jemhayward
Is there an obvious tried and tested solution?

I'm thinking of:
1. lifting the bottom edge of the lowest row of slates by 50mm and inserting spacers on each rafter.
2. some form of forced ventilation system (will building regs buy that?)
3. ventilation from one gable, along the top of the wall (can't really see that working for the far end 9m away)

help! I wasn't expecting this and can't afford to re-roof.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56059#Comment_56059 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56059#Comment_56059 Tue, 16 Jun 2009 21:25:37 +0100 Davipon https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56061#Comment_56061 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56061#Comment_56061 Tue, 16 Jun 2009 21:38:27 +0100 ali.gill http://books.google.co.uk/books?id=XVFyWYdRsZMC&pg=PA128&lpg=PA128&dq=rafter+sprocket&source=bl&ots=lZbuA8pnpe&sig=_aIy4xhG8iNR2YFpeDDWqdtJUPs&hl=en&ei=_AA4Su97w4uMB9aXzP4N&sa=X&oi=book_result&ct=result&resnum=2#PPA128,M1

if that doesnt work just type rafter sprocket into google
also
Rytons OFV1000]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56064#Comment_56064 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56064#Comment_56064 Tue, 16 Jun 2009 22:07:10 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56067#Comment_56067 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56067#Comment_56067 Wed, 17 Jun 2009 00:17:35 +0100 sinnerboy
this cataelouge will most likely give you a solution - possible the FV250 vent

http://www.glidevale.com/downloads/Roof%20Ventilation.pdf]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56068#Comment_56068 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56068#Comment_56068 Wed, 17 Jun 2009 07:47:59 +0100 Nick Parsons https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56070#Comment_56070 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56070#Comment_56070 Wed, 17 Jun 2009 09:10:41 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56082#Comment_56082 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56082#Comment_56082 Wed, 17 Jun 2009 12:01:07 +0100 Davipon https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56107#Comment_56107 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56107#Comment_56107 Wed, 17 Jun 2009 19:31:37 +0100 ali.gill the 50mm vent gap is basically 25mm for the roofing membrane to sag between rafters allowing rivulets to form away from the timber and the membranes fixing punctures; then 25mm ventilation gap between membrane and insulation.
the eaves detail is called clipped or flush eaves.
take a look at the diagram fig.91 in this.
looks feasible to just fix a dummy fascia as a spacer then the actual fascia over the face, so long as your tiles end up projecting over the gutter enough. or alternatively rebate a vent void into the fascia timber.
either way there should be some form of continuous grille at the void. (with specific vent opening dimensions)

http://www.vencel.co.uk/assets/pdf/16.pdf]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56136#Comment_56136 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56136#Comment_56136 Wed, 17 Jun 2009 23:16:59 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56140#Comment_56140 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56140#Comment_56140 Thu, 18 Jun 2009 00:07:31 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56141#Comment_56141 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56141#Comment_56141 Thu, 18 Jun 2009 00:12:44 +0100 ali.gill continuity of insulation
condensation on underside of felt
possible timber decay
listed building restrictions

looks like you need a building control officer with an understanding of historical structures to visit.
sprockets on the rafters would work but raise other issues through altering the plane of the roof tiles - eg susceptibility to wind uplift, driving rain, etc, the effect will depend on location, exposure and existing roof pitch.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56145#Comment_56145 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56145#Comment_56145 Thu, 18 Jun 2009 09:01:50 +0100 jemhayward 1. the roof is shared with adjacent cottages so roofline couldn't be altered
2. pitch is quite shallow (30) so rain could blow up eaves quite well

BCO is reluctant to advise - happy to tell me I'm wrong, but not forthcoming on what is right - for understandable reasons.

I'm warming to the idea of converting to warm roof, just would like to know if its been done this way before.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56154#Comment_56154 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56154#Comment_56154 Thu, 18 Jun 2009 10:47:04 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56194#Comment_56194 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56194#Comment_56194 Thu, 18 Jun 2009 21:59:45 +0100 Davipon http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4078]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56203#Comment_56203 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56203#Comment_56203 Fri, 19 Jun 2009 08:11:14 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56219#Comment_56219 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56219#Comment_56219 Fri, 19 Jun 2009 13:52:13 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56226#Comment_56226 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56226#Comment_56226 Fri, 19 Jun 2009 16:22:51 +0100 mark_s
A row of them near the bottom of the tiles?

Is there existing non-breathable felt?
Could you remove it from the inside - creating a vented space through the slates and fix breatchable membrane to the inside edge of the rafters and your rigid insulation inside this?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56236#Comment_56236 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56236#Comment_56236 Fri, 19 Jun 2009 22:47:33 +0100 Davipon https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56243#Comment_56243 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56243#Comment_56243 Sat, 20 Jun 2009 11:18:01 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56354#Comment_56354 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56354#Comment_56354 Tue, 23 Jun 2009 10:37:27 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56911#Comment_56911 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=56911#Comment_56911 Tue, 30 Jun 2009 13:39:11 +0100 jemhayward https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=70719#Comment_70719 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4163&Focus=70719#Comment_70719 Mon, 04 Jan 2010 16:16:12 +0000 jemhayward