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UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions. |
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#1
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Flat roof question.
Recent rain has shown my flat roof is leaking. It's part of a conversion
built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. -- *I tried to catch some fog, but I mist.* Dave Plowman London SW To e-mail, change noise into sound. |
#2
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Flat roof question.
On 26/07/2020 13:35:58, Dave Plowman (News) wrote:
Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. EPDM seem all the rage. https://en.wikipedia.org/wiki/Flat_roof#EPDM |
#3
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Flat roof question.
"Dave Plowman (News)" Wrote in message:
Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. See what the little men say.... -- Jimk ----Android NewsGroup Reader---- http://usenet.sinaapp.com/ |
#4
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Flat roof question.
In article ,
Jethro_uk wrote: On Sun, 26 Jul 2020 13:35:58 +0100, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. I find it mildly curious that in the 21st century, no one has seen fit to come up with something that can be poured, finds the crack and seals it ... It's already had that treatment. But same as paint, doesn't last forever. -- *The colder the X-ray table, the more of your body is required on it * Dave Plowman London SW To e-mail, change noise into sound. |
#5
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Flat roof question.
On Sun, 26 Jul 2020 14:07:41 +0100, Fredxx wrote:
EPDM seem all the rage. https://en.wikipedia.org/wiki/Flat_roof#EPDM Had ours fibre glassed about 10 years ago. New OSB boards, the old torch-on felt had failed and knackered those boards. Took the oportunity to fit 100 mm of celotext between the roof joists. The fibre glass is still waterproof or at least if it is leaking it's not getting to anywhere visible inside. But then there is a poly sheet on the warm side of the insulation and up and over the joists... -- Cheers Dave. |
#6
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Flat roof question.
On Sun, 26 Jul 2020 13:35:58 +0100, "Dave Plowman (News)"
wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. Here you go, Dave. Don't say I never do anything for you: https://polyroof.co.uk/ |
#7
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Flat roof question.
In article l.net,
Dave Liquorice wrote: On Sun, 26 Jul 2020 14:07:41 +0100, Fredxx wrote: EPDM seem all the rage. https://en.wikipedia.org/wiki/Flat_roof#EPDM Had ours fibre glassed about 10 years ago. New OSB boards, the old torch-on felt had failed and knackered those boards. Took the oportunity to fit 100 mm of celotext between the roof joists. The fibre glass is still waterproof or at least if it is leaking it's not getting to anywhere visible inside. But then there is a poly sheet on the warm side of the insulation and up and over the joists... Big snag is actually knowing how long these 'new' methods do last. Plenty claims, though. The decking is marine ply, so hoping it will still be just fine. The chippie who did the work was very good indeed. -- *If we weren't meant to eat animals, why are they made of meat? Dave Plowman London SW To e-mail, change noise into sound. |
#8
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Flat roof question.
On 26/07/2020 13:35, Dave Plowman (News) wrote:
Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. Glassfibe will be quite a bit more expensive than EPDM. Probably best to find a roofer who can provide quotes. I don't think any special tools are needed to install EPDM, so it may be suitable for DIY, though you may need several people to handle the weight. It took 1 day to reroof a double garage with EPDM including changing some boarding and maybe a joinst. -- Michael Chare |
#9
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Flat roof question.
On 26/07/2020 13:35, Dave Plowman (News) wrote:
Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. How about old fashioned lead ? |
#10
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Flat roof question.
In article ,
Dave Plowman (News) wrote: In article l.net, Dave Liquorice wrote: On Sun, 26 Jul 2020 14:07:41 +0100, Fredxx wrote: EPDM seem all the rage. https://en.wikipedia.org/wiki/Flat_roof#EPDM Had ours fibre glassed about 10 years ago. New OSB boards, the old torch-on felt had failed and knackered those boards. Took the oportunity to fit 100 mm of celotext between the roof joists. The fibre glass is still waterproof or at least if it is leaking it's not getting to anywhere visible inside. But then there is a poly sheet on the warm side of the insulation and up and over the joists... Big snag is actually knowing how long these 'new' methods do last. Sounds like the story of the salesman who turned up at Steinway pianos saying "We've got this wonderful new material for piano hammers instead of that old fashioned felt." Steinway said they try it out. "Ah, when should I come back?" "In about 100 years." -- from KT24 in Surrey, England "I'd rather die of exhaustion than die of boredom" Thomas Carlyle |
#11
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Flat roof question.
In article ,
Robert wrote: On 26/07/2020 13:35, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. How about old fashioned lead ? Doesn't help indoor FM radio reception. -- from KT24 in Surrey, England "I'd rather die of exhaustion than die of boredom" Thomas Carlyle |
#12
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Flat roof question.
Robert Wrote in message:
On 26/07/2020 13:35, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. How about old fashioned lead ? It is SW londun after all..... -- Jimk ----Android NewsGroup Reader---- http://usenet.sinaapp.com/ |
#13
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Flat roof question.
On 26/07/2020 19:18, charles wrote:
In article , Dave Plowman (News) wrote: In article l.net, Dave Liquorice wrote: On Sun, 26 Jul 2020 14:07:41 +0100, Fredxx wrote: EPDM seem all the rage. https://en.wikipedia.org/wiki/Flat_roof#EPDM Had ours fibre glassed about 10 years ago. New OSB boards, the old torch-on felt had failed and knackered those boards. Took the oportunity to fit 100 mm of celotext between the roof joists. The fibre glass is still waterproof or at least if it is leaking it's not getting to anywhere visible inside. But then there is a poly sheet on the warm side of the insulation and up and over the joists... Big snag is actually knowing how long these 'new' methods do last. Sounds like the story of the salesman who turned up at Steinway pianos saying "We've got this wonderful new material for piano hammers instead of that old fashioned felt." Steinway said they try it out. "Ah, when should I come back?" "In about 100 years." Sometime in the 1970s I was involved in a submarine cable project. Featuring Germanium transistors "Silicon hasn't been around long enough to know they will last" Asked my oncologist "what is the 15 years outlook for this chemotherapy?" "Dunno: it's only been around just over a decade" -- "What do you think about Gay Marriage?" "I don't." "Don't what?" "Think about Gay Marriage." |
#14
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Flat roof question.
On Sunday, 26 July 2020 13:36:08 UTC+1, Dave Plowman (News) wrote:
Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. EPDM & fibreglass are both diyable. The issue we ran into with EPDM is that it's not compatible with bitumen, so every bit of boarding must be stripped off & renewed. Lead is a foolish idea these days, even in apparently inaccessible places. Copper even more so. Many swear by steel, but it gets ugly in time. In the end we left the old felt in place & used bedsheet, bitumen & sand. Crude for sure, but it was a very quick job costing almost £20 something and last time I looked was still in good nick years later. If/when it deteriorates, more cloth & bitumen is only another £20. NT |
#15
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Flat roof question.
wrote in message ... On Sunday, 26 July 2020 13:36:08 UTC+1, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. EPDM & fibreglass are both diyable. The issue we ran into with EPDM is that it's not compatible with bitumen, so every bit of boarding must be stripped off & renewed. Lead is a foolish idea these days, even in apparently inaccessible places. Copper even more so. Many swear by steel, but it gets ugly in time. Not when heavily galvanised it doesnt. And neither does aluminium. In the end we left the old felt in place & used bedsheet, bitumen & sand. Crude for sure, but it was a very quick job costing almost £20 something and last time I looked was still in good nick years later. If/when it deteriorates, more cloth & bitumen is only another £20. NT |
#16
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"Who or What is Rod Speed?"
"Who or What is Rod Speed?
Rod Speed is an entirely modern phenomenon. Essentially, Rod Speed is an insecure and worthless individual who has discovered he can enhance his own self-esteem in his own eyes by playing "the big, hard man" on the InterNet." https://www.pcreview.co.uk/threads/r...d-faq.2973853/ -- Senile Rodent about himself: "I was involved in the design of a computer OS" MID: |
#17
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Flat roof question.
I've been using EDPM,
went on a one day course to learn how to do the corners. https://www.permaroof.co.uk/rubber-roof-videos It's easy to repair with its special primer and glues and patches, like when i dropped a slate on it. Made by firestone , Ultra violet resistant. Normal shed roofing only lasts a few years. Lead has to have gaps for expansion where nwater dirt and ice get in. And while youre at it add loads of insulation under it. I did OSB3, then kingspan attached with foam, then OSB3, then EDPM George On Sunday, July 26, 2020 at 1:36:08 PM UTC+1, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. -- *I tried to catch some fog, but I mist.* Dave Plowman London SW To e-mail, change noise into sound. |
#18
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Flat roof question.
George Miles wrote:
I've been using EDPM, Did my garage/kitchen/porch about 12 years ago. I did OSB3, then kingspan attached with foam, then OSB3, then EDPM Why two decks? |
#19
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Flat roof question.
On Monday, July 27, 2020 at 10:17:00 AM UTC+1, Andy Burns wrote:
George Miles wrote: I've been using EDPM, Did my garage/kitchen/porch about 12 years ago. I did OSB3, then kingspan attached with foam, then OSB3, then EDPM Why two decks? First OSB3 was 18mm for the structure, on top of beams. Then a 2 layers of kingspan attached with foam then thinnner osb3 foamed on it (no screws or cold bridging, and makes roof walkable) then glued EDPM onto it. [g] |
#20
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Flat roof question.
On 27/07/2020 10:04, George Miles wrote:
I've been using EDPM, went on a one day course to learn how to do the corners. https://www.permaroof.co.uk/rubber-roof-videos It's easy to repair with its special primer and glues and patches, like when i dropped a slate on it. Made by firestone , Ultra violet resistant. I am glad that it is easy to repair as it looks like it might be easily damaged. -- Michael Chare |
#21
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Flat roof question.
In article ,
Robert wrote: On 26/07/2020 13:35, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. How about old fashioned lead ? Care to guess what that would cost? And likely to reinforce the roof which wasn't designed for it? Zinc would be cheaper. But noisy in the rain. -- *Most people have more than the average number of legs* Dave Plowman London SW To e-mail, change noise into sound. |
#22
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Flat roof question.
In article ,
charles wrote: In article , Robert wrote: On 26/07/2020 13:35, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. How about old fashioned lead ? Doesn't help indoor FM radio reception. Some of us have external aerials. ;-) -- *Okay, who stopped the payment on my reality check? * Dave Plowman London SW To e-mail, change noise into sound. |
#23
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Flat roof question.
In article ,
George Miles wrote: I've been using EDPM, went on a one day course to learn how to do the corners. https://www.permaroof.co.uk/rubber-roof-videos It's easy to repair with its special primer and glues and patches, like when i dropped a slate on it. Made by firestone , Ultra violet resistant. Normal shed roofing only lasts a few years. Well, this has lasted 30. So you're not doing a good job of selling an alternative. ;-) -- *When everything's coming your way, you're in the wrong lane * Dave Plowman London SW To e-mail, change noise into sound. |
#24
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Flat roof question.
In article , Dave Plowman (News)
wrote: In article , charles wrote: In article , Robert wrote: On 26/07/2020 13:35, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. How about old fashioned lead ? Doesn't help indoor FM radio reception. Some of us have external aerials. ;-) which would ned to well above the new "earth" -- from KT24 in Surrey, England "I'd rather die of exhaustion than die of boredom" Thomas Carlyle |
#25
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Flat roof question.
On 26/07/2020 13:35, Dave Plowman (News) wrote:
Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. For a flat roof on a double garage the quote was £2100+ vat for EPDM, part of one joist and removal of old material. -- Michael Chare |
#26
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Flat roof question.
On Monday, July 27, 2020 at 12:59:29 PM UTC+1, Michael Chare wrote:
On 27/07/2020 10:04, George Miles wrote: I've been using EDPM, went on a one day course to learn how to do the corners. https://www.permaroof.co.uk/rubber-roof-videos It's easy to repair with its special primer and glues and patches, like when i dropped a slate on it. Made by firestone , Ultra violet resistant. I am glad that it is easy to repair as it looks like it might be easily damaged. -- Michael Chare EDPM stuck to OSB is tough stuff, I broke mine by a slate sliding from high up the roof and spearing it with a point [g] |
#27
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Flat roof question.
On Monday, July 27, 2020 at 4:55:34 PM UTC+1, Michael Chare wrote:
On 26/07/2020 13:35, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance.. For a flat roof on a double garage the quote was £2100+ vat for EPDM, part of one joist and removal of old material. -- Michael Chare Check out the price of a kit from Permaroof if you do it yourself, its not difficult. And because it comes in a single sheet you dont have to do it all in one day, you can drape the sheet over before gluing if it rains, and stick one edge on day, the rest another day. It took me months to do parts of my house roof with it because so many corners [g] [g] |
#28
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Flat roof question.
"Dave Plowman (News)" wrote:
Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. What would the team suggest for a 20 year old felt/bitumen flat roof that has a small leak, but has some degree of sagging which causes ponding - possibly due to movement of the underlying structure rather than softness of the roof itself? I see there's the equivalent of floor levelling compound for flat roofs, but is it any good, especially on top of existing bitumen? How does it manage to achieve a fall, rather than being a horizontal level? Have quotes 2-3K for a strip and redo, but wondering if there's anything less drastic? Thanks Theo |
#29
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Flat roof question.
Theo wrote:
some degree of sagging which causes ponding - possibly due to movement of the underlying structure Can you get any wedges/packers between the top of rafters and the ply/osb/why? |
#30
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Flat roof question.
On Sun, 26 Jul 2020 18:20:35 +0100, Dave Plowman (News) wrote:
Had ours fibre glassed about 10 years ago. Big snag is actually knowing how long these 'new' methods do last. True enough, though glassfibre has been about for quite a number of decades in other things like boats. -- Cheers Dave. |
#31
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Flat roof question.
Andy Burns wrote:
Theo wrote: some degree of sagging which causes ponding - possibly due to movement of the underlying structure Can you get any wedges/packers between the top of rafters and the ply/osb/why? Possibly by taking the ceiling below out, but then I'm not sure that making good the ceiling is going to be much less work than redoing the roof. (There may be asbestos fibres in the ceiling, just for added excitement) Theo |
#32
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Flat roof question.
On 28 Jul 2020 10:33:51 +0100 (BST), Theo
wrote: "Dave Plowman (News)" wrote: Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. What would the team suggest for a 20 year old felt/bitumen flat roof that has a small leak, but has some degree of sagging which causes ponding - possibly due to movement of the underlying structure rather than softness of the roof itself? I see there's the equivalent of floor levelling compound for flat roofs, but is it any good, especially on top of existing bitumen? How does it manage to achieve a fall, rather than being a horizontal level? Have quotes 2-3K for a strip and redo, but wondering if there's anything less drastic? Thanks Theo Just had our garage completely re-roofed. Cost about 900 GBP. That ws after more than 25 years use and the old roof was very badly installed, according to the roofer who stripped it off, whixh id why it blew off. I reckon if you've had 20 years out of it that's not bad and maybe it's time for a completely new one. - Mike |
#33
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Flat roof question.
Mike wrote:
Just had our garage completely re-roofed. Cost about 900 GBP. Interesting. This is also a garage (conversion), let me guess about 6m x 3.5m. That sounds rather cheap! (2-3K quotes did not include removing much woodwork assuming it to be otherwise sound) That ws after more than 25 years use and the old roof was very badly installed, according to the roofer who stripped it off, whixh id why it blew off. I reckon if you've had 20 years out of it that's not bad and maybe it's time for a completely new one. That was the initial assumption. However it doesn't seem to have failed completely, so wondering if there was something that could keep it going for a bit longer (pending other things). Theo |
#34
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Flat roof question.
On 26/07/2020 15:22, Chris Hogg wrote:
On Sun, 26 Jul 2020 13:42:50 -0000 (UTC), Jethro_uk wrote: On Sun, 26 Jul 2020 13:35:58 +0100, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. I find it mildly curious that in the 21st century, no one has seen fit to come up with something that can be poured, finds the crack and seals it ... I have done just that with Isoflex liquid rubber. Leaked at the junction between my and my neighbour's garage roofs, bitumen felted. Must have been quite a big crack as it took quite a lot, and at one point appeared dribbling down the inside of the garage wall. Sealed the leak though. https://tinyurl.com/y2fgfmzo Joints in flat roofs are almost guaranteed to fail, especially if both were originally built-up 3 -layer felt and one half has been replaced with 2-layer torch-on felt. The heat of the sun, and the dryness, especially the weather we have had this year will soon make the joint fail. IS the decking chipboard, plywood or OSB ? The first will not like ingress of water. If you are going to treat flat areas their special primer is well worth using first. I did my garage roof with an EPDM kit, but that involved redecking with OSB3 first. 5.5 mtres by 2.8 metres. It was just on the limit of my ability to get it up the ladder. A 5x5 sheet of epdm will need 2 people. Flat roofs need replacing at least every 20-25 years. Some really bad bodge jobs, like the garage roof of my first house was done in 2-layer felt in 1976, before the days of fibreglass reinforced felt and every house had a leaking garage roof within 10 years. |
#35
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Flat roof question.
On 26/07/2020 16:32, Dave Plowman (News) wrote:
In article , Jethro_uk wrote: On Sun, 26 Jul 2020 13:35:58 +0100, Dave Plowman (News) wrote: Recent rain has shown my flat roof is leaking. It's part of a conversion built about 30 years ago. Very nicely built - the correct lie etc and marine ply decking, and lead flashing. Think it is three layer. Size approx 5x5 metres. Any of the modern alternatives better? Membrane or fibreglass? And a rough idea of relative costs would be nice too. Access is easy, but it's never walked on etc except for any maintenance. I find it mildly curious that in the 21st century, no one has seen fit to come up with something that can be poured, finds the crack and seals it ... It's already had that treatment. But same as paint, doesn't last forever. Isoflex, when used with its special primer should add about 8 years to the life, provided it has no ponding or other problems. |
#36
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Flat roof question.
On 27/07/2020 12:59, Michael Chare wrote:
On 27/07/2020 10:04, George Miles wrote: I've been using EDPM, went on a one day course to learn how to do the corners. https://www.permaroof.co.uk/rubber-roof-videos It's easy to repair with its special primer and glues and patches, like when i dropped a slate on it. Made by firestone , Ultra violet resistant. I am glad that it is easy to repair as it looks like it might be easily damaged. The 1.5 mm stuff is pretty tough. If it never or rarely gets walked on then you would have to be very unlucky to damage it, unless you have an arsewipe as a neighbour who chucks hydraulic oil and or solvents on it. It is glued onto OSB3/plywood using a water-based adhesive that is rolled on with a decorating roller so as well as the EPDM itself you have this layer of adhesive that seeps into the decking and provides a 2nd level of protection. |
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Flat roof question.
On 27/07/2020 14:20, Dave Plowman (News) wrote:
In article , George Miles wrote: I've been using EDPM, went on a one day course to learn how to do the corners. https://www.permaroof.co.uk/rubber-roof-videos It's easy to repair with its special primer and glues and patches, like when i dropped a slate on it. Made by firestone , Ultra violet resistant. Normal shed roofing only lasts a few years. Well, this has lasted 30. So you're not doing a good job of selling an alternative. ;-) You said it had already been treated with something, so the actual original probably lasted 20-25? years which is about right for a built-up felted roof. Unless you want to reseal it with Isoflex or whatever every 5 to 8 years thenyou might as well just get it re-felted. Avoid Acrypol if you have already using Isoflex, the two are not compatible. DTDIGTTS. |
#38
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Flat roof question.
On 28/07/2020 10:54, Theo wrote:
Andy Burns wrote: Theo wrote: some degree of sagging which causes ponding - possibly due to movement of the underlying structure Can you get any wedges/packers between the top of rafters and the ply/osb/why? Possibly by taking the ceiling below out, but then I'm not sure that making good the ceiling is going to be much less work than redoing the roof. (There may be asbestos fibres in the ceiling, just for added excitement) Theo Sounds like it has already leaked allowing the decking to weaken and sag, hence the ponding. Complete re-decking it the solution. Be aware that part L means it will need to be insulated and too many roofing people will insist on adding insulation on top of the decking and then putting the felt over the insulation. If your flat roof is a 'cold roof' (most are) , this is s complete waste of time since the ventilaton will still allow cold air to circulate underneath the insulation. If the roof is redecked then adding 'celotex' between the joists and cut to fit snugly, and the joints taped with silver foil tape with an air gap above it is the way to go. |
#39
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Flat roof question.
On 28/07/2020 14:00, Theo wrote:
Mike wrote: Just had our garage completely re-roofed. Cost about 900 GBP. Interesting. This is also a garage (conversion), let me guess about 6m x 3.5m. That sounds rather cheap! For redecking and felting, the going rate seems to be about £100 per square metre. I did my garage roof myself, 5.5 metres by 2.6 metres and is cost me £700 just for materials, - 6 sheets OSB3 @ £21/sheet 4 new rafters to replace rotten ones UPVC cladding over existing barge boards EPDM kit, with adhesive, guttering and upstand trims Screws and fixings. OSB3 must be screwed not nailed. (2-3K quotes did not include removing much woodwork assuming it to be otherwise sound) That ws after more than 25 years use and the old roof was very badly installed, according to the roofer who stripped it off, whixh id why it blew off. I reckon if you've had 20 years out of it that's not bad and maybe it's time for a completely new one. That was the initial assumption. However it doesn't seem to have failed completely, so wondering if there was something that could keep it going for a bit longer (pending other things). Theo |
#40
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Flat roof question.
Andrew wrote:
Sounds like it has already leaked allowing the decking to weaken and sag, hence the ponding. Complete re-decking it the solution. That's what I suspected. Although I wondered if there was a say 5 year shorter term fix? Be aware that part L means it will need to be insulated and too many roofing people will insist on adding insulation on top of the decking and then putting the felt over the insulation. If your flat roof is a 'cold roof' (most are) , this is s complete waste of time since the ventilaton will still allow cold air to circulate underneath the insulation. This is a semi-integral garage, so I'm not sure part L applies? It's still got a great big garage door, even if the internals are a bit nicer than a normal garage. It isn't heated. Quoters seemed to suggest stripping it back to add insulation would be much more than a simple re-roof. Trying to avoid 'and while you're doing that...' project creep. Theo |
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