Edpm at edges

[Mr Punter]

Once you have stripped back to the membrane I think you will probably not get too much water ingress.  Then get it PROPERLY designed and detailed - including detail sections through each junction.  Then post the design here for comment.  Then build it to the design.

[Pocster]

4 minutes ago, Mr Punter said:

Once you have stripped back to the membrane I think you will probably not get too much water ingress.  Then get it PROPERLY designed and detailed - including detail sections through each junction.  Then post the design here for comment.  Then build it to the design.

Probably not. But I'm hardly going to risk it.

You saw the quality of their work - better not to rely on it even if there are no leaks.

 

If I follow @PeterW suggestion I'll effectively have 2 rubber layers (1 I don't trust; 1 I do trust) - also saves me removing 35mm concrete. Also solves the load spreading issue with the vehicle ?

Edited October 19, 2018 by pocster

[Pocster]

https://www.wallbarn.com/adjustable-plastic-paving-support-pads/

 

I *guess* it would be best to make the fall on the existing concrete under the new rubber layer . Not sure how to do this .

Next issue would be what it drains to . I guess if a fall can constructed so can a gulley .... just thinking out loud ! ?

[Pocster]

The parking area is the real fly in the ointment!!

[Triassic]

2 hours ago, Triassic said:

Sorry, I'm late to this particular party.

 

Do you have a leak? If so, have you considered using an electronic leak detector? I've used them in the past and they do work!

 

http://www.singleply.co.uk/electronic-leak-detection-for-roofs-advice-for-architects/

It’s well worth trying, it could save you the cost of ripping the original stuff up, When you find the leak it could be repaired, then all you need to do is sort out some of the poor detailing.

Edited October 19, 2018 by Triassic

[Jeremy Harris]

2 minutes ago, Triassic said:

It’s well worth trying, it could save you the cost of ripping the original stuff up, When you find the leak it could be repaired, then all you need to do is sort out some of the poor detailing.

 

 

Looking at the photos of gaps in the EPDM joints, plus the running water tracking across the ceiling from the upstands,  I don't think there's any real doubt as to where the leaks are.

[Pocster]

7 minutes ago, JSHarris said:

 

 

Looking at the photos of gaps in the EPDM joints, plus the running water tracking across the ceiling from the upstands,  I don't think there's any real doubt as to where the leaks are.

But @JSHarris what do you think of my hybrid solution?? ?

[Pocster]

11 minutes ago, Triassic said:

It’s well worth trying, it could save you the cost of ripping the original stuff up, When you find the leak it could be repaired, then all you need to do is sort out some of the poor detailing.

I think I’m well beyond finding the leak !

The particular glass I dug around seems ok visually . Can’t trust ANY of this rubber is best ! 

[Jeremy Harris]

2 minutes ago, pocster said:

But @JSHarris what do you think of my hybrid solution?? ?

 

I think you're in for a lot of work in ripping the existing concrete and pavers off, and, as the problem seems to be entirely a result of bloody awful workmanship by the "roofers" that laid the membrane I can't see any reason why you can't just lay a new layer of EPDM over the roof (after getting back to the existing EPDM), with proper detailing around the upstands and edges.  This roof can be made to work OK, it just needs good workmanship.  The chances are that the existing EPDM can just be trimmed back around the upstands and a new layer laid directly on top of it, I think.

 

Heck of a lot of work, but with luck the concrete should come away from the EPDM without too much hassle.  As I suggested earlier, cutting the concrete with a diamond disc cutter to just below the depth of the rebar may allow it to be lifted away in chunks.  It'd need a proper disc cutter, with a depth stop, but you can hire one of those, like this: https://www.hss.com/hire/p/floor-track-saw-petrol-350mm

[Triassic]

I’ve just read the whole thread and realise what a big problem you’ve got! You’re right, the whole lots got to come out and be re-done. As Jeremy says you need a good craftsman with an eye for detail. Have you talked to the EDOM manufacturer, maybe they have a technical expert who could advise on what needs to be done and who would be best to do it.

[Pocster]

7 minutes ago, JSHarris said:

 

I think you're in for a lot of work in ripping the existing concrete and pavers off, and, as the problem seems to be entirely a result of bloody awful workmanship by the "roofers" that laid the membrane I can't see any reason why you can't just lay a new layer of EPDM over the roof (after getting back to the existing EPDM), with proper detailing around the upstands and edges.  This roof can be made to work OK, it just needs good workmanship.  The chances are that the existing EPDM can just be trimmed back around the upstands and a new layer laid directly on top of it, I think.

 

Heck of a lot of work, but with luck the concrete should come away from the EPDM without too much hassle.  As I suggested earlier, cutting the concrete with a diamond disc cutter to just below the depth of the rebar may allow it to be lifted away in chunks.  It'd need a proper disc cutter, with a depth stop, but you can hire one of those, like this: https://www.hss.com/hire/p/floor-track-saw-petrol-350mm

Agreed 

But I’m still unhappy with a potential leak in the future  . I’m want my rubber roof accessible.

 

good workmanship seems to be in limited supply 

Edited October 19, 2018 by pocster

[Jeremy Harris]

4 minutes ago, pocster said:

Agreed 

But I’m still unhappy with a potential leak in the future  . I’m want my rubber roof accessible.

 

 

EPDM has a pretty good reputation for long term reliability, and when encased in concrete I'm certain it would outlive you.  The only slight risk is that the EPDM could get damaged when laying the concrete, but I think you'll find that all the EPDM underneath your layer of concrete is fine, and that the problems are all associated with the detailing at the upstands and edges.

[Triassic]

Thinking out of the box. Maybe talk to a car park waterproofing company and ask how they do it?

 

https://www.tremco-europe.com/en_GB/home/download/9400/download.html

 

http://www.lrwa.org.uk/wp-content/uploads/2015/07/LRWA-Car-Park-Code-of-Practice.pdf

Edited October 19, 2018 by Triassic

[Pocster]

25 minutes ago, JSHarris said:

 

 

EPDM has a pretty good reputation for long term reliability, and when encased in concrete I'm certain it would outlive you.  The only slight risk is that the EPDM could get damaged when laying the concrete, but I think you'll find that all the EPDM underneath your layer of concrete is fine, and that the problems are all associated with the detailing at the upstands and edges.

I agree again 100%

But I’d have to break out 35mm of reinforced concrete ( and there is a risk I could damage the rubber ) . Equally as you say I could damage any new edpm with a new concrete pour - I’m then back at square 1 . I’d rather have a rubber roof that can be serviced . You are probably right I know that . But  I’d sleep better with a new rubber roof that can be accessed if any issues . I don’t want to hear that drip drip in the night .... ?

Edited October 19, 2018 by pocster

[Triassic]

If you look at the car park waterproofing link it looks like some of their systems use resin bonded decorative stone as the top coat. Maybe you could finish the parking area with something nice looking, rather than black rubber.

[Pocster]

Just found that the company that do those feet also do a protection mat deliberately to stop it damaging the rubber . 

Good news .

[Mr Punter]

16 minutes ago, pocster said:

Just found that the company that do those feet also do a protection mat deliberately to stop it damaging the rubber . 

 Good news .

 

Pedestrian or vehicle?

[Pocster]

3 minutes ago, Mr Punter said:

 

Pedestrian or vehicle?

Pedestrian; but that’s ok ; only need it to the sides of my parking bay 

[PeterW]

28 minutes ago, pocster said:

Just found that the company that do those feet also do a protection mat deliberately to stop it damaging the rubber . 

Good news .

 

I think you’re making work for yourself and even creating a bigger issue. You could be creating problems with differential movement between the concrete and the slabs. Also, how will you drain under the slabs ..??

 

I would be looking at leaving what is there and capping over with a new fully waterproof - and guaranteed - membrane and then finish that with something removable. 

[Pocster]

4 minutes ago, PeterW said:

 

I think you’re making work for yourself and even creating a bigger issue. You could be creating problems with differential movement between the concrete and the slabs. Also, how will you drain under the slabs ..??

 

I would be looking at leaving what is there and capping over with a new fully waterproof - and guaranteed - membrane and then finish that with something removable. 

If I have a new rubber membrane over the concrete that’s great . But I still have to make the fall and bed the pavers in concrete - therefore covering the rubber in concrete again effectively.

Draining under the stilted slabs is the issue ; due to no fall . That needs to be solved somehow .

[Declan52]

New membrane over existing concrete. 

Bed of sharp sand 10mm deep. 

Dry screed laid with a fall to an edge . I would mix plenty of waterproofing into the screed. 

Pavers on top of dry screed. 

 

At the lower edge of the roof where  any water that gets through the pavers and underneath the screed your going to have to come up with something here to drain any water away. Can you form some sort of gulley here where it will come out of an upturned section of edpm into a pipe and away to a gulley or manhole??? 

For the  drainage on the top you could  form a channel in the dry screed using some 50mm pipe and have this running from the edge to where ever you have a manhole or galley. 

[Pocster]

6 minutes ago, Declan52 said:

New membrane over existing concrete. 

Bed of sharp sand 10mm deep. 

Dry screed laid with a fall to an edge . I would mix plenty of waterproofing into the screed. 

Pavers on top of dry screed. 

 

At the lower edge of the roof where  any water that gets through the pavers and underneath the screed your going to have to come up with something here to drain any water away. Can you form some sort of gulley here where it will come out of an upturned section of edpm into a pipe and away to a gulley or manhole??? 

For the  drainage on the top you could  form a channel in the dry screed using some 50mm pipe and have this running from the edge to where ever you have a manhole or galley. 

The architect originally wanted the pavers bed in concrete for extra waterproofing ☹️.

This still puts water level potentially flush with sky lights although you say a drain . Surely the stilted pavers mean the skylight glass never gets water anywhere near the top .

[Onoff]

I'll say out loud I think it insane to have an inaccessible waterproof membrane under concrete. Under removeable pavers fair enough.

[Pocster]

6 minutes ago, Onoff said:

I'll say out loud I think it insane to have an inaccessible waterproof membrane under concrete. Under removeable pavers fair enough.

This is my main worry now and water at skylight level . The solution I have solves those issues . Some thought on falls and drainage make it do able . No way am I concereting over rubber . Even if it was leak free I don’t want to be posting back here 20 years later I have a leak . I want my rubber to be like any other roof I.e I can get to it 

[Jeremy Harris]

If it were me I'd want the EPDM well-protected from damage.  Having it encapsulated under concrete makes it pretty much bomb-proof, and far less likely to be damaged than having it partially exposed.  If it does get damaged in the exposed areas then I would guess that sods law says that the whole membrane will need replacing, including the area under the concreted bit in the middle, so just as much work to fix.

 

There's no difference between an encapsulated roof membrane like this and the DPM under our concrete slab, that keeps the damp out.  If our DPM fails then the whole house has to come down in order to fix it, as the slab runs under our walls.  What's more, our DPM is a much thinner sheet of polyethylene, nowhere near as robust as a 1.5mm layer of EPDM.