Leaking flat roof, can't identify material, need help with a fix!

[Ges1]

Hi everyone,

We've got an old kitchen extension that was done in the 80s. Absolutely no insulation in it, and the central roof lantern has been leaking for a while. I've inspected the roof, and found that the drain off point is in the middle of the roof, right by the corner of the lantern, and it goes through the roof and out to the edge of the extension.

Here's a couple of close ups of the drain off point next to the lantern where the leak is occurring:



And here's nother random image of the material I hope someone can identify. It's a flexible material that feels very spongy and stretchy.



Could anyone advise me on a proper fix for this? I believe the leak is in between where the rubbe meets the plastic drain somewhere in the hole, and identically I'd like to fix from the outside with new material I can attach and feed into the hole itself, but will take different advise if there's a proper/better way

Thanks so much. This is kind of urgent because it's raining but tomorrow is dry and it's the weekend, so perfect timing to get it sorted!

 

[accelerator]

Is the material EPDM?

If there's a drainpipe running from the drain hole to the building exterior have you check it's not blocked?

 

[Ges1]

Oh wow yes, it may be that, thank you! Yes, definitely not blocked as far as I can tell, as it's still draining pretty well, and the site of the leak is when looking through the hole I've cut in the ceiling is directly below the hole

 

[accelerator]

How do you know it's not a joint in the plastic piping that's leaking? Can you show a pic of the drainage hole and plastic piping from below?

 

[Ges1]

Am I looking for something like this:

https://www.permaroofstore.co.uk/epdm-drain-outlet-100mm.html

 

[accelerator]

How do you know your plastic piping hasn't cracked?

 

[Ges1]

Because it's far less likely to have happened than it being the rubber, which has clearly deteriorated to the point where it's peeling off and rotted away. The plastic is completely fine

 

[Harry Bloomfield]

Here's a couple of close ups of the drain off point next to the lantern where the leak is occurring:

Check that drain, is not blocked! A length of net curtain spring, might be all you need to clear it.

 

[Ges1]

Thanks Harry, I just did that with a bit of tubing and got a little out. Also tested the pipe with a hose and left it running just beyond where it joins to the rubber, and no leaks of any kind visible. It does appear to be right at the point of the two pictures posted.

If anyone has any ideas on a repair, I'd appreciate it.

 

[Harry Bloomfield]

Thanks Harry, I just did that with a bit of tubing and got a little out. Also tested the pipe with a hose and left it running just beyond where it joins to the rubber, and no leaks of any kind visible. It does appear to be right at the point of the two pictures posted.

Might Black Jack bitumen paint work? It just daubs on with a brush, and quite thick.

 

[Ges1]

That's why I'm here mate, I don't know what will work! Is that a known method for fixing broken EPDM? I just need a direction to go in as I'm completely clueless about this haha.

 

[Scally-Ho]

To this old chap, the roof covering reminds me of Nuralte. That was 'welded' together with a bituminous block and flame, so I would expect any sort of hot bitumen would do the job of leak fixing.

 

[Ges1]

Nuralite seems to be very specific to New Zealand, and everything I'm reading about it suggests it's very gritty, course, and quite rigid, whereas this is rubbery, elastic, and quite smooth.

 

[Harry Bloomfield]

That's why I'm here mate, I don't know what will work! Is that a known method for fixing broken EPDM? I just need a direction to go in as I'm completely clueless about this haha.

Get a tin of Black Jack, and try it - see how well it sticks. It cannot do any harm..

 

[Ges1]

But it can do harm, because it's bitumen-based, which will attack the rubber because of the solvents.

I appreciate the help, but I can speculate on what will work myself; I'm still just looking for specific advice from someone who knows the best method of first identifying what my roof materials, and secondly, what is the professional way to repair it myself.