Leaking Parapet Gutter - Fitted 3 years ago

[tfman]

Hi,

We had the front parapet gutter on our house completely replaced about 3 years ago.

It's been fine until storm Alex a couple of weeks ago. Then a wet patch appeared in the room below.

I left it for a couple of weeks to see if it was a one-off due to the large amount of rain. However, it has persisted and the wet patch got larger again when it rained again this week.

I've had a look at the gutter through a velux window in the roof. I've attached some photos. Sorry if they are not very good. I can get some more, if needed.

A couple of observations:

• There was a large amount of dirt collected around the area of the leak, which I have now removed.
  
• I think (not 100% sure) that there is pooling around this area too. My guess is that this is why the dirt seemed to be collecting in this particular area.
  
• The area of the leak is directly under a join in the lead. You can see the join in IMG_6897.JPG

I spoke to the builder this week and he said he will come to have a look next week. He also mentioned "a liquid solution to solve that". I am assuming it will be something like Acrypol, which I thought was a fairly short term solution for patch repairs.

Is that right? What would be the recommended solution?

I am assuming a new lead gutter is meant to last more that 3 years, so I am not best impressed.

I am not sure what legal position is though. Can I actually legally get him to do a better solution? Or if I was better than acrypol, will I have to get someone else out to fix it?

Thanks in advance for any advice!

 

[Makie]

What is the joint done with? Is it welded or a step?

 

[tel765]

Like Mackie's question what kind of join is that? It looks like an overlap thats been folded? The gutter is too shallow in falls to give a clean discharge. Ponding's not acceptable in any kind of gutter. It should have dropped in steps. You will have to get on the gutter and clean it off to look for cracks. The lead should only be in 1.5m lengths max. A welded join will split. How the tiles meet the gutter looks wrong, is there an upstand below the first tile course?
The parapet capping looks a bit wonky and maybe the cappings are loose fitted?
Have you had a look at the rafters and gutter from below in the loft? Look for damp or rot.

 

[Makie]

The lead should only be in 1.5m lengths max.

That's not quite the case, it all depends on the code used. This however is probably only code 4/5 based on how it's finished

 

[oldbutnotdead]

And do you know how far up under the tiles the lead goes? Looks as if there's zero or fractional clearance from tile to lead (which isn't clever, you could get water creeping up in a zero gap by capillary action, I'm wondering whether thats why the bottom 75mm or so of the first tile course looks dark.
If water has got up under the lead you'll get staining etc inside for a while (if there's rockwool insulation in the roof space).
I'd have to agree with you about leadwork should last a bit more than 3 years without leaking, a quick look at Calder's Guide to Leadwork says that gutter is a design fail, the joints should be stepped, that looks like a lap joint (would be pointless welding it, you'd be straight back to expansion problems).
Refitting it properly would be impossible without some major disruption. As someone else pointed out, there's not enough fall on it either.
The liquid solution will be temporary (thermal expansion will cause the lead sheets to move relative to each other so the acrypol/whatever will eventually run out of flex and start leaking again).
The only longterm fix I can see which wouldn't be excessively disruptive would be GRP. Pity, builder used the best material for the job but hasn't installed it properly,

 

[tfman]

Thanks for the responses!

I will get back up there and take some photos of the join and have a look for any cracks.

Looks as if there's zero or fractional clearance from tile to lead (which isn't clever, you could get water creeping up in a zero gap by capillary action, I'm wondering whether thats why the bottom 75mm or so of the first tile course looks dark.

How the tiles meet the gutter looks wrong, is there an upstand below the first tile course?

Yes, I saw this too, but forgot to mention it. I think this is why they are getting wet like this, yes.

I am assuming that the tiles are not meant to rest on the gutter in this way. How should it be? I assume there should be some drop from the tiles to the gutter?

What is the joint done with? Is it welded or a step?

I believe it is stepped. I can see gradations in the lead, which I assume are due to the steps. Hopefully the next photos should clarify.

Have you had a look at the rafters and gutter from below in the loft? Look for damp or rot.

I've had a look, but couldn't spot anything. It is difficult to get close though. I'll have another go this weekend.

The liquid solution will be temporary (thermal expansion will cause the lead sheets to move relative to each other so the acrypol/whatever will eventually run out of flex and start leaking again).

Yes, I thought that might be the case. Thanks for confirming!

The only long term fix I can see which wouldn't be excessively disruptive would be GRP.

Properly refitting it would require part of the ceiling in the room below coming down?

 

[tfman]

The lead should only be in 1.5m lengths max.

The building is about 5m wide, so I will check the number of joins over the weekend.

The parapet capping looks a bit wonky and maybe the cappings are loose fitted?

I'll check these too while I'm up there, but I don't think they are loose fitted.

 

[tfman]

Overall the roof is quite old, though obviously the gutter is pretty new.

I was expecting to have to replace it at some point, but was hoping not yet.

I might take some photos as it would be useful to get some feedback. If I need some proper work redone on the gutter, then it might make sense to look at the rest of the roof.

 

[Nige F]

overlap thats been folded? /QUOTE]

that's a welt, ted

 

[tfman]

Sorry for the slow response. Took me a while to get up and take some photos.

I've been in the loft, but I can't see any wet patches. Attached are some photos.

It it hard to get up close. I suppose I will have to have another go because there must be a damp patch somewhere.

One thing you can notice is that the gutter goes up quite high, so I don't think it can have gone up above that.

 

[tfman]

Here are some photos of the lead work around the area of the leak, including a close up of the suspect join.

I can't see any cracks, but maybe I am missing something.

One thing I haven't done is look at the join under the roof tile, which I suppose I should to too.

 

[tfman]

Also, here are some photos of the parapet wall and the lead gutter.

 

[tfman]

Finally, in terms of the roof being old and not looking in great condition as a whole, here are some photos of the felt and the lead flashing on the chimney stack.

As you can see the felt is not in great condition. Also the gap between the flashing and the tiles around the chimney seems large to me.

Down the line (probably 2 to 3 years) I am planning to get external insulation on the back wall, so I assume I will need adjust the roof and guttering at the back of the house at the same time.

I am wondering whether to do a temp fix on the front gutter until I get this other work done. Not sure if this is a good idea or not though? Or should I look to get GRP fitted now?

 

[Nige F]

Looking @ the tiles - Redland 45's ( similar to Marley Ludlow ) Red.s are bowed Marleys are flat. And your decayed felt, plus the leadwork , I surmise that it's a 1970's re- roof job. It has all the signs - a lot of people got rich in the 70's doing those roof jobs . Maybe it was a slate roof originally. Patch with acrypol for now.

 

[tfman]

cool, thanks.

Yeah, I believe it was slate originally.