Leaking Drain/Gully - Damp wall

[mallangong1]

Hi,

We have an old flat roof kitchen extension to our property (60's judging from the planning dates). There is obvious damp affecting one external wall, the same wall has damp on a smaller section of the internal wall. A bit of digging around this weekend as shown that where the waste water exits into the gully/drain (I'm not sure of the correct terminology) it quickly leaks out of the back left corner of the concrete surround and so into the surrounding soil.

So, my questions:

1. How do I fix this gully/drain? I presume I need to dig out the old concrete one and cement in a new one? If so where do I get one from and is it as simple as just cementing a new one in?

2. This explains the damp around that area on the external wall and I'm happy to say also corresponds to the damp part of wall internally. However as you can see in the photos there are some other areas showing signs of damp on the external wall. Are these caused by this drain/gully issue or are they separate?

3. I am think of rendering the whole section of external wall after the drain gully is fixed and bricks dried out. Do I need to do anything else after the drain/gully is fixed i.e. will the bricks/foundations be OK?

Thank you so much for any advice you can give. Also I hope it is OK that I have also asked for help elsewhere on the web - desperate to get this fixed so we can get the 60's kitchen redone.

Jim

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• mallangong1
• 8 May 2010
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• mallangong1
• 8 May 2010
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• mallangong1
• 8 May 2010
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• mallangong1
• 8 May 2010
• 1

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• mallangong1
• 8 May 2010
• 1

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• mallangong1
• 8 May 2010
• 1

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• mallangong1
• 8 May 2010
• 1

 

[2929twin]

Photos?

 

[mallangong1]

Sorry, added the album but didn't include them All up now.

Jim

 

[2929twin]

OK Now I see them. The concrete kerb around your gulley is a separate item to the gulley, but will be concreted in situ. If broken can be removed and replaced from most merchants, the gulley is a glazed pottery unit, which rarely caused many probs. if not disturbed. It looks like you need to start by cleaning out the gulley pot. A good blasting with hose/pressure gun will move the `scummy` stuff then hand down and pull out any stones, grit, toys etc.
Not many builders use the kerb in a paved area situation [stand to be corrected] the waste pipes from kitchen can be fed into the gulley direct, just 20mm through the grid plate, that way there should be no splash out. If the gulley is in one piece, check if the first joint is cracked out, if so a repair can be made with a sand cement mix. Obviously if broken needs replacing.
The wall section in photos seem to be not directly asociated with the gulley as there is no damage next to pot. And fairly unusual to rise so far up wall. More likely frost damage due to poor pointing. If you say damp internal hopefully good repair pointing will help. Render def. will.

 

[mallangong1]

Thanks 2929twin. Similar advice to what somebody else has also said - which is great. Sounds silly but there is a lot of satisfaction for an old git like me in fixing something I would otherwise have had to pay hundreds to get fixed.
I have

have taken the surround off, there was also a piece of concrete cemented on to form a back panel. Yes it is a clay water trap underneath. Due to the colour of the water and the black sludge around it looks to me that most of the waste water has been missing the drain for a good while (we only moved in a couple of months back).

My plan is to let it all dry out a bit today and then tomorrow replace the metal grill with a plastic one so that I can cut two holes in it for the waste pipes. I will extend the two waste pipes - not sure whether it should be best just to add small extensions or to replace the sections (especially as there are covered in fat). I will also replace the surround and backing plate - using the one I removed. Not too sure but presume I will just make a bed of gravel for it to sit on and then cement the whole lot in place.

Does that sound like the way to do it? So after I have done this do you think it would be best to strip back the paint and re point the whole wall or just render it?

Cheers,
Jim

 

[Nige F]

You got grey solvent weld waste there M8 just get some fittings and a tub of glue and a length of sol. weld pipe . extend them as said before then paint the lot with some gloss black - no undercoat needed . Looks good and works much better with the pipe through the grid . Should have been like that - but many are like yours was

 

[mallangong1]

Thanks Nige. Will get onto it tomorrow. Any ideas whether the leak could account for the damp showing through on the other end of the external wall? And do you think rendering would be the way to go now?

Cheers,
Jim

 

[JohnD]

examine the trap carefully. Sometimes the fireclay ones crack, especially when the top is restrained in concrete.

 

[mallangong1]

Right, well have re-seated the surround and have lowered the waste pipe levels through a plastic grill. I would post pictures but my cement work leaves a lot to be desired!

Can any body help about the the actual wall? i.e.

Does this explain the damp on the other side externally?
Is it best to render or re point/replace bricks?

Thanks,
Jim

 

[JohnD]

if the mortar has been eroded by leaking water, clean out all loose material (a water jet is good) and repoint, assuming the bricks are not loose. It will probably be underground so does not matter if you are not very neat. The damp conditions will help the mortar cure to a hard and strong level. Do not mix it too wet.

you might find red worms (they like drain leaks) which I am told are good fishing bait.