PVC section on cast iron water down pipe.

[Suppressionfitter]

Guys

I have just moved to a new place and was about to start painting and sealing the gutters and down pipes. The house has a cast rainwater/waste water down pipe (not soil pipe) that has had a section replaced for pvc. The section is one up from the ground. Is this alright? Should it all be cast or all pvc?

There's no leaks and as I said above it's not connected to the WC just the sink and gutters. Would prefer not to have to change the full down pipe just for this section but don't want to not change it if I'm going to get issues further down line, like if we sell on in the future.

Any advice?

Cheers

 

[Hugh Jaleak]

If its not leaking it should be ok, my only advice would be to check the structural integrity of the cast above the plastic. Cast is very heavy, and can rely on the pipework below for support, plastic doesn't always offer a sufficient level of support.

 

[KenGMac]

Suppressionfitter, good evening.

As Hugh has posted, a length of Plastic has to be considered as slightly suspect given there is a shall we call it a large "lump" of Cast Iron pipe above the plastic pipe, as such there will be a load impinging on the Plastic pipe.

But in your original post, you do not give the board a clue as to how much Cast is in effect resting on the Plastic, likewise you do not mention how much Plastic there is?? This is by no means a criticism, but? the various lengths could have a bearing on the replies you get, lets not be pedantic the question is just to get a feel for the overall dynamics of the post.

Ken

 

[Suppressionfitter]

Sorry for the lack of info. Was really more concerned with the mixing of the two types, hadn't really considered the weight. There's around 2.5/3m of cast on top of a plastic section of around 1.5m then another cast section of 1.5m. Each section does have lugs and bolted to the wall and just above the plastic piece is the horizontal section to the sink in the bathroom. The integrity of the plastic looks good and there isn't any sign of sagging or fracture, just wanted to make sure that it wasn't a case of it being totally wrong.

 

[Hugh Jaleak]

If its water tight then it's fine. I'd just give it a gentle tug before you paint it, any movement in the cast needs investigating and rectifying before you do any more. It'll take no prisoners if it was to fall.