Condensation on internal water soil pipe

[stefanr]

A friend has a 110mm brown soil pipe in the corner of a single story room that takes all the rain water from the main and a secondry roof. It was boxed in with mdf and insulated with that yellow glass fiber insulation. The lead on the roof is all welded all fits inside the soil, which in turn is joined via a coupling to another section concreted into the floor.

The other day he found that the floor, carpet and underlay, was soaking wet, he doesn't usually walk on that area so hadn't noticed, other than a damp smell building up over a couple of months.

After the boxing was taken down I went up and cleaned the flat leaded area to look for cracks, none and checked for leaks with a hose, again nothing. the coupling is sealed and didn't leak either. Then whilst it was raining very heavily the whole pipe formed with condensation which started to run down to the floor.

This looks like the cause of the problem and and being happening over a long period of time.

Is there anything that can be put around the pipe, which is close to the wall, that will eliminate the condensation????

kind regards

Untitled

• stefanr
• 27 May 2013
• 1

Untitled

• stefanr
• 27 May 2013
• 1

Untitled

• stefanr
• 27 May 2013
• 1

 

[Nige F]

Maybe the thin foam backed foil sheets sold @ diy stores to go behind rads - cheap . Or sheet Armaflex - expensive

 

[stefanr]

Maybe the thin foam backed foil sheets sold @ diy stores to go behind rads - cheap . Or sheet Armaflex - expensive

Thanks, would that be enough to stop the condensation building up? I have heard that the foam back foil stuff also condensates.

Armaflex is that the same stuff that plumbers use around pipes?

S

 

[Porque223]

The pipe temperature, relative humidity in the room and a chart can confirm if it's condensation and not something else.

If it is condensation another option besides a dehumidifier is to wrap heat tape around the pipe that is switched on with a humidistat & a relay.

 

[masona]

Maybe refit the box back with approximately 3" gap at top and back fill it with loose fill insulation then refit the gap or maybe with 4" coving just on the box section, have done mine this way without the coving method Will also be good for soundproofing as well

 

[Nige F]

Good idea from Masona - and yes, the sheet armaflex is used on large installs by laggers - so it`s kind of plumbing Worth a look on t`web for it. The thin DIY stuff might indeed not be "man enough"

 

[stefanr]

Cheers fellas, some good ideas.

My brother-in-law said if I can get the top section of the pipe off, then lag it maybe some carpet underlay taped tightly round or glued and then fill the surrounding area within the covering box with better (other than the yellow) insulation.

I also thought about sealing the gap at the top with expanding foam and drill some holes around the two sides of the boxing in at the top, 40mm down or even put a small vent at the top.

S

 

[Mw Roofline]

It is a conc floor isn't it? Just incase it is t&G board (hard to tell on my silly phone), cut the floor out inside the box to allow airflow.

 

[stefanr]

It is a conc floor isn't it? Just incase it is t&G board (hard to tell on my silly phone), cut the floor out inside the box to allow airflow.

Conc.