Hidden downpipe?

no nails niall

Hello,

Im putting drawings for my self build through building control. I'm going for a concealed gutter and also hoping to drop the downpipe down the cavity. Has anyone experience of doing this? Cavity is 100mm and downpipe also 100mm. Will they ask for insulation?

Niall

sinnerboy

Bad idea. If you break the thermal insulation you will cause a thermal bridge and localized condensation, possibly mould.

Supertech

I'd agree with sinnerboy here. Just had this conversation yesterday. There's a whole raft of issues with running it in the cavity (unless you've designed it in to work that way)

Why not leave the cavity as it is and bring the downpipe in a duct internally ? You'll need to insulate the duct for sound, and it's more risky than bringing it down externally but still achieves the concealment of the pipe, and in the event of an issue with the pipe later on you only have to strip the facing off the duct rather than carry out a large amount of opening up.

Gulliver

Our architect had internal downpipes on our plans but one ran through a downstairs bedroom and one through the dining room. Didn't like the idea of hearing every flush coming down and the fact there was this stupid 120 x 120mm box in the corner so I put them outside. Bearing in mind I hate seeing pipes on the outside of a house, I feel this was the right decision.

Also, how does venting work on hidden pipes?

Supertech

Gulliver wrote: »

Our architect had internal downpipes on our plans but one ran through a downstairs bedroom and one through the dining room. Didn't like the idea of hearing every flush coming down and the fact there was this stupid 120 x 120mm box in the corner so I put them outside. Bearing in mind I hate seeing pipes on the outside of a house, I feel this was the right decision.

Also, how does venting work on hidden pipes?

The OP is referring to a downpipe from a gutter which does not need to be vented.

Ventilation is necessary on soil pipes (from sanitary appliances) which are run internally Gulliver, as a rainwater downpipe will obviously have an opening at the top anyway.

Normally on an internal soil pipe, the pipe would be run up to the roof line and be finished with a purpose made vent tile, and the junctions all sealed It could be run through the roof to finish above the tile and finished with standard vent cap, but a vent tile is probably a better finish.

Sound insulation is vital around a soil pipe which runs in an internal duct.

FesterBeatty

If there is ever a leak - you're f*(ked!

tred

FesterBeatty wrote: »

If there is ever a leak - you're f*(ked!

or what about even a serious blockage. For e.g, i had one on side of my house last year, where some kid threw the empty inside roll of cellotape on roof, worked its way down to the side down pipe, got caught up with leaves, and we had to take it down to free it...if that was locked inside , i was in big trouble, all the rods in the world!.

Mellor

I've seen pipes coming down in the outer leaf. i'd rather that that cavity, but tbh, I asking for trouble either way.
Downpipes are open to the elements and much more risk to problems compared to SVPs.
For a start, in heavy rain the volume is greater, then there is leaves, and of course the dreaded empty cellotape roll

Gulliver

Supertech wrote: »

The OP is referring to a downpipe from a gutter which does not need to be vented.

Ventilation is necessary on soil pipes (from sanitary appliances) which are run internally Gulliver, as a rainwater downpipe will obviously have an opening at the top anyway.

Normally on an internal soil pipe, the pipe would be run up to the roof line and be finished with a purpose made vent tile, and the junctions all sealed It could be run through the roof to finish above the tile and finished with standard vent cap, but a vent tile is probably a better finish.

Sound insulation is vital around a soil pipe which runs in an internal duct.

Ah just the gutter downpipe. Sorry, misread that. The 100mm bit stuck in my head, so I thought it was both pipes (in my mind 75mm downpipe and 100/110mm soil). The soil pipe on our plans did not break the roof line and there was no detail for venting, which I thought was strange.

As for sound insulation, that was on the plans but I didn't think it would mask the sound totally. I really didn't want to lose the internal space with a box in the corner though.

OP, for a hidden gutter/pipe, you know the water harvesting idea that was on Dragon's Den where there was a "gutter" on the slope of the roof? Well they went through the roof with the water. Invisible from the ground. Would it be possible to go in at the eaves from your hidden gutters into the roof space using something like a u-bend and either use the roof water or dispose of it through a hidden pipe inside the house? Also if it was collected in a tank before disposal would it be a steady flow and less noise and not a rush/drip when it rains?

Or am I talking through my arse again?

tred

Mellor wrote: »

I've seen pipes coming down in the outer leaf. i'd rather that that cavity, but tbh, I asking for trouble either way.
Downpipes are open to the elements and much more risk to problems compared to SVPs.
For a start, in heavy rain the volume is greater, then there is leaves, and of course the dreaded empty cellotape roll

dont be laughing, it made no sense until we got it out!, i thought it had to be a critter in there the blocakge was so bad with leaves and crap ontop !!