external air for stove - how to run into building

fclauson

So we all know stoves need an external air supply in an airtight house

how do you run the ducting into a stove which is not on an outside wall

a) under the sub floor and up (but then how would you terminate it outside and how do you make sure not moisture gets into it)

b) at the insulaiton level/plinth - but then this is a line of cold/uninsulated area from wall to stove

Thoughts ?

brdboard

fclauson wrote: »

So we all know stoves need an external air supply in an airtight house

how do you run the ducting into a stove which is not on an outside wall

a) under the sub floor and up (but then how would you terminate it outside and how do you make sure not moisture gets into it)

b) at the insulaiton level/plinth - but then this is a line of cold/uninsulated area from wall to stove

Thoughts ?

I ran the duct under the floor and turned it up in the wall cavity, and turned it out through the outer leaf. 200mm cavity so will still have some insulation behind the duct where it runs vertically in the cavity.

fclauson

brdboard wrote: »

I ran the duct under the floor and turned it up in the wall cavity, and turned it out through the outer leaf. 200mm cavity so will still have some insulation behind the duct where it runs vertically in the cavity.

Thanks - I have a 250mm cav - but you are taking 250mm down to 150mm full fill (assuming 100mm duct) - I am just concerned that you will have a cold spot on the wall - prehaps I am paranoid

any thoughts anybody


One other item - does bead interact with PVC ducting to a detremental effect ?

brdboard

fclauson wrote: »

Thanks - I have a 250mm cav - but you are taking 250mm down to 150mm full fill (assuming 100mm duct) - I am just concerned that you will have a cold spot on the wall - prehaps I am paranoid

any thoughts anybody


One other item - does bead interact with PVC ducting to a detremental effect ?

You are reducing your insulation thickness, but it's just for the length of pipe from under the slab to wherever you turn it out through the outer leaf, this should be less than a metre in length. Much less in length than if you brought it above the slab through your floor insulation.

I don't know about the PVC- bead interaction, I hadn't thought of that, but I would think it's no different to bringing a toilet soil pipe through a wall?

paddym3

i am planning on running mine under foundation out to my boundry wall and into the hearth of fire in side. it easy to disguise it with hedging after. also make sure you put in a bigger pipe then needed. the size might be right for stove now but if you replace in future you cant put in bigger pipe

john_cappa

How big a pipe does this need to be usually?

fclauson

This is what I am doing (see attached) - I am using a 6in duct

comments welcome

zrejvpx

There was a discussion on this a while back too, http://www.boards.ie/vbulletin/showthread.php?p=73985672.

I have to do something similar - 100mm air intake. I'd have my concerns about it coming up through the cavity (wouldn't it have to puncture the DPC) so your detail looks better (note take this opinion for what it's worth - I've absolutely no building qualifications, just a long-time reader here...)

paddym3

6inch is plenty bigg enough for all stove most require 4 or 100mm so 6 will give you a nice cushin for later,