Venting a disused flue through slates in a conservation area

Postby RJC » Mon Jul 26, 2010 10:30 am

Hi there....first post so a bit new to this,

I have damp in a diagonal line that follows a dis-used flue in an upstairs bedroom. The old chimney has been removed, slated -in and is open to the loft space. I suspected a condensation problem so have left the old flue open in the kitchen (covered in plastic shroud) and drilled what is effectively an air brick into the flue in the upstairs bedroom. This has made no difference and the condensation is so bad that water is beading on the inside of the felt in the loft space.

I also now realise that the render on the granite wall in the bedroom will be heavily contaminated with hygroscopic salts so I am planning to completely strip back to granite and re-render with salt inhibitor and tanking solution (probably the Heidi K11 system as this has worked well in other areas of the house).

My question is that I do not want to leave all that condensation pooring into my loft and I want to vent the flue back out through the slates and via a stainless steel pipe and cowl but in the village where I live there is no way stainless steel would be allowed. So does anyone know of any different kind of vents that can be built into or protrude through the natural slate roof?

Also some people have suggested filling the old flue with vermiculite to stop condensation altogether? Does this work and would it not eventually become a big sponge holding damp within the chimney?

Any help would be greatly appreciated.
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Simply Build It

Postby stoneyboy » Wed Jul 28, 2010 10:38 pm

Buy a slate vent and connect the flue to this.

DIY doctor have decided to add a reply to all posts.
This makes it difficult to keep track of subsequent messages so if you want further advice please leave a new message.
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Postby RJC » Sat Jul 31, 2010 4:47 am


cheers for the response. I am now looking into this solution. Should be pretty simple too.

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Postby oli-spark » Wed Aug 25, 2010 2:18 pm

stoneboy is spot on
all i would add is that you can get some totally flush slate vents that should cause no offence to anyone.
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Postby RJC » Mon Feb 28, 2011 9:15 pm

Thanks to all that responded. Flue is now connected to and venting through a roof tile. RJC
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Joined: Mon Jul 26, 2010 9:34 am

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