Ventilation options for tanked chimney breast

[renol]

Im in the process of having my kitchen tanked with membrane - walls and floors. But wondering the best way to ventilate the chimney breast. On my other chimney i have vents at the bottom, inside the rooms. However poking holes in the new wall DPM mesh, in the kitchen, hopefully is not my only option! It has a cowl on the top, and my plan was ventilating from outside. However Ive read on a few forums that this could cause as many issues as it solves ... Any guidance would be much appreciated.

 

[blup]

No reason not to put air brick outside as long as its above dpc level, presumably its a single flue if serving just the kitchen.

Blup

 

[renol]

Thanks for the reply Blup. (Yep single flue on this chimney). Would there be any harm I wonder, if the ventilation hole was placed 1m+ or so high, or does it need to be near the base of the chimney ideally?

 

[conny]

The nearer the base the better in case you get a bit of condensation which would sink towards the base area.
If the fresh air is coming in there then it will help to keep it drier.

 

[renol]

Thanks Conny, that makes good sense. Ill see what i can suss

 

[blup]

If there is an old gravity boiler built into, and blocks off, the bottom of the flue that might interfere with air flow, otherwise ok.

Blup

 

[renol]

no nothing .. flue just goes straight to what is now an open fire place (think there was a solid fuel boiler at some point in the past.. )