Ventilating Cellar

20 Jul 2020
Reaction score
United Kingdom
Hi all

First time poster here. Sorry if this is on the wrong forum/topic has already been covered.

I have what I would refer to as a "split cellar". Front half of basement level is traditional type cellar back half opens out into 'ground level'.

The cellar (front) is very damp and humid. Current RH reading is 99% (). I know it needs ventilated but I'm not sure exactly how to do this. I don't own anything further forward than my front door as my house is right on the pavement. I originally thought of getting someone in to install a periscope ventilation system to go out if the cellar ceiling, into the floor above and then through the external wall? Would that be sufficient?

Also, the cellar wall is very damp. Positively wet. I've noticed cracks between the pavement flags outside my front door where the cement has worn away. Would rain water getting in there be contributing to making that cellar wall underneath wet?

Sponsored Links
Ian, good evening.

OK, as I see it, your cellar extends under a public footpath??

You do not own this area of "the" cellar?

My immediate reaction is that you cannot "do" anything to an area of property that you do not own, if that makes sense?

As for "options" ? close of the area of cellar you do not own and should have no access to?

Or?? ask the "owner" of the Cellar to take some steps to remedy the dampness and water ingress which could / may / is affecting your property? if that is the Local Authority??? do not hold your breath.

As an aside? was this area of cellar extending below the public footpath a Coal Cellar? if so is there an old manhole in the pavement?

I read it as Ian owns the cellar but as soon as you're past the brickwork at the front of the cellar, you're under the pavement which Ian does not own.

My tuppence worth: You could stick some ducting to pull air from the back through to the front of the cellar. That would let you draw fresh air to the damp section and then exhaust it at the other end of the back. You'd need a powered fan for that, probably on a timer or just permanently running.

You could have some sort of snorkel into an air brick or two at the front, that'd also let you get some ventilation through the space.

Tanking is possible but that always appears to be a major pain.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Sponsored Links