I need to introduce fresh air to my cellar on a constant basis, like a positive ventilation system. It’s a bit damp and musty. It has a door to the back garden (sort of a semi cellar) which when I’ve had it open for a while makes the cellar so much nicer and fresher so a nice constant flow of fresh air is proven to work well.

But what do I use? Shower fans are too noisy and I think pump too much air I think?? Need a slow moving fan which is fairly quiet

Any ideas?

I think you may be better pulling the musty air out rather than force air in from outside. Any way to get a pair of vents to create some airflow?

We had a positive pressure doofer put in to our stairwell (sounds grander than it is- social housing) because we had damp on the north east corner (again, sounds grander than it is- 2 up, 2 down) and it’s worked a treat. It just gets fresh air moving about and helps to keep things dry and it’s really quiet.

To do this ‘properly’ you need to consider how many ‘air changes per hour’ you need, and specify a system from that.

Ideally you need air being introduced to the room on one side, and removed/extracted on the opposite side.
If you just blow air into the room from one side you will not get a decent spread of fresh air through the room.

Can you add a small extract point on the opposite side?
Shower fans are designed to pull a lot of air through a small pipe as their purpose is to remove damp air from the room ASAP – you are on the right track with thinking they pull too much air for your application.

If possible I’d try to fit a small fan supplying air into the room on one side, and a small extract fan opposite – this would be even better if the supply fan is down low and the extract fan up high.

I’M not sure what is commercially available to do this job, as I work on slightly bigger stuff, the last HVAC system I was involved with supplying was on here –

http://www.greenwood.co.uk/range/18/continuous-extract.html?u=3

I used to fit a fair few of these sort or systems. They work well.

Noctua industrial fan?

Noctua NF-F12 Industrial PPC 2000RPM IP67 PWM 120mm High Performance Fan

Shower fans are too noisy

We have a ‘silent’ extractor fan and it lives up to it’s name.

When he installed the electrician thought it wasn’t working and put his fingers in to wiggle the blades – they were turning…

It’s still near silent 5 years later.

As above, I’d suck the damp air out to the outside not push fresh in – if there’s access to the cellar from within the house the positive pressure will just force the ‘bad’ air up into the main building.

pretty sure it’s this one;

https://www.tlc-direct.co.uk/Products/SLSD100CZ.html?ad_position=1o2&source=adwords&ad_id=45425533757&placement=&kw=&network=g&matchtype=&ad_type=pla&product_id=SLSD100CZ&product_partition_id=174056526787&test=finalurl_v2&gclid=CjwKEAjw6e_IBRDvorfv2Ku79jMSJAAuiv9YNzR5p0vxXOrD9XC30icB3G1579bQUKj1DNlEILbXDxoCZ_vw_wcB

If you extract damp air out it will just pull more dampness in through the below ground brickwork in the cellar rooms. Pumping fresh air in stops that, and damp air is forced out all the natural gaps.

Depending on the rest of the house, you probably don’t want to be drawing air from the rest of the house down into the cellar.

If the cellar is cooler, the air from the house will condense and actually make it more damp.

The ones that sit in the loft of houses work on the assumption that the air up there is dry, but warmed by waste heat from the house below (i.e. already got past the loft insulation).

If you extract damp air out it will just pull more dampness in through the below ground brickwork in the cellar rooms.

No, it will pull fresh air in from outside through the ‘natural gaps’ (proper vents would be better). The changes in air will gradually dry out the brickwork.

We’ve got a Vent-axia Tempra fan in our utility room where we dry clothes; it exchanges air via a heat exchanger and works well. It’s on the outside wall but circulates air quite well as the temperature difference, while small, means the fresh air sinks, rises up the far side and returns to the fan higher up.

There are a few similar “single room MVHR” devices; the Tempra one was the cheapest, but there are others that automatically change speed with humidity and whatnot.

I’ve used a passive flue to ventilate the underfloor of a house after a ground contamination event. A stack up to chimney height with a damper and controllable trickle vents.

It’s a Cannabis farm isn’t it?

Cellars often have high Radon levels. Have a look here:

http://www.ukradon.org/cms/assets/gfx/content/resource_3570cs43b5284266.pdf

Either way it gives some useful info on ventilating one.

Cellars in granite areas often have high Radon levels. Have a look here: