Musty smelling carpets

[Ijustwanttodrinkmytea]

The carpet in our sitting room smells really musty and I'm trying to work out what's causing it, help!
There's no obvious damp patch, but I found a coaster under the sofa which has a slight white dusty coating, which I think was caused by damp? We did rent a carpet cleaning machine years ago and got them a bit too wet, but this was 3 years ago and the smell has only appeared recently. It's most noticeable at the front of the house, where the driveway slopes down towards the house, so I wonder if there's insufficient drainage? I've tried lifting the carpet at the edge to look under it, but it's very firmly attached! I'm not sure how to get to the bottom of this or who I can contact to help. Any ideas please?

[PigletJohn]

Wooden floor or concrete floor?

[Ijustwanttodrinkmytea]

Wooden floor boards, 1930s house

[PigletJohn]

look under the floorboards. Is it wet or damp? You mat hind it easier to take up a board near the front door or under the stairs.

Look at the walls of the house. There should be a DPC, a black line of slate probably. It should be about two bricks above ground level.

Look at the airbricks. How many, how far apart? Are they blocked? It can be done by raised ground, or a porch, conservatory or extension.

If the ground level has been raised (this is common) or directs rainwater to lie against the walls, this will cause damp.

Have you got a water meter?

[Ijustwanttodrinkmytea]

Thanks for all those pointers, very useful. The outside is pebbledash so can't see any DPC, but I'll try and find the survey we had done when we bought the house to see if it mentions DPC. The air bricks look ok, I dug out a bit of soil a while ago but they weren't very blocked. On the survey it did mention that we could consider upgrading the air bricks at some point to improve ventilation, but it wasn't listed as a major concern. The area at the front of the house does look like it might have been raised ages ago when the driveway was built (Tarmac) as the tarmac runs right up to the front of the house. What sort of tradesperson would be best to help if we do have a problem? Should I just google damp specialists? Thanks again

[PigletJohn]

damp specialists are liable to be salesmen for chemical injection firms, and may try to get you to buy chemical injections.

Very often the water runs towards the house, which adds damp, and if the airbricks are obstructed they will reduce airflow under the floor, which is intended to keep it dry.

Pebbledash should not run right down to the ground as it will bridge the DPC.

If you can get a recommendation for a small local builder he should be familiar with these.

typically, a small trench against the house wall will allow water to drain away, and it is filled with pebbles or cobbles (they are too big to allow water to rise by capillary action) also known as a French Drain.

If you have downpipes from the gutters discharging by the house, see there is no spillage and the drain is not broken or clogged.

Post some photos for a better idea.

You ought to look under the floorboards to see how damp it is.

Have you got a water meter?

[Ijustwanttodrinkmytea]

Yes I was worried about damp specialists selling me an expensive solution! No we don't have a water meter. Here's a photo of the front air vent...

[Ijustwanttodrinkmytea]

I'd be more comfortable with a local builder so will try that, thanks for the advice

[PigletJohn]

the look of that airbrick makes me think that the ground level is about six inches too high.

Lazy builders who can't be bothered to dig before laying a drive.

Not only is it probably defeating the DPC, rainwater may actually run through the airbrick into pools under the house.

I still think that digging a trench to lower the ground level, and filling it with cobbles, will be the best move. The DPC will probably be found when digging; if not, chip away some pebbledash until you find it.

When/if you relay the drive, slope it away from the house for at least a path's width. Diggers and skips make it pretty easy. You might need to design in a gutter and run the drainage to a soakaway.

[Ijustwanttodrinkmytea]

That makes a lot of sense, it does look like the ground level is too high. I'll get in touch with some builders or ground workers and see if they can dig a sort of trench. Thanks so much for your help.