Damp behind fridge freezer

[Ozzy715]

I noticed some ants coming from behind the fridge so pulled it back and noticed that the brickwork below the plaster appears black with a few gaps that looks like they lead down below the floor.

I’m assuming that if the ants can get in then moisture or damp can get in? I haven’t seen any damp issues elsewhere in the kitchen so am hoping it is isolated to this area.

Any recommendations on how to remedy this? I was going to use a sealant to plug any clear gaps and then Zinsser Bullseye to add more of a waterproof seal to the brickwork.

Any tips or guidance would be appreciated
Thanks

 

[Scally-Ho]

OMG, someone's nicked the skirting
Age of the property and type of construction?

 

[Ozzy715]

so it’s in the kitchen extension (previous owners 10 years ago) but I believe this wall is one of the original Victorian walls (house is circa 1880).

 

[Scally-Ho]

Ah right, so this wall is the existing Viscorian property's outside wall that became internal due to the extension tacked onto the back, so I'm presuming solid brickwork. Now I'm guessing the black 'stuff' you can see is some kind of DPM painted on before the flooring was completed.

 

[Ozzy715]

It’s the original Victorian wall that is the back of the original kitchen that backs onto the neighbouring property. Thanks for the guidance on a DPC paint or similar. What would the indicators be if this was mould / damp? Using a damp meter?

 

[endecotp]

I don't think there is any damp, is there? You just say "if ants can get in then so can damp", which is a bit vague. If you can't see any signs of damp, then don't worry about damp. Just get a bit of skirting board, or something that will substitute for skirting board, fix it to the wall and paint it grey to match the other. (If you didn't know, the sort of gap you're seeing there is commonly found behind skirting.)

Regarding the ants, don't leave out things they like (mainly sweet things) and clean the floor, work surfaces, and the insides of cupboards if e.g. a bottle of squash has leaked. They will disappear once their food source has gone.

Damp meters - the sort with a pair of metal prongs - are designed for use on wood; using them on walls like this is not useful.

 

[Scally-Ho]

A 'damp' meter is somewhat unreliable for masonry walls due to the inconsistency of the likely composition. A cold solid wall in the alcove taken up by freezer will have mostly stagnant air around that back wall, so any moisture in the kitchen will be the cause of any condensation on that wall, and the comparatively glossy DPM will probably be the point at which the moisture will condense and possible attract mould from the spores constantly in the air we breathe. To make sure of any mould present a test kit can be bought from Amazon and then you can know what you are up against.

Amazon.co.uk

 

[Ozzy715]

Thanks everyone - you’ve been very helpful

 

[mrrusty]

Wack some sand and cement in the gaps, replace the fridge and get on with your life. The primary problem, of course, is the fridge itself. It will have a mechanism to defrost, and all the defrost liquid is then taken down in to some part of the fridge where it is evaporated. Guess what, that means there is a lot of water vapour around the base of a fridge. The bottom of that wall will be fairly cold - especially if it's victorian, so with a fridge there, there is always going to be some damp from condensation. IMO there's no easy fix.

Some fridges are better than others - the ones where there is a water tank over the compressor which evaporate from the open back are going to be worse than the ones that have a closed back and a grille at the front and a fan that moves the air and blows it out in to the kitchen.

 

[opps]

A 'damp' meter is somewhat unreliable for masonry walls due to the inconsistency of the likely composition.

Agreed. I once had a damp meter. They are great for timber but pants for plaster. If plaster becomes wet at some point after curing, the meter will lead to false positives years after the wall has dried out (something to do with the salts in the plaster). I binned my meter.