Kitchen/Shed extension problem

[rigby44]

Hi all,

Recently moved into a house, 1930’s with solid walls. The kitchen has been extended (on the cheap I think) into what used to be a shed. It seems the insulation is slim to none as its always freezing, condensation on the walls and black mould when you move the kickboards. Put a dehumidifier in there, showing 80-90% RH and wont go below 70% even with the thing running for hours. Goes straight back up once the dehu is switched off.

Also getting slugs overnight as presumably they like the damp conditions.

Feel a bit desperate! Paid for a building survey pre-sale and no mention of any problems.

Thanks
Ian

 

[rigby44]

Hi all,

Recently moved into a house, 1930’s with solid walls. The kitchen has been extended (on the cheap I think) into what used to be a shed. It seems the insulation is slim to none as its always freezing, condensation on the walls and black mould when you move the kickboards. Put a dehumidifier in there, showing 80-90% RH and wont go below 70% even with the thing running for hours. Goes straight back up once the dehu is switched off.

Also getting slugs overnight as presumably they like the damp conditions.

Feel a bit desperate! Paid for a building survey pre-sale and no mention of any problems.

Thanks
Ian

 

[Notch7]

Do you mean a single skin brick outhouse, rather than an actual shed?

 

[rigby44]

Do you mean a single skin brick outhouse, rather than an actual shed?

Apologies. Yes, I think thats a better description. Single skin brick outhouse.

 

[Old Salt]

Dehumidifiers don't appear to work really well when its cold.

 

[JohnD]

You mention a kitchen, which presumably has a sink, drains, taps and water pipes.

What do you think is the source of the water causing the excess humidity and damp?

 

[sxturbo]

i imagine they didnt do the conversion of the outhouse wall very well,

what needs to be done is to remove the kitchen and insulate the walls, this can be done relatively cheaply with celotex, battens, and plasterboard,

but also pay attention to the flooring, and the DPC of the out house to make sure, a) its there, and b) they haven't bridged it to bring the floor up (is it wooden or concrete floor?)

 

[rigby44]

Dehumidifiers don't appear to work really well when its cold.

Bit annoyed with the one I bought. Advertised as fine down to 5 celcius, but puts itself into ‘defrost mode’ at 10 degrees or more.

Very sceptical that these things only cost approx. 5p/hour to run too.

 

[big-all]

5p an hour is only about 350w perhaps you need a more powerful machine in the short term to help before a proper solution is found

 

[JohnD]

Is the floor damp?

This will show if you lay something impervious, such as a plastic mat, on it, and water collects underneath.

Some photos would be informative.

Damp is water, so it will be coming from the ground, or boiling kettles, or a leak in plumbing, drains or roof.

Have you got a water meter?

 

[Old Salt]

Bit annoyed with the one I bought. Advertised as fine down to 5 celcius, but puts itself into ‘defrost mode’ at 10 degrees or more.

Very sceptical that these things only cost approx. 5p/hour to run too.

If you can get some heat in there they will pull the moisture out. Got mine from screwfix. Pulls 4 litres out overnight when its warm to preserve my classic car and “dry” the motorhome.

https://www.screwfix.com/p/blyss-wdh-122e-12ltr-dehumidifier/494gy