Damp ??

[JimM]

Hi all

I need some advise on what I think maybe rising damp in my kitchen ?

When we refitted the kitchen, I noticed that along the bottom of one wall the tiles came off very easily and the plasterboard underneath was mouldy. I know I should have taken action at the time but I hoped that if I just replastered and painted, the wall would be able to breath and dry out. One year later and the paint along that wall is bubbling and flaky so my optimism was a bit misplaced.

The wall in question is was what once was the outside wall but is now an interior wall due to an extension (extension was done at least 20 years ago) It's only 3' long and the flaky paintwork doesn't go above 6" in height but is along most of the length. It's a cavity brick wall, the other side of which is showing no signs of any problems. Floor is concrete with tiles. The house does have a DPC but I have no idea if this was touched/breached when the extension was done.

Any advice on the best way to tackle the problem would be most appreciated.

Thanks

Jim

[NT]

scraping what you can off and repaint it with a porous paint might be all you need do. Builder's lime makes an adequate white paint for this.

NT

[Cash]

Jim,

Before giving any advice on tackling the problem, a question first - is the plasterboard touching the tiled floor or screed?

Cash

[dom]

Could there be a leaking pipe embedded in the wall or floor around that area?

[stuart noble]

If the tiled wall has no heat source nearby, I'd suspect condensation running down the tiles. Wipe the lower part with a kitchen towel in the late evening and see how wet it is. If the situation improves mid summer, I'd say that was conclusive. If not, at least it's the easiest cause to identify/rule out.

[JimK]

always hard to visualise these (any chance of some pics somewhere?) but here goes:- this 3' of wall that used to be external (until extension added) is the rest of the wall still external and still connected to it? If so is there a vertical DPC? how to check is obvious prob....

Background --- A house I did had a standard ex-LA "side entry type" design that had been bricked across and a door and window installed by previous owners.... the remnants of what were previously *external* wall corners were always prone to damp and mould so when I did it up (installed some french windows). During that process I discovered there was no vertical DPC down each side of the opening - as the brickwork returned to the (now) inside of the opening there was no break so moisture "tracked" inwards and I am convinced had caused the damp, flaky paint etc just as you describe. The remedy for me was - before installing the new french windows, to cut with a stihl saw a slot from top to bottom of each side of the opening and insert DPC membrane - worked fine & problem solved.:>))

Cheers JimK

[JimM]

Hi guys

Thanks for the responses

Just to answer a couple of questions,

There's no longer any plasterboard on the wall in question, when the kitchen was done I stripped it off and had it replastered and then painted.

A pic of the wall can be seen here

damp spreads along the wall into the dining room, although the yellow paint isn't flaking but the corner beading is presumably rusting as there are patches of this coming through the paint.

Cheers

Jim

[JimK]

righto thanks for pic...

So is the kitchen the extension? or was where you stood to take the pic the extension?

Can you tell (praps by refernce to neighbours houses?) how the building would have been arranged originally? (to give a clue as to what this wall was exactly and how it would have been constructed).

I'm wondering if that bit of flaky wall visible and into yellow (dining?) room is/was the outside leaf of a cavity wall and the new floor has bridged the DPC...

Cheers JimK

[JimM]

Hi Jim

Thanks for your input

Where I took the photo is the extension, the wall with paint issues and the part you can see that is painted yellow would originally have been the outside face of the rear of the house. The extension runs the full width of the back of the house so in effect it extended the kitchen and dining room. The rest of the exterior walls of the house are cavity walls with breeze block inner and brick outer, so would assume this wall to be the same.

Looking at the neighbours house the DPC is only 1 brick course up and the door frame is directly on this, so the floor would appear to have been very close to the DPC originally (no idea if this is normal ?) The flooring in the kitchen runs very smoothly the full length but in the dining area there is a noticeable bump in the floor at the point where it goes from old to new. If the DPC has been bridged is there an easy way to tell without ripping up the floors :( or is there a DIY solution that I can try and see if that fixes the issue

Many Thanks

Jim

[JimK]

Hi Jim, when you say ... " Looking at the neighbours house the DPC is only 1 brick course up and the

..1 brick course up from what? the ground or something else?

so in the photo - are we looking (left hand side) at what used to be an external doorway (and still is on the neighbours) thru to your present kitchen area?

as far as solutions - I reckon you'd be best first trying to mask the issue and see if you can live with it..solving it "properly" could end up being a messy and expensive can-o'worms...

Are the walls (white and yellow) still plasterboard or trad. plaster? is it actually "wet" or just flaky paint?

If the latter i.e. "cosmetic" I would be tempted to hack off the skirting boards and 18" or so of the manky plasterboard- see what its like behind - is the pboard on battens or dot and dabbed?

If not too grim behind existing I would look to replace with foil back plasterboard - fixing it with adhesive lower down (gripfill or similar) so avoiding puncturing the foil. At the external corner, before fixing beading with more gripfill I'd look to seal the cut edges of the pboard, at least lower down, with some water resistant sealant - one of those MS polymers that stick to anything would be my choice to try and maintain the damp barrier.

Leave a gap between the pboard and the floor (18mm say) hide that with new skirts (if old are manky) but glue 'em on (after painting the back and bottom edges with gloss to resist any damp).

Any good?

Cheers JimK

[JimK]

Hi again

re - > ..1 brick course up from what? the ground or something else?

Yes, 1 brick up from the ground

I'm happy to 'live with it' if it's not going to cause any major problems. The fact that it's probably been like this since the extension was done but was hidden behind the tiles for the last 20 years gives me some comfort that it's not too serious.

The plasterboard was removed when refitting the kitchen, not sure why it was there anyway as the house has plastered walls, I think it was just slapped up to give a level surface to tile on during a previous refit. After stripping the board off I got a plasterer in to patch and skim the whole kitchen.

The walls aren't damp to the touch, the plaster itself looks as good as it does anywhere else.

I can see the logic in your advice in trying to create a barrier between the floor and the finish surface of the wall would this still apply with the plastered wall. Ie should I hack off the bottom 18" of plaster and then apply some sort of waterproofer to the brickwork (PVA ?) before replastering. Would it help if I used a lime plaster (assuming this gives a finish surface)

Thanks again for your help

Jim

[JimK]

from the sound of it I'd agree that it just needs hiding and mild finger crossing :>)

OK in that case how about :- take the skirts off, paint with Thompsons Damp Seal paint upto about 12" from floor, refit skirts (or replace if manky) using gripfill, paint it all up and see what happens??

My scheming was to try to seperate the finish surfaces of the walls from the dampish wall structure behind as well as the floor below - whats the covering on the floor in the dining room?

BUT as it's not "wet" I'd give the damp seal bodge (above) a go first

- it's cheap, quick, easy and may do what you want. If it doesn't come back and have another consult on here?

Cheers JimK

[JimM]

Hi Jim

The Damp Seal paint sounds ideal and I see Screwfix stock it, I'll pick some up tomorrow and hopefully that will sort me out

Thanks once again for your help, it's much appreciated

Cheers

Jim