Major Damp problem

[djkeates]

Hello all I have a major damp problem in my bungalow, I have noticed things leaning aginst the wall appear damp, some have green mould on. The area next to my skirting board is damp to touch also wall paper is peeling off just above the skirting. This is the same on everywall of my property. We have gas central heating which is on at least 5 hours a day, so the place is heated properly. the only thing thing I notice is the external rendering goes right down to the ground (you can see no damp course) Could this be the problem?? I have only lived at this property a short while and have only just noticed the problem.

Any suggestions or comments would be most welcome

Thanks Dave

[keith_765]

Get the rendering cut off about 300mm above ground level and a DPC injection system put in.This will probably have to be done inside as well.

[Andrew Gabriel]

Is this only at floor level, or how high up?

I suspect your walls are not insulated, so when you put something against the wall, that something effectively forms the insulation. This means the wall behind gets cold and condensation forms.

However, more info required.

[david.cawkwell]

If your internal walls are damp free then most likely the damp proof course is ok. If you have render on the outside then this should be above the damp proof course and you should be able to see the damp proof course. If not chip away at the render and see if you can find it. Remove any render below the damp proof course. Allow things to dry out perhaps this could take a couple of months at this time of year and take another look for damp.

If only parts of walls are affected then I used a damp proof injection chemical it comes with an applicator gun available at most hire shops. You drill a hole between the bricks and inject in. The chemical is then spread out by the damp and makes a new seal. Works well and cured the problem on two problem corners in my house.

[Robert Laws]

Is it condensation? Is there adequate ventilation, especially in the kitchen? Robert

[TheScullster]

"djkeates" wrote

Also worth considering leaking pipes. Do you have solid floor or suspended wood? If you turn off all water users, do you still hear water flowing in pipes or see water entering storage tanks?

Phil

[Stuart Noble]

As it's rendered, one option would be to paint the outside with a pliolite paint available from trade outlets like Johnstone's etc. If water is getting through the render, that should stop it (where ordinary masonry paint won't). Not cheap materials wise but worth a try before more labour intensive solutions

[Phil L]

Your own suggestion hit the nail on the head, you need look no further than the external rendering - it needs to be sliced off at least 150mm above DPC level - this is usually the level of your floors inside. Take a tape measure, a marker pen and a spirit level and draw a line at

150mm above DPC, then get an angle grinder and cut a straight line into the render - this is made easier if you affix a batten to the wall and whizz out on top of it, so that the blade makes a straight cut - it should then be a simple job of removing the render below the line. There's also a possiblity that there is no DPC, this will be apparent after the render has been removed, although simply removing the render will probably relieve the problem regardless of whether there is a DPC or not.

[tomhoban]

Rising damp generally only affects the wall up to about 3 feet or a mitre high. A chemical injected DPC would be the cheapest and quickest option, if it is in fact rising damp, but it sounds like a condensation issue if you can feel moisture on the internal walls, in which case you might consider hiring a dehumidifier, and increasing air supply to the property, you can hire one from most local hire centres, and if it makes an improvement, you can buy one for future use, if it is a bridged or defective dpc problem, then you can hire an injection machine and drill from most hire centres and get the dpc fluid from Wickes or other building suppliers, you can also get a couple of free estimates from local remedial damp proof companies for some free expert advice

regards chippyboy

[meow2222]

The best thing would be to ask people that understand the subject

[Maris]

What is the internal plaster like? Is it hard render? Does the mould increase towards the corners? If the answer is 'yes' to the last 2 questions then you have a condensation problem. My brutal solution would be to strip the render and reinstate in lightweight plaster of some sort.

Maris