Where to even start! Damp everywhere, recommendations please

[davidmit]

Hi All, appologies as I did not expect to see so many people with damp problems on this forum. So this may be just adding to the list. But I am looking for recommendations who to get in to fix my damp problems ideally one person for all of them.

A quick history, is that we have lived in the house a little over a year, its a 1947 (so built just after the war when bits were scarce), and has recently been cavity wall insulated (Bad idea in hindsight).

When we moved in to get the house liveable we spent alot of time and money getting plastering, floors painting done, but now are realising there are funamental problems causing damp plaster and flaking paint EVERYWHERE. So really need to get these fixed before getting the next rooms done.

My problem is that we are seeing serious damp problems, with each job looking expensive, so we need to get things priced up to get them sorted, but don't know who to ask.

There are 3 main problem areas:

Window frames:

Should a window frame have flashing or something simular? You can see on the pic of a room that hasnt been plastered, that its just window frame on brick.

Looks like its sealed ok from the outside, but is getting quite wet when it rains.

Outside

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• davidmit
• 16 Feb 2014
• 1

Inside result

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• davidmit
• 16 Feb 2014
• 1

Should it be like this, different room without plaster?

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• davidmit
• 16 Feb 2014
• 1

Should there be some type of flashing between windowframe and brick?

This is happening on 9/10 windows in the house, so what are my options here?


Problem 2, Living room extension:
Next problem is that in the living room, there is a small extension with a flat roof and I believe a single skin wall, and water is penetrating where the new wall is build onto the house, can I get some type of membrane for the outside of the wall??:

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• davidmit
• 16 Feb 2014
• 1

Causing this mess:

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• davidmit
• 16 Feb 2014
• 1

Options? I was quoted £12000 to rerender the house, but dont think this will solve much other than maybe this Joining wall problem, which is expensive. If it will fix this and the window problem, then is worth swallowing the cost and looking into.

Final problem, Chimney, has an external stack, pots are not cracked and render on chimney at top is ok, and I have painted on water proof breathable paint, but when it rains I still see water coming down the chimney, comes down onto the hearth, and hence I get damp walls both upstairs in the bedroom above and where it runs down the lintel downstairs, this looks terrible:

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• davidmit
• 16 Feb 2014
• 1

Each one of these are big problems on there own, I need to get them all sorted but could use advice as to who to get. A general builder? Damp specialist? Window fitter? I had a damp 'expert' tell me to seal the inside wall with a membrane to fix fireplace (which would just hide the problem surely).

Do I need all new windows? Or just take windows out, get flashing on there and reinstall?

I live in the South West (Forest of dean) in case anyone can recommend somebody. specific?

Sorry for the ramble, I can take more pics if needed.

 

[Flyboytim]

(Re-)rendering is possibly not the answer.

If the house was built with permeable bricks, a lime mortar, and has been surfaced with an impermeable render (inside and/or outside), and has a filled blown particle cavity wall insulation, and gypsum plaster, especially if painted with a vinyl or wallpapered on the surface, or has plasterboard reveals around uPVC windows, there are probably signs of damp already.

Just like it has been impossible to dry washing outdoors over the last two months, your house is struggling to breathe out the moisture it has absorbed.

Another similarity is wearing a waterproof jacket for too long - even if it is no longer raining, the jacket starts to get wet on the inside, as body moisture condenses on the inside of the waterproof layer. To remain comfortable, the garment needs to be breathable.

Damp companies will push unnecessary injected damp courses, additional rendering, more insulation, replastering and tanking to relieve you of your money. At the same time, these measures will not address the true cause of damp, which is the inability of the structure to breathe under the extra layers of impermeable and moisture trapping insulation.

//www.diynot.com/wiki/Plastering-and-Rendering:index

Have a good look at the links in the Damp and Condensation... Managing Damp... ...Condensation... sections - they may give some answers

From the pictures in the original post:

The windows have voids around them since installation, which are as cold as the outside, and warm air from inside has condensed its load of moisture on these cold surfaces - there may also be rain forced in during the storms.

The chimney possibly needs a cowl to keep out driven rain, and/or a fire to keep the flue warm and dry.

Roughcast rendering - how much of this was original, or additional or repaired?

Was the original a breathable lime mix, with a breathable finish, or has it always been a hard cement, or just overpainted with a modern, impervious masonry paint.

Air movement is vital to make sure areas prone to or suffering from damp get to the same ambient temperature as the internal air - condensation will not then occur, and the plaster will dry. Ordinary desk fans will move air and dry out windows, corners, behind furniture, in cupboards etc. If anything, do not use extra heat, but do not allow the house to get cold at night or when everyone is out instead thermostat to a cool temperature, say 15C, and only raise the heat to comfort levels of 18C when people are about and relaxing.

Whatever remedies you decide on, get them booked in for September to give the best chance of drying out.

 

[davidmit]

Thanks for the reply Flyboy.

I painted the walls with a breathable masonary paint that came well recommended on the web, so hopefully that is not causing the problem.

I did have cavity wall insulation (without doing homework into the problems), and I worry that this may be a big cause of the problem, with water getting in and being stored in the insulation. Kind of stuck with it now!

I'd be surprised if my problems were due to condensation, as it all seems VERY damp, i'd hope condensation wasnt this bad.

Would you recommend simply asking a general builder to come and give an opinion?

I have looked at the herritage-house link a few months ago, and it has good information. But the guys are too far from me to come and take a look at the job sadly.

 

[Flyboytim]

The acid test is to drill into the middle of an internal brick in the damp area - if dust comes out, the brick is dry, if steaming sludge is present then the brick is saturated. If It is just the plaster, then it will dry as the humidity drops. If you drill the internal mortar, is it lime-based or cement, either hard biscuit-like or rock hard? Dry or wet. If you expose small area s of the underlying masonry in your problem areas, or just make small drill holes, you will have an indication of how dry the underlying wall really is.

Condensation is the most likely cause of your varied problems. Cold bridges cause damp spots, and the damp itself evaporates, creating a greater cold area which attracts more damp. It can build up fast.

Penetrating damp has obvious causes - roof problems, guttering, overflows, leaks, masonry defects. Areas which have these problems historically are likely to have repeated repairs.

A human exhales something like half a litre and sweats another half litre a day. Cooking and kettles, washing up, surface cleaning, showers, damp outdoor clothes, any drying of washing not in a vented dryer plus opening doors and windows and draughts letting in cold saturated outside air can literally put several litres of air into the house during each day. I have a husky and a collie who have a daily walk, mostly in the rain Damp dogs have an amazing capacity in their fur. Houseplants also transpire.

Saturated water content of air is about 10g/cubic metre at 10 C and roughly doubles for every 10 C raise in temperature. If you keep your house very warm, then turn the heating off, then the cycling of temperature between say 24 C and 14 C can cause half of the water content to condense out, up to 12g /cubic metre. This will concentrate on the colder spots, where there is likely damp already.

If your minimum temperature is raised, and your maximum is lowered, you will minimise condensation. If you equalise wall and room air temperatures, you can eliminate condensation, and your rooms will feel warmer than if there are active cold condensing surfaces causing pooling of chilled air near the floor.

I have to say that the paint is probably the least of your current problems.
What paint was under the masonry paint you used? (the Heritage House people seem to have no faith in any modern plastic-based paint whatsoever). I have no affiliation with anyone but having used good quality masonry paints in the past myself, I can see how they could be pretty impermeable after a coat or two over the years. It is also easy to see rendered, painted surfaces with entry points for water especially on angles and joints with other masonry, metalwork and woodwork.

You may need to seek independent advice regarding the cavity wall insulation, perhaps from your local council, CAB, or insurance company.

There may be a local tradesman to you that deals with conservation renovation that the council's conservation officer can put you in touch with.

 

[Guitar_man]

Some good comments from Tim regarding the breathing of the house. I guess you sre stuck getween a rock and a hard place. Personally I'd fix the chimney first as you have said you are getting water ingress.
I have a similar problem with an extension and a leaking cement bellcast (which I hope is the cause of my water ingress). Water ingress can do serious damage if left unchecked. My bellcast was ripped off today's, only to find wet bricks. Not good!

 

[davidmit]

What's the general view of getting an independant damp proofing company in to survey. Although I guess they won't be climbing on the roof to check the chimney caps etc?

Do you get people who guarentee to fix the problems or they give the money back etc? Or am I dreaming.

 

[ree]

An Independent Damp Surveyor near you is G.R.Coleman of Remedial Tech Services 01747 840 715.
He wrote the book "Guide to Identifying Dampness in Buildings".

 

[Flyboytim]

Damp proofing companies want to sell you a product or service! In what sense do you think they can be independent? I think you may be dreaming!

http://www.buildingpreservation.com/ is a link for the company ree referred to