1 May 2008
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West Midlands
United Kingdom
Our 3 bed bungalow was built in 1985. Exterior walls are brick on concrete foundations and the internal walls are breezeblock on concrete slab. We have clay soil and a oak tree 12m from the point of the closest wall crack. All our cracks are on internal walls (not loadbearing) and the 3 which are the worst we have taken pictures of.
Bedroom 2 This crack started 20 years ago, was polyfilled 15 years ago, and then left as the room is unused, it runs up corner from skirting board but doesnt quite reach coving, it is 2mm at its widest point. However the crack has gone through the wall into our main bedroom. We polyfilled our bedroom wall crack 2 years ago but it showed as a hairline crack again after 12months.
Bedroom 3This crack has been evident for some 10 years, has got progressively worse runs from skirting to 1ft below coving, is at its worst around radiator approx 1.5mm wide, it is now showing as hairline crack otherside of wall in our lounge.
The hall crack is 2mm at skirting travels up wall and then splinters off into 2 hairline cracks across wall and also upto coving.
As they are internal wall cracks (we have checked and have no external wall cracks) how do we fix them to stop them coming back. We have always just painted our walls and do not want to paper over. However we do not want to keep having to fill cracks up. Possible causes would be appreciated, along with suggestions for repair. Many thank
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If these are internal partition walls built off the floor slab, then the two most likely causes are that the slab has dropped or is inadequately supported by proper foundations, or (and?) shrinkage due to different room temperatures and use.

Before doing a repair you have to treat the cause, or at least be sure that the movement is not continuing too much

If the the cause is shrinkage or the slab, and its not moving significantly, then a repair with stainless steel helical bars inserted into the wall joints is the best option and will work.

There may be several other possible causes, and you should get the property looked at by a suitably qualified person (structural engineer, surveyor), who will take into account all the possibilities, identify the cause, and devise a suitable repair should get the property looked at by a suitably qualified person (structural engineer, surveyor)...
Very few of the latter are suitably qualified to deal with subsidence issues; most run a mile when they see diagonal or stepped cracks and say you need an SE's report. If you want a definitive answer, get an SE to look into it.

Point to note: floor slab settlement/movement is not generally covered by household subsidence policies, unless main structure is damaged by the same cause at the same time.
The thing is for the OP to ask whoever they phone up "I have some cracked walls, can you survey and tell me what is wrong and devise a suitable repair, and how much will you charge me?"

This will be "the instruction".

They OP could also ask what other if any costs and investigations may be required (soil tests, drain surveys, trial holes etc) as even an engineer will most likely want these doing if the ground or external factors are suspect

Surveying practices may have suitably qualified persons, and there may even be a token engineer in there too!
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He wouldn't be much of an engineer, if he was employed by a surveying practice. Oh the shame of it... :LOL:
lol ..... alternatively he could be "living the dream"

Thanks for info but I am a little confused, whom should I ask for an assessment of the problem, I guess SE means structural engineer? This is all sounding very expensive, granted we have internal wall cracks but we have no evidence of any floor movement internally. All doors open/close without any problems. One factor seems that the cracks are either close to radiators or bedroom 3 wall is back wall to open chimney which we use regularly. The cracks have not just appeared bedroom 2 has been around 15 yrs, but we have had some other minor ones appearing in the last 3-5 years. The word subsidence frightens me, I gather that once you register this with your insurance company your house valuations plummets - even when you have had the repair carried out with the approval of a structural engineer. As long as the cost is not horrendous then we would prefer to go ahead ourselves and not get the insurance company involved. Has anyone any ideas of what we may be looking at cost wise?
..... but we have no evidence of any floor movement internally.

Yes you do - the cracks in the walls!

I blame that naughty engineer for mentioning the 's' word. The floor slab can go just a touch due to normal movement or poor design, and it may have nothing at all to do with subsidence :rolleyes:

There are lots of possibilities for the cause of the cracks, and unless you are able to diagnose these yourself, then its no good surmising.

Pay a few hundred pounds and get it looked at, and the cause diagnosed.

Once you have this information, then either sort the repair out yourself, or claim on any insurance if the risk is covered.

It does not matter if you go through the insurance or try and keep it quiet. One of the questions I ask on a survey (and the solicitor and buyer should ask too) is "Have you had, or do you know of, any structural repair to the property, or similar work more than just basic DIY work" and the owner must answer this truthfully
The house is 23 years old. Repaired cracks in internal walls that continue reopening after that length of time suggest something more than settlement of the sub-base material is going on.

Unfortunately, without an invasive investigation, you are not going to get a definitive answer. Consequently, just repairing the cracks may subsequently prove to be futile.
Thanks for info so far, all seems like bad news. Have found someone who is a Chartered survey engineer, is this OK, not certain what chartered means.
Have found someone who is a Chartered survey engineer, is this OK, not certain what chartered means.
Think you mean Chartered Structural Engineer. If so, that's what you need. More info.

Chartered = God btw :). But not for surveyors, of course ;)

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