Cracks which reappear......

by **gillybean** » Mon Dec 27, 2010 4:47 pm

Hope someone out there can put my mind at rest.
Lived in 1930's semi for around 10 years. The small kitchen always had hairline cracks on the ceiling and above the door, no external cracking. I hoped the extention would cure the problem when most of this external wall was removed. In 2007 we had a wrap around extension built. On inserting the RSJ a lot of the upper wall moved needing some of the landing to be replastered. Since then in the extension where old joins new we get hairline cracking along the rsj plasterwork, each time it's filled it reappears. There are also cracks where the wall meets the ceiling. Upstairs we have hairline cracks in the bathroom, this was boarded and skimmed in 2002 and these cracks reappear. Then we have cracks along the staircase where the wall meets the skirting also same problem on the landing and around one door architrave, I hope this is because of differing materials and shrinkage maybe? Instead of filling I have taken photos for the last 3 months but there isn't any change. The cracks reappeared this year Autumn time, might mention we have a large council tree about 10m from the house and it's built on clay, a recipe for disaster, so many sleepless nights. Our survey 10 years ago revealed nothing alarming however it was deemed unsuitable and we had to make a claim as the surveyor didn't spot basics like a rewire or damp so I can't rely on that, any help appreciated.

by **gillybean** » Thu Dec 30, 2010 4:33 pm

anybody out there?

by **welsh brickie** » Fri Dec 31, 2010 10:50 am

I would have a structural surveyor check for you,Its the only way your going to get peace of mind,Personally I dont think its a major problem by what your describing.

by **tidy** » Fri Dec 31, 2010 9:33 pm

the cracks in the plasterboard is the slight movement in the timber as this sometimes will give you hairline cracks.and again where ceiling meets the wall.
without looking at it i would say you have nothing to worry about.
you could put coving up.this of course wont stop the cracks but will hide them.and give you a better corner on wall and ceiling.
when plastering up against old plaster you should coat old plaster at the joint with building adhesive as to seal and give a better fix but if you have a wood under this then it is better to put a wire mess on first.

by **gillybean** » Sat Jan 01, 2011 8:16 pm

Thank you for your responses.

I am trying to avoid getting a report, mainly for the cost implications, I wouldn't think you'd get much change out of £500.

I think the Victorians had he right idea with their coving and thick lincrusta wallpaper!

Style of kitchen doesn't lend to coving, particularly as it's vaulted at one side of the room, I think at some point we will place beading/angle bead edging down the side of the staircase as every time I go up it drives me crazy. I will continue to monitor the cracks and won't fill until I am happy there's no movement. I am sure they open and close and this is I feel sure connected to the large tree I mentioned, the council are happy with it but I just think in the last 70 years it's bound to have grown loads and have a detrimental effect on our clay foundations due to shrinkage and swelling through the year.......

by **gillybean** » Sat Jan 15, 2011 1:35 pm

Seems that hundreds are viewing this site but hardly anyone helps/replies, wonder why that is.....

Does anyone out there have an idea how much a structural engineers/surveyors report is?

by **tidy** » Sun Jan 16, 2011 11:48 pm

gillybean wrote:Seems that hundreds are viewing this site but hardly anyone helps/replies, wonder why that is.....

Does anyone out there have an idea how much a structural engineers/surveyors report is?

if it was the tree the cracks would not be opening and closing plus would over time get bigger.
get in touch with your council building regs and have a word with them they can send an inspector round as far as getting a structural engineers report i think you are probably waisting your money but then if it puts your mind at rest then go for it.

by **gillybean** » Tue Jan 18, 2011 4:18 pm

Hi Tidy

Thanks for your reply!

I assumed it would be the tree taking moisture from the clay soil then as it rehydrates the cracks close?

Getting an inspector....I doubt that they would come out, I had all on getting them here when I paid for building regs 3 years ago, and then they came when I wasn't in!

by **chris_on_tour2002** » Sat Jan 22, 2011 12:42 am

Benjamin Franklin said: "'In this world nothing can be said to be certain, except death and taxes."

he should have added "and household cracks!"

there are posts galore all over this site on this very subject, in fact an entire website could be dedicated to such a forum.

most cracks, whilst highly annoying, are usuall benign. you have a 1930s house built on clay to which you've added new parts. they are bound to be settling at different rates and the result is the visual manifestation of cracks. you say that you thought that the extension would cure the problem - i hate to inform you that actually the reverse is true!

based on your description (by all means post some photos if you'd like a more in depth analysis) i'd say that you've nothing to worry about. it all sounds quite typical of the cracking that can appear after an extension has been built.

cracks around the join between old an new, cracks where ceiling meets wall, around door architraves etc all sounds typical. and hairline cracks are usually completely inert.

unfortunately no amount of refilling and painting is going to cure it. they will just reappear.

factors such as temperature and humidity, amount of rainfall etc can all have an effect which could be why they seem to reappear in august.

i doubt that it's anything to do with the tree - as tidy has said you would expect the cracks to get bigger and also to be running vertically up the walls etc.

if you really want peace of mind then hire the services of a structural engineer - a few calcs and a look at the drawings shouldn't cost any more than about £300, depending of course on what they find. but it may be worth it for your peace of mind.

there is a chance in fact that they may not even charge you - or a minimal call-out charge if they turn up and it seems obvious that all movement is normal and indeed anticipated.

BTW - if, perchance, the tree does get remove make sure they DON'T poison the stump. my father-in-law had a council tree removed just 8 feet from his front door (very small front garden, London town house) and they poisoned the stump to kill it off - roots went into spasm and contracted in shock leaving big voids beneath the house - three months work and tens of thousand of pounds insurance claim for underpinning later and they finally have their house back.

by **gillybean** » Sat Jan 22, 2011 7:09 pm

Hi Chris, thank you so much for your reply. I am beginning to get paranoid about the cracks, I have of course googled pics and other items re subsidence and have become a bit obsessed of late which isn't good you're right there are loads of houses with unexplained cracks.

Thanks for your thorough response. I really feel for your Father in law, and it made me think.....we actually removed part of a sycamore tree, I say part as the previous owners had tried to remove half of it, we bored holes in the stump and now it's well and truly dead, this would have been around 10 years or so though, now you mention it I wonder if this contributed to the cracks before the extension was built?

I thought that trees contributed to subsidence, is this a myth?

Other houses I've had haven't had this problem, and now I know these damned cracks are there I am constantly looking at them, it drives me mad! We have even used 'flexible' filler and they still crack along the stairs.

I'd love to post photos (oh, yes I have lots!) but am unsure how, I'll look into this....

by **gillybean** » Sat Jan 22, 2011 7:32 pm

Hope this works!

[/url]http://s1114.photobucket.com/home/gillybean129/index

by **chris_on_tour2002** » Sun Jan 23, 2011 12:36 am

i've had a look at the pics, the technology works :)

from what you've shown in the pics (of course i have to include the usual caveat that the opinion i give is without proper sight) i still say that you have absolutely nothing to worry about.

i didn't mention in my previous post but i live in a 1930s built house also on clay. though we've never had an extension built i did remove a structural wall last year and put in an RSJ to convert the kitchen and dining room into one open space.

the pattern of cracking in our house is virtually identical to that of yours. and i know that many (if not all) the houses in our street are the same. (i have friendly neighbours) i'm not in the least bit concerned about the structural integrity of my house.

incidentally i had a structural engineer round prior to commencement of work to do the calcs and approve the work in principle, and the local building control have signed it all off post event. in fact the gentleman that gave the final sign off was quite complimentary about the standard of the work and it's not easy to get a compliment out of them! nonetheless i have cracks. i can live with them, the wife moans endlessly but frankly i am not prepared to waste my life repairing them with utter futility.

nothing you can do about them i'm afraid. if i could offer a quick and permanent solution i wouldn't divulge it here! i'd be on dragon's den in the first instance then i'd be off to live the dream. the best advice i can give is to forget about them for a couple of years, let everything settle some more then try and address the problem again.

my only mild concern, i can't quite make out what is going on in pic 4? what is the white frame beneath the crack? it looks to me like the site of the new RSJ. in which case the boxing in (plasterboard normally) has separated slightly from the surrounding masonry. again, it looks alarming but is pretty typical.

but seriously, if you've shown the worst of the cracks in the photos then the best thing that you can do is learn to live with them and stop worrying about them.

get an engineer round for peace of mind if you want but i'm sure that he/she will just confirm the same.

with regard to the tree - certainly no myth that they can cause subsidence. instinctively i didn't think that the tree was responsible in your case based on your description. based on the photos i would still maintain that.

one key piece of info that you omitted, what type of tree is it? this will determine the root system, how far they spread out and the girth etc which all affect the level of potential disturbance to a nearby structure.

i have a cherry tree less than 3 metres from my kitchen window. it's causing no problems at the moment but sadly it's days are numbered for the exact reasons that you have highlighted. if it gets much bigger it will start to undermine the foundations of my house.

and as regards the sycamore that you refer to - if the tree wasn't poisoned and the tree is dead then the roots (which are pretty dense) will very slowly decompose and turn to earth. far less chance of leaving voids as they retract so slowly that any void will be naturally filled by the surrounding soil and the rotting root itself. the point i was making is that a poisoned root system will rapidly tense up and shrivel to leave a void.

my bigger concern is what you did with the tree once it had died! if you have a mature full grown dead sycamore nearby you need professionals to get rid of it! it represents a real danger.

footnote: don't feel too sorry for my father in law! he got his whole house renovated and underpinned by his insurance company. 3 months of upheaval well worth it now!

by **gillybean** » Sun Jan 23, 2011 2:01 pm

Hey Chris, thank you so much for taking the time to look and reply, I feel a lot better now :)

First the trees, the sycamore had been lopped, it was just the trunk no foliage which remained, it was around 9 feet tall. The guy who removed it took it away to be shredded or chopped or whatever tree people do with them! It just looked ridiculous as it was in the centre of the hedge.

The council tree which is on the pavement has already cracked our boundary wall but the council maintain it's due to our small leylandii hedge, which I disagree with at they have fibrous roots don't they? Anyhow it's a large Ash tree. At the other end of the garden further away is a lime tree which I believe are very thirsty trees but seen as this is further away I'n not too concerned. When the houses were built I am sure they didn't give much consideration to what they planted back then, nowadays they would only plant ornamental trees, perhaps like your cherry which generally aren't as invasive I think. The council assessed the tree over 3 of years ago as I mentioned about the roots sometimes visible in the grass, they told us to just remove them ourselves! I wished it wasn't there, much as I love trees but by removing I have read it can cause 'heave' as long as they maintain it....

Back to the photos. Yes, photo 4 is the boxing in under the RSJ supporting what was the external wall, also inside is the waste pipe from the bathroom above the kitchen - lovely! You can see where underneath the plaster and paint are kind of flaking off. My fear is that the old and new foundations are of course different and that one is moving against the other, I would have expected any settlement from the extension to have stopped by now. The extension was checked at points by the inspector who always came when I wasn't in. It's our fault it didn't get the final signing off as the only thing we couldn't agree on was his insistence to install vents in our windows as it's really exposed where we are (regularly get wind up to 50mph). Other than that the architect working with us sorted the calcs for the RSJ.

The worst cracks are on the landing above where the wall was removed along the skirting, they drive me mad and they look real bad in the pics, the green paint (must change that) crack is just above the tiling is common in a lot of houses that are the same on the lane ( I asked!!) apparently it's a common fault it still worries me though.

Thanks Chris!

by **swords99** » Sun Feb 13, 2011 12:43 pm

The reason why the cracks keep reappearing after you fill them is because you are using a band-aid method. Just covering them up won't provide a long term solution. You need to find out why the crack(s) is there in the first place. Could be a settling or foundational problem. Some cracks appear during certain times of the year and then disappear as wood expands/contracts. If the problem is very serious, you may need to tear down and replace the drywall or plaster. If its foundational,, only a professional can fix this.

by **gillybean** » Mon Mar 07, 2011 7:21 pm

swords99 wrote:The reason why the cracks keep reappearing after you fill them is because you are using a band-aid method. Just covering them up won't provide a long term solution. You need to find out why the crack(s) is there in the first place. Could be a settling or foundational problem. Some cracks appear during certain times of the year and then disappear as wood expands/contracts. If the problem is very serious, you may need to tear down and replace the drywall or plaster. If its foundational,, only a professional can fix this.

So how do we find out if it's 'serious' or 'foundational' foundational sounds pretty serious to me......