Is my house cracking up?

Kashkai

As regular readers of this forum will know, I had a nightmare building process 3 years ago that I thought was resolved at the end thanks to the late intervention of an excellent engineer (who has since moved abroad thanks to the building sector decline). Hairline cracks did appear in the ceilings between the old house and the 1,600sq ft extension which I put down to settlement.

However these cracks (no more than 1mm wide in the worst crack in the ceiling), which I had previously filled, have reappeared and lengthened and now they are in the ceiling, walls and (most worringly of all) the floor tiles also have hairline cracks in the kitchen, which is the one room thats "shared" between the old build and the new extension. It appears to me that the new extension is pulling away from the old existing structure (which is crack free). Everywhere I look in the new extension, there are cracks where the ceilings meet the external walls (they were filled in previously with pollyfilla and later with "painters mate" but have split open again). The cracks in the walls are for the most part vertical in nature but there are 2 diagonal cracks coming from 2 doors. The new extension was built on a raft foundation to ensure that any settlement would be symmetrical but it appears not to have worked.

I have a tendency to think the worst of most problems but in this case I fear I do have subsidence. How do I go about trying to find out how much trouble I'm in? I can't decide whether to:
- get an engineer in
- contact a loss adjuster
- contact the insurance company
- contact my solicitor to go after the builder (if he's still in business)

Has anyone had similar problems in the past with their build and how was it rectified (cracks in the walls and ceilings I can fill in but the cracks in the floor tiles are worrying me the most). I have googled "Subsidence" and for the most part, I haven't the trouble that most people have where their houses have confirmed subsidence, i.e. large wide diagonal cracks, stuck doors and windows etc so am I over reacting?

Sounds like they may be shrinkage cracks, I have a few around the house as well - this cold weather makes them appear larger as the difference in humidity between the inside and outside of the house is quite large.

The heating is likely to be drying out the air, which is drying out the structure further - those last bits of construction moisture is finally coming out.

After the first full year in the house here, I filled in a couple of the worst cracks but the following year they opened up again! But most importantly they are not growing!!

I intend to fill them again in a couple of years and redecorate!

746watts

If your kitchen floor tiles are showing cracks, I think thats a major foundation or sub floor failure problem, with any build cracks in slab work can happen, but not the floor. Was the foundation a strip foundation? How deep & wide is it? Was the correct guage steel used and was it tied and overlapped to regulation? Was your kitchen sub floor gravel whacked down properly? Was there grid reinforcing steel put in the concrete floor? All these things if not done properly can lead to structural problems. Further movement may continue. I hope you get sorted.

haines35

The new extension was built on a raft foundation to ensure that any settlement would be symmetrical but it appears not to have worked.

Answers most of the above...
OP,where the tiles are cracking in the kitchen,i presume its a concrete floor?also is it at the joint of the old and new floor?

Kashkai

I thought (in one of my cheerier moments) that the cracks might be due to shrinkage as we have the heating blasting away (as we have a 2 week old baby to add to our other 4 kids) and we want to keep the place warm in the current cold snap. I have filled these cracks in in the past and painted over them but they have all reopened. In my previous 2 houses, which were also new builds, I never had cracks like these which is why I'm seriously concerned that there is a more serious problem.

The kitchen floor was dug up and replaced by the builder as "it was falling to bits" as he said. The real reason was that when he broke through to join the new extension to the existing build, the floor in the extension was higher and to get around this, he dug up the old floor (without getting my permission first) and then relaid a new one that sloped down to the rest of the house. The guy I got in to tile the kitchen floor was very annoyed trying to lay tiles on a sloping floor. So I don't know what he did to whack down the fill under this floor (I presume he never replaced the fill and just poured the new slab over the extension and existing floor) as the new slab was poured by the time I got out to the house.

To resubmit my original question, any ideas who I should contact to try to get answers as to how much trouble I'm in. The insurance company is my last resort cause if they hear I might have subsidence issues, they'll hammer me come renewal time.

haines35

1 mm cracks would not be a major concern to me and are most likely due to shrinkage this can occur for a long time after a build,the cracks in the floor may be over central heating pipes?this may cause a crack in the tiles.
You mention a bad leak under your floor in a previous post,this in itself would not help in the floor situation.
It is not unusual to see some hairline cracks at the corner joints of ceilings and walls again due to shrinkage and movement,easiest remedy is coving!!
I certainly would not be panicking about them but do keep an eye on them over a long period of time(6 months)take photos for your own reference to see if they get bigger and i would`nt rush to tell insurance companies etc..
oh and remember there was a crack in the queen mother and she lasted for nearly a hundred years;)

Kashkai

Like I said, I'm a worrier by nature and if you knew the type of eejit who built my extension, you'd become a worrier too.

The cracks across the ceiling are not my main concern, its the cracking of the floor tiles thats giving me most grief as they are cracking in 2 separate places. To my knowlege, there are no heating pipes in the areas concerned and the leak I mentioned in another post is in a different room. I checked my insurance policy and guess what, cracks in the floor slabs are not covered and thus if I have to go ripping out the wife's €25k kitchen, and digging up the kitchen floor to relay the slab, it'll be at my expense.

mossfort

if you have a raft foundation there might not have been enough steel rebars put in or it might not have been tied properly.
if a raft is done properly you shouldnt be getting cracks.
the ceiling cracks could be from the joisting not being properly bridged or no jointing tape being applied to joints in the slabs.
i would consider getting your engineer to have a look at it and he might point out what is wrong.
its sounds like you were unlucky in getting a cowboy builder so i hope you get it sorted.

gman2k

Dave, you could get yourself a few tell-tales and position them over the worst of the cracks and monitor them over a few months.
Just make sure they are away from prying hands :-)

bob10

Hi Dave

We have stumbled across your question because we too fear we have subsidence and also do not know how best to go about finding out. Does it need to be this complicated? Someone must have experience of actually dealing with their subsidence and the process of that, but we are having no luck finding that help. Should you find a way forward, we would be so grateful if you post it here. We will do the same.

RKQ

bob10 wrote: »

Someone must have experience of actually dealing with their subsidence and the process of that, but we are having no luck finding that help.

Contact 3 local Structural Engineers, get written quotes from each for a visual site inspection. IMO nobody here can answer your questions without seeing the extent of the cracks. You need professional advice based on a visual inspection of the works by a Structural Engineer.

Good luck.

onq

Problems may arise if you have two different foundation types supporting two different buildings [2-storey -vs- single] which foundations are neither bonded correctly nor separated by an expansion joint & are experiencing normal settlement over time.

Also AFAICR Part A requires foundations, not a raft.

Who designed this one for you?

ONQ.

Wyldwood

not sure how helpful this is to you but we had our then 20 year old house underpinned 4 years ago. Basically, a lot of cracks started to appear internally with just one crack externally from a window cill to ground, not particularly wide but long.
We got 3 different opinions on the problem from professionals, 1 engineer said ignore it, 2 others said it needed to be tackled. We went with majority opinion and had it done. €35,000 later and a major amount of dirt and upheaval we were told we were sorted for life.
Long story short, we still have new cracks appearing regularly and original ones that were repaired are reopening. Engineer who oversaw original underpinning says he doesn't know why.
Moral of story is get many different opinions as I think they go for the easy option often which is to do the underpinning "just in case".

Wyldwood

Wyldwood wrote: »

not sure how helpful this is to you but we had our then 20 year old house underpinned 4 years ago. Basically, a lot of cracks started to appear internally with just one crack externally from a window cill to ground, not particularly wide but long.
We got 3 different opinions on the problem from professionals, 1 engineer said ignore it, 2 others said it needed to be tackled. We went with majority opinion and had it done. €35,000 later and a major amount of dirt and upheaval we were told we were sorted for life.
Long story short, we still have new cracks appearing regularly and original ones that were repaired are reopening. Engineer who oversaw original underpinning says he doesn't know why.
Moral of story is get many different opinions as I think they go for the easy option often which is to do the underpinning "just in case".

Try to find an old map of the area, look at the osi website they have old maps of most areas.

It could be that previously there was something else on the site that's caused the ground to have different densities which will compress at different rates, causing the cracking.

I knew someone who's house was built over an old pond, the pond was filled in in the early 19th century and forgotton about. The house settled badly and needed major work doing, they only found out about the pond by looking at historic maps.

paddy147

Some people are are genius on paper but absolutely THICK as 2 planks in the real world.

John368

I am a chartered structural engineer, but not looking for work here I might add. I quite often look at houses to specifically advise or cracks. Often the cracks are not serious, but sometimes they are serious and remedial building works have to be carried out to make the property saleable.

A chartered engineer might be expensive but it is probably going to be worth it get some piece of mind. Most chartered structural or civil engineers do not advertise widely and get most of the work through architects so maybe that is a good place to start to look for one. Call into you local architect and ask him/her if they know a good engineer to look at the house. They will not usually mind as few architects want to get involved in structural matters like this and will be quite happy to pass the work on to an engineer.

Look for MIStructE or FIStructE after the engineer's name. (Member/fellow of the Institution of Structural Engineers). Or MIEI or FIEI (Member/fellow of the Institution of Engineers of Ireland) It is quite important that you get an engineer who has professional indemnity insurance. Few chartered engineers operate without it but there is no legal obligation for them to have it for them to hand out advice so it is up to you to check.

Sometimes the engineer cannot take on the job because he/she knows the builder or some other person involved in building and will decline the offer of taking on the job. If this happens do not get upset, he is just being professional and ensuring that there is not a conflict of interest.

bob10

Wyldwood wrote: »

not sure how helpful this is to you but we had our then 20 year old house underpinned 4 years ago. Basically, a lot of cracks started to appear internally with just one crack externally from a window cill to ground, not particularly wide but long.
We got 3 different opinions on the problem from professionals, 1 engineer said ignore it, 2 others said it needed to be tackled. We went with majority opinion and had it done. €35,000 later and a major amount of dirt and upheaval we were told we were sorted for life.
Long story short, we still have new cracks appearing regularly and original ones that were repaired are reopening. Engineer who oversaw original underpinning says he doesn't know why.
Moral of story is get many different opinions as I think they go for the easy option often which is to do the underpinning "just in case".

It sounds like the kind of nightmare we are afraid of getting into. Did the insurance pay for the underpinning?

Wyldwood

Yes Bob insurance did cover it. Engineer and Subsidence company did all negotiations so we didn't have that hassle at least. I agree with what someone else said, try to get a recommendation from an Architect.

bob10

John368 wrote: »

I am a chartered structural engineer, but not looking for work here I might add. I quite often look at houses to specifically advise or cracks. Often the cracks are not serious, but sometimes they are serious and remedial building works have to be carried out to make the property saleable.

A chartered engineer might be expensive but it is probably going to be worth it get some piece of mind. Most chartered structural or civil engineers do not advertise widely and get most of the work through architects so maybe that is a good place to start to look for one. Call into you local architect and ask him/her if they know a good engineer to look at the house. They will not usually mind as few architects want to get involved in structural matters like this and will be quite happy to pass the work on to an engineer.

Look for MIStructE or FIStructE after the engineer's name. (Member/fellow of the Institution of Structural Engineers). Or MIEI or FIEI (Member/fellow of the Institution of Engineers of Ireland) It is quite important that you get an engineer who has professional indemnity insurance. Few chartered engineers operate without it but there is no legal obligation for them to have it for them to hand out advice so it is up to you to check.

Sometimes the engineer cannot take on the job because he/she knows the builder or some other person involved in building and will decline the offer of taking on the job. If this happens do not get upset, he is just being professional

Thanks John, at least that is a sensible proactive way forward. Not in Waterford are you?! Hope that isnt in breach of any posting rules here. Do PM me if you have info that may be in breach maybe...?

John368

Bob

Tried to PM you but do not have enough posts yet apparently. No I am not near waterford. I would probably not take on business this way anyway. It would be regarded a bit doubtful in my profession.

Best wishes

John

bob10

Fair enough. thanks for all your help so far anyway

onq

John368 wrote: »

Bob

Tried to PM you but do not have enough posts yet apparently. No I am not near waterford. I would probably not take on business this way anyway. It would be regarded a bit doubtful in my profession.

Best wishes

John

Do you mean that you don't take on business that might be offered to you through a forum like this because of the competence of your advice, or that dealing with the problems mentioned by the poster is a type of work you don't take on?

ONQ.