A sunday morning puzzler

[Gary Prentice]

Where is the house and is the floor the original quarry tile ? If so they were bedded on nothing substantial, ours were on clinker from the local foundry which is notorious for moving on it's own. Our kitchen has a low ceiling and the floor rose so much in the middle that my head touched the light fitting, the house was built around 1860.

 

Saddleworth/Pennines. No idea what's under the lino/vinyl at present. I'm tempted to dismiss substrate change due to the localization of movement.

 

Where I used to live (Edwardian terraces c1905), one of my neighbours had a problem with a blocked downstairs loo which turned out to be caused by the roots of a Willow 4 houses away. Maybe one of the trees there is feeling adventurous but the varied ground levels make it a bit unusual.

 

Its the ground level changes, retaining walls, semi-underground garage etc. that suggest barriers that negates the possibility of roots being there. Not saying they aren't because trees will always prove you wrong. I hope that the owner will keep me informed.

 

Strucual engineer's job to work out problem then call tree man in if trees a problem. But they can get it wrong.

 

I don't see the requirement to hire an engineer to tell the owner to dig the kitchen floor up, I've already done that. The damage is localized, so if a root is the cause it's under the 'light structure damage' category of tree root problems. I may call back to suggest that the clients insurers are advised of the situation, simply to cover myself.

 

A house we looked at years ago had problems with raised floors because of subsidence. Is there any evidence of cracking round the door frames and windows ? It had sunk slightly at both ends and a supporting wall in the middle was holding the centre of the floor up so the door above it would only open half way before it grounded.

 

Sorry, I should have said in the opening post that there are no symptoms of subsidence nor history of it. Generally within the areas I work subsidence is not a consideration. The nearest shrinkable clay that I am aware of is Almondbury, Huddersfield, which is 15-20 miles away.

 

You don't say what part of the country the house is located in? If it in the northwest..ish midlands it could be red ash but unlikely if the floor was laid in the 1800's and not touched since. Red ash was used as infill for foundations and the like as it was cheap or free. The ash came from foundries and gas works, anywhere that uses large fires. Red ash is high in sulphur and when freshly laid goes off like concrete but if it starts to get wet, swells and can do what you are possibly describing. A test costs about 200 quid

 

Thanks for posting, this is new information to me. I'll contact the owner to suggest samples of the excavation are kept for examination.

 

 

 

 

Lots of good points and suggestions so far, thank you everyone who has contributed.

[Logrod]

Probably just a decomposing body

[Gary Prentice]

Probably just a decomposing body

 

That was my wife's prognosis and she doesn't even watch Brookside, Coronation Street or Eastenders:biggrin:

[daltontrees]

My randonm thoughts...

 

For the raised floor area to be caused by a tree root, the root would have to have passed under or throught the kitchen substructure/foundation and then have put on annual increments for a good number of years. That means a healthy root that is getting all it needs, particularly water. So what would it be doing there otherwise? Passing through to somewhere else? You seem to have ruled that out. If it terminates under the kitchen floor it must be getting a steady supply of water. This could be ground water or pipe leakage. If it's the latter, removal of the leakage should arrest the problem.

 

If it's not a solid floor, I can't see how a tree rot could be to blame. A twisted joist wouldn't even produce such localised swelling, you would see it over a larger area.

 

But if you don't even know if it's a solid floor, the first and only thing to do is find that out. If it is, then it's quite a small area that could be cut out after examining and recording the parttern of cracks around the bump. A heavy solid floor slab won't lift locally, nor will a thin reinfoirced one. So the offending area might be a thin unreinforced slab that could be opened up with a bolster an hammer. Whatever's there will reveal itself. A tree root would probably need to be in almost direct contact with the underside of the slab. If I found a root I'd take a sample but I'd be tempted to inject some amount of systemic poison and if this is done at cambial level rather than right into the wood it should kill the root without carrying too much into the above-ground parts of the tree.

 

If it's a leak, that will need to be addressed or the problem could recur and may be doiing other unseen damage.

 

Another thought - protimeters are pretty good at checking moisture levels in concrete. Under vinyl will be a very distorted reading, so the whole floor would need to be stripped and left to air-dry well ventilated for a summer week before any meaningful readings could be taken. A protimeter will only give relative readings unlike the fairly absolute readings they give in wood.

[Gary Prentice]

 

If I found a root I'd take a sample but I'd be tempted to inject some amount of systemic poison and if this is done at cambial level rather than right into the wood it should kill the root without carrying too much into the above-ground parts of the tree.

 

 

I'd dismissed this idea, even if indeed a root is the cause, because of ill affect to the whole tree. I can't say that I have any knowledge on localized root poisoning to be honest though. Opens another door to research.

 

I hate all the unknowns at the moment. I don't even know if the tree enjoys any statutory protection, because the call came after five on friday and there's no online search facility available. I also suspect that I'm not going to be privy to the results or indeed the conclusions of this situation.

 

A further issue that may factor into the equation is that the neighbours house has been bequeathed to a daughter in Scotland. The client is unaware whether it will be offered onto the open market or let. If it is sold, a new owner may be less willing to remove the tree, so pre-emptive felling may occur (in the absence of solid evidence) due to the existing goodwill/relationship with the deceased's daughter.

[woody paul]

I don't see the requirement to hire an engineer to tell the owner to dig the kitchen floor up, I've already done that. The damage is localized, so if a root is the cause it's under the 'light structure damage' category of tree root problems. I may call back to suggest that the clients insurers are advised of the situation, simply to cover myself.

 

 

Lots of good points and suggestions so far, thank you everyone who has contributed.

 

What it boils down is, what qualification have you got to advice, and any strucual damage needs looking at properly and insurance companys will cop out if not told of any problem they need to now about so telling them is best.

[Gary Prentice]

A did say in my reply, to you, of my intention to contact the client and propose contacting their insurers.

 

This isn't my first rodeo, so to speak, but thank you for posting.

[fagus]

Apologies if I have misread your description.My stock answer in root situations is `Neither me or you have X-ray eyes so we need evidence that roots are present and we have shrinkable clay on site. this requires somehow exposing a trench to intercept any roots. It is all conjecture without facts on roots, soil types, and construction

We can only advise on what we are qualified in; which is often only trees; soil and engineering best left to experts in those fields. Advising outside your competence can be costly to you.

[kevinjohnsonmbe]

You say "a curious phone call" Gary, and it does seem curious from what's been described so far. If I put myself in the householders' position, I would probably have called a builder / civil engineer given the circumstances you describe. Did they say what caused them to call a tree guy? Do they maybe know more than they are letting on or have they preformed a conclusion that it's a root problem? It does seem curious.

[Gary Prentice]

Apologies if I have misread your description.My stock answer in root situations is `Neither me or you have X-ray eyes so we need evidence that roots are present and we have shrinkable clay on site. this requires somehow exposing a trench to intercept any roots. It is all conjecture without facts on roots, soil types, and construction

We can only advise on what we are qualified in; which is often only trees; soil and engineering best left to experts in those fields. Advising outside your competence can be costly to you.

 

No shrinkable clay that I'm aware/ evidence of subsidence and if it's heave it's the most localized heave I've ever heard of:biggrin:

 

I advised lifting the flooring to find out what lay beneath.