Subsidence

[Chris at eden]

Building regs do not apply to all structures particularly conservatorys

 

 

Yes and I actually said that in the second paragraph of the post.

[Chris at eden]

1) Yes on an annual basis but this assumes a number of things: independence of data (not true) trees, old buildings and clay soil lead to claims being focused on particularly areas; if you are on non clay soils the chances of tree related subs is close to zero.

 

2) A claim is likely to go on for several years so perhaps 1% of buildings may be experiencing a subsidence claim at any one time.

 

3) Once your house has had subsidence, even though fixed, the owner has to declare this to the insurer and the insurer may alter their premium......so possibly 1 million houses out of the 4.7 million on clay should be ticking that box. There are a variety of insurance implications from this some of which leads to tree surveys, tree pruning and the like.

 

Depending on what you are trying to do subsidence is an issue that possibly blights far more properties than the 0.23% per year figure implies.

 

 

I never said that subsidence blights only 0.23% of properties, I said that was the annual risk. That is how the HSE calculates risk at the end of the day. If you apply risk to include anything that has happened in recorded history then NTSG would make much grimmer reading. My figures are based on your stats.

 

I think your third point is a good one though and for this reason I wouldn't consider buying a house which had suffered subsidence unless I had a considerable price reduction.

[DanBB]

Thank for your advice. It is very helpful to hear from people who had experience with these kind of issues. We are looking at the remedial work to be done now ( just finalizing the purchase ) any idea how much these kind of repairs cost. ie: crack to be repaired with helifix bars *3, the garage need to be tied in to the main structure, the boundary wall taken down and rebuilt, and the trees cut down. I asked for some quotes from builders but they are taking their time. Plus another question, we were told that further monitoring will be needed, is there any special guarantees I should ask from the builders, how does this work. The structural engineer thinks that once the trees are cut down most problems would solve itself, however would you start fixing cracks/walls etc straight after cutting the trees down or would you wait for the ground to settle.

 

Just wanted to say a massive thank you for all your responses, as they helped us a lot.

[Gary Prentice]

As just a quick reply, the soil needs to rewet below the garage before any remedial works. The soil is probably in a state of dessication (due to the trees) and muchreduced in volume. As the soil returns to somewhere near normal moisture levels it will expand and cracks will close.

 

This is why cracks open and close during different seasons with tree related subsideence problems.

[bankhouse builder]

Hi

I am glad you have taken this one on I think this will prove to be a worthwhile exercise especially if you have obtained a good reduction on the asking price.

My advice now is that I would carry the works out in the following order this how I carried out the subsidence job I did a few years back and it was successful. This will not be a quick process but it takes time to do the job right so you don't have problems later down the line

 

1 remove the trees immediately as you get possession .

2 Employ your engineer to fix tell tales over the cracks and take readings we took them once in spring and once around second week in September your cracks should start and close up immediately only by a small amount but they will close up gradually.

3 You could help matters along in the first year by diverting fallpipes so that the water soaks the affected ground and allows the soil regain its structure.

4Once your engineer has said the ground has stabilised (the soil will still move seasonally but you have removed the factor affecting it abnormally the trees) and the cracks closed you can then and only then do the structural repairs and any cosmetic repairs

Good luck