Possible subsidence in living room by bay window

Hi All,

I’m in the process of selling my property and the chap buying the property had a survey, which it was noted that there is possible subsidence in the front living room - approx 2/3 from inside the bay window.

A Timber/Damp report was then requested, which has highlighted that:

1) the flooring is lowering 2.5m in total from front bay window
2) Three areas of damp detected - rear of living room, hallway to kitchen and downstairs wall between kitchen/bathroom

the chap carrying out the report said typically a damp proof course for these areas would cost between 2000-2500

However my main concern is the 2.5m of subsidence. The chap said the laminated flooring will need to be removed in this area then the floorboards. Once they have been removed the floorboard joists will need to be replaced

Typically what is the cost of replacing the floorboard joists, approx 4m by 4m, then replacing the floorboards then relaying the laminated flooring?

I am prepared to take the hit and deduct this amount from the price that we agreed to sell the house at.

If anyone could kindly estimate the cost of replacing floorboard joists and a damp proof course that would be fabulous

Many thanks
Charlie:-)
 
you need to look at stuff a bit more carefully. 2.5 metres? - - 9 feet?
Are we looking at 25 mm , or 250 mm or 2.5mm?
If it's subsided 9 foot in depth since you lived there, my advice would be to order a taxi and don't allow anyone that you like near the property for the foreseeable future.

things like 4m and such likes are a waste of time until we know your measuring abilities, which appear poor, very poor up to now, at least I hope so
 
Call different builders .not necessarily in your area
Get lots of quotes . There are some serious issues by the sound of it with your property. Ask if builder has a profile of work recently done. dont pay upfront. payment in stages . As builders do sub contract if busy.



I recently had a new garage extension I saved 2k by dismantling the garage. And digging out my old footing with a friend. Won't go into figures .one builder wanted 6k more than the others. A good builder will always be busy. It may take months to get your desired builder. Good luck.
 
Cheers guys

Let me get the calculations correct - sorry it was late last night when I sent this message

The area in question of subsidence is 4 metre squared. The depth is of subsidence so far is 5-8mm. But it’s noticeable as laminated flooring is laid down.

It’s been brought to my attention by the buyer and the Timber/Damp proof specialist so will also write it in his report :-(

So l need to get it sorted or best to get a few quotes then knock it off the house price
 
I see, so I've no idea where you got the 2.5m from, but nevermind.
The depth of the subsidence isn't really a problem, half an inch or two inches makes no odds, but it's not 'subsidence' as in the house has sunk, it simply means the joist ends have rotted where they sit on the outside walls, this usually happens when underfloor vents have been blocked, often when people lay drives / patios etc they raise the level and pave over the vents.
Without ventilation, the joist ends rot and the floor becomes springy.
The lack of ventilation won't be doing the damp problems any favours neither.
It's difficult to price up because no one knows what they will find when they take up the floorboards.
If the laminate has been down a long time, the chances are it won't be able to be re-used as there will be some breakages, and replacement boards won't be available, so you can save yourself some money here by taking up the laminate yourself and chucking it out - new laminate is cheap as chips when the time comes to replace it.
Floorboards will need to be lifted along the outside wall and in the bay as this is where the joist end rot will be.
The old joists will be cut out a foot or two back from the rot and new ones fixed in, and stitched into the old joists, and propped up with bricks/blocks underneath for added stability. There may be 2 or 3 joist ends or there could be five or six, there's a video here if you want to do it yourself:
 
Brilliant

I’m glad it’s not subsidence as just rotten joists

It makes sense to get a few quotes as well

I was worried as both survey reports have come back with it stating subsidence but the house it’s falling so makes sense it’s caused by rotten joists

Thanks for the video too

Makes complete sense now :-)
 
what did the surveyor's report say about subsidence? - just the floor or the actual house?
are there any cracks in the brickwork outside? - usually above doors and above and below windows.
If it's just the floor, it's 99% certain to be joist-end rot due to poor ventilation
 
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Cool.
the joist end replacement isn't a big job and can be DIY by anyone with rudimentary joinery skills.
I'd expect a builder to do this easily in two days and materials to be less than £200 so A charge of £600 or thereabouts is my estimation, a bit extra if you want a few exterior vents installing (recomended)
The damp course is the biggest job as there's plastering and new skirting boards to factor in.
If you get the same builder to do both jobs, you're looking around 3-4 days and maybe 2.5k all in
 
It’s absolutely ridiculous quote from the Buyers chap that did the survey for Timber and Damp

For
2 walls that need damp proof course
Lifting laminating floor, removing old joists and replacing them, then replacing the floorboards too

£7300 lol

I’ve got two local independent companies to quote for me the work - one said it’s between 1200-1800 all in...

That’s a staggering quote - no wonder he lives in a 750k house
 
If your competent.
( NOT MEANING YOUR NOT)
But googling terms and an understanding of what a builder is whittering on about is quite daunting

You have done really well £7500
To under 2k.all in.
Pays to shop around as I found out.
Builder comes in to my home gives a price.. As if I would take 1st quote.

Next day cppl skips arrived. and went into my garage with a big hammer drill.. And bolster hammer, and chisel.. hard work but saved Myself 2k.. minus £150; for skips.

Are you down sizing ?
 
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Are the bay windows original to the house or put in later? If later, check that the put a proper lintel in to compensate as some cowboys don't bother.
 
Thanks for the reply :-)

Getting a bigger place and closer to schools - future proofing for when the kids arrive - well that’s the next stage

It’s all original windows - so it will come down to rotten joists and that’s what’s in the report too

I bet the buyer will have paid £500 for that report
 
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It’s absolutely ridiculous quote from the Buyers chap that did the survey for Timber and Damp

For
2 walls that need damp proof course
Lifting laminating floor, removing old joists and replacing them, then replacing the floorboards too

£7300 lol

I’ve got two local independent companies to quote for me the work - one said it’s between 1200-1800 all in...

That’s a staggering quote - no wonder he lives in a 750k house


He quoted 7.3k because that's what he's trying to get reduced off the price of the house.
Just make sure you get photos of the work as it's being done and maybe a DP cert to show the surveyor afterwards
 
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