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Buying a house that has been extended by current owners

Jet
Posts: 1,642 Forumite



My son and his GF are thinking about putting an offer in on a house.
It's been extended by the current owners and the work has been done by the current owner - a builder by trade.
What paperwork should they be asking for to check it has all been approved and signed off?
Also, what happens with regards to the council tax being re-assessed? It currently is in a band for the original size but I suspect it will change at some point?
It's been extended by the current owners and the work has been done by the current owner - a builder by trade.
What paperwork should they be asking for to check it has all been approved and signed off?
Also, what happens with regards to the council tax being re-assessed? It currently is in a band for the original size but I suspect it will change at some point?
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Comments
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I'd be getting the conveyancer to check that it's been correctly approved etc.
When you buy a house it is very possible that it will be re-assesed, it happened to a work colleague and also on this thread.
Council tax banding change notification after buying house — MoneySavingExpert Forum
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Peter999_2 said:I'd be getting the conveyancer to check that it's been correctly approved etc.
When you buy a house it is very possible that it will be re-assesed, it happened to a work colleague and also on this thread.
Council tax banding change notification after buying house — MoneySavingExpert Forum
The house I live in is band B for council tax, but according to calculators, should be band C. So far the council hasn't said anything and I'm keeping quiet, but I've heard from neighbours that getting an extension may trigger the increase. I'm guessing I've been here long enough that if the sale was going to trigger the banding change - it probably would have by now.0 -
Start by looking the house up at
https://www.tax.service.gov.uk/check-council-tax-band/search
And see if, after telling you what your and neighbours’ banding is, the line described as “Improvement Indicator” says “yes” or “no”. We converted our home’s garage into an en-suite room, and cos we correctly notified the Council Building Control inspector and got a certificate, they obviously told the CT people, so ours shows as “yes” with the implication that when we next sell, it might be re-evaluated.
And I’ve not only got the Building Control certificate but other stuff like Electrical certs; so, while none of this can be trusted til your conveyancing solicitor gets it in writing, you could just ask if there are any certs.And in the unlikely event that it was such a big extension that it exceeded “permitted development” , you could ask whether planning permission was sought or granted (although you could look that up yourself, by property address on the Council website)1 -
Have you looked at the council website? There is usually a section where you can look at building plans / regulations that have been submitted to be approved0
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I think the council tax band gets updated when a house is sold. So he might sell you his band B house, which will become a band C house (due to the extension) when your purchase completes.Before crowbars were invented, crows just drank at home.1
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RHemmings said:Peter999_2 said:I'd be getting the conveyancer to check that it's been correctly approved etc.
When you buy a house it is very possible that it will be re-assesed, it happened to a work colleague and also on this thread.
Council tax banding change notification after buying house — MoneySavingExpert Forum
The house I live in is band B for council tax, but according to calculators, should be band C. So far the council hasn't said anything and I'm keeping quiet, but I've heard from neighbours that getting an extension may trigger the increase. I'm guessing I've been here long enough that if the sale was going to trigger the banding change - it probably would have by now.If you are querying your Council Tax band would you please state whether you are in England, Scotland or Wales0 -
IIRC you can check the banding for council tax and if it will increase when the property changes hands, there will be an "improvement marker" against it. IN fact, I've just checked it - use the checker on gov.uk, put the details in, then click through to the property itself - check the line that says "Improvement indicator". We bought a house last year which had been extended and checked it that way - all good for us, and in fact even next door's HUUUUUGE extension hasn't triggered anything, it appears!🎉 MORTGAGE FREE (First time!) 30/09/2016 🎉 And now we go again…New mortgage taken 01/09/23 🏡
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Balance as at 31/08/24 = £105,400.00 Balance as at 31/12/24 = £102,500.00
£100k barrier broken 1/4/25SOA CALCULATOR (for DFW newbies): SOA Calculatorshe/her0 -
lincroft1710 said:RHemmings said:Peter999_2 said:I'd be getting the conveyancer to check that it's been correctly approved etc.
When you buy a house it is very possible that it will be re-assesed, it happened to a work colleague and also on this thread.
Council tax banding change notification after buying house — MoneySavingExpert Forum
The house I live in is band B for council tax, but according to calculators, should be band C. So far the council hasn't said anything and I'm keeping quiet, but I've heard from neighbours that getting an extension may trigger the increase. I'm guessing I've been here long enough that if the sale was going to trigger the banding change - it probably would have by now.
However, when I used the link in this thread further up, I found that all of the similarish houses in my part of the road (mine is probably the cheapest due to no extension at all and old roof) were already band C, except for two. One being mine.
As you infer (to my reading), the band change is coming...0 -
RHemmings said:
The house I live in is band B for council tax, but according to calculators, should be band C. So far the council hasn't said anything and I'm keeping quiet, but I've heard from neighbours that getting an extension may trigger the increase. I'm guessing I've been here long enough that if the sale was going to trigger the banding change - it probably would have by now.Are you saying that your property was extended by your vendors prior to you buying it? If it hasn't, then it won't be rebanded. Under current rules, if you extend the property it will remain in the existing band until such time as you sell. The house sale will only trigger a potential reband if it has an improvement indicator lodged with the council.Incidentally we extended our previous house which should have triggered a rebanding when we sold it, but for some reason the improvement indicator was missed even though our extension was all done with planning permission and building control signoff. It's been 5 years since we moved out and the house is still band E. Others that have been extended in a similar way have been rebanded to F when the property has changed hands. It's a mistake somewhere at the council.Make £2025 in 2025
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Total £915.94/£2025 45.2%
Make £2024 in 2024
Prolific £907.37, Chase Intt £59.97, Chase roundup int £3.55, Chase CB £122.88, Roadkill £1.30, Octopus referral reward £50, Octopoints £70.46, Topcashback £112.03, Shopmium referral £3, Iceland bonus £4, Ipsos survey £20, Misc Sales £55.44Total £1410/£2024 70%Make £2023 in 2023 Total: £2606.33/£2023 128.8%0 -
OP, if it was permitted development, you'd be looking for building control sign off, gas and electric certificates. If it required planning permission, then you'd need the approval docs for that as well as the others - as a minimum.
I wouldn't worry about council tax re- banding myself - we're moving from a B to a C soon and it's about an extra £19 a month, so hardly worth sweating over given we're getting one and a half extra bedrooms and a much bigger garden.0
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