Extension - how much? (Before house purchase)

[pidsy]

Looking at a potential house purchase but it would have to have an extension for it to work.

Planning was granted in 2020 but it was never built.
The agents aren’t being very knowledgeable/helpful - so would the consent still be valid?

I would need to do the build immediately- losing the kitchen, bathroom and boiler makes it uninhabitable for the duration of the work.

The river means it needs to be piled - 300mm piles at a depth of 5000mm. Getting a mini piled in is possible but not straight forward.

A friend of mine is a QS but away on holiday so I thought I’d throw it open to you lot to interpret…



Existing floor plan.


Proposed floor plan (ground floor)


Proposed floor plan (first floor)


Garden elevation


Pile cross section



How it looks currently- with indication of extension size and change in roof pitch.

I have a figure in mind - I have access to v-good trades but it’s been a while since I’ve overseen a project like this.

Appreciate any and all thoughts.

[Cow Corner 2.0]

The planning is unlikely to still be valid (it’s normally valid for three years, unless a demonstrable and recorded start has been made).

I’ll leave it to others to comment on costs, but be wary of the usual ‘I did similar in 2020 for 50p’ comments… costs have gone up significantly in recent years, so much better to get your QS or a good contractor to give you a budget cost before you purchase - having the drawings and knowing piling will be required should help significantly.

[eliot]

i would be asking the current owners why they didn't go ahead - expect something along the lines of much sucking of teeth around the foundations.

[pidsy]

Thanks for the comments so far - I’m very aware of the increase in costs since covid - I usually deal commercial projects and our uplift in costs have been crazy.

Thanks for the mention of 3 year life of the PP. I will mention to the agents.

[scenario8]

Fwiw most local authorities (in England - no idea in the rest of the UK) have searchable planning portals. You may well find the planning documents there. If not, in my experience, a phone call usually clears things up in simple matters like this.

[pidsy]

scenario8 said:

Fwiw most local authorities (in England - no idea in the rest of the UK) have searchable planning portals. You may well find the planning documents there. If not, in my experience, a phone call usually clears things up in simple matters like this.

That’s where I got the above drawings from.
The planning approval didn’t have an expiry date. I would imagine it would need to be reviewed by the authority anyway.

[Prisoner 24601]

A QS isn't going to be much help here. Say they spend several hours on it and work out a pretty decent estimate at £137,500. You go for quotes from a builder and they say £195,000. You counter with your QS quote, they won't entertain it - "yeah thanks for that, as i said, i can do it for £195,000".

Go straight for 3 Builders quotes/estimates.

[scenario8]

pidsy said:

scenario8 said:

Fwiw most local authorities (in England - no idea in the rest of the UK) have searchable planning portals. You may well find the planning documents there. If not, in my experience, a phone call usually clears things up in simple matters like this.

That s where I got the above drawings from.
The planning approval didn t have an expiry date. I would imagine it would need to be reviewed by the authority anyway.

Was it not mentioned as @ condition on the Decision (Granted) letter? Or was the letter not available?

Besides, it’s usually three years and you might not want the same thing as the original applicant anyway.

Best of luck either way whatever happens. The plot looks pretty.

[Sheepshanks]

Is the cost to include new kitchen and bathroom? Will the trades you know do work at mates rates?

If paying in the normal way, don’t forget about VAT.

I have no idea how much piling costs but as a householder who paid for a chunky extension a few years ago I’d be thinking in terms of £250K inc VAT for the whole job.

[Hustle_]

Next door's already been done? Piling there?

Edited by Hustle_ on Monday 26th October 10:38

[Cow Corner 2.0]

Prisoner 24601 said:

A QS isn't going to be much help here. Say they spend several hours on it and work out a pretty decent estimate at £137,500. You go for quotes from a builder and they say £195,000. You counter with your QS quote, they won't entertain it - "yeah thanks for that, as i said, i can do it for £195,000".

Go straight for 3 Builders quotes/estimates.

This is a good point, but getting three contractors to spend the time to do a detailed quote on a property the OP hasn’t even bought yet might not be that easy, unless they have good contacts.

[dmsims]

Don't forget about party wall costs and associated possible neighbour friction

[Sheepshanks]

Cow Corner 2.0 said:

Prisoner 24601 said:

A QS isn't going to be much help here. Say they spend several hours on it and work out a pretty decent estimate at £137,500. You go for quotes from a builder and they say £195,000. You counter with your QS quote, they won't entertain it - "yeah thanks for that, as i said, i can do it for £195,000".

Go straight for 3 Builders quotes/estimates.

This is a good point, but getting three contractors to spend the time to do a detailed quote on a property the OP hasn t even bought yet might not be that easy, unless they have good contacts.

If the OP is intending to project manage it himself then he should, especially if he knows people, be able to bring it in for what the QS says.

[The Three D Mucketeer]

Pretty, but after last summer , I'd be more concerned about the fire risk of the surrounding trees.

[gangzoom]

pidsy said:

Thanks for the comments so far - I m very aware of the increase in costs since covid - I usually deal commercial projects and our uplift in costs have been crazy.

Thanks for the mention of 3 year life of the PP. I will mention to the agents.

If you look on the local planning portal it'll tell you if additional documents have being submitted. But its 3 years than it expires unless foundations etc has being started which by the looks of the picture hasn't. So you will have to reapply.

For cost it use to be £2000/sq meter as a good rough estimate, I think that figure is now close to £3000/sq mete, our renovation came out at £2560/sq meter a few years.

If you do all the work yourself than you can probably do it for £100 .

Edited by gangzoom on Monday 26th October 11:10

[alscar]

PP is valid for normally 3 years unless the permission letter gives a longer date or the foundations have been started ( even if legally only on a very basic basis ) in which case the permission last virtually indefinitely.
If no work at all has been started then the pp has probably lapsed and you would need to start again from the beginning.

[v8notbrave]

You're going to need to work with broad numbers

Built something similar size in Scotland last yr but I knew and employed each contractor directly at 2k per sq/m ish. Me decorating and doing tiny bits, this was cheaper than a conservatory. This was just a room no plumbing or anything

If you go for a fancy builder who has nice vans and the ubiquitous LR defender etc then you're nearer to 3k, plus your piling, kitchen, plumbings etc

Looks like 21sq/m ish so will be a nice size

Planning will have lapsed unless in Scotland

[pidsy]

More responses than I’d hoped for. Appreciated!

Have gone back to the agent to say that it’s a no go without confirming the PP being current. If they need to do it all again, that’s on them. I don’t need to move and would stay where I am till works are complete.

As mentioned above, it’s not mine so can’t really go too deep in terms of getting people in etc, and don’t want to spend money on potentials - I have friendly trades and a couple of builders who are looking at the plans currently to give me a ball park figure.

Have also found a local piling company who are looking at the full piling recommendations- and should come back to me in the next few days.

Even at 2-3k psqm- it’s not as bad as I thought. I’d do the majority of the second fix myself.

PH at its best - all opinions and thoughts are welcome.

[alscar]

pidsy said:

More responses than I d hoped for. Appreciated!

Have gone back to the agent to say that it s a no go without confirming the PP being current. If they need to do it all again, that s on them. I don t need to move and would stay where I am till works are complete.

As mentioned above, it s not mine so can t really go too deep in terms of getting people in etc, and don t want to spend money on potentials - I have friendly trades and a couple of builders who are looking at the plans currently to give me a ball park figure.

Have also found a local piling company who are looking at the full piling recommendations- and should come back to me in the next few days.

Even at 2-3k psqm- it s not as bad as I thought. I d do the majority of the second fix myself.

PH at its best - all opinions and thoughts are welcome.

If the current owners needs to apply for pp then it will be treated as a fresh application and the planners will also review it against any local planning rules which may of course have changed since the one in 2020.
In other words it won't be a quick process !

[andya7]

(not overly difficult to find/locate the property) The Decision Notice states that permission was granted on 14 September 2020 and states;

...in pursuance of powers under the above mentioned act, hereby GRANT, subject to the development beginning not later than 3 years from the date hereof...

So, if there has been no material commencement (as others have said) then the permission has lapsed. I see no obvious reason why it would be refused if resubmitted however there are cost and time implications (which you have mentioned).

As for build costs, I could contact a client that has just had a piled foundation extension but I think you might just forget the property now you know that there is no planning permission :-)

If you approach a builder and mention that you don't own it yet, then they will only give you a 'rough figure' based on a £/m2 that they know they can do it for... then they will add on a suitable cover for the unexpected i.e. piling, access (there isn't any...), storage (there isn't any...) which is all going to make it more expensive and potentially they don't want the hassle of the location/access/storage...