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By Hudson1984
#1198691
anyone here a builder?

one of the many projects we're considering at the new house...

at the moment there's a daft sun room on the side of the house, connects to what we're using as a gym. I'd like to extend and knock out the party wall (so there would need to be a big steel bar holding the roof up - that portion of the house is a flat roof though with no upstairs)

dimensions would be:

3.36m x 4.78m

but only two walls would need making as two would be the exisiting house.

Then cover it with flat roofing.

Be interested to know what the cost would be roughly
By Geoff_S
#1198734
There are a few websites around that will provide a ballpark estimate. They seem to suggest anything from £1500-£4000 per square metre, dependant
on location, type of build and quality of materials.

But so many things can affect the price. When we had a small extension, very similar to yours by the sound of it, we had to have 1.6m of
concrete foundation because of tree location, which made a big difference.

What was eye watering were the ongoing costs. For example, the building estimate we received assumed 2 sockets and 1 light fitting. It was
all above board, but of course we wanted more than that, so that was extra.

Does the estimate include decorating? Does it include plumbing? What type of flat roof, felt, rubber, fibreglass? etc etc.

Your questions is quite difficult to answer. I think the only way is to spend time preparing a detail plan of your requirements and get some
builders estimates. And try to include everything that you can think of. It's sometimes easier to cut back than it is to find the extra.

I apologise if I am telling how to suck eggs.

By the way, I am not a builder, but have been a customer too many times, good and very, very bad, and hopefully the last just recently with our extension.
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By NickN
#1198745
Hudson1984 wrote:at the moment there's a daft sun room on the side of the house, connects to what we're using as a gym. I'd like to extend and knock out the party wall


:shock: I assume (and hope) you mean partition wall (exterior wall of house plus wall of gym)? Knocking down party walls could get you in trouble with the neighbours... :mrgreen:


Hudson1984 wrote:but only two walls would need making as two would be the exisiting house.
Then cover it with flat roofing.


Sounds as if the sun room is just a wooden or plastic structure, so no proper walls, even dwarf ones? Which could well mean digging and placing suitable foundations for any new block/brick walls, plus both walls would need to be tied in with the current structures each side, ultimately you may find not much difference in cost between that and a simple four wall new structure. Whether you use block + render or brick makes a difference to price, and being between two structures means having a think about roof slope direction, and the feasibility of lead flashing on the two existing walls, or making the new roof higher to drain onto one side or the other.
These days EPDM rubber roofing is widely recommended (and having used several times myself, it is the way to go, stands up to a lot more abuse than felt).

Very difficult to estimate any prices though, as Geoff says, without knowing a fair bit more detail about various aspects of it. But extremely roughly, just for construction assuming double skin and foundations needed I'd say you should budget a minimum of 10k, with electrics, decorating, plastering, flooring etc. on top. I'm no professional builder either but have had plenty of work done over the years and done a lot of work myself too.
By novocaine
#1198752
it's outside permitted development so you'll need plans and as it involves removal of external walls you'll need structural calcs done too.

1300 quid ish for that excluding changes and amendments post approval by planning office.
1500-3000 per square metre as said above is about the going rate round here depending on what you want and what you consider to be final fit and finish (for me it's up to plastered walls. Others want tiles, paint, doors the whole caboodle), also depends on who manages it.

guess it's a "how long is a piece of string" question. ask around for a trusted local builder and get him out for a quote and to talk about what you can and can't do, they normally know, ask him about an architect or drafter for the plans, he'll know someone.
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By Lons
#1198762
I'm a retired builder but there's no way I would ever have given a ballpark estimate or any indications without a site visit and full details of a customers requirements and expectations.

There is little detail in your initial post so it's difficult to envisage what you're describing. You need to get out your tape measure and a pencil and paper and draw it out, doesn't need to be architect standard for estmate purpose, just accurate as far as measurements, existing construction, and what you want included by way of electrics, decor etc. Nothing to stop you posting drawings and a few photos on the forum and you might get some opinions on cost from a few members.

If you're knocking through an outside wall it is most likely cavity, builder will need to know if the cavity is insulated, whether and obstructions, tree roots, drainage close to the new foundation areas and a lot more besides.
Note that it sounds as if you intend to convert the existing sunroom into a habitable room and there are regulations regarding construction and insulation as well as probable electric work and heating so you will need building regulation approval.
That area of flat roof won't be cheap and it's likely you'll have to alter it substantially to accommodate insulation so one suggestion is to get estimates for a pitched tiled roof as an alternative and compare the difference. Apart from being a better solution it usually adds value and makes a property more saleable than a flat roof. You may need planning approval but in many cases not so would need to check that.

Get at least 3 estimates based on your drawings and make notes as the builders will offer suggestions and alternatives, I would ask more than 3 builders as some might not turn up, get recommendations from friends and family and if you do decide to go ahead do some careful research into the ones you choose.
If any are significantly cheaper than expected there's a reason and you'll get what you pay for, any significantly more expensive may be overpricing as they don't need or want the job. Make sure there is a written detailed contract outlining exactly what they will do and query anything not listed before work starts. It's not unreasonable to be asked for a deposit but don't pay for the job upfront to protect yourself, a reputable company will accept that but expect to be paid promptly on completion.

Cheers
Bob
By MikeG.
#1198771
"How much is it going to cost, Mr Architect?"

"I don't know until we've got a design."

"I don't want to get a design done unless I know I can afford the building work."
By treeturner123
#1198844
In my experience, the hardest thing at the moment is GETTING a quote from a builder

(Said with feeling after chasing up 2 builders who have the plans, seen the site and still don't seem inclined to comeback with any price).

Phil
By Keith 66
#1198890
We built a big extension 15 years ago, the lower figure of £1500 per sq m was surprisingly accurate. I ran the job & got a friend who is a builder to do foundations walls & basic structure. Other trades such as sparks, plasterer, roofer were engaged as required through recomendation. I worked alongside & troubleshot as required (quite a bit) much cash was dispensed & this bought the price down. A surprisingly big cost was muckaway, a little trench or oversite clearance turns into an almighty pile of dirt. Our builder had budgeted for 8 grab lorry loads. In the end it took 18 loads at £150 a time. But we saved on other bits so it equaled out in the end. If we had had a builder to run the whole job it would have cost over twice as much. And we are still friends with our builder, Bonus!
By Hudson1984
#1198977
cheers all that's really useful. I'll "budget" toward the £1500 per m2.

Think what i'll do is live here a little longer lol, see what we really definitely need and do a few sketchup plans and then get them drawn up properly. Least I'll have something to show a builder then.

but could all be a flop if we didn't get planning permission - so have to look at the paper side of stuff first :)
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By Lons
#1198992
treeturner123 wrote:In my experience, the hardest thing at the moment is GETTING a quote from a builder

(Said with feeling after chasing up 2 builders who have the plans, seen the site and still don't seem inclined to comeback with any price).

Phil

I'll never really understand that either Phil but it's very common. As I said though depending on your project it isn't just a few minutes to work out and if sole traders these guys are probably out on site 6 days a week.

My reputation meant everything and I never took a job for anyone I didn't know or where I hadn't been recommended, any calls I got from people ringing around were politely refused although I did visit one or two I felt sorry for on the clear understanding it was to offer advice only. It did help however that I was never short of work.

I would always visit a site if I had agreed to and if I didn't fancy the job would say so there and then giving my reasons, if a was going to quote then I would say how long that would take. The practice of overpricing a job because you don't really want it is imo sharp practice. Builders who keep people hanging on are harming their reputation although the reasons are understandable as for a small business like mine it's pretty daunting after a long hard day to come home to paperwork and return phone calls and then needing to spend time producing proper estimates which as I said are time consuming unless you take the risk of applying standard square metre figures. I worked mine out properly so that first I was sure I would make adequate profit and second the price I estimated was as accurate as possible for my customer.
I built up a good reputation and several long term customers never wanted a price as they knew I wouldn't rip them off.

cheers
Bob
By MikeG.
#1200223
Hudson1984 wrote:cheers all that's really useful. I'll "budget" toward the £1500 per m2.

Think what i'll do is live here a little longer lol, see what we really definitely need and do a few sketchup plans and then get them drawn up properly. Least I'll have something to show a builder then.

but could all be a flop if we didn't get planning permission - so have to look at the paper side of stuff first :)


Blimey. That really is optimistic. As a broad-brush budget figure just to set the parameters for the design you should allow at least £2000 p/sq/m + VAT.
By MikeG.
#1200226
Lons wrote:
treeturner123 wrote:In my experience, the hardest thing at the moment is GETTING a quote from a builder

(Said with feeling after chasing up 2 builders who have the plans, seen the site and still don't seem inclined to comeback with any price).

Phil

I'll never really understand that either Phil but it's very common. As I said though depending on your project it isn't just a few minutes to work out and if sole traders these guys are probably out on site 6 days a week.

My reputation meant everything and I never took a job for anyone I didn't know or where I hadn't been recommended, any calls I got from people ringing around were politely refused although I did visit one or two I felt sorry for on the clear understanding it was to offer advice only. It did help however that I was never short of work.

I would always visit a site if I had agreed to and if I didn't fancy the job would say so there and then giving my reasons, if a was going to quote then I would say how long that would take. The practice of overpricing a job because you don't really want it is imo sharp practice. Builders who keep people hanging on are harming their reputation although the reasons are understandable as for a small business like mine it's pretty daunting after a long hard day to come home to paperwork and return phone calls and then needing to spend time producing proper estimates which as I said are time consuming unless you take the risk of applying standard square metre figures. I worked mine out properly so that first I was sure I would make adequate profit and second the price I estimated was as accurate as possible for my customer.
I built up a good reputation and several long term customers never wanted a price as they knew I wouldn't rip them off.

cheers
Bob


Most builders I get involved with use a QS to do their pricing for them. This costs them about £600 for a typical domestic extension & alteration, and much more for bigger jobs. This is one reason why I seek interest first from builders before going out to tender, and why I never ask more than 3 builders to quote for a job. In comparison with a builder's estimate, a QS price is fantastic, with itemised and individually costed elements making things clear both for the customer, and helping in the contract valuations every month.

-

One of my favourite local builders is booked up until late 2019. Most others are almost as busy. Now is not an easy time to get builders to quote, and this will be reflected in the prices that people can expect to pay.
By HOJ
#1200239
I would initially find a builder, preferably one who comes with recommendations, and someone you can work with, they will be able to give you guidance as to what can be done and will probably know the local area, with regards any known issues with soil types which will dictate the type of foundations required, too many times I have seen assumptions made, only to find the site is on impermeable clay with a high water table and trees, inuring considerable costs, for instance.

They may also be able to give guidance on the suitability of the existing building/footings for any additional structural loads that you will add.

Whilst this is only a relatively small project you need to establish an affordable budget, again I have been to many potential projects where the budget just wasn't realistic enough, speculative meter rates are fine but it is all too easy to spend money on designers, planning applications, Structural Engineer's and building regulations only to find the cost to build is prohibitive.
By MikeG.
#1200241
HOJ wrote:I would initially find a builder.........


And the first thing he'll say is "have you got any drawings?". Start with an architect, not a builder.