How much does a building extension cost ?

[hopkins]

I know this is a very general question but looking to get an extension/conservatory build about 4 Foot X 7 Foot. It would lead out from living room (in to the back garden) which i think we would seperate from it by a door.

Ive been told to expect £1000 per Square meter.

Also, any reputable building firms out there ? Our neighbours got ripped of recently and had to get a second set of builders in to finish the job.

Thanks.

 

[cliveh27]

I'm looking to build a 4m x 3m conservatory. I've had one quote so far of around £12,000, which matches your £1000 per m2. My advice would be to get 2 or 3 quotes, including at least one from a local building firm as well as a specialist conservatory/window company. I'm in Wiltshire, so can't recommend a local Brighton firm for you. Hope that helps.

 

[Gazwag]

Conservatory would be better as you might not need planning permission

 

[cliveh27]

I don't know the full rules regarding planning permission. I think as long as half the wall area is glass and the conservatory extends no more than 3m from the main line of the house, then you're OK. Any reputable builder should be able to advise on this.

 

[Tim Over Whelmed]

Be very, very careful. Be clear about the specification including sockets (and locations) insulation, method of wall build etc etc. When you've done that 100% screwed down, get a price for the job not day rates etc and, if necessary YOU buy all the building materials
I

 

[deletebeepbeepbeep]

Conservatory would be better as you might not need planning permission

In some cases you don't need planning permission for extensions, as long as its not a listed building or in a Conservation Area you can extend your house by 15% (up to max 115 cm) of the original size and is no higher then highest part of original.

 

[s5.bha]

If you would like a quote (and agree, best too get 3 at least) then PM me with a contact number and I will get my boss to give you a ring and he can arrange to pop round.

regards Shaun.

 

[withdeanwombat]

Mine cost six grand,but it included both tent poles and a groundsheet.

 

[Bold Seagull]

This can be a useful tool:
http://www.whatprice.co.uk/building/house.html

click on house extension and you can enter particulars to build up a price.

You can check if you need planning permission here:
Planning Portal - Do You Need Permission?

While an architect can seem like an additional cost, by drawing every thing out and itemising a 'schedule of works', you can go out to tender confident that each builder is pricing for exactly what is required and not making assumptions that they later claim requires more money. You'll probably also need a structural engineer to do a few calculations for building control. Adding 10% of the construction cost for professional fees, and local authority application charges is probably reasonable.

 

[HAILSHAM SEAGULL]

As long as there is a physical barrier,eg; a door leading into the conservatory then planning permission is not required, provided you do not exceed 3m projection for a semi detatched or 4m for a detatched.
There are instances when you will however, eg conservation area, areas where PD rights have been removed(permitted developement), height to the eaves if you are on a steep slope etc.
Also if it has a glass or polycarbonate roof, it is a conservatory, so building regs are not required.
I am a conservatory surveyor and carry out surveys for numerous trade supply outlets, if you need more assistance, PM me.
As a guide, a specialist window/conservatory co's will charge £1000/£1500 per square metre to build and fit a conservatory, depending on design and specification, and site conditions.

 

[cliveh27]

Totally agree with the posts regarding plans. Before you get the quotes, think about what power points you want, lighting, heating, flooring etc. Think about which direction the conservatory will face and how hot/cold it will get at different times of day. What sort of blinds will you want on the windows (including the roof). Ventilation? Think also about any drains that are currently running down the outside wall that may need to be blocked in or diverted. Think about any sewers that run along the back of the house. When you have got all your quotes, don't necessarily take the cheapest, but think about which builder has considered the whole job properly.

 

[drew]

Sorry but 4 foot by 7 foot! Is that not just a porch on the back of the house?

 

[BensGrandad]

Sorry but 4 foot by 7 foot! Is that not just a porch on the back of the house?

That was my first raection sounds like a diy plastic corrugated sheet jobby. Surely if spending money to have one built it is better to go the maximum size you can afford and would possibly need in the future.

 

[Gully]

That was my first raection sounds like a diy plastic corrugated sheet jobby. Surely if spending money to have one built it is better to go the maximum size you can afford and would possibly need in the future.

I would also go with that, not only should it be something in keeping with your home, but it should also add value to the property that exceeds what you spend.

My house was extended some years ago, before I bought it, to add a large utility room, incorporating a shower and toilet. This was done in a way that the room could also be used as a dining/sun room as it has large double doors out to the garden. There is no doubt that that type of extension adds to the property and was definitely an attraction, making it stand out from the competition, when I looked at the place.

 

[DT Withdean]

The often quoted £1,000 to £1,500 psm, I know through experience, may be on the low side due to:

- South East Englands tradesmen prices are higher.
- Modern insulation, building reg's
- Are you excavating into an upslope? Plant hire, time & waste charges.
- Skip costs have rocketed due to Gov't/Council tipping waste charges.
- Soakaway excavation reg's, Radon report, Building control fees, architect, structural engineer
- Import prices of some materials, kitchen appliances, have rocketed due to weak £.

My gut feeling is that the £1,000 to £1,500 psm is for the basic shell on very old prices.

You need to budget realistically, think of every aspect, and then add 10%.

But may well be worth it, to get extra space and a layout/finish you love.

 

[piersa]

i just had a look at an extension being built. Would have cost about £2500 psm. That was with a pitched roof. Bulders seem to over price small jobs. Get a quote from someone who has already been used by someone you know. Far too many cowboys out there.

 

[Bold Seagull]

i just had a look at an extension being built. Would have cost about £2500 psm. That was with a pitched roof. Bulders seem to over price small jobs. Get a quote from someone who has already been used by someone you know. Far too many cowboys out there.

Depends on what is in the extension I suppose. I'd have to assume you had proposed a kitchen or some specialist b-fold doors or something in there, otherwise that is simply astronomical for a typical extension.