Extension Costs Estimate v Real Life

bernice_31

We are embarking on a very exciting journey; selling up (and hopefully clearing our debts) and moving in with the in-laws, extending their home and creating a lovely place together, more affordable and looking after them in their old age.

However, having never built or extended a home before, I'm not 100% sure how the budgeting of the build works?

I understand that the average cost is about £1k per m2, so if we are doing two storeys, of 6x9m each, that comes to around £110k, give or take.

My question is; is this just solely for the build, or does it assume basic decorating, doors, bath etc? We are going to be saving for a 20% contingency anyway, but I would like to be going in to this with as much information as possible.

(We dont have expensive tastes, everything will be done to a very basic standard!)

Plumber90

That is everything from start to finish.

bernice_31

Finish being ready to move in and live?

System

Tbh I think the 1k figure is out of date now, I would allow 1.5k min, and work on existing buildings is generally more expensive too.
however the best advice if you are on a tight budget is to get as much information together as possible before getting it priced, if there are lots of unknowns it will be easy for the job to eat the contingencies quickly...

Hoof_Hearted

When you get a builder make sure you have contract and stage the payments.

I_have_spoken

Where the costs mount up -

- Fees from selling your own property to be paid to EA
- Council tax while your house is unsold
- Fees to arrange any bridging financing needed to cover the build, then interest payments until the capital is paid-off
- Rental costs for you/in-laws while the build takes place (living on-site is grim and slows work down)
- Legal fees for wills etc. From what you say, you need to be 100% clear on ownership of the extended property. The last thing you want is for the in-laws to go into council care and the whole house being sold to cover costs
- Architect/Designer charges
- Engineers fee for checking major structural work is OK
- Party wall settlements if the extension triggers PW considerations
- Quantity surveyor fees
- Specialists fees, i.e. if a tree has a TPO on it
- Planning application fees
- Labour costs
- Material Costs
- Project management costs
- Rubbish/muck away skip hire

To get realistic quotes from builders, you'll need -

+ A full set of plans/drawings. Do NOT let the jobbing builder design the house!
+ Specifications for fixtures and fittings
+ Details of anything you'll provide yourself and/or do yourself
+ What type of quote you want (fixed price or cost plus)

bernice_31

I_have_spoken wrote: »

- Fees from selling you own property to be paid to EA
)

What is EA?

BoxerfanUK

bernice_31 wrote: »

What is EA?

Estate Agent

muckybutt

Sounds about right 1K per m2

We have just had a 48m2 timber frame extension built which in total came to 17K for the frame and 30K for the erection and build cost, that was just to first fix stage though - I did the ground works and pretty much the whole interior fit out myself which saved us a few grand. Suppose it depends on where you live too.

The frame was up and waterproof in 4 days - brickwork done in 2 and a half weeks - roofed and jointed into existing roof in 1 week - interior 2nd fix done in 3 weeks. In total completed in 8 weeks.

bernice_31

BoxerfanUK wrote: »

Estate Agent

Ahaaaa! Thank you.

I'm planning to go via Purplebricks so hoping only to spend around £1k there.

bernice_31

muckybutt wrote: »

Sounds about right 1K per m2

We have just had a 48m2 timber frame extension built which in total came to 17K for the frame and 30K for the erection and build cost, that was just to first fix stage though - I did the ground works and pretty much the whole interior fit out myself which saved us a few grand. Suppose it depends on where you live too.

The frame was up and waterproof in 4 days - brickwork done in 2 and a half weeks - roofed and jointed into existing roof in 1 week - interior 2nd fix done in 3 weeks. In total completed in 8 weeks.

That's useful to know too. Fingers crossed if we get our place sold in the spring, we can get most of the work done during next summer, as we are going to have to sleep in our camper while the bedrooms are being extended. :T

Is there anywhere I can guesstimate the cost of each room to decorate/fit out/