Rough cost of a 2 storey extension? Lessons learnt?

[Karbea]

hello,

We are planning on having a two storey extension, we would need to knock down the current double garage, rebuild and build a bedroom and ensuite on top.

Initially we wouldn't want to spend more than £120k so would think about doing it in stages, if possible?

Has anyone done anything similar?

If so how much did yours cost? And do you have any lessons learnt for us before we start this journey?

Thanks!

[Yorky]

Where in the country are you?

We have just applied for PP for a double storey extension and are hoping it will cost about half that amount, maybe a little more if you include the kitchen and new bathroom fittings!

Why do you need to knock down the garage? Are the foundations inadequate for adding rooms above, and how do you know?

[Karbea]

We are in Buckinghamshire.

Our house is on a slope and the ground below the garage would need to be excavated so that the first floor was at the same height as our current house, if you see what I mean.

I put the size of the extension into an online tool and it came to about £150k but I couldn't specify a double garage which I think would maybe make it cheaper??

[sunnylabsmum]

we are currently 4 months into our rebuild- demolished double garage and have rebuilt double garage + full width utlilty across the back. Above it is 1.5 size of a double garage as we had a chalet roof and in adding on an extension gained lots of roof void space. Upstairs we have 2 double bedrooms each with an ensuite and an office space with double height roof. At the same time we are having a conservatory added to our kitchen and some remodelling downstairs. We had quotes ranging from £170k to £103K and it will come in around that lower end of the budget but does not include the kitchen and bathroom fittings but did include a full house rewire and a new boiler. we are living in the place at the same time and this has been a challenge...currently the builders are finishing the floor in the utility so when they break into the kitchen and do the consevatory I have a washing machine and sink....I have also worked out how to cater for us via a microwave, slow cooker and deep fat fryer whilst I have no kitchen.
The online guide would probably think it is all usable space and so if you had a double garage then it would reduce it a little bit, but not that much I think. We worked out that our total new area was doubling our original space and whilst we orginally thought the extension would cost about £80K we soon realised that we needed to think more of £120K which is what we expect the total all in will come to.
Any lessons learnt-yes- fight for a good design. We had to appeal out PP refusal as we didn;t want their bland extension formula but something better. its fab seeing it emerge from the drawings. Architects and builders do not get onfact. Builders ideas of clearing up are wildly different to yours- it will take longer than you think whatever anyone promises- dust gets everywhere and there is little point in doing more than getting rid of the worst of it- making your mind up over showers, baths, kitchens, tiles etc is easier said than done. Oh and finally build in a contingency element- our neighbours extension last year had to have far deeper foundations because of a pond right near where our extension was to be built...fortnately it didn;t affect us but if it had it would have cost us lots of extra£'s.

[fossil97]

We have done similar, really is 1.5 storey as bedroom has sloping roof. No change out of £100k and that's with a lot of DIY, did not move out. All new kitchen and bathrooms included.

Lessons. Plan carefully, make sure things match up/fit together if you are ordering them in yourself. Don't overestimate what you can do yourself if you have jobs/kids. Check out that "mates" are actually good at their trades before giving them work (sad experience). Go for the builder you think will do a good job, not the cheapest (good experience, he was a diamond and perfectionist).

I wouldn't do it in stages - prolongs the agony!

Have to say that a bedroom the size of a double garage is mega .

[fossil97]

Also we have had our garage designed so it could be converted to a granny flat - hopefully this is insurance against it actually being needed .

[kaytola]

My two storey extension was (gulp) just over £18,000 . It gave us a very large fourth bedroom and a third reception room downstairs which leads onto the patio. Maybe I was just lucky as our builders were fantastic (and cheap). Whole thing took 7 weeks.

[Thinkingof4]

kaytola when was your extension done? £18k is amazingly cheap. We are planning something like that but have been told to expect to pay about £100k. Where are you? I wish I could ship your builder up here! (north east Scotland)

[kaytola]

The extension was done in September/October 2007, so coming up for five years now. I cannot believe some of the prices quoted on here! I must have got a real bargain. I'm in Yorkshire BTW.

[tricot39]

thinkingof4 how far north are you?
I hear the builders of the far north charge something like London prices because they have a captive market!!

[PollyWhittaker]

Wow, Kaytola. I'm in Yorkshire, and I'm expecting mine to cost around £60,000.

[PollyWhittaker]

Sorry. I posted before realising this was a zombie thread.