Are extensions cost effective.

[CaptainComedy]

In 5 years, I*will either be planning*an extension or moving home, I want a rear extension on the house to link to the garage, and convert that into a kitchen, it will add a lot of*floor space (garage is a large double and the extension would be 21ft x 12ft).

That said we'll be doing most of the work, unless it needs to be done by a certified tradesman.

 

[Stretch]

In 5 years, I*will either be planning*an extension or moving home, I want a rear extension on the house to link to the garage, and convert that into a kitchen, it will add a lot of*floor space (garage is a large double and the extension would be 21ft x 12ft).

That said we'll be doing most of the work, unless it needs to be done by a certified tradesman.

How much would you expect it to cost doing the work yourself?

 

[billybob89]

May I add the cost of labour and materials is probably at a all time high hence the quotes your being provided. Of course these are governed by the market conditions at present. A loft conversion and a wrap around single storey extension are two very different things. I would normally say a loft conversion is used to give you extra bedrooms and a bathroom etc. Whilst a single storey extension is typically to extend your kitchen and living space.

First really think about why you want to extend and what new spaces you want to create.

 

[the_r_sole]

Can I ask what you do for work?
.

Architect.
Tbh there's not really an economy of scale with an extension, it's not really going to be big enough to get any real savings. There will be ways to save money in the detail but getting below 2k per m2 needs careful decisions.
If you have tested the local market with a few contractors then you know what it costs (provided you have given the same, detailed information to all the people quoting).
We have seen a huge increase in costs over the last few years, building materials have got more expensive, labour has got more expensive and building regs have become more onerous.
People generally don't extend to add value to their property, they extend to get what they want from it, it's very rare that someone will get a house that exactly fits their needs for more than a few years, sometimes it's easier to extend than find a new house - also 70m2 is huge, I can't think of any extension I've done which was that big, one I got permission for around that size the client levelled the house and built a whole new house!
I am willing to bet that you could get your house really working for you with a lot less than adding 70m2 (and increase the value more)

 

[Stretch]

I could certainly do some trimming on the size.

Is the £2k m2 typical inc/ex VAT, and what finish would that include, flooring, skylights, fixtures, plumbing, heating?

 

[the_r_sole]

Normally all the pricing will exclude vat, 2k per m2 should give you a good standard of finish - should include flooring fixtures and skylights etc but within reason, contractors will price on the cheapest so you really want to get those things specced up fully before pricing, same with tiling and sanitaryware then at least you can take some bits out or reduce the spec if the price comes back too high...

 

[CaptainComedy]

How much would you expect it to cost doing the work yourself?

tbh maybe more than 20k, even though we'll be doing the foundations, the walls, tiling, plastering etc, I won't feel comfortable doing the roofing, and we'll need a plumber to move plumbing into garage/new kitchen area, we'll also need an RSJ going from almost the width of the house, which in turn will require an architect and planning permission.... then there's the electrics and gas to think about.

so it won't becheap, but it will be cheaper than moving / getting it all done professionally.

 

[Glaucus]

they are often cost effective, assuming you like where you live and its just a size issue.

moving, you have so many costs
stamp duty which on your property of 315k is what just under 6k
council tax
legal fees and mortgage fees which can easily add another couple of grand
cost of actually moving, which really depends how much stuff you have.
then the cost of re decorating, assuming you've redecorate the rest of the house and have furniture that fits and is nice, this could be a huge cost that some don't think about

 

[platypus]

I'm in the process of mulling over some fairly substantial alternation to my home, which is currently a 3 bed 1930s semi.

However, the build costs are much higher than I anticipated before I started my investigations. I've had several quotes for a loft conversion, which have all come in around the £55k mark. I have also been doing some rough calculations for a wrap around ground floor extension, using a crude £2k per sq meter, and the costs are fairly eye watering.

Many of the houses on my road are larger/more expensive than mine, and/or have been extended in some way. So it's not like there's a absolute ceiling price for the area.

But looking at the recent sold prices, I just don't really see how the works pays for itself or why anyone bothers with extensions?

Property is expensive in the are too. I was expecting the work to add more value than it cost.

Interesting, perhaps we should talk. We're planning to substantially extended a 1930s 3 bed semi. Two storeys to the side, and loft as well.

What area are you looking at? No need to be too specific so I don't turn up and stalk you, but our architect (measuring up today in fact) told us to expect £1,500/sqm as an average price in Cambridge. We're considering hiring builders from "oop norf" to come down and do the work, putting them up in a b&b or similar for the duration. If we can get them down to £1k/sqm it'll be worth it.

We were also told around £30-40k for our loft extension, but it might well be because we've a different roof/other factors.

Why not move? Well due to my wifes employment situation we couldn't get a mortgage for a 4/5 bed house. On my salary however, we could get a mortgage that gives us the money to do the work to an existing 3bed house .

We'll also just about break even I reckon, if we get ALL the work done we want, given house prices for the area. If we don't, well we're planning on being here for quite a while (sadly), so it doesn't really matter too much.

 

[platypus]

It's difficult to understand why anyone builds houses.

Because you make a fortune doing so .

 

[covenantuk]

Seriously. Paring a builder down to £1k sq/m you're asking for trouble. Why would you want to take that risk if you know you're staying in the house long term?

If an architect tells you to expct £1500 sq/m then that's going to the low end regarding spec and quality of work unless you project-manage it yourself.

 

[platypus]

Because its average for Cambridge, not the rest of the normal* world.

We're not paring a builder down to that price, we're looking for builders who might charge less because they are not from here. We're also not going to choose a builder who's existing work we can't look at and see is of an acceptable standard. If it doesn't work, we'll bend over and take it like everyone else has to here. Along with the ridiculous wait times.



*as normal as oop norf can be.

 

[FTM]

I have just extended as well

for me it wasnt just the cost of the extension..we have done a lot of work on the rest of the house to get it the way we wanted, bathroom kitchen etc

moving house means starting again..and so its not just the cost of a move and a new house.

 

[the_r_sole]

Because its average for Cambridge, not the rest of the normal* world.

We're not paring a builder down to that price, we're looking for builders who might charge less because they are not from here. We're also not going to choose a builder who's existing work we can't look at and see is of an acceptable standard. If it doesn't work, we'll bend over and take it like everyone else has to here. Along with the ridiculous wait times.



*as normal as oop norf can be.

Tbh, importing workers from elsewhere just means your prelims will be higher - to get a 1500 per m2 down to 1k and expect a team of people to pay for accommodation you are not going to end up with a decent end product.
Having worked throughout the UK in the last 10 years I don't think I've had any extension finished for this magical 1k per m2 figure - a couple of new builds I've done have come close but unless you are doing a lot of donkey work yourself 1k per m2 isn't achievable for any sort of quality, builders might tell you that price but just wait for the extras...

 

[platypus]

Well I'm happy to do a lot of the donkey work, but good to know.

 

[Stretch]

Interesting, perhaps we should talk. We're planning to substantially extended a 1930s 3 bed semi. Two storeys to the side, and loft as well.

What area are you looking at? No need to be too specific so I don't turn up and stalk you, but our architect (measuring up today in fact) told us to expect £1,500/sqm as an average price in Cambridge. We're considering hiring builders from "oop norf" to come down and do the work, putting them up in a b&b or similar for the duration. If we can get them down to £1k/sqm it'll be worth it.

I'd be very interesting to see how you fair finding tradesman. Most of the local builders are very busy right now, and typically have a nine month waiting list.

I currently only have plans for the loft which can be found in the spoiler. I was going to get the loft done first, then consider extending next year. However, the builder can't start work on the loft until September, and my mortgage is up for renewal in September, so I've started to think about borrowing extra cash and getting more work done.

Spoiler

Existing

Proposed

Provide scaffolding including temporary roof
Strip off existing roof complete
Install all necessary steelwork
Supply and fit new roof timbers
Build new dormer complete
Install new floor joists and chipboard including sound insulation
Supply and fit new staircase
Supply and fit 2 x velux roof lights
Supply and fit warm deck roof to dormer
Supply and fit sarnafil roof covering
Renew all fascia, soffit and guttering complete
Felt, batten & tile front elevation and dormer walls
Brick up gable end and render to match
Build internal studwork walls
Supply and fit upvc windows
Install all necessary insulation
Plasterboard and skim all internal surfaces
Fit internal doors and linings
Fit skirting boards and architraves to match existing
Extend existing electrical circuits to include new lighting and sockets
Extend existing heating system
Install en-suite shower room excluding fittings (to be supplied)

What is also included but not listed is fitting underfloor heating in the bathroom.

Installing new fire doors throughout the property up to regs.

Quite a few people have said £1.5-2k per m2 is the going rate, including "the_r_sole" in this thread. Two story is closer to £3.5-4k from what I've read. I'm concerned that if I go to cheap, corners will be cut, and I'll end up paying a lot of money for something I'm not happy with.

I don't know how much going further a field (up north) would save. £1k per m2 sound like a big saving, but is labour really that large a component of the £1.5-2k cost?

I mean decent flooring (tiles, wood) is £100 per m2, It's easy to see how the cost soon mounts up.

We were also told around £30-40k for our loft extension, but it might well be because we've a different roof/other factors.

It would be interesting to hear how my loft compares to what you have planed. Is £30-40k inc VAT?

Why not move? Well due to my wifes employment situation we couldn't get a mortgage for a 4/5 bed house. On my salary however, we could get a mortgage that gives us the money to do the work to an existing 3bed house .

We'll also just about break even I reckon, if we get ALL the work done we want, given house prices for the area. If we don't, well we're planning on being here for quite a while (sadly), so it doesn't really matter too much.

Moving just seems to provide better value, and less stress. Even when you consider the stamp duty and other moving costs.

What areas are you in, roughly speaking? We're CB4.

My wife want to stay, but I'm not overly tied to the area. It's not the quietest place in town, and I'd like to be a bit more central. I'd be very hard pushed to find the space I have currently though, it's also very good for work. I can walk it in 10-15 minutes.

 

[platypus]

CB4 as well...*gulp*. I really do not like it, but...needs must.

£40k all in our architect reckoned, for a dormer on the back, and two rooms plus bathroom.

 

[Stretch]

CB4 as well...*gulp*. I really do not like it, but...needs must.

It's not that bad

I'm intrigued to know now where you could own a 1930s house in CB4 which you would consider so terrible. Clearly Hurst Park/Highworth Avenue are very nice, but I'm guessing you must be towards Kings Hedges Road, Green End Road area?

£40k all in our architect reckoned, for a dormer on the back, and two rooms plus bathroom.

Sounds like I might need to keep looking for a builder...

 

[platypus]

Yes, and its the area coupled with the noise from the A14. The reality of the situation buying a house in Cambridge on only one salary. Even with our large deposit.

 

[the_r_sole]

the price of loft conversions can change massively depending on the existing building - structure, plumbing and fire protection, stair arrangement is where a lot of money can disappear. Using ball park figures for these is very dangerous ime, the only sure way to know the price is to have work out all the detail and have it priced on the exact specification.
for example, if you end up with large steels they not only add the cost of the raw material, you might end up with lifting equipment etc... so if you've just got a basic figure allowed for in your budget your contingency goes very very fast