Extension on a budget

Joined
15 Apr 2005
Messages
16,510
Reaction score
265
Location
Yorkshire
Country
United Kingdom
A couple of years ago we had plans drawn up for a full width single storey 6.5x2.4m extension with vaulted ceiling, 3 sky lights, and full knock through into existing full width kitchen. Quotes came back as high as £40k (may have included kitchen). This was under permitted development.

We couldnt afford any of the quotes we got. We decided to refurbish what we had instead at a total cost of around £8k, which got us a new concrete slab, replastered walls, new ceiling, new back door and new diy kitchen.

So a couple of years later we realise the kitchen isnt really big enough for us and, I am thinking about how we could afford an extension, given the original proposal was fairly high spec!

First thing that comes to mind is I could dig the foundations myself and prepare the site with drains etc. The extension wouldnt be full width either, as this way we avoid moving a water meter and manhole. It would project 3.7m and be 3.2m wide.

I would have the contractor do founds and concrete floor, and build the walls. Under PD could I have block walls rendered externally (ie different to the brick house)? And would this be cheaper than brick walls? Regardless of the cost i like the look of this contrast.

The electrics and plumbing I can take care of myself (i am aware of legalities here, I am a mature electrical apprentice).

Then theres the roof. I consider myself competent to frame out a flat roof, surface it with a rubber epdm product and build two upstands for two roof windows and fit these and rainwater products.

The contractor would then return to knock through, fit a set of bifolds and plaster, then hand over the project to me for decorating etc.

Does this sound feasible? Is there anything you would or wouldnt do that i have suggested? Am i likely to get a contractor on board with this scheme of work? I am in rotherham,
 
Sponsored Links
At a high level, yes you can approach it that way. Each step will involve many complications and challenges so you need to be able to get your head around the project as a whole, and take responsibility for all the dependencies and building regs compliance.
Also the first set of contractors (bricky) are likely to be different to the second (bi fold door fitters) and 3rd (plasterers) unless you’ve already got someone on board who can cover all of it
 
Thanks for your reply, you are spot on, i am willing to take responsibility for the whole project including legal and planning and building control and managing various contractors. It looks like under PD you have to use similar materials to the existing building so white render would be out of the question. A house on my street recently had to submit an alteration to plans because they used white render instead of the approved brickwork on the original plans. Then again, what will cost more, building it in brick or submitting full plans for white render?
 
No idea about “full plans for white render” but I doubt you’ll save that much over a small area, yeah a few days less for the bricky, but then the cost of rendering it, painting it, ongoing maintenance of render. Might be worth running the render thing by your local planning dept, mine offer a free 10min chat where they can give generic advice
 
Sponsored Links
Thanks for your reply, you are spot on, i am willing to take responsibility for the whole project including legal and planning and building control and managing various contractors. It looks like under PD you have to use similar materials to the existing building so white render would be out of the question. A house on my street recently had to submit an alteration to plans because they used white render instead of the approved brickwork on the original plans. Then again, what will cost more, building it in brick or submitting full plans for white render?

Build in brick, save on full planning permission.

Cost of face brickwork will be less than cost of blocks plus render plus paint

I know you like the idea of render but Im thinking cost is your top priority
 
Rendered walls cost more per m2 to build, have regular maintenance costs, and have limited life.

Only consider render if you don't know a good bricklayer, but do know a good plasterer. And you are moving within two years time.
 
Thanks for the help guys really appreciate it. We're a way off building anything yet but it's good to have a bit of a clue about these things. I know a builder who does bits of everything (he did all the work in the kitchen) so I was thinking of using him for the bits of this I can't do but might consider separate trades instead (the company I work for employes all trades so I can probably find somebody there who will do side work).

Thinking about it, the only thing stopping me doing the concreting is getting enough man power and barrows on the day! Then I only need a bricky and a spread. I might spread the word on Facebook when the time gets close. Fire up the barbie (in the front garden) for after the work is done.

I'm going to be fitting a low profile wet underfloor heating system throughout the ground floor when this is done too. Can't wait.
 
It may vary by area, and you may get caught on the minimum order amount (my company was 3m) but you'll probably struggle to beat barrow mix - and the only labour you'll need is someone on the other end of the tamp when you do the slab.
 
We didn't go as far as you but i did all the water/heating/electrics for our extension and the architect didn't like the idea at all from a contract point of view, but we still got 6 quotes.
In the end the builder didn't read the paperwork and thought we were also doing the external decoration and drainage+gas pipework which caused a lot of trouble, but i think as long as it's really clear who is doing what you would be ok. Just watch nothing falls between the gaps.
But it is a great way to economise, focus on trades where the labour is expensive but the materials are cheap!
 
We didn't go as far as you but i did all the water/heating/electrics for our extension and the architect didn't like the idea at all from a contract point of view,
Not sure we're using an architect. We did have one to draw up plans for the original extension but the only thing I need doing for the new extension is a different (smaller) steel calc for the knock through. Is this strictly necessary? Could I just use the same steel as originally worked out just shorter?

In terms of getting contractors on board and specs, is it really necessary to have a complete architect plan? As long as I have a diagram and thorough spec sheet. Then I can get a brickie for example and ask him to build insulated cavity walls x high with a big gap for doors x by y.
 
You need an architect mostly for the design of the use of the space, if you know what you want somehow then you can just do it directly with the relevant professionals.
 
"Budget extension" and 'using lots of individual trades' is a oxymoron.

It only works if you either know or trust all the trades to do a high quality job at good rates, and to work together not in isolation. Otherwise, they all want their pound of flesh and you end up paying over the odds to give it to them.
 
we are halfway through an extension similar to yours. We went single story 7x5.5m, with a second story on top of 5.5x2.5m

I am a maintenance engineer with (what I would say are) good diy skills, live in Kent.

these are the bits we have done ourselves after lots of stress and research!!

Did the underground drainage (inc new manhole),
joists and warm flat roof,
concrete slab,
Install new steel beams and supports

we plan on doing the pitched second story roof, then all the decorating, plastering, plumbing, electrics installing bifolds etc ourselves.

Expenses to others up to now have been
Brickie 6k
Epdm flat roof contractor 1k
Expect render 3k
New beam in attic to support ridge beam 3k

at the moment we are close to 30k into it (from initial plans)
Just got the steel beam in existing attic, pitched roof and rendering before the shell is complete. so expecting shell for 35k
stupidly didn’t get quotes for a contractor to do the full shell but Going on prices people have had around us expect it to have been a lot more.

Hope to get all done minus the kitchen for a total of 50k (might be a bit optimistic)

Hope this helps you a bit on prices and feasibility of what can be done as we had no idea starting out!!
 
Also, if you are going to do parts of the actual building work yourself pay extra to get good plans drawn up, ones which you can understand and follow.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top