Having been gazumped a couple of months ago I'm back on the house hunting trail and currently considering a 1950s house thats had very little do to it in the last 60 years, other than cavity wall and loft insulation. The house is small, but on a big 1+ acre plot with loads of potential.

Anyway having looked around it over the weekend with the wife we've come to the conclusion that if we double the current size we can make it into a decent home.

So the question is what is currently the best, most efficient (cost, time, insulation etc) building method? Your thought most welcolme.

I'd agree with the knock it down and rebuild philosophy, even if it doesn't sound, on the face of it, to be that green. In reality you are likely to be able to build a new house with lower embodied energy, and with better energy efficiency through life, more easily, and more cheaply, than extending an existing house by that much.

Before you commit best check with the planners, though, just to get a warm feeling about the feasibility of the size increase you're thinking of. Although it's a big plot, the planners usually tend to take more notice of the size in relationship to the surrounding houses.

The thing with knocking down is that you're destroying that most valuable and (expensive to recreate) asset - thermal mass. OK, 50s cav wall construction hasn't all that much mass, even when filed with weak conc, so maybe ...

If newbuilding, think of a 1m thick NE/N/NW wall of cob as 2- or 3-wk duration thermal store, heavily EWI'd and poss insulated internally too, so it doesn't heat the building interior uncontroledly. Then lightweight walls to SW/S/SE, accepting not too much solar gain. Your principal solar gain shd be via v big v low temp collectors piped direct to the solar store wall, optimised for max collection in Dec/Jan, which in turn demands precise study of your local horizon, to see just how much sunpath you actually see in Dec/Jan.

Nice cosy straw bale , timber frame construction, external lime render, line interior walls with unfired clay bricks five or 10 cm thick, finished with lime or clay plaster. Lime Crete floors with under floor heating. Heat store, solar panels, passive solar design taking advantage of solar gain, triple glazing etc etc

Posted By: HalcyonRichardif you apply before you own it - the seller may up the price or decide to do it himself

You could cover that by a pre-agreement with the vendor - maybe agree to offer him a slight premium (modest share of the value windfall) if he agrees to suspend sale to anyone else meanwhile.

Called an "Option to purchase contract". Gives you the right but not the obligation to buy at a fixed price for a limited time period.

In return you either pay the vendor a non-refundable fee for taking it off the market (potentially for a year) or agree to share the increase in value that getting PP for the house/small housing estate would bring.

If you opt for the latter it's important to consider how the share is calculated. For example it would be reasonable to deduct the cost of getting PP, the CIL/S106, the cost of getting services to the site, roads, legal fees etc from the valuation before calculating the share of the profit the vendor gets. Needs to be in the contract.

Just got back from a second viewing and having seen the place for a second time I agree the best way forward would be to knock down and start again.

The seller has a couple of offers on the table and i should know later this week if my offer has been accepted. So it's a waiting game!!

Well its back to square one and the property search thing.

The property I was interested in has been on the market for less than two weeks and the seller had 5 offers.

Last Friday the Eastate Agent called to say, could they have 'last and final offers be Saturday lunch time'. So I put in my full asking price offer and waited. On Monday I got the call to say that someone had offered more than the asking price and thanks for my interest.

Who says the property market is dead!!?

Hi Jonti,
Probaby absolutely right. Two sites I looked at for a self build ended up with 6 terraced houses on one and a block of flats on the other. It's just the economics of profit that do it. It would be interesting to find out the price paid. It should be on here after some months :- http://www.nethouseprices.com/index.php?con=Search-Sold-House-Prices

Richard