Extension Costing - How to alter roof

[Muncher]

I'm looking to buy a property at auction as a renovation project.

One option is to refurb it as-is, which we have costed out, allowing a fairly large contingency, taking into account what we think it would sell for it certainly looks like there is an opportunity there.

However, the property is crying out for an extension (it's 2 bedrooms with bathroom downstairs). We have a reasonable idea of what it would sell for as a decent sized 3 bed.

We would be looking to come out by about 3m downstairs and 5m upstairs. (subject to planning)

Now the brickies we have used have suggested ~£7k for groundwork and bricks up to roof height. We would have to replace windows and doors, plaster and plumb the downstairs room entirely in any case.

So that means the roof is probably going to be the major cost of extending. Are there any ways of putting a new roof on the rear, to give that amount of floorspace, without putting a whole new (or flat) roof on?

[herbialfa]

To keep the costs down you could extend between the chimneys out with a hipped roof finish.

Without seeing the floor plans and don't know what that would affect the upstairs layout.

Or depending on the position of the sun, go out on one side only and continue the line of the roof pitch and continue that through.

[Muncher]

Here's the floorplan. Really I'd want to double the size of the upper floor.

[Muncher]

I would also be interested to hear your opinions on costs for the extension which would be ~60-80sqm.

[dirty boy]

I'm doing an extension, paying for it as I go along at the moment.

The one highlighted in green is finished, it's two bedrooms above a garage. The ground dimensions are 6.6m x 3m. Cost was just under £30,000.

The second one highlighted in red is under construction and i've been keeping an accurate breakdown of 'everything'.

I had to move a couple of drains, and am going for a floating floor. Including planning fees etc, it has cost me £4,599.90 to get to where I am now. (poor picture attached)

Included within that is all the blocks, bricks and cement I need, just haven't used yet!

I'd estimate another £6k to get it water tight with a fibreglass roof. Another £5k to add all the finishing touches.

[dirty boy]

sorry, missing pic

[Muncher]

That's useful thanks, to what extent have you done work yourself or used connections to get labour or materials at favourable rates?

Other than the roof and some of the brick work I would be doing the rest of it myself with the help of family who are in various trades.

[dirty boy]

Muncher said:

That's useful thanks, to what extent have you done work yourself or used connections to get labour or materials at favourable rates?

Other than the roof and some of the brick work I would be doing the rest of it myself with the help of family who are in various trades.

shop around for materials, Jewsons, Travis etc, they will and do compete against each other. I've found the local timber merchant is FAR cheaper than any of the big chains too.

With respect to work being done, i've a mate who comes and does a Saturday morning (8 - 2/3pm) for £80 and I labour for him.

I dug out the floor etc, did what I could. Always have the materials ready and laid out so the trades can just get on with doing what they do best.

[Muncher]

Having done a whole load more sums the cost of doing the 2 storey extension is coming in at bang on £20k with a contingency built in. That's based upon the fact that we'd have to do a lot of work on the ground floor in any case. That's for 4.5mx9m, two floors.

[dirty boy]

Muncher said:

Having done a whole load more sums the cost of doing the 2 storey extension is coming in at bang on £20k with a contingency built in. That's based upon the fact that we'd have to do a lot of work on the ground floor in any case. That's for 4.5mx9m, two floors.

If you're doing plenty yourself, I don't see why not.