Cost Of A Small Single Story Flat Roof Extension

[maclarencat]

How much would a single story extension cost just for the basic shell including planning and building regs 3m x 5m. There would only be 2 walls needed as it is to join the kitchen and dining room. One window & one door. It is in Yorkshire.

[The Builder]

Mac, I'm afraid that we're not going to be of much help to you here.
There's no such thing as a standard extension. Every one is different.
Yes, I can quantify the materials needed, and the time taken for the build, but that is only a part of the project.

There are so many parameters to consider.
Type of construction
Access
Ground levels
What goes on below ground regarding load-bearing conditions.
Connection to existing building.
"Knock-through" to existing building.
Drainage
Etc etc

I've lost count of the number of times I've been cornered at parties and asked "off the top of your head........... etc".
No guess is ever helpful. In fact, it can land you in it when it turns out to cost more than originally thought.

We can't make it up as we go along. We need some kind of detail and specification from drawings.

If it's any help at all, recently, I priced a similar sized extension from Planning drawings only (no technical spec). The finished article would be around £22,000. That was a no-frills extension.

An experienced local builder would assess most of the parameters listed above with one glance. That's all I can say, I'm afraid.

[maclarencat]

Thank-you anyway