Building extension to garage brick wall

[JP_]

One thing that I am trying to decide, is do I build a rear extension of 3 walls, or connect one wall to the garage. The garage is brick with a pitched roof, and is pretty much in line with the house and set back about 1m (room for a gate). I have access on the other side - about 2m on the side of the house.

So, I was thinking, why not connect to the garage? I assume that this will be much cheaper, as about 5m less foundations and brick wall.

For speed of build I am seriously considering SIPs with flat roof (maybe zinc roof). Left wall will be solid, back wall mostly glass. Although, if SIPs quote is silly, will go bricks, blocks and good insulation inbetween.

Just wondering, will a quote be a lot less if using the outside of the garage wall as the inside of my extension. Are there any complex issues that may arise?

 

[noseall]

Just wondering, will a quote be a lot less if using the outside of the garage wall as the inside of my extension. Are there any complex issues that may arise?

Depends how well the garage brickwork courses-in with the house and if the brickwork is level, whether the foundations of said garage are adequate or would need underpinning and look at whether there is the need for any windows/doors etc required in said wall, in terms of whether demolition would be more practical option.


We had to take down the back end of a garage recently because it was so far out of plumb, as part of a garage conversion/overbuild. Oh, and it was in twist too.

 

[JP_]

Thanks. Garage was built at same time as house in 2002 by Barratts. All looks solid, and house foundations are 1.5m. I am sure it would be the same.