Extension over existing garage

[Emily Douglas]

Hi, we are in the planning stages of a 1st floor extension.

The house is 1960s and has an existing ground floor kitchen extension. The planned extension will be over the garage, utility room and kitchen. Our main issue is that the existing garage wall is only single skin without appropriate foundations so is therefore not weight bearing. Our choices are to underpin the front corner of the garage and use a steel structure to support the upper floor and roof (ie leaving the garage wall as is) or to knock down the garage wall, do the groundwork and rebuild a double skin wall.

The wall in question is only 3m long as the rest of the upper extension will be over the kitchen extension which was built to support an upper floor.

Could anyone give their views on which route they would recommend or what sort of things to take into consideration?

Thanks,

Emily

 

[Notch7]

Could anyone give their views on which route they would recommend or what sort of things to take into consideration?

the decision will probably be cost -It wouldnt surprise me if a new wall was cheaper

It rather depends on the overall scheme -if there is other groundworks and a digger and dumper is on site then demolition may be easier.

removing a wall sounds drastic but its easy for a builder. Underpinning and steel work is awkward -you would also need a SE, whereas digging a new foundation and new wall maybe done with the building inspectors approval

 

[Emily Douglas]

Thanks for the feedback. Should have also attached the prelim structural engineer drawings of the potential underpinning.

Spoken to a couple of builders and difficult to get an estimated cost out of them without the full structural drawings. But we can’t get those until we decide which route to go!