Garage Conversion - Floor level is 4 feet higher than house

[Dtown59]

Hi this is my first post and I'm looking for ideas on my planned garage conversion.

The garage floor is about 4 ft higher than the house - underneath the garage is a basement/cellar. The garage is adjoined to the house via a conservatory.

I'd like to lower the garage floor to the level of the house and then knock through the adjoining wall into the conservatory - giving me a very large living space.

What type of professional can advise me on structural implications of removing the concrete garage floor and replacing this with joists set 4 feet lower down?

If structural integrity will be maintained, How do I set about removing the concrete floor of the garage?

Some guideline thinking and help will be appreciated

cheers
Dtown59

 

[Static]

Structural engineer can give some guidance of feasibility and construction methods for lower/replacing the floor..

 

[Blagard]

That is likely to be a major job, and definately one for a structural engineer to guide you on.

Think about a split level arrangement as well, using the existing floor levels.

 

[^woody^]

I dont think this requires a structural engineer

The existing floor is unlikely to be giving any structural support to the walls (unless you have some funky designed house) and it will just be "a floor".

You should therefore be able to lower it and replace with timber.

Any competent designer should be able to do the design work

 

[Blagard]

I see where ^woody^ is coming from. He might be right to.

What type of concrete floor is it ? There are a multitude of ways of building a floor in concrete including perhaps what I am guessing ^woody^ is thinking of. A concrete beam and block floor? Have a look at the underside if you need to.

 

[macadonald]

At 4 feet higher, surely the garage foundations are higher than your house floor? Not sure what the lie of you land is like..

 

[Static]

The garage floor is about 4 ft higher than the house - underneath the garage is a basement/cellar. The garage is adjoined to the house via a conservatory.

Foundations would probably be quite low

 

[JohnD]

the basement won't be very comfortable when you lower the floor above it.

Are you on a hill? How old is the house?