Digging foundations

[Carlnorwich]

I am about to convert our integral garage and would like to do as much work as possible myself. The garage door will be removed and the opening bricked up (half way) ready for a new window to be fitted.

- how deep and how wide should the foundations be?
- when I fill the foundations with concrete, how far from the top should I leave it?
- I suppose I will need to hire a cement mixer for the day?
- the new external wall will eventually be rendered. Should the brickie be using bricks or blocks?
- the concrete floor in the garage is no doubt very thick, is there a clever way of breaking it up (i.e angle grinder), or is just a case of sledghammer and sweat?
- is there anything else I should be considering?


Many thanks in advance.

 

[regsmyth]

You may not need any foundations for your "under the window" bit, assuming the garage has it's own foundations. The lintel above the window will transfer the loads into the walls either side anyway.
And if the floor is strong enough for a car, then a low wall and window are unlikely to require any additional support.

Have you notified building control/planning?
They will usually give some pretty good advice about what you plan to do and what they'd expect to see.
What are you converting it into? If a habitable room, you'll need to consider insulation, ventilation, damp proofing etc etc. If you're going to mess with electrics, you'll need to comply with the part P thing.

You should have a go at the wall yourself - use blocks - quicker, cheaper, and since they'll be rendered, you can make a real mess of it and it won't matter.

 

[^woody^]

Build it in a timber frame and render externally. Then no need for any messing about with foundations or hiring a mixer

 

[Carlnorwich]

I have spoken with planning - I'm okay there.

I like the sound of stud rather than all the money/trouble with digging foundations, blockwork etc. I will talk to building control and get their thoughts.

If I do end up going with blocks, you're right, I will give it a go as no one will see the finish.

Thank you very much.