garage conversion - advice required

Hi guys,

I live in a 3 bed detached with a single garage. House is apporx 15-20 years old

I would like to covert my garage into another room. I am gas fitter by trade and can basically throw my hand to anything so looking for advice on how to do this properly. I will be getting a bricky in to do the brickwork as theyll do a better job than me.

Anyway, garage has a cavity with breeze block internal walls. Im assuming that all I have to really do is the foloowing

1. remove garage door
2. brick up to dpc
3. install screed to level floor
4. get 2 sockets put in and the light switched moved. light already in centre of room
5. putting plumbing in ready for radiator
6. brick up to bottom of new window and install new window
7. dry wall and plaster walls
8. decorate

is this the way it should be done?

just a couple of questions

1. Will i be allowed to build directly onto the concrete 'foundation' at the front of the house where the garge door is? if not, what will they expect me to do here to satisfy building regs

2. The current conrete floor is not level. its currently 140mm below dpc at the back of the garage and 40mm below dpc at the entrace of the garage. Will i be able to just screed straight ontop of this or will they expect insulation/visqueen to be put in

3. Is there anything else i should be aware of? any advice at all greatly appreciated

please guys, im looking for a little advice from some experianced guys or girls

I don't [normally] reply to garage conversion threads, because there are literally loads of these already posted with the very same questions and answers

You might or might not be able to build on the existing slab. It depends what the BCO says

You build a timber floor and insulate or insulate and screed. Insulation will be at least 80mm celotex type, or more if a different type.
40mm is not a lot to play with if you want the floor level with the house

^woody^ said:

I don't [normally] reply to garage conversion threads, because there are literally loads of these already posted with the very same questions and answers

You might or might not be able to build on the existing slab. It depends what the BCO says

You build a timber floor and insulate or insulate and screed. Insulation will be at least 80mm celotex type, or more if a different type.
40mm is not a lot to play with if you want the floor level with the house

Click to expand...

Well if you don't normally reply to these threads, thankyou for replying to mine. Much appreciated

I kind of had an idea that the bco may want new foundations putting in in order to brick up the front but I didn't realise I would have to put insulation in the floor when I make it level with the existing floor level. I assumed that when the house was built, they would have added the insulation to the floor in the garage just like the rest of the house.


If I've only got 40mm at the front of the garage, how would I be able to get 80mm celotex and screed over the top?

If I was to get someone in to complete the whole job, how could they possibly quote this job as they won't know how the bco will want them to do the job so extra costs maybe incured. Who's responsibly are these Extra costs?

If you have plans drawn then the builder builds and quotes to the plans.

If you do this on a building notice (as would be normal) then your builder should quote for a "most likely" scenario based on his experience - and tell you what this would be. Then, if the BCO wants changes you will pay for those - or deduct the costs if cheaper.

Make sure in any quote you get a daywork rate or a basis for pricing variations to the work

House builders don't tend to insulate below garages when they build new houses

If you only have 40mm to play with, then you need to discuss this with the BCO. There is a "reasonable provision" clause in Part L ( the b/regs which deal with insulation) which you may be able to mention, which will allow you to use less insulation in some circumstances