Garage Conversion

[PiKe]

I have a 2.5x5m attracted garage which I would like to convert into a habitable room.

The garage currently has a combo boiler, washing machine and small chest freezer, there is also a cold tap near the garage door end.

I believe the theory in converting it is to lay joists on the floor and fill the gaps with foam board insulation, then nail ply on to that and then lay whatever flooring I like, similarly on the walls but to use plasterboard instead. Can anyone confirm this is the correct way to go about it?

I wish to change out the garage for upvc patio doors, would I do this before any of the other work?

 

[Maccapacca]

Check your heights out. My neighbours just laid 140mm of insulation in the floor plus ply plus plasterboard rapidly totals not enough head height.

 

[PiKe]

Plenty of height fortunately as it's a step down into the garage.

 

[PiKe]

Double post.

 

[Maccapacca]

Good then think about if you want it to meet building regs. You might want to think about asking someone to draw up some details. General sections that meet bregs if you want it to be considered as habitable space.

 

[bitslice]

Planning regs suggest 150mm between a suspended floor and the concrete.

http://www.planningportal.gov.uk/permission/commonprojects/garageconversion/


I'm assuming you haven't got a big manhole in the middle like mine.

 

[PiKe]

Building control said planning won't be necessary.

How would I start with the floor? Would it need tanking and how would I make up the 120mm difference in floor height between the kitchen and garage?

 

[Maccapacca]

It's all in bitslices link

Solid floor

The existing concrete floor can be used as a base, however a new damp proof membrane (DPM) will need to be introduced. DPMs come in solid or liquid form, the latter being a practicable solution for a garage conversion. Manufacturers will be able to advise. A suitable gauge damp proof membrane (DPM) and thermal insulation must be provided. These can be laid over the sand blinding or on top of the concrete.

 

[Jez]

Pike, one of the biggest lessons I have learnt in building. Get your building regs fees worth from the inspectors.

Get a building notice in with a fee for the works (one off fee includes all inspections and advice, as many site visits as you want in theory), then just use them as your reference for everything, after all, they'll be the ones signing it off.

In this case I would guess that you'll be needing a heavy gauge dpm over the concrete, covered in 50-100 pir insulation, then floating floor or screed over that.