I want to make the garage a more pleasant place to work on my bike and need some unbiased advise.

The garage has a pent roof and is adjoined by another garage with a block wall separating them. Rear wall is single skin brick. Other side wall is single skin brick with the conservatory on the other side.

I already have a partition wall splitting the garage 70/30 with the larger area to the rear and it’s this area I need help with:

1. Interior ceiling, does it need a damp proof layer?

2. Interior walls, what insulation offers the best bang for my buck?

3. Rear wall, the brick is topped by roofing timber (I’d post a picture, but, well, this forum, you know… ) If I fit a window, will it still need a lintel if I take out the bricks up to the timber?

1) My garage has some wooden slats nailed to the rafters to form a ceiling with a gap above to the roof tiles. No damp proof but also lots of air travel so not really needed.

2) Insulation only works if you plan to add heat inside the working area. If it is quite small then consider how long you plan to work in there. If might actually be cheaper to just run the heater for a hour while you are in there rather than insulate everything, spend an hour heating the area and then it stays warm for another hour while you have left.

3) Not sure if you need a lintel above the window for structural reasons but it would be useful to have something to fix the top of the window to. I guess you could screw into the timber but if that moves independently from the wall during windy weather you could start pulling the window/wall apart.

2) insulated plasterboard or build a wooden stud frame and insulate the spaces.

3) yes, a simple steel one would probably be ok, but get professional advice first.

On WCA’s second point, an infrared heater will warm you, not the space.