Insulating a garage

Now that the weather has turned and temperatures have dropped I've noticed my garage is cold and damp which is making everything else damp.
I'm looking to insulate the brick walls but after some ideas on the best way to do this without losing too much space.

My initial thoughts are to build a timber stud/batons onto the wall, fill with insulation and then plasterboard.
Is there any issue with drilling and screwing to the brickwork and what sort of thickness do the batons need to be to be able to get enough insulation?

If the garage is not heated, insulation won't make any difference.

Ventilation would be a better solution to reduce dampness.

And just insulating walls is a waste of time if the floor and ceiling are not also done.

That's a fair point about the ventilation.
What' s the best way to introduce ventilation as well?

I plan to do the ceiling but not sure what I can do about the concrete floor?

It seems like your converting the garage then, and there are loads of the threads here on that.

If it's just ventilation you want, then two or four airbricks on opposite walls will do, or a single humidistat controlled fan.

I'm not necessarily converting my garage but just trying to prevent it getting so cold and damp in the winter so it does't ruin all my tools and other things stored in there.

Any recommendations on insulation thickness and types?

Being cold shouldn't be a problem. Unless you have some heat source inside it, it will always be close to the average outside temperature regardless of what insulation it has. Heating it is likely to make corrosion problems worse since rusting is a chemical reaction and slows down with colder temperatures. The ideal conditions for storing tools etc would be cold and dry. To achieve that you want to minimise ways for moisture to enter the building (make sure the floors and walls are damp proof and no rain can get in) and ensure plenty of air flow. Even so you will always get some condensation just due to air temperatures varying through the day, you just need to ensure there's enough ventilation to get rid of it quickly.