Hi folks,

I will shortly be introducing my (detached) garage to the wonders of
modern electricity. Short of trial and error, does anyone know of a
good rule of thumb for deciding how much light and heat is required
per m^2? The garage is only slightly larger than a car, and will be
used for tinkering and storage (but not of cars), and perhaps the odd
bit of tumble-drying.

Part of me wants to say "3 strip lights and a 3kW heater", but I can't
help thinking there must be a more scientific way.

I guess it would be nice to know this in general, since my whole house
appears to be underlit and underheated.

TIA, Rich