Go to Jewsons and buy a bundle of 1" x 2" tannalised tile lath, and a few 8 x 4 x 2" (measure up) jablite polystyrene and dry line it out! You will be warmer, quieter and dry. Screw the laths to the walls @400mm centres, put polystyrene between the laths, cover the lot with a damp proof membrane such as visqueen builders polythene, and then dry line it all with 3mm plywood (you can get surplus seconds or damged for about £4 for a 8 x 4) and paint. Cost should be less than £200 for a standard garage size. Remember to always put the DPM on the WARM side of the insulation or you will get condensation!! I have done many buildings like this, it is a permanent cure.and you can work all year round without heating except in the very coldest part of the year, If your ceiling is exposed do that as well, but use glasswool, as it is cheaper (but not as good, you will need at least 4" glasswool to be as good as 2" of jablite) Heating by whatever means costs more every year. Condensation is a pain! INSULATE!