Everywhere you look these days people are extolling the virtues of insulation, and with rocketing energy costs, it certainly makes a great deal of sense. But for some parts of the home such as the garage, it is a worthwhile investment.
The first thing to consider is why you would want to insulate your garage. If it forms one of the outer walls of your home, then the wall adjacent to your property may well be worth insulating . Technically this would probably be classified as insulating your home rather than your garage, and there would certainly be benefits to doing this. Every outside wall presents an opportunity for heat to escape and as the sole purpose of insulation is to slow the transfer of heat, then every external wall should be considered for insulation.
Let’s consider a separate garage, one that is not attached to the home. The thing to consider here is what you personally use the garage for. If it is simply a storage room for the excess debris of your life, or for your car to reside in overnight, there is probably little to no benefit of investing in insulation.
Conversely, if you regularly use the garage as a workshop, somewhere that you spend significant periods of time, then that presents an entirely different situation. This may be the perfect reason to insulate the garage, especially when you are spending a lot of time there.
However, and this is important to remember, insulation will only help to slow the heat transfer. So before even considering insulation you need to have some form of heat source, to generate the heat you are trying to retain. This may sound silly, but it is sometimes an oversight with people thinking that good insulation will solve all of the issues.
So in summary, if you spend a lot of time in the garage, then insulating it could be a very good investment. You need to factor in some form of heating, and then consider insulating the walls, ceiling and of course the garage door. Thin metal garage doors will allow heat to flow away very rapidly so you must consider how to square that circle.
In terms of cost, you are probably looking at somewhere in the region of $1500 dollars to fully insulate a garage, walls, ceiling and garage door. This is obviously quite a significant investment, so only you will be able to decide if it is worthwhile for your personal circumstances. And as mentioned above you will still need to have some sort of heating source as well so factor that into the equation.
If you do spend a lot of time in the garage, and also enjoy DIY that it is probably a great project to tackle, and one that will benefit you for years to come.