Heating Your Garage or Shop
Unit Heaters - These hanging heaters utilize a fan to move and heat the air. There are models for natural gas or propane as well as electric models. Unit heaters are less expensive than radiant heaters and are available in sealed combustion models. These are great for garages or warehouses where you want to maintain a constant temperature.
www.lennox.com/products/heating-cooling/garage-heaters
Radiant Tube Heaters - These gas fired heaters heat a long tube that is surrounded by reflectors. Radiant heaters heat objects like the sun. So they warm the concrete floor, tools and you. This provides a few advantages; the space is heated quicker and by heating the objects it is more comfortable and if you need to open the shop door the heat recovers quickly because the heat is in the objects not just the air. These heaters are more expensive than unit heaters and can take more time to install. They are available in sealed combustion models. Ceiling height is important for clearances above what it heats, so that needs to be checked out. These are great for shops that you work in because they are more comfortable.
www.reznorhvac.com/en/na/gas-radiant
Pellet Stoves - If you don't have or want to use gas and you don't need the space to be heated 24/7 then a pellet stove can be an option for smaller shops. They can vent out the side wall or the roof and can run for hours without needing tending. It can take hours to get the shop heated from scratch and pellet stoves will require cleaning. A stove will need to be installed on a pedestal so it is at least 18" off the floor.
http://enviro.com/products/catalogue/?f=Pellet&t=FS
Wood Stoves - Same concept as pellet stoves but larger models can heat a bigger shop. It will require more tending and the flue needs to go through the roof.
www.lopistoves.com/productselect.aspx?fuel=wood-stove
Well, I hope that helps. We are happy to discuss or look at your shop and there is no charge for our consultations and quotes.