If your house was not built with a garage attached you can do it yourself with no trouble once you know these facts.
The first step in any project of this scope is to understand what skills you need to know how to build a garage. Things like plumbing and wiring should be left to the professionals but you will be able to do the basic construction yourself. One thing is for sure though, you will be able to attach the wall protector yourself.
You then need to get a permit for the build from your local council. Before you start the build you will need to make sure that your plans have been approved by the local authority otherwise you might be breaching regulations. If you are using professionals to help you build the car storage unit then they will be able to put you in touch with the right people for this.
Measure and level the ground on which your garage will sit. The bottom should be at least eight inches below the planned finished level to allow for gravel to be placed before concrete is poured for the floor. The footer is next on the list and it should be below the frost line of your climate. If you know how to build a garage you can either lay three or four layers of cement blocks on top of the footer, or use what is termed a floating slab for the floor, meaning that after the footer is in place, the concrete is poured and allowed to become part of the side wall.
Sidewalls can be attached to the top plate, attached to the concrete blocks of the wall, or directly to the floor if using a floating slab, once a thin vapour barrier has been placed between the floor and the wood. Learning how to build a garage also requires knowledge of reading the plans. You should also make sure that you leave space in the walls for the door and any windows you might want depending on your garage style.
If you are looking for something easier you can get kits from your local hardware store that has all the materials and tools you will need included and these can be put together simply.