Measure the land you have available and write down the total length and width of the area. Use a spirit level to ensure that the proposed site is flat and even. Look out for any drain covers as these may have to be moved, which can be expensive. Determine if the surface is suitable for a garage structure. If you need to lay a concrete base, you must factor this into your plans.
Plot the dimensions of the garage on graph paper. You can use each square to represent 1 foot to get an idea of the maximum size garage you can fit in the space. Determine if the maximum size of garage you can build is large enough to accommodate the car. Measure the width of your car; remember to allow for enough space so that you can get in and out of the vehicle.
Next, make a more detailed plan. Use the graph paper again, but this time use four squares to represent one foot. Mark where you would like windows, access doors and what type of main door you want. Depending on the size of the garage, you can choose different roof types, too. Use a free online tool that can help determine the roof design that is best suited for the size of your garage. A flat roof may be fine for a smaller garage, but if you are designing something more grand, you may need a hip or gable roof.
Make a three-dimensional drawing of your garage using a free design tool that can be downloaded to your computer. This can help you visualize and try different layouts of your garage before you purchase materials.
Ask a construction firm to give you an estimate of cost to build the garage as shown in your plan. They may point out errors in your design. Ask for a breakdown of the cost that includes materials. This will show you exactly what you need to get the garage completed.