If you were insulating a new garage you wouldn't just leave one wall un-insulated, so why wouldn't you insulate the door? The doors of a garage make up almost a whole wall and they need insulation as much as a wall, more in fact. When the sun beats down upon the door the metal absorbs and radiates the heat into the interior of the garage.Even if you have an insulated door you still have radiant heat warming up your garage. That is why you should install reflective insulation on your garage door. If you want to keep your garage cool in the summer you don’t need any special tools or training. Adding reflective insulation to garage door is a simple DIY project that can be done in a four easy steps.Step 1 How to Adhere Radiant Foil to Garage DoorStart with the bottom half of the door by attaching double sided tape to all vertical and horizontal framework of the door. Once the tape is installed you can remove the paper lining to expose the exterior adhesive. Step 2 Applying Reflective InsulationRoll the insulation horizontally across the door. Be sure to keep thereflective insulation tight and press against the tape as you unroll. It is a good idea to enlist the help of a friend or neighbor to help with this stage. Once you have reached the edge of the door cut the insulation with a utility knife. As always use extreme caution when working with knives.Step 3 TrimTrim around door hinges and cut insulation to create a seam where the door panels meet. This will keep the insulation from buckling while the door is in operation.Step 4 RepeatRepeat the previous three steps on the top half of the door.ConclusionInsulating your garage door is as easy as that! Now that you know how install garage door insulation you can make your garage a space that is more comfortable and efficient.