Center and level the first section after you install the brackets. The door must be level even if the floor isn’t, so use shims under the section to level it. The rubber gasket on the bottom section will fill the gaps created by an unlevel floor. To hold the level in place, tape it to the section. To hold the section in place, lightly toenail a 16d nail into the frame and bend it over the section. Add brackets and rollers before setting them in place and stack one section on top of another, toenailing as you go up.
Test the door balance. A garage door should require only a few pounds of pressure to move it up and down. If springs wear out and lose their resiliency, a power garage door opener may need to work extra hard to lift the door. This can quickly wear out the motor on the opener. Replacing worn-out springs is usually a job for a professional technician.
Door styles - in addition to the styles just mentioned, it is important to also consider additional features such as windows across the top of the door to provide light inside of the garage, the use of steel or wood frames to give decorative doors added security and stability, and insulation which can reduce energy costs in the attached garage by an impressive 15 to 20%; and