DEAR TIM: My single-car overhead garage door is in bad shape and I have a few vacations days I need to use up. I have survived many a Christmas Eve assembling complicated toys for my kids, so I think I can assemble a garage door. Have you ever installed one? Was the task too daunting? If you think I can do it, what tips can you share? Brad G., Kiawah Island, SC

DEAR BRAD: It's a very good thing you are a veteran of assembling toys that have lots of steps and parts, as you are going to be faced with the same thing as you work on your new garage door. I have installed overhead garage doors myself and have watched many a professional install them on my own jobs.

It was a hot day as I was winding the worm-drive gear that put just the right amount of tension on the spring just over and behind my head. The cordless drill was the perfect tool for this job. PHOTO BY: Kathy Carter

Some doors are far more difficult to work with than others and some garage-door-spring assemblies are very dangerous to work with. But if you select a lightweight door with a do-it-yourself friendly spring mechanism, I feel you will only need one vacation day to have a gorgeous maintenance-free garage door on your home.

When you first look at all of the parts and pieces that comprise a garage door, you can be quickly intimidated. The large pieces of metal track, hinges, rollers, springs, cables, handles, struts, door panels and a mountain of nuts, bolts and screws are enough to take the breath away from a seasoned weekend warrior who loves home improvement projects. It is a known fact that the garage door is the largest mechanical device found in the average home. So it is perfectly normal to experience a degree of anxiety when you first start the project.

But some large garage-door manufacturers have responded and now make very user-friendly door kits. There are still quite a few parts to assemble, but if you read and comprehend instructions, you will succeed. The first tip I have is to simply read the instruction manual once or twice before starting the project. Get familiar with the terms, the hardware and the entire parts list before you even think about removing your existing door.

In your case, perhaps the most critical aspect of the job is removing your existing door. I would highly recommend that you hire a professional to help you with this one aspect. You can get critically injured by the powerful springs that are part of your current garage door. When a garage door is in the closed position, the springs are under tension and are like loaded weapons. Do NOT cut any cables and do NOT try to take apart the spring yourself.

Once the old door is disassembled and out of the way, inspect the wood framing around the garage door opening. Make sure it is in good condition and there is no wood rot. Replace any rotten wood. The garage door track must be bolted to solid wood.

For the door to operate smoothly, the door must be level and the bottoms of the tracks must be level and parallel. It is very important for the first section of the garage door to be perfectly level. If the door you install is a wooden one, scribe the door and cut or sand the bottom of the door so it conforms with the shape of the garage floor. Since all other sections of the door stack on top of the first section, you can see why it is so critical to get the first section perfect.

Be sure to use approved hardware supplied by the garage door manufacturer. Pay close attention to the bottom brackets that attach to the bottom corners of the first section. These brackets must be securely fastened to the door. Do not strip these bolts by over tightening them. Remember, the cables that lift the door attach to these brackets. The brackets are subjected to enormous lifting forces and can rip out of the door and become missiles if not attached properly.

Single-wide garage doors are often the easiest to install. As garage doors get wider the sections get increasingly heavier. The final weight of a garage door, once assembled with all hardware can easily be 400 pounds or more.

This is why it is so critical to ensure the overhead track is securely supported and in perfect alignment. If the door starts to go up and the track falls or the door comes out of the track, it can fall. Believe me, garage doors have fallen from the track and hurt both people and anything that was under the falling door.

Pay particular attention to the instructions about proper spring adjustment. Most door springs are perfectly adjusted if the door does not open or close when it is halfway open. You should be able to lift the door to the halfway open position and it will just stay there without opening or closing.