While you may be able to increase efficiency by replacing the weather stripping at the bottom of an old garage door, the kind of insulation and energy efficient materials used in today’s new doors will make a drastic improvement on your garage’s energy efficiency. Just like the way a new garage door recoups its costs in increased home value, a new door will also quickly pay for itself in energy savings!
I obtained my parts, as described on this page, from American Garage Door Supply Inc. (http://www.americandoorsupply.com/) They may have raised their small-order prices or imposed a minimum order since I ordered from them in 2002 at the prices in my essay above. The Web site offers a free catalog by PDF download or mail. Springs in 2005 were priced at $2.25/lb.
Having a mismatched pair makes it difficult to specify the correct matched-pair replacements. To obtain replacement springs for a mismatched pair, you can either specify the same odd pair, try to calculate the equivalent matched pair sizes, or (this is the best method:) measure an accurate door weight and calculate the right spring size(s) "from scratch". The spring seller should be able to do the calculations from your accurate measurements of weight, height, and drum size; or you can attempt the calculations yourself using my engineering formulas below.

The door and tracks at this stage of the repair are in a minimum-energy condition. This is a good opportunity to work on any hinges, bearings, rollers, cables, or tracks that need tightening, repair, lubrication, or replacement. Again, these parts should be available from the spring source, and should be ordered based on a pre-inspection. Home-improvement stores carry some of these parts, but the type and quality may not be the best.
Extremely straightforward and efficient estimating and installation process. We purchased a Clopay sectional steel garage door for our double garage that works flawlessly with our existing door operator. The guys suggested an insulated door, but I thanked them and said no because I don't care for the garage to warm up in the winter and create a corrosive atmosphere of melting snow and salt. Great job!
Smartphone Control: Many newer garage door openers allow you to connect the device to your home's Wi-Fi network, according to RW Garage Doors. You then can open and close the door through a smartphone app. In fact, many of these apps will give you an alert on the smartphone when the garage door is open for a certain period. Some opener models even can connect to your existing Smart Home system, incorporating all your appliances on one system.

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