If you're looking for the reason your home always feels too warm or too cool, start at the top -- with the roof. Your roof must do more than merely keep rain and wind out; it must also provide a reliable thermal barrier between outdoor and indoor environments. Here are four things you can do to improve the energy efficiency of your entire home from the top down.

1. Inspect and Repair Damage

A little gap in your roof from damage or disrepair can eventually add up to big energy bills. The most obvious time to schedule a roof inspection is right after a big storm, but practically any roof will wear out sooner or later, even under fair weather. The smartest strategy is to purchase an ongoing inspection and maintenance package from your roofing contractor, like Metal Roof Outlet Inc. These professionals can alert you to problems you might never notice otherwise. Once you've had any necessary repairs made, periodic inspections can help nip future issues in the bud.

2. Add More Attic Insulation

Situated directly underneath your roof, your attic provides a second line of defense against thermal inefficiency, working in partnership with the roof to stabilize temperatures in the rest of your home. Take a look at your attic surfaces, especially the ceiling. Do you see exposed joists or bare wood anywhere? If so, you probably don't have the 12 to 25 inches most attics need, meaning that your roof isn't getting much help in the fight against the great outdoors.

Thankfully, fixing this deficiency is easier than you might think. If you already have insulation in place, you can spray a second layer of insulating foam directly over it. Make sure every nook, cranny, and joint receives enough foam to prevent any air movement. Pay attention to the R-rating listed on the insulation, since the Department of Energy recommends total R-ratings ranging from 30 to 60, depending mostly on how far south or north you live.

3. Switch from Dark Asphalt Shingles to Almost Anything Else

Asphalt shingles are relatively cheap and easy to install, making them a popular choice for homeowners. Unfortunately, they have some serious deficits in the thermal efficiency department, especially if they are black or some other dark color that readily absorbs heat. Thermal expansion can also cause asphalt shingles to split or crack, robbing you of even more insulation.

If you need to replace a worn-out set of shingles, give serious thought to switching from asphalt to some sturdier, more energy-efficient roofing material such as clay, concrete or metal. These products are frequently available in lighter colors that absorb less heat. If you must have shingles, switch to a lighter color than the traditional black or charcoal gray.

4. Install a "Cool Roof" Membrane

If your home's bold modern styling includes a flat or gently sloped roof, you might not need to replace the whole thing -- instead, you can simply cover it with a "cool roof" product. These products are designed to fit over an existing roof, with tight seals around vent pipes and other structures. They are generally bright white or some other very light color to reflect as much sunlight as possible. Popular cool roof membranes include:

• Single-ply membrane - A rubberized coating rolled onto the roof in large sheets and then secured firmly into place 
• Bitumen sheet membrane - A multi-layered, reinforced, asphalt-based material with reflective granules built into it

As you can see, there are plenty of steps you can take to get the top part of your home behaving more efficiently, from beefing up your insulation to brightening your roof's color. Talk to your roofing contractor about which options are likely to make the most sense for your particular situation.