Do your home components need updating?

Often the first sign that your kids are sick is that they aren't as playful as usual, or they might suddenly say, "I'm not feeling good," and without leaving you enough time to say, "'Well' -- you're not feeling 'well,'" they upchuck on your feet.

The health of your home components can be even harder to predict. Unless you're paying close attention, you may not realize anything is wrong until your house springs a leak, something falls off of it or you turn on your heat or A/C and…nothing happens. You need to be vigilant to any signs something is amiss or the damage from one system failing can be compounded by affecting something else. If your house has no heat in the dead of winter, for example, your pipes could freeze, and then you'll have to call not only an HVAC technician but a plumber, too.

Regular home maintenance can keep major repairs and replacement of home components at bay just so long, however. Just like death and taxes, you can't prevent the inevitable, and the day will come for each major system and component in your home to be replaced. How do you know when it's time? The life span of home components varies, but most of the major ones usually last at least 10 years -- some, considerably more.

Roofing

The problem with roofing is that unless you're a roofer or circus performer, climbing up and inspecting your roof might not be a skill set of yours. Even if you don't do any damage to yourself, you can damage your roof by walking on it. Even many home inspectors make only a visual inspection of your roof from the ground using binoculars or the top of a ladder so they won't do any damage. They also check the attic for signs of leaks. You should do the same each year, looking for obvious signs of wear and tear, including the following:

• missing shingles
• broken or deformed shingles
• shingle granules in the gutters
• signs of leaks in the attic

If you've got to break out the buckets whenever it rains or you've seen mysterious stains on the ceiling, call a roofing professional at once to inspect your roof for leaks and evaluate the entire roof -- including around flashing, vents, skylights and chimneys, soffits, fascia, and gutters. Depending on the age and condition of your roof, it may be too late for repairs. Life expectancy of roofing materials varies. Slate roofs, concrete, and clay tiles can last 100 years or more; three-tab asphalt shingles, the most popular roofing in the U.S., only about 20 years.

HVAC

Central heat and air conditioning are two things you might miss if they are not working, and you usually only notice they are not working when you need them most. At other times, one or the other or both are dormant.

Regular maintenance and changing the filters can keep them both running optimally, but because they involve so many moving parts, sooner or later they conk out -- according to the International Association of Certified Home Inspectors, furnaces have a life span of about 15-25 years, while central A/C usually lasts a maximum of 15 years. When either your furnace or your A/C reaches its prime, keep a close watch on them for these signs of failure:

• furnace that produces uneven heating
• extremely dry conditions when heat is running
• burning or other unusual smell when A/C is on
• frequent maintenance
• increasingly high utility bills

If it's time to replace the A/C, EnergyStar.gov recommends replacing the furnace, too, if it's 15 years old or more. The reason is that they usually share a blower, and if the furnace is old, the newer, energy-efficient A/C may not work optimally with the old furnace's blower.

Siding

There are not many types of siding that need frequent replacing. Most can last 100 years or more, but if you have an older home, or your house is clad in wood or aluminum siding, you may be in the market for some new siding. Obviously, if your wood siding has been neglected because it's high maintenance, it could be rotting or infested with termites and other wood-munching insects. Aluminum's main problem has always been dings and dents.

As for vinyl, it's typically good for a lifetime, in some cases lasting almost as long as stucco, brick veneer, and stone, but you could run into one unusual problem from neighboring homes with low-e, double-pane windows. In some parts of the country, homeowners are noticing that these newer, energy-efficient replacement windows reflect the sun with such intensity, especially in the winter, that they melt the neighbors' vinyl siding. If you're the neighbor and planning to replace your old aluminum or wood siding with vinyl, look for a heat-resistant grade.

Your home may not say it's not feeling well, but if you watch it for the signs, you can upgrade before it does you dirty.