“The roof caving in” and “keeping a roof over your head” aren’t idioms for nothing; it’s because roofs are one of the most—if not the most—essential parts of your home. Aside from the obvious perils of a roof collapse, a compromised roof can cause all sorts of other issues for the rest of your house. So maintaining the integrity of your roof is one of the most important investments you can make in your home.

In Boulder, a new roof costs an average of about $8,400 to install—although there are a lot of variables such as the size of your roof and the materials used. Depending on the severity of your roof issues, you might not need a full installation; you could get away with a repair—and a smaller bill (about $740). But if you need a new roof, it’s better to invest in it now before it becomes a more serious issue—or even comes caving in around you. More than 3,000 roofs collapse in the U.S. every year.

And once that happens, you have to worry about dealing with insurance adjusters. And no one wants that.

So before anything like that happens, keep an eye on your roof and get it replaced sooner rather than later if you need to. Here are some of the big signs to look for:

Light in the attic: Without having to get up on the roof, you can tell you might have a problem if you go into the attic and see light coming through. It’s a sign of weakening spots in your roof, and indicates moisture may also be sneaking in. And speaking of which…

Water damage: If you’ve got a leak in your roof, you’ve got an obvious problem. But water damage takes many forms. Moisture is a nefarious foe when it comes to your roof. It sneaks in easily and can quickly compromise your roof if you don’t catch it soon enough. In addition to leaks, look for:

  • Water stains in the ceiling
  • Peeling or blistering paint
  • Mold or mildew growth on your roof shingles or your walls
  • Swelling in your woodwork
  • Roof sagging

These aren’t all guaranteed signs of a leaky roof, but they’re worth having checked out just to be safe.

Hail: If you’ve recently dealt with a hailstorm in your area, it’s probably time to have your roof looked at. Colorado is one of the most hail-prone states in the country. Between 2013 and 2015, the state had the second highest number of claims as a result of hail damage. And the Front Range is smack-dab in the middle of “Hail Alley.” The Colorado Roofing Association warns that after severe hail, damage to your roof could rapidly accelerate, so it’s important to have damaged assessed.

Shingle issues: If you have any missing, torn or buckling shingles, you might have a problem. If the damage is isolated to a single area, you might only need a repair. But you should address the problem now before it becomes a bigger one. Also, when you’re cleaning your gutter, keep an eye out for excessive shingle granules (they look like big pieces of sand). If they’re shedding off your shingles in a large quantity, it could indicate your roof is at the end of its lifespan. Which brings us to…

Your roof’s age: Depending on what your roof is made of and other wear and tear, you may need to start thinking about replacing it if it’s getting up to the 20-25 year mark (although some roofing materials lasts longer). If you’re crossing that threshold, get an inspector out to evaluate the state of your roof. After all, nothing lasts forever, and that includes your roof.