If you're buying an older house that has a fireplace, you know that getting the chimney inspected for structural flaws is vital to the safety of your house and family. However, the general structure of the chimney isn't the only thing you should be concerned about. You need to be sure that chimney has a cap that's in good condition. These simple devices, with a solid top and mesh sides, do so much to keep your chimney and home safe that if you don't see one on the home's chimney, you can take it as a sign that there may be hidden issues affecting how the chimney works.

Animals and Birds Can't Get In, and That's Crucial

The cap's function, of course, is to keep things out. This includes animals, which can get into the chimney in greater numbers than you realize. Letting birds and animals get into your chimney increases the risk of the chimney becoming clogged, which can send smoke from a fire back down into your home. The animals and their nest materials can also catch fire, and while the brick in a chimney might not burn, it can become brittle and damaged, and if the flames find a way out, they can ignite other portions of your home. Having a chimney cap that is bolted onto the chimney and that is in good condition -- no holes or bent parts -- helps prevent animals and birds from accessing the recesses of the chimney.

Leaves and Twigs Stay out, Too

Another fire risk that caps prevent is that posed by leaves and twigs blown into the chimney. These can fall down to near where the flames usually are when you have a fire going, again increasing the risk that the flames will find more areas to burn.

No Snow, No Rain, Less Muck

A less frightening but just as frustrating issue is rain and snow getting into the chimney and adding to the general muck inside. When it's not raining or snowing, you can get a lot of dirt and dust being blown into the chimney. While the mesh sides of the cap won't really stop that dirt, the solid top will stop the rain and snow from turning that dirt into mud and muck inside the chimney.

If you find there's no cap, get one installed immediately and have the chimney thoroughly cleaned out. Even if there is a cap, ensure the chimney is clean because the previous owners might have installed the cap without properly clearing out the chimney.