How often should you inspect your attic?

Short answer

Inspect the attic twice a year, in spring and fall, and go up after any heavy storm to look for leaks. The attic is where a house's worst problems show first: roof leaks, which stain the underside of the deck long before they reach a ceiling, and rodents, which move in when the weather turns and chew what they find. A look with a flashlight takes 20 to 30 minutes and costs nothing.

Why it matters

Nobody goes into the attic, which is why things go wrong there quietly. A roof leak soaks the insulation and the deck for months before a stain appears on a ceiling, and by then the wood is rotting and the insulation has lost its value. Mice and squirrels find the attic through a gap at the eaves or a loose vent, nest in the insulation, and chew. What they chew is often wiring, and chewed wiring in a space full of dry wood and paper-faced insulation is how attic fires start.

The attic also tells you about the rest of the house. Mold on the underside of the deck means the attic isn't venting and moisture from the house is condensing up there. Insulation that's been pushed aside or flattened means heat is pouring out of the rooms below. A short look with a flashlight twice a year catches the leak while it's a shingle, the mouse while it's one mouse, and the problems that would otherwise cost a roof repair of $8,000 to $25,000 or an electrician's emergency call.

When to do it more often

The index gives one modifier: a heavy storm. Go up afterward and look for new wet spots, drips and daylight, because a lifted shingle or a damaged vent shows there first. Beyond that, go up when you hear anything, scratching or scurrying at night means something has moved in, and when the roof is older than its 20 to 30 year life, which makes leaks more likely every season.

What you need

A flashlight, a bright one, since attics have little or no lighting
A dust mask, for the insulation fibers and whatever the rodents left

Steps at a glance

Go up in daylight, with the attic light off at first, and look for pinpoints of daylight through the roof, which are holes.
Switch the flashlight on and sweep the underside of the roof deck for dark stains, damp patches and mold.
Look along the floor and the insulation for droppings, nests, tunnels and shredded material.
Follow any wiring you can see and look for chewed insulation on it.
Check the insulation for wet spots and for areas that have been flattened or pushed aside.
Look at the vents, the eaves and the chimney for gaps an animal could use, and at the attic hatch for a seal.

You're done when you've seen the whole deck and floor and found no daylight, no damp, and no sign of anything living there.

Signs it's overdue

Droppings, which look like dark grains of rice, on the insulation or near the hatch.
Chewed insulation on wiring.
Nests of shredded paper, insulation or fabric.
Disturbed insulation, with tunnels or flattened paths.
Daylight through the roof.
Water stains on the deck or the rafters.
Mold, usually dark patches on the underside of the deck.

DIY or pro

The inspection is an easy job, if a hot and dusty one in summer. Stay on the joists or the boards laid across them, since the drywall between the joists won't hold a person. What you find decides the rest. A single mouse and a gap at the eaves are a trap and a tube of caulk. A squirrel family, raccoon droppings, or signs that rodents have been there for a long time are a job for a pest company, which charges $150 to $400 to remove them and seal the entry points, and the sealing is the part that matters.

Chewed wiring is an electrician's job, and a stained or soft patch of deck is a roofer's. Don't put either off, since the attic is where both problems grow fastest.

Safety

Electricity: wiring in an attic is often exposed and may be chewed. Don't touch bare or damaged wires, and if you find any, switch off the circuit if you can identify it and call an electrician.
Structural: walk only on the joists or on boards laid across them. The ceiling drywall between the joists won't take your weight, and a foot through it is the mild outcome.

FAQ

How do I know if I have rodents in my attic?

Droppings, nests of shredded material, tunnels in the insulation, and chewed wiring or wood. Scratching sounds at night are the other giveaway.

How often should you check the attic for leaks?

Twice a year, and after any heavy storm. A leak shows on the underside of the roof deck long before it stains a ceiling.

What should I look for in an attic inspection?

Daylight through the roof, water stains, mold, droppings, nests, chewed wiring, and insulation that's wet, flattened or pushed aside.

Is it safe to go into the attic?

Yes, with a flashlight, a dust mask, and your feet on the joists. The ceiling between the joists won't hold you.