Stairs That Disappear

About a year ago, Tom Silva was halfway up a folding attic stair, trying to figure out why it wasn’t working right, when a loose screw let go, a spring popped, and the stair swung out from under him. Tom crashed to the floor and broke his foot, an injury that forced him to spend the next six months on crutches. The lesson? “An attic stair is a ladder,” says the This Old House general contractor. “You wouldn’t use a broken ladder, and you definitely shouldn’t use a broken attic stair. Replace or repair it immediately.”

Tom’s experience may be extreme, but lots of people take their attic stairs for granted, or put up with stairs that don’t operate smoothly or have loose or broken parts. Every time you pull down the stair, check that the hinge nuts and bolts are tight, the springs are anchored securely, the pivot arms are straight, and the treads and stringers are intact. And when you step on it, it should feel solid. “An attic stair shouldn’t move at all under your weight,” Tom says.

You can get replacement parts from most manufacturers, but if the repairs are numerous or frequent, it’s time for a new stair. There are plenty of choices that will fit into an existing opening — typically 22 1/2 or 25 inches by 54 inches. Some slide, some fold; a few have rails that telescope like an old-fashioned shaving mirror. You have your pick of wood, aluminum, or steel in different heights, weights, and load capacities. You can find stairs that ascend at a shallow angle, stairs that take up minimal landing space, or stairs that seal tightly to the ceiling so heat stays in the house.

While you’re at it, take note of tread width. A wider stair is a big plus when you’re stowing a box of Christmas ornaments. And whether you install it yourself or hire a pro, follow Tom’s hard-won advice: “Make sure it’s tight, true, and strong before setting foot on it.”

Getting the Right Fit

Before replacing an attic stairway, you need at least three critical measurements: the width and length of the rough opening, and the ceiling height. Measure the rough opening’s width and length in three different spots, at the top and bottom of the framing. Choose a stair that fits into the smallest of these measurements and is long enough for your ceiling height; you may have to trim to fit. For a folding or sliding stair in a closet or other tight space, you also need to measure how much swing clearance and landing length the stair will need when lowered. (Make sure to check manufacturer’s specs before purchasing.) To make this task easier, hang a weighted string from the header where the stair’s hinge will be attached, and measure out from the string. Replacing an existing stair is a two-person project that can take a morning or a weekend, depending on your skill. But if lifting 75 pounds overhead isn’t your strong suit, hire a contractor to do it for you.

Buying Stairs

See the photos to the left for a simple guide. No matter which stair you choose, make sure it has a load rating of at least 300 pounds, which ensures that treads, stringers, and hinges will be more robust than on lighter-duty models.

Troubleshooting Common Problems

Stair-door trim pulling away from the ceiling

This is an unmistakable sign that the stair’s jamb is loose and pressing down on the trim around the access door. To fix it, push the jamb up flush with the ceiling and hold it in place with shims slipped between the jamb and the framing, particularly at the hinge end and on the sides directly beneath the pivot arms. Fasten the jamb through the shims using 16d common nails, wood screws, or lag screws. Drywall screws or box nails aren’t strong enough.