Sizing and Choosing Pulldown Attic Stairs
Follow these guidelines when inspecting an existing folding attic stair unit or replacing one for a customer
A few years 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 TOH general contractor. "You wouldn't use a broken ladder, and you definitely shouldn't use a broken attic stair."
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. If you come across an old attic stair on a job, 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 (image 2, left). 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 22½ 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 for a customer who carries large loads in and out of the attic.
Gaps at hinges
A sure sign that something is sagging, putting excessive strain on the hinges. Check and tighten all bolts on the stringers, and make sure the jamb is stoutly anchored, as described below. A gap like this could also result from a bottom section that has not been properly trimmed to fit.
Getting the Right Fit
You'll need at least three critical measurements: the width and length of the rough opening, and the ceiling height (image 3, left). 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. Drop a plumb bob from the header and measure out from it to find this distance.
Click through photos 4 through 7, at left, for a simple guide. Look for a stair with a load rating of at least 300 pounds, which have the sturdiest treads, stringers, and hinges.
Where to Find It
Wood folding stair:
Airtight Attic Access Ladder
Resources Conservation Technologies
Metal folding stair:
Bessler Stair Company
American Stairways Inc.
Calvert USA Inc.