A built-in attic ladder makes every trip up and down from the attic easier, faster and safer. It can make the difference between a storage space that actually gets used and one that is quickly forgotten — along with its contents. Installing an attic ladder or fold-down stairs is a very doable DIY project that can take just a few hours. Most ladders and stairs come as pre-assembled kits that you can order for shipment to your house or pick up at a local building supply store.
Consider the following factors before you buy.
Location, Location, Location
Attic ladder kits are made to fit between existing framing in the ceiling (that is, the floor of the attic). And they may require that an existing attic access hole be enlarged just a little. If you are lucky, you will be able to take full advantage of that convenience. Often, however, you won’t be so lucky. In this case, you should plan on cutting and framing a new access opening. Also, make sure the bottom of your ladder will rest in a safe spot with room to maneuver.
Type of Framing
Your attic floor and roof are probably framed with either trusses or individual rafters and floor joists. Truss roofs function as an interlocking system and the components should not be cut, while standard framing can usually be reorganized easily. If you have trusses and discover that they are in the way of your planned attic ladder location, seek professional advice before proceeding.
Joist (or Truss) Spacing & Orientation
Standard-size attic ladder kits are designed to fit between floor joists (or trusses) with 24" spacing. This means there is about 22 1/2" of open space between each joist pair. If the gap between your framing measures 22 1/2", and one of those gaps falls over where you’d like to install the ladder, you’re in luck.
If not, additional framing will be required.
It's also possible that the joists are running in the wrong direction for your ladder installation. With standard framing, this can be overcome by simply cutting the joists and then surrounding the rough opening with doubled-up headers and joists. With trusses, however, you may be out of luck. Check with a professional about your options.
Basic Space Requirements for an Attic Ladder
Full-size attic ladders and stairs usually need an opening in the ceiling that is at least 22 1/2 x 54". This is the first thing to check. Also make sure there is a suitable landing space in the attic, so you can safely mount and dismount the ladder (usually while carrying storage items). Check for headroom, too. You don’t want to be banging your head against the roof framing every time you use the ladder. Finally, make sure there's enough open space in the room and on the floor below the attic opening to accommodate the ladder when it is fully extended. These dimensions vary by ladder type and model, so check the manufacturer's requirements for the exact model(s) you're considering.
If space is tight, look for compact ladder models designed for closets and other small spaces. Some models need only an 18 x 24" opening and less floor space than standard ladders.
Length & Weight
Attic ladders are sold in different lengths. Be sure to measure the distance from your ceiling to the floor and buy an appropriate size. Weight relates to the load capacity of the ladder itself. As a general rule, the more weight a ladder can hold, the sturdier it is. At the very least, buy a ladder that can handle the weight of the heaviest person who will be using it plus the heaviest load they will be hauling up and down. That may mean that a 250-pound capacity is suitable, but I feel more comfortable with a minimum of a 300-pound capacity, even if that means I have to do some additional framing.
You can find attic ladders made of aluminum, steel, and wood. Aluminum is generally the best all-around choice because it is lightweight and strong. Plus, it's a rust-resistant metal, so it's unlikely to be affected by humidity and temperature over the years. A wood ladder might very well last as long as the house, but being a natural material it is theoretically more prone to the effects of moisture and temperature change as well as potential natural defects.
Attic ladders and stairs come in variety of styles and designs that incorporate various features that aid convenience, safety, and general usability. Much of this comes down to personal preference. Here are some of the features to consider, keeping in mind that you may be limited by your available space (not to mention budget):
- Folding vs. telescoping: Some ladders fold out, while others telescope like an extension ladder. There are also stairs that extend on scissor-like mechanisms (picture an old-fashioned shaving mirror), sometimes called "concertina."
- Angle: Attic ladders and stair are almost always steeper than regular staircases, but you may prefer less or more angle. Ladders typically have the same angle you'd use when painting your house or cleaning windows. Stairs usually have an angle that's less steep.
- Handrail: Both ladders and stairs can include a handrail. Keep in mind that climbing attic ladders usually means you're carrying storage items in one hand while climbing with the other. Would you prefer to climb with a handrail or just use the ladder rungs?
- Rungs vs. steps: Attic stairs have shallow steps, while ladders may have steps or, more commonly, ladder-style rungs. The steps aren't like those of a regular staircase, and, in most cases, you should climb up and down as though you're on a ladder.
Attic access panels and ladders or stairs can be significant sources of heated and cooled air loss in a home. Look for models with tight-fitting doors and, if possible, insulation. Otherwise, you can add weatherstripping around the door opening to stop air leakage, and cover the door panel with rigid foam insulation board to slow heat loss.