Attic stairs glossary:

Attic Stairs by other names: There are many different names and terms used to describe attic stairs. Sometimes they are called attic ladders, disappearing attic stairs, disappearing attic ladders, folding attic stairs, folding attic ladders, and even loft ladders. While all of the names are correct, we have decided to use the term 'attic stairs' for our product.

Vertical opening access ladders, sometimes called loft ladders, are units installed in the wall or other vertical surface, and they utilize telescopic ladders extended from the opening to the floor.

Types and Styles of Attic Stairs: There are actually many different designs of attic stairs; the most common styles are described below. All accomplish the task of folding, retracting or storing the attic ladder in the attic opening or the attic itself.

• Folding Attic Ladders: The most basic and common type of attic ladder, the entire ladder is usually divided into three sections that are folded on top of each other when stored. When in use, the attic stair's door is opened and the ladder is unfolded to the floor. Once the ladder sections are unfolded, they are safely braced against each other and will not collapse under the weight of the user. All folding ladders have to be cut to length by the installer after installation. Calvert Stairs offers wooden and aluminum folding attic stairs for residential use. One exception to the basic three section attic ladder are Calvert Compact Wooden Folding Attic Stairs, a four section ladder. The last two sections can not fold flat on the top of each other and are braced vertically on the top of ladder.

• Telescopic Attic Ladder: It is also known as concertina ladder or accordion ladder. It is a ladder designed from small sections, one section per step section, to form a one long ladder section. The advantage of these strong, and sometimes larger, ladders is that they will usually store within the attic opening and they are relatively easy to operate. Common assumptions are that this ladder extends down to the ground at the angle that it will be used and does not require any additional swing space; they are false. Most of these ladders do require a rather large swing area to unfold. The exceptions are Calvert Aluminum Telescopic Attic Stairs and Calvert Aluminum Attic stairs for existing openings. Calvert Steel telescopic attic stairs require additional swing clearance to extend.

• Sliding Attic Ladders: These are still used today, yet rarely. Usually the one-piece long ladder slides over in the attic for storage, and the entire ladder is pulled down by using system of pulleys. In some cases, these ladders are aluminum and made up of several sections that will slide over each other. Calvert USA does not offer any ladders using this design.

Materials used to construct attic stairs:

• Wood: the most common material, is used in folding and sliding stairs.

• Aluminum: the most versatile material, used in all the designs, cut sections of aluminum are bolted together (Calvert Aluminum Telescopic Attic Stairs use cast metal sections, instead of rolled and formed).

• Steel: rarely used, can be light, strong, and easy to operate with a good design

Attic stairs term glossary:

• Attic Stairs: referring to the entire assembly of attic ladder, the door, frame and hardware as one unit.

• Attic Ladder: referring just to the ladder section a use would use to climb on, part of attic stairs unit.

• Rough Opening Size (RO): this is the opening in the ceiling before the attic stairs are installed; it is measured from the inside of the opening.

• Floor to Ceiling Height ( F to C ): vertical measurement from the finished floor to finished ceiling (assuming the attic stairs will be installed flush with the ceiling).

• Landing Space: measured by locating the hinged end of the attic stairs, transferring that point vertically down to the floor, and measuring forward to the front edge of the attic ladder resting on the floor. In the case of folding ladders, the given landing space measurement is at the maximum F to C distance; when F to C is less than maximum, the ladder is trimmed in length with the angle remaining the same, the landing space will be reduced accordingly.

• Swing Clearance: measured by locating the hinged end of the attic stairs, transferring that point vertically down to the floor, and measuring forward to the front edge of the attic ladder as it is being unfolded or extended. Most attic ladders need more space to unfold or extend then the landing space. The swing clearance will change according the length of telescopic stairs, but it will not change for folding ladders, because it is measure to the end of the 2^nd folding section.

• Weight Capacity: the total weight the ladder will safely support, including the user and what ever the user is carrying (not the weight of the attic ladder). The attic stairs are actually tested using a much higher weight than the published maximum weight capacity, and will most likely not collapse at the weight limit; do not exceed the maximum weight capacity during normal use on a regular basis.