Stair Lift Configurations
There are two basic types of configurations for stair lifts, straight and curved.
Straight Stair Lifts
Straight stair lifts, as the name implies, work on straight staircases and they only work on straight staircases. They won't be able to work on stairways with any type of curve or corner and they won't work if there is an intermediate landing on the stairway.
That said, they will work on the straight sections of stairs with landings and turns. The straight stair lift can be installed from the lower level to the landing and a second stair lift can be installed from the landing to the upper level of the staircase. The disadvantage of doing using two straight stair lifts where there is a landing is the user must transfer from one stair lift to the other on the landing which can be annoying and, in some cases, unsafe.
The big advantage of using two stair lifts to deal with an intermediate landing is it will often be less expensive than purchasing a single curved stair lift that will travel through the landing and negotiate the turn, if there is one.
A second advantage is they are pretty generic and the owner will usually be able to take them with them if they move. Assuming that the new staircase isn't longer than the original one. Straight stair lifts can be cut to fit shorter stairways but new tracks need to be purchased to make them longer. With the newer styles of stair adding new track should be fairly easy. The older models are difficult and expensive to add track sections to because of the close fit between the track and stair lift chair.
Curved Stair Lift Configurations
Stair lifts that will work on curved stairways will also work on straight stairways but are generally custom built to fit and because of this tend to be more expensive than a standard straight stair lift.
Below is a list of common options curved stair lifts can have and a brief explanation of each:
- Top or Bottom Overrun - An overrun can be at either end of the staircase or both ends. It is where the star lift track runs along the floor away from the bottom, or top, of the staircase. It can usually be whatever length the user would like.
- Intermediate Landing - An intermediate landing is where there is a flat area part way along a staircase. Curved stair lifts can follow the slope of the staircase, level out at the landing and then conform to the slope of the next section of the staircase.
- 90° Flat Landing - This is a flat landing that involves a 90° change of direction in the staircase. As with the the intermediate landing, the curved stair lift will follow the slope of the stairs but make a level turn on the landing.
- 180° Flat Landing - The same as the 90° flat landing but the turn will be 180° on the landing.
- 90° Short Spiral - The 90° short spiral is similar to the 90° flat landing but there are usually 3 or 4 pie shaped steps throughout the turn. Again, the stair lift rail will follow the slope of the staircase throughout the length of the staircase including the curve.
- 180° Short Spiral - The same as the 90° short spiral but twice as long involving 6 to 8 pie shaped steps and a 180° turn.
- Large Radius Spiral - A large radius spiral is a staircase that is curved all the way through the stairway with pie shaped steps almost the entire length. The curved stair lift will follow the slope of the large radius spiral throughout its length.
- Outside Curve - An outside curved stair lift follows the slope of the stairs along the relatively gentle outside arc of the staircase. this is the most common form of curved stair lift and can be used on any of the options above that involve a change in direction along the stairway.
- Inside or Reverse Curve - A reverse curve stair lift follows the slope of the stairs on the inside arc of the curve as opposed to the outside arc of the stairway. The curve is much sharper and the slope is much steeper on the inside of the arc but some stair lifts can work.
Because of the custom nature of curved stair lifts they can not normally be used in any location other than the location they are originally designed for. Even if the two stairways look identical, a fraction of an inch difference on the height or depth of the stair treads or a difference in the length or angle of the stairway will prevent its re-installation.