Patent Grant
12258764
This invention is in the field of staircases and staircase construction kits.
Staircases (stairs) generally comprise various elements. These include steps or treads typically placed on stringers, providing the treads' load-bearing support. The stringers give the basic zig-zag shape to the staircase. Risers, generally positioned between each step, as the name implies, help provide the elevation change between each step. Risers are typically positioned perpendicular to each step and are usually held in position by the stringer. Staircases usually have handrails or banisters to help the stair users keep their balance. These banisters are often attached to Newel posts at opposite ends of the stairway. The banisters often have balusters or spindles to help prevent falls from the staircase. The top of the stairs is often called the upper landing, and the bottom is often called the lower landing.
Stairs are a common building component and as a result, are the subject of numerous safety codes and building codes. For example, in California, building codes for homes require that stairs should be at least 36 inches wide, the risers should be between about 4 and 7-8 inches high, and the risers should be of consistent height within about ⅜ inches. The treads and risers should be level with a maximum slope of about two degrees. Staircases should also have handrails on each side and level landings.
Prior art stairs that comply with relevant building codes are generally fixed structures that are usually custom-built to fit the requirements of that particular building. In particular, the stairs must precisely accommodate the differences in height (story height) between the bottom of a lower floor and the bottom of the floor above. For residential buildings, this average story height often differs between about nine to about 10 feet, but this can vary greatly between houses, with some designs going up to 11-12 feet. Commercial buildings often have story heights of 14 feet or more. Thus “one size fits all” staircase designs generally tend to be infeasible. Instead, skilled labor, custom-cut materials (e.g., custom-cut stringers), and custom installation is usually needed.
Attic Stairs: variable height attic stairs are known in the art. These include various folding attic stairs, which can transition between a folded form stored in the attic and an unfolded form that can be pulled down to the floor below for attic access. Such attic stairs generally employ foldable or telescoping riser elements that are not of a fixed (constant) length (e.g., total length), but rather have a changeable length that can usually transition between a first shorter length to a second and longer length.
Due to their limited and temporary use, such attic stair designs are generally exempt from standard staircase codes. Instead, they can follow a different set of regulations that tend to be more permissive. Attic stairs are exemplified by Bessler, U.S. Pat. No. 1,811,709; Triller, U.S. Pat. No. 2,580,978; Allred, U.S. Pat. No. 7,578,371; Winter, U.S. Pat. No. 8,695,576; and others.
The invention was inspired, in part, by the insight that there is an unmet need for a staircase kit that would enable homeowners to install staircases into their pre-existing homes. Such homeowners are typically sophisticated “do it yourself” individuals who, although lacking professional carpenter or licensed contractor certification, often tackle medium-complexity home renovation projects. Such individuals are usually exempt from licensure requirements, but the finished product must still meet the required building codes.
More specifically, the invention was inspired, in part, by the insight that an ideal staircase kit should be able to adjust to a normal variation in one-story floor heights between most homes. Further, an ideal kit would contain all or nearly all of the required staircase components in a precut or pre-formed stage so that further modification is not needed. Instead, the homeowner should be able to take the precut (and fixed length) stringers, steps, risers, banisters/handrails/railings, and the like and assemble them into a code-compliant staircase. At the same time, this staircase needs to be adjustable to accommodate 1-2 foot differences in story height between buildings and still provide level steps and landings.
As will be discussed, in some embodiments, the invention can comprise a kit for producing a staircase device, the staircase itself, or a method of making a staircase. This staircase will generally comprise staircase components such as various steps, adjustable height risers, fixed-length banisters, fixed-length stringers, and Newel posts. The staircase will also comprise a lower landing and an upper landing. Unlike standard designs, the invention's adjustable height risers typically comprise a top riser portion connected to a bottom riser portion by at least one riser hinge. This adjustable height riser enables the riser height to be adjusted by changing the angle (here called the two-portion angle) between the top and bottom riser portions.
For this to work with precut (or pre-formed) stringers, the angle of the staircase itself has to be adjustable. When the story height is longer, the staircase angle (
In some embodiments, the invention may be an adjustable-height staircase or a method of assembling such a staircase. Although configured to be adjustable, this staircase is generally configured to conform to standard US building codes. Among other things, the staircase risers will generally be no shorter than 4 inches high and no taller than 7½ inches high (versions intended for other areas, such as Canada, may have taller risers, such as 8¼ inches high. To avoid creating a tripping hazard and to comply with various building codes, it is generally preferable (or required) to configure all the risers to the same height.
The staircase steps or run will generally be at least 10 inches long. Further, when assembled, the steps will be level with respect to the underlying floor (or, preferably, gravity).
More specifically, the invention may be a staircase device or a method of assembling a staircase device, generally as shown in
Thus, in some embodiments, the invention may be a staircase or a method of assembling a staircase. This staircase will generally comprise various staircase components, such as a plurality of steps (110), a plurality of adjustable height risers (or riser components that can be configured to make adjustable height risers 120), fixed-length banisters (130), fixed-length stringers (150), Newel posts (
Here, as shown in more detail in
According to the invention, the height between the upper landing (170, presumably level with a higher floor level) and the lower landing (160, presumably adjusted to the level of the floor below) can be adjusted, at least in part, by modifying this two-portion angle (212) over at least some (and often all) of these various adjustable height risers. As can be seen, when the riser hinges (210) are folded back on each other, the height of the total riser is about equal to only the height of the top riser portion (122). By contrast, when the riser hinge is unfolded and is essentially straight (as shown in
In a preferred embodiment, as shown in
Note that a series of operations typically adjust the height of the staircase. In addition to adjusting the height of the risers (120), the height of the adjustable height post system (190, 196), the angle of the steps (110) (e.g., the step leveling process), and the angles of various other components are also adjusted.
The height of the adjustable height post system (190, 196) that supports the upper landing frame (180) and the upper landing (170) can be adjusted by various mechanisms. In the embodiment as shown, the adjustable height post system comprises an adjustable support post base (190), and an adjustable support column (196). In this example, the post base (190) and the support column configured (196) are configured to nest partially within each other. See also
Thus, as previously discussed,
Note that if the height of the risers (120) is adjusted, then to maintain the steps (120) at a level orientation with respect to gravity, then the angle of the various steps (110) with respect to the stringers (140) must also be adjusted. Otherwise, the steps would be at an angle, creating a tripping hazard and violating various building codes. Thus, a mechanical arrangement is needed to adjust the angle between the steps and the stringers.
As shown in
In some embodiments, at least some of the steps (110) in the plurality of steps are further attached to the fixed length stringers (140) by at least one turnbuckle adjusted apparatus (such as 200, 224, 222, 226). This apparatus comprises a turnbuckle (226) with a variable turnbuckle length. With this apparatus, the process of adjusting the height between the lower landing and the upper landing further comprises modifying the variable turnbuckle length. This turnbuckle can then adjust the various step-stringer angle(s) so that all the steps are level.
As shown in
Put alternatively,
To accommodate this change in riser length (120), the entire staircase, in turn, has to both adjust its overall height (by way of adjusting the overlap between the adjustable support base (190) and the adjustable support column (196). Additionally, the angle between the various steps (110) and the stringer (140) also has to be adjusted so that the resulting steps always are level with respect to the ground, regardless of the height of the risers (120). Further, the angle of the banister upper and lower railings (130), (132), and even the stringers (132) also must be adjusted. To do this, these components are mounted on various types of pivot joints. Indeed, as will be discussed, even the joints or attachment hardware between the banister (130) and the Newel posts (198, 199) is configured to allow this movement to occur.
To do this, the risers (122) are connected to adjustable runners (220) by runner pivot bolts (222), stringer pivot bolts (224), and turnbuckles (226). As needed, applying torque to the turnbuckle (226) causes the length of the turnbuckle to expand or contract. This, in turn, is communicated to the underside of the step (110) by the adjustable runner (200), which in turn pivots around the stringer pivot bolt (224) attached to the back side of the stringer (140). After adjustment, the desired orientation can be further stabilized with an optional “L” corner brace (228).
The Lower Landing:
As shown in
To allow the stringers (140) to pivot somewhat, each stringer can be attached to either the lower landing (160), or the lower landing frame (162) by a lower landing pivot mechanism such as a pivot bolt or joint (230). Thus, variations in staircase height, caused at least in part by alterations in riser height (120), end allowing a stringer-lower-landing angle (
Put alternatively,
The Banisters:
As shown in
Note that it is often desirable to ensure that the spindles (150) are always parallel with respect to the direction of gravity, regardless of how the banister tilts to accommodate differences in stairway height.
To do this, in some embodiments, the spindles (150) can be mounted between the banister upper railing (130) and the banister lower railing (132) using movable or pivoting joints (250). This enables the spindle angles (151) between the banister upper railing) and the banister lower railing (132) to vary depending on the height of the adjustable risers (120) as well as the height of the staircase and/or angle 197 between the fixed length banisters (132) and the Newel posts.
Put alternatively,
Additionally, note that the angle (151) between the spindles (150) and the upper and lower banister railings (130, 132) will also change somewhat as the riser height (and, therefore the angle of the stringers 140) changes. To do this, in some embodiments, the spindles will be attached to the upper and lower banister railings with spindle pivot joints or other mechanisms (250).
Attachment Between the Banisters and the Newel Posts
Kit Versions
As previously discussed, it is envisioned that home renovation enthusiasts will particularly value the adjustable staircase device and method taught herein. Such individuals often referred to as prosumers, may be amateurs (i.e., not professional carpenters) looking to add one or more additional stairs to their houses. Such individuals often prefer to purchase pre-fabricated kits where the various parts are already precut or otherwise in their final dimensions and may also be packaged with the various types of hardware disclosed herein.
Here, one of the main advantages of the present invention is that the same staircase device may be configured to fit into various buildings with various ceiling heights and floor dimensions. This enables the kit user to adjust the kit accordingly. Indeed, in some embodiments, the kit may be equipped with various precut upper or lower risers (122, 124) so that the appropriate set of riser tops and bottoms of suitable heights may be selected to further customize the staircase according to the particular building.
In such embodiment, the device or method may further comprise precutting or otherwise pre-forming the staircase components and dispensing them as a kit. Additionally, or alternatively, the device and method may further include retrieving these precut staircase components from a previously dispensed kit.
Materials:
Staircases are often made from wood (natural wood) or wood-based materials (e.g., processed wood such as plywood, particle board, and the like. Although it is anticipated that in many embodiments, the staircase taught herein will also comprise wood or wood-based materials, other materials may also be used. These include metal, fiberglass, plastic, plexiglass, glass, ceramic, and other construction materials.
| Number | Name | Date | Kind |
|---|---|---|---|
| 1811709 | Bessler | Jun 1931 | A |
| 2580978 | Triller | Jan 1952 | A |
| 7096998 | Edmunds | Aug 2006 | B1 |
| 7578371 | Allred | Aug 2009 | B2 |
| 8695760 | Winter | Apr 2014 | B2 |
| 10487579 | Rodriguez | Nov 2019 | B2 |
| Number | Date | Country | |
|---|---|---|---|
| 20240287811 A1 | Aug 2024 | US |
