Classroom Design Project Training Video: Creating a Stair Landing
Stair landings are platforms between stair sections and can be created in either of two ways.
Up to five stair sections can be connected to one landing. For example, two or three stair sections might meet at a landing with a single stair section continuing to the next level.
To be linked by a landing, all sections must be drawn in the same direction (UP is preferable) and the top of one section should be near the bottom of the next.
A landing formed between two stair sections having less than a 90 degree angle between them are created with a short edge not less than 6" (150 mm). This is because most building codes require the shortest tread to be at least 6" wide. This edge can be manually edited to less than 6" if needed.
Landings can be edited like CAD polylines. You can add or remove edges, convert an edge from straight to curved, or vice versa. A curved landing creates curved railings.
You can also create a stair landing out of closed polyline created with the CAD tools using the Convert Polyline
edit button. See "Convert Polyline".
Landing height can be either user-defined or controlled by the program. A landing with a program-controlled default height is unlocked. The height of an unlocked landing adjusts as the stairs attached to it are modified.
If you specify a height for a landing, that landing is locked. A locked landing maintains that height no matter how you adjust the stairs connected it.
By default, a new stair landing is unlocked, so the stair sections attached to it determine its height. If the entire stair system forms a single path from the lower to the upper floor with each landing connecting only two stair sections, the program can set landing heights without any difficulty.
In this example, two stair sections of the same length are located within a stairwell and connected by a landing. Both stair sections have seven treads. Because the landing height is set automatically according to the number of treads, all treads have the same tread width and riser height.
Since both stair sections are the same length, the landing height is a half of the total height between the two connected floors.
A change to either stair section affects the height of the connected landing and the other stair section. The program tries to maintain the connection to the floor above, and the landing adjusts in height so that the entire stair system has the same riser height, regardless of how many stairs are placed on each side of the landing.
If more than two stair sections meet at a landing, the relationship between them becomes more complex. In this situation, you may want to define the exact height of the landing instead of letting the program define it for you.
Stair sections connected with a landing also move together unless Stair Sections Move Independently is checked in the Preferences dialog. See "Architectural Panel".
A locked landing has a specifically defined height that does not adjust automatically when there are changes in the attached stairs. Instead, the stairs adjust to the landing.
For example, start with the same staircase used to illustrate unlocked landings, with one change: the landing height is now defined at 75 inches (190 mm).
Notice that a tread is subtracted from the top and added to the bottom. The program makes this adjustment to keep the riser heights within a reasonable range.
The stair sections no longer relate to each other when they are attached to a locked landing. Changes to one stair section do not affect the other.
In this example, each set of stairs is adjusted so it bridges the height from the floor to the landing. Since the landing height is above the halfway mark, the upper stair section has very shallow (5") riser height, and the lower section has a steeper (7-1/2") riser height.
When a locked landing is used, the Staircase Specification dialog shows only the selected stair section and those connected to it by unlocked landings, rather than the entire stair system.
When a stair section is moved, all unlocked landings and any stair sections connected to those landings move as well. A locked landing, does not move when attached stairs are moved. To move a stair section independently, select this option in the Preferences dialog. See "Architectural Panel".
You can use a locked landing to break up a complex network of stairs and landings into smaller pieces with known starting and ending heights.
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