Ladder stairs: a) based on wooden beams, b) on reinforced concrete ceilings; 1 - cheek bar, 2 - degrees, 3 - handrail, 4 - connecting plates, 5 - kotew, 6 - beam ceiling.
In wooden and single-family buildings (up to 2 storeys) wooden stairs are most often used. In recent years, however, stairs are mostly made of refractory materials, and only the steps are clad with wood.
The picture above shows a ladder staircase (trees), which are used in farm buildings and small residential houses. These stairs consist of stringers and steps (footrests). The footrests of the steps are inserted into the furrows of the cheeks to a depth 2-2,5 cm. The connection of the footrests with the cheeks is done with or without a dovetail (Lynx. a).
The stairs are mainly made of pine wood. The footrests of the stairs with higher traffic and in premises with a higher standard of finish are made of oak wood. The wood used for the stairs should be suitably dry. All connections of elements should be carefully and strictly made, that there are no annoying creaks when using the stairs.
Cheek stairs: a) stairs with treatment steps, view and projection, b) detail of the cheek bar rest on the landing bar, c), d) details of the connection of the landing beam with the post; 1 - cheek bar, 2 - landing beam, 3 - post, 4 - footrest, 5 - footrest, 6 - grooves for embedding steps.
The most common are stairs with steps embedded in string beams, less often with the cheeks. The cheeks of the runs may rest their ends on the landing beams (Lynx. b) or they can rest in the sockets made in the posts placed on the landing beams through the tenons (Lynx. d). The fore-rest of the step is inserted into the upper leg rest with a half-groove and fastened with nails or screws to the rear side surface of the bottom leg.. In order to prevent subsequent creaking of the stairs, the upper edge of the riser should be about 3-5 mm higher in the center than at the ends.