SPIRAL STAIRCASES, PLANNING AND DESIGN
With many years’ experience, we are happy to help you with guidance and advice during planning and design. On ordering, each spiral staircase is drawn up specially and the drawing is sent to the customer for approval prior to manufacturing.
We offer perforated sheet metal with a choice of hole patterns as standard.
Our most common patterns:
- ø15, square pattern c/c 40
- 15×15, square pattern c/c 40
- ø20, square pattern c/c 50
- 20×20, square pattern c/c 50
- ø15, triangular pattern c/c 50
- ø20, triangular pattern c/c 60
Other options are available.
As standard handrails are made of stainless steel tube, Ø 42 mm. For wood handrails, the handrail is ø 50 mm as standard.
Since 2003, we have used stainless steel handrails in our spiral staircases.
We see a number of customer benefits in this, such as a more beautiful product with an even higher sense of quality. Combined with our modern production park, the stainless steel handrail also contributes to very fast delivery times.
Many years of experience with a proven method and a good relationship between anode and cathode where the results do not show any rust, make us very confident that the relationship between hot-dip galvanized and stainless does not cause any corrosion.
The rise should be chosen based on the given height between the landings. A suitable radius and the number of steps per revolution then determine the step rise.
The step rise should be between 160 and 220 mm. The lower the rise you choose, the deeper the step needs to be. The normal rise is about 170 to 180 mm.
The formula for the rise is 2 x h + W = 580-640.
Number of steps per revolution
The step template on the right helps you plan the staircase solution and to determine the number of steps per revolution. The table below shows the tread depth along the path line for each radius and suitable riser heights.
You will find the step template at the bottom of this page alt. click here to go directly to our step template.
|Radius steps/revolution||Tread depth along path*||Suitable riser|
The spiral staircase must be fitted with stays every revolution (2.5 to 3 metres in height). This can be done using the square landing fixing. If the stairs have no square landing on each revolution, bracing must be fitted between the step and wall using custom stays.
When the spiral staircase cannot be braced to an adjacent wall, it needs to be stabilised using a vertical stay. These are attached at the bottom against the completed floor or foundation.
Attachment base plate
Use suitable type of screw taking into consideration the material at the attachment point.
A base must be cast to fasten spiral staircases when there is no existing platform. Wind strengths, etc. must be taken into consideration when designing this.
Note that attachment at the first step must also be done.
Generally, the distance to the base plate from the wall must be at least the stair’s radius plus 50 mm.