<\/p>\n
![\"spiral](\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2020\/09\/spiral-staircase.jpg\")
Spiral staircase: render produced with Edificius<\/a><\/p><\/div>\n The need to optimize spaces is one of the most recurrent requests that technical experts must address in order to deliver creative and at the same time functional solutions. In fact, when designing a staircase, it is crucial to combine aesthetic, functional and structural needs, such as defining the stairs type, shape, material, structure, location and correct layout. They are choices that obviously affect the final quality of a project.<\/p>\n A spiral staircase design guide can help you to better address all these aspects.<\/p>\n For more information on interior stairs planning, see our Focus insight on \u201cHow to design a staircase: criteria and examples to download<\/a><\/strong>\u201d.<\/p>\n The spiral staircase is a particular type of curved ramp staircase<\/strong> more common in private and residential buildings, in small spaces or in special contexts.<\/p>\n Depending on architectural choices and the configuration of the space in which it must fit, the spiral staircase can have a plan:<\/p>\n <\/p>\n Circular plan | Square plan | Helical plan – spiral staircase produced with Edificius<\/p><\/div>\n The circular spiral staircase is the most common type, as it occupies a smaller area than the other types.<\/p>\n Generally, the structure of the spiral staircases consists of a central support post<\/strong> that develops vertically where cantilevered steps are inserted (as in a cantilevered staircase<\/a>).<\/p>\n You can use a wide variety of materials when building a spiral staircase, however they are usually built in metal or wood or rarely in reinforced concrete in case of outdoor staircases. Steps can be made with any material.<\/p>\n <\/p>\n Spiral staircase design \u2013 floor plan produced with Edificius<\/a><\/p><\/div>\n Opting for a spiral staircase rather than a traditional type of staircase (e.g. L-shaped configured with a rectangular plan, etc.) has obvious advantages<\/strong>, especially in terms of space management. A spiral staircase, in fact, occupies a small surface in plan and can also be positioned in stairwells with a diameter of about 1.20 m.<\/p>\n In addition, a wide range of prefabricated solutions are available on the market that also allow significant savings in terms of cost and installation time.<\/p>\n The square spiral staircase<\/strong> features a helical development on a square or rectangular plan. In this case, the design of the staircase follows a more geometric trend, with trajectories that approach more closely to straight segments.<\/p>\n Compared to the circular version, it can offer steps with a wider tread in the linear portions, improving the comfort of ascent and descent. The square shape adapts particularly well to buildings with angular floor plans or rational internal layouts, where the geometric rigor of the project requires consistency even in vertical elements.<\/p>\n Aesthetically, it presents itself as a more technical and rigorous solution, often used in modern contexts, offices, showrooms, or public buildings. However, its construction can be more complex and requires careful planning to ensure an adequate balance between functionality and stability.<\/p>\n The elliptical spiral staircase<\/strong> represents the most sophisticated and expressive variant. Its development is based on an oval plan, which gives the staircase a fluid yet more dynamic appearance compared to the traditional circular shape.<\/p>\n Thanks to the greater length of the ellipse, this staircase can offer wider and more comfortable steps along the entire path, improving the ergonomics of movement. It is a preferred choice in representative environments, prestigious villas, luxury hotels, or contexts where the staircase is not just a functional element, but becomes the protagonist of the space, almost an architectural sculpture.<\/p>\n However, it should be considered that the elliptical staircase occupies more surface area than the circular one, requires custom design, and generally has higher costs, both due to the construction complexity and the quality of the materials used.<\/p>\n In addition to the shape of the plan, another determining aspect in the design and choice of a spiral staircase is the material with which it is made. The material affects not only the aesthetics but also the stability, the weight of the structure, maintenance, and the final cost.<\/p>\n The most common solutions use:<\/p>\n Metal spiral staircases<\/strong> are among the most widespread due to their versatility, the lightness of the structure, and the ease of prefabrication. Made of painted steel, stainless steel, or galvanized iron, they are particularly suited to modern, industrial, or minimalist contexts. They offer great durability over time and can be designed with very thin profiles, ideal for reducing visual bulk. Additionally, metal allows for lightweight and dynamic self-supporting solutions, often combined with glass railings or wooden steps, for a highly sought-after material contrast. They are perfect for indoor environments but, if properly treated, are also widely used in outdoor spaces.<\/p>\n Wooden spiral staircases<\/strong> are the ideal choice for those who desire a warm, welcoming, and natural environment. Wood, a noble and renewable material, is suitable for both classic and contemporary contexts, depending on the essence used and the finish. Versions in oak, beech, or ash, for example, guarantee robustness and durability, as well as a great variety of colors and textures. The processing of wood also allows for fine shaping of the steps and handrails, making the staircase a piece of furniture in itself. However, compared to metal or concrete, it requires more maintenance, especially in humid environments or those subject to intense wear.<\/p>\n Reinforced concrete spiral staircases<\/strong> represent the most massive and solid solution. They are generally built in situ or prefabricated in elements to be assembled on site. This type is suitable for public buildings, commercial spaces, or large residences where the staircase is integrated into the structure of the building. Reinforced concrete ensures remarkable durability and stability, as well as excellent fire resistance and sound insulation. Aesthetically, it can be left exposed for a brutalist style or finished with plaster, marble cladding, resin, or other materials. Being a heavy and permanent structure, it requires precise planning from the earliest design phases.<\/p>\n To determine the\u00a0correct\u00a0dimensions of a\u00a0comfortable\u00a0and efficient staircase, it is necessary to correctly evaluate the relationship between riser and tread<\/strong>.<\/p>\n Over the centuries, architectural and ergonomic studies have produced various empirical formulas to suggest an ideal rise \/ tread relationship and ensure safe use of the staircase<\/strong>.<\/p>\n The most commonly used formula to calculate stairs dimensions is attributed to the architect Fran\u00e7ois Blondel<\/strong><\/em><\/a>, dating back to 1675. The famous formula is based on the fact that the effort made to lift the foot vertically is equal to twice the effort taken to move it horizontally.<\/p>\n He specified that twice the riser height plus the tread depth equals the step length:<\/p>\n 2r + t = 62\u00f764 cm (25.5 in today’s inches) where r<\/strong> is the value of the riser and t<\/strong> of the tread.<\/p>\n Graphic application of the Blondel formula<\/p><\/div>\n Once the correct relationship between riser and tread has been calculated and they are well proportioned to fit our stride, we need to determine each single value.<\/p>\n For each type of staircase, the tread must not be less than 25 cm<\/strong>. In spiral staircases the triangular shape of the step implies a variable tread from the center of the staircase to the handrail.<\/p>\n Design of a spiral staircase – Section produced with Edificius<\/a><\/p><\/div>\n The actual tread dimensions for a set of stairs should be calculated considering the path of travel<\/strong> that connects different vertical levels by dividing the height between the levels into manageable steps, after having identified the stairs diameter and 30 cm distance from the handrail. The riser must be calculated keeping in mind the floor-to-floor height<\/strong>, that is the measurement from the top of the pavement floor (extrados) to the ceiling surface (intrados).<\/p>\n In fact, since the spiral staircase wraps around a central post, each step must be at least 2m away from their simmetrical equivalen<\/strong>t on the upper module<\/strong>, so as to ensure an adequate level of safety for users passing through.<\/p>\n Design of a spiral staircase – Minimum distance between two equidistant points – produced with Edificius<\/a><\/p><\/div>\n In small diameter spiral stairs (100\/130 cm) where it is not possible to insert more than 12 steps per revolution, otherwise risking reducing the tread depth too much, the value of the riser will tend to be higher than in straight-run stairs.<\/p>\n Let’s now take a closer look at a case study that we have prepared to provide a practical example for your spiral staircase design.<\/p>\n Let’s assume that we need to design a circular spiral staircase. Having a floor opening with a diameter of 1.30 m, we need to overcome a height difference of 3.00 m<\/strong>.<\/p>\n It is recommended that the diameter of the floor opening is a few centimetres greater than your stair\u2019s diameter so to easily accommodate body movements. In this case, we have determined the diameter of the stairs to be 1.20 m.<\/p>\n First of all, it is necessary to establish the position and width of the arrival landing and the length and position of the path of travel.<\/p>\n It is advisable that the width of a spiral staircase arrival landing<\/strong> is at least equal to the tread width. For this reason, we have designed an arrival landing with a width equal to the stairs radius (in this case 60 cm). We will thus have an equilateral triangle with internal angles equal to 60\u00b0.<\/p>\n For an ideal design, the path of travel<\/strong> should be placed at about 30 cm distance from the handrail. Consequently, for stairs with 1.20 m diameter, we will have a travel path diameter of 0.60 m.<\/p>\n Let\u2019s now calculate the length of the travel path in plan:<\/p>\n 0.60 m x \u03c0 = 1.88 m<\/p>\n to which we need to subtract the space occupied by the arrival landing.<\/p>\n Therefore, the definitive value of the path of travel that can be used for the calculation is 1.88 m \u2013 (1.88 \/ 6) m = 1,57 m.<\/p>\n At this point we can draw an elevation view of the staircase that has been developed in plan view. We can define the path of travel measurement horizontally, that is included between the back and the front landing points (1.57 m) and vertically insert a 2.00m mesurement of the equidistant points on the two staircase modules. By connecting the two ends, we can obtain the actual path of travel equal to 2.54 m (that can be calculated with the Pythagorean theorem).<\/p>\n Next, we can proceed with the calculation of risers and treads.<\/p>\n Finally, we can draw the staircase in plan view to verify a comfortable access and exit from the stairs structure. If the entry point results uncomfortable, we can either rotate the entire staircase, thus also moving the exit point, or change a right-hand to a left-hand stairs direction.<\/p>\n The staircase that we have designed for this case study has a steel structure, with a central post with circular section. The contrasting materials choice, marble and black resin, produces an astonishing final result.<\/p>\n Rendered section of a spiral staircase produced with Edificius<\/a><\/p><\/div>\n Here’s the 3D BIM model of a spiral staircase produced with an architectural BIM design software that you could use as a project example.<\/p>\nWhy chosing a spiral staircase?<\/h2>\n
Types of Spiral Staircases and Advantages<\/h2>\n
Types by Shape<\/h3>\n
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![\"Types](\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2019\/10\/project-of-a-spiral-staircase-types-floor-plans.jpg\" "\\"spial")
Circular Spiral Staircase<\/h4>\n
![\"Technical](\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2019\/10\/Spiral-staircase-design-Floor-plan-architecture-software-Edificius.jpg\" "\\"Spiral")
Square Spiral Staircase<\/h4>\n
Elliptical Spiral Staircase<\/h4>\n
Types by Material<\/h3>\n
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Metal Spiral Staircase<\/h4>\n
Wooden Spiral Staircase<\/h4>\n
Reinforced Concrete Spiral Staircase<\/h4>\n
Spiral staircase dimensions<\/h2>\n
\n<\/strong><\/p>\n![\"Technical](\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2019\/10\/Step-man-stairs_formula-Blondel.jpg\" "\\"Step")
![\"Technical](\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2019\/10\/Spiral-staircase-design-cross-section_architecture-software-Edificius.jpg\" "\\"spiral")
![\"minimum](\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2019\/10\/Spiral-staircase-layout-minimum-distance.jpg\" "\\"How")
Spiral staircase design: a practical example<\/h2>\n
![\"\"](\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2020\/09\/sprial-staircase-cut.jpg\")
3D BIM model download<\/h2>\n
![\"edificius\"](\"\/wp-content\/themes\/enfold-child\/img\/banner_prodotto\/edificius-en.jpg\")
<\/a><\/div>\n![\"edificius\"](\"\/wp-content\/themes\/enfold-child\/img\/banner_prodotto_mobile\/edificius-en.jpg\")
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