{"id":5503,"date":"2026-02-06T10:37:14","date_gmt":"2026-02-06T09:37:14","guid":{"rendered":"http:\/\/biblus.accasoftware.com\/en\/?p=5503"},"modified":"2026-02-06T10:37:16","modified_gmt":"2026-02-06T09:37:16","slug":"how-to-design-stairs-criteria-and-examples-to-download","status":"publish","type":"post","link":"https:\/\/biblus.accasoftware.com\/en\/how-to-design-stairs-criteria-and-examples-to-download\/","title":{"rendered":"How to design stairs with a BIM model ready for download"},"content":{"rendered":"<p class=\"sommario\">Read our complete guide on how to design stairs, with general design criteria, renders, DWG CAD drawings and a 3D BIM model ready for you to use<\/p>\n<p><!--more--><\/p>\n<p>In this guide we&#8217;ll be focusing on how to correctly design stairs and analyse the main features of various stairs types.<\/p>\n<p>Below you&#8217;ll be able to download the complete BIM project example of a staircase together with a 3D rendering and the trial version of Edificius, the architectural software used to produce them.<\/p>\n<div id=\"attachment_5755\" style=\"width: 710px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5755\" class=\"wp-image-5755 size-full\" title=\"3D rendering of a staircase - Edificius\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_render-software-BIM-architettura-Edificius.jpg\" alt=\"Staircase-interior-design_render-software-BIM-architecture-Edificius\" width=\"700\" height=\"394\" srcset=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_render-software-BIM-architettura-Edificius.jpg 700w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_render-software-BIM-architettura-Edificius-300x169.jpg 300w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_render-software-BIM-architettura-Edificius-284x160.jpg 284w\" sizes=\"(max-width: 700px) 100vw, 700px\" \/><p id=\"caption-attachment-5755\" class=\"wp-caption-text\">3D rendering of a staircase &#8211; Edificius<\/p><\/div>\n<p><a class=\"downloadedf\" href=\"https:\/\/cloud.usbim.com\/home\/workspaces?workspace_id=24969&amp;folder_id=1458974\">Download the complete 3D BIM model file (in the Edificius native file .edf) with different types of stairs<\/a><\/p>\n<p>Stairs are structural elements that allow the connection between different floors of a building. Generally a staircase is made of:<\/p>\n<ul>\n<li>Steps<\/li>\n<li>Flights<\/li>\n<li>Landings<\/li>\n<\/ul>\n<p><strong>Stair steps<\/strong> are horizontal supports that follow one another upwardly, allowing users to ascend or descend a staircase and pass from one floor of a building to another.<\/p>\n<p>A <strong>stair flight<\/strong> is a run of consecutive stair steps. A staircase can be composed of several stair flights which are separated by landings.<\/p>\n<p>A <strong>landing<\/strong> is a horizontal element that allows the connection between two or more flights. It provides a resting place and allows the access to the different zones of the stairway. There are floor landings (that give access to the different areas of the floor) and intermediate landings\u00a0 (that connect the flights between them).<\/p>\n<p>The vertical portion between each tread on the stair is called <strong>rise<\/strong>\/<strong>riser<\/strong>. The depth of the tread is called <strong>run<\/strong> or <strong>going<\/strong>.<\/p>\n<h2 id=\"staircase-interior-design-types-of-staircase\">Staircase interior design. Types of staircase<\/h2>\n<p>Stairs can be classified by material:<\/p>\n<ul>\n<li>Concrete stairs<\/li>\n<li>Steel stairs<\/li>\n<li>Wooden stairs<\/li>\n<\/ul>\n<p>The most common types of concrete stairs are:<\/p>\n<ol>\n<li>Rampant slab staircase: made by a concrete slab on which steps lay out. Structurally the slab is supported by a starting beam and an arrival beam.<\/li>\n<li>Knee-portal staircase: made by particular emerging beams, called knee-portals, because of its particular \u201cz\u201d- shape on which cantilevered steps are inserted.<\/li>\n<\/ol>\n<p>Staircases may be classified also by slope.\u00a0 According to this criteria, we have:<\/p>\n<ul>\n<li><strong>Ladder stairs<\/strong>, , almost vertical, with steps that can be used as handholdsin case of a very high slope (more than 50\u00b0); for maintenance, occasional or similar uses only.<\/li>\n<li><strong>Common stairs<\/strong>, with a slope angle between 20\u00b0 and 45\u00b0; for private uses, these normally have a larger slope value.<\/li>\n<\/ul>\n<div id=\"attachment_5757\" style=\"width: 339px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5757\" class=\"wp-image-5757 size-full\" title=\"Bifurcated stairs - created with Edificius\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-a-tenaglia-SEZIONE-software-BIM-architettura-Edificius.jpg\" alt=\"Staircase-interior-design_Bifurcated-stairs-SECTION-software-BIM-architecture-Edificius\" width=\"329\" height=\"382\" srcset=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-a-tenaglia-SEZIONE-software-BIM-architettura-Edificius.jpg 329w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-a-tenaglia-SEZIONE-software-BIM-architettura-Edificius-258x300.jpg 258w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-a-tenaglia-SEZIONE-software-BIM-architettura-Edificius-138x160.jpg 138w\" sizes=\"(max-width: 329px) 100vw, 329px\" \/><p id=\"caption-attachment-5757\" class=\"wp-caption-text\">Bifurcated stairs &#8211; created with Edificius<\/p><\/div>\n<h3>Staircase interior design, types of stairs<\/h3>\n<p>When choosing the form of the staircase, the available space and the position that the stairway should take, will influence the choice.<\/p>\n<p>Choosing one model or another, means making the most of a wall space or a corner, or even \u00a0the center of a room.<\/p>\n<p>The form of the staircase in floor plan determines its type which can be a <strong>regular<\/strong> or <strong>irregular polygon<\/strong>, a <strong>circle<\/strong> or an <strong>ellipsis<\/strong>, etc.<\/p>\n<p>Steps should always be perpendicular to the staircase walls in order to concentrate any\u00a0 irregularities along the landings.<\/p>\n<p>The staircase can be configured in plan as:<\/p>\n<ul>\n<li>a rectangular plan, meaning that it has enough space for two parallel flights, that connect with floors or intermediate landings;<\/li>\n<li>a square plan, normally used to make the stairway turn around an elevator shaft;<\/li>\n<li>a circular plan (or helical, in some case), when we talk about spiral stairs.<\/li>\n<\/ul>\n<h2 id=\"indoor-ramp-staircases\">Indoor ramp staircases<\/h2>\n<p>A ramp staircase is commonly used in two situations:<\/p>\n<ol>\n<li>When the stairs lean against a wall<\/li>\n<li>When there is corner space that can be used<\/li>\n<\/ol>\n<p>A staircase ramp can be:<\/p>\n<ul>\n<li>in a straight run, the most commonly used type<\/li>\n<li>with two flights of stairs connected by a turn; they are often composed by the same number of steps interrupted by an intermediate floor (which will be represented on the floor plan as a rectangle or a square)<\/li>\n<li>with two straight flights of stairs, connected by winders (that generate a curvilinear path on the floor plan)<\/li>\n<li>mixed, made by a curved and a straight section<\/li>\n<\/ul>\n<div id=\"attachment_5759\" style=\"width: 460px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5759\" class=\"wp-image-5759 size-full\" title=\"Rectangular-shaped floor plan - produced with Edificius\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-pianta-rettangolare-software-BIM-architettura-Edificius.jpg\" alt=\"Staircase-interior-design-rectangular-floor-plan-software-BIM-architecture-Edificius\" width=\"450\" height=\"578\" srcset=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-pianta-rettangolare-software-BIM-architettura-Edificius.jpg 450w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-pianta-rettangolare-software-BIM-architettura-Edificius-234x300.jpg 234w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-pianta-rettangolare-software-BIM-architettura-Edificius-125x160.jpg 125w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><p id=\"caption-attachment-5759\" class=\"wp-caption-text\">Rectangular-shaped stairs floor plan &#8211; produced with Edificius<\/p><\/div>\n<h2 id=\"indoor-spiral-staircases\">Indoor spiral staircases<\/h2>\n<p>Spiral, helical or circular stair type configurations are usually suggested when the staircase is located at the center of the room. There are two types of spiral stairs:<\/p>\n<ul>\n<li>with one central supporting pillar to which all the radiating steps are attached, also called newel\u00a0 or central pole, fixed to the ground and to the ceiling, with a load-bearing function<\/li>\n<li>without the central supporting column, when the whole structure is fixed to the ground and to the arrival point.<\/li>\n<\/ul>\n<p>Spiral staircases are very space efficient, so they are recommended when there are space limitations. In the design floor plans, spiral staircases can be represented by a spiral, a square or a helical layout drawing.<\/p>\n<div id=\"attachment_5760\" style=\"width: 460px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5760\" class=\"wp-image-5760 size-full\" title=\"Spiral staircase floor plan - produced with Edificius\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-chiocciola-software-BIM-architettura-Edificius.jpg\" alt=\"Staircase-interior-design-Spiral-stairs-software-BIM-architecture-Edificius\" width=\"450\" height=\"456\" srcset=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-chiocciola-software-BIM-architettura-Edificius.jpg 450w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-chiocciola-software-BIM-architettura-Edificius-296x300.jpg 296w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-chiocciola-software-BIM-architettura-Edificius-80x80.jpg 80w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-chiocciola-software-BIM-architettura-Edificius-36x36.jpg 36w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-chiocciola-software-BIM-architettura-Edificius-158x160.jpg 158w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><p id=\"caption-attachment-5760\" class=\"wp-caption-text\">Spiral staircase floor plan &#8211; produced with Edificius<\/p><\/div>\n<h2 id=\"aspects-to-consider-when-choosing-a-staircase-type\">Aspects to consider when choosing a staircase type<\/h2>\n<ul>\n<li>The difference between the two floors to connect: if less than 250 cm, a straight run of stairs can be the solution; if greater than 300 cm, an angled staircase can be used; for greater heights, a staircase with a mid-landing, that interrupts its rise, is recommended<\/li>\n<li>The space that the staircase will occupy on the floor<\/li>\n<li>The weight of the staircase and the load bearing structures<\/li>\n<li>The windows and door layout, and other important elements, that should be left free, in order to avoid obstructions of access routes and entrances<\/li>\n<li>The position of the staircase: located in the corner, leaning against a wall or situated in the middle of a room.<\/li>\n<\/ul>\n<h2 id=\"internal-staircase-design-offset\">Internal staircase design, offset<\/h2>\n<p>The distance between the last riser of the first ramp and the first riser of the second ramp is defined as offset.<\/p>\n<p>The offset is a &#8216;structural artifice&#8217; that guarantees a series of advantages (both aesthetic and functional) and a continuity of the handrail. From the aesthetic point of view, the alignment between the intrados of the ramps and the intrados of the landing is ensured by the offset.<\/p>\n<p>The continuity of the handrail inside a staircase in a building is important not only to ensure users\u2019 safety on the staircase, but also because it offers the possibility, in case of disabled people, to mount a stairlift.<\/p>\n<p>In the figure below, the part highlighted in red (consisting of screed + cladding) is equal to half of the riser: the result obtained is just a 0 offset (the last rise of the arrival ramp &#8211; riser 1- is perfectly aligned with the first raising of the starting ramp &#8211; raising 2).<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-5761 size-full\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Sfalsamento-nullo.jpg\" alt=\"Staircase-interior-design_Zero-offset\" width=\"700\" height=\"294\" srcset=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Sfalsamento-nullo.jpg 700w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Sfalsamento-nullo-300x126.jpg 300w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Sfalsamento-nullo-381x160.jpg 381w\" sizes=\"(max-width: 700px) 100vw, 700px\" \/><\/p>\n<p>&nbsp;<\/p>\n<h2 id=\"factors-to-consider-when-designing-a-staircase\">Factors to consider when designing a staircase<\/h2>\n<p>When designing a staircase some factors should be considered:<\/p>\n<ul>\n<li>All the steps on the same flight must be identical<\/li>\n<li>Any stairway that has more than 15 steps have to incorporate a landing in between<\/li>\n<li>The width of each landing must not be less than the width of the ramp<\/li>\n<li>When possible, use of straight stair flights should be preferred<\/li>\n<\/ul>\n<div id=\"attachment_5762\" style=\"width: 252px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5762\" class=\"wp-image-5762 size-full\" title=\"Linear staircase floor plan - produced with Edificius\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-lineare-software-BIM-architettura-Edificius.jpg\" alt=\"Staircase-interior-design_Staight-stairs-software-BIM-architecture-Edificius\" width=\"242\" height=\"705\" srcset=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-lineare-software-BIM-architettura-Edificius.jpg 242w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-lineare-software-BIM-architettura-Edificius-103x300.jpg 103w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-lineare-software-BIM-architettura-Edificius-55x160.jpg 55w\" sizes=\"(max-width: 242px) 100vw, 242px\" \/><p id=\"caption-attachment-5762\" class=\"wp-caption-text\">Linear staircase floor plan &#8211; produced with Edificius<\/p><\/div>\n<h2 id=\"width-of-flights\">Width of flights<\/h2>\n<p>When deciding the width of the stairs, the maximum number of users that ascend and descend in the same time and the type of use should be considered too.<\/p>\n<p>The width of the stairs, as well as the width of the hallways, shall be dimensioned according to the maximum number of people that could make use of them.<\/p>\n<p>The maximum flow of people shall be calculated in the hypothesis of a contemporary escape\/exit of all the persons that live, work, or carry out activities in the building and have access to the stairs and ramps.<\/p>\n<p>In case of public buildings and places open to the public, the width of the stairs in relation to the maximum capacity exit, as well as the most important technical requirements (such as: \u00a0steepness of stairs, or rise-to-going ratio, flooring characteristics, etc.) are regulated by the national building codes.<\/p>\n<p><strong>For indoor stairs, must have flights with minimum clear widths of 80 cm, in case of spiral stairs the diameter\u00a0 must be at least 110cm. The slope of the stairs must have a pitch angle between 30\u00b0 and 60\u00b0<\/strong>.<\/p>\n<h2 id=\"barriers-and-railings\">Barriers and Railings<\/h2>\n<p>Gaps larger than 10 cm between balusters and the handrail must be avoided (vertical and horizontal elements), while the handrail must be set at 90 cm in height from the treads.<\/p>\n<p>To avoid access of small children to stairs or balconies, special wooden or metallic safety gates may be adopted. These kind of gates may have manual, electronic or key-lock opening mechanisms.<\/p>\n<div id=\"attachment_5763\" style=\"width: 710px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5763\" class=\"wp-image-5763 size-full\" title=\"L-shaped stairs floor plan - produced with Edificius\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-L-software-BIM-architettura-Edificius.jpg\" alt=\"Staircase-interior-design-L-shaped-stairs-software-BIM-architecture-Edificius\" width=\"700\" height=\"508\" srcset=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-L-software-BIM-architettura-Edificius.jpg 700w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-L-software-BIM-architettura-Edificius-300x218.jpg 300w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne-Scala-L-software-BIM-architettura-Edificius-220x160.jpg 220w\" sizes=\"(max-width: 700px) 100vw, 700px\" \/><p id=\"caption-attachment-5763\" class=\"wp-caption-text\">L-shaped stairs floor plan &#8211; produced with Edificius<\/p><\/div>\n<h2 id=\"weight-carrying-capacity\">Weight carrying capacity<\/h2>\n<p>The Weight carrying capacity that a staircase must be able to withhold is 400 kg per square meter.<\/p>\n<h2 id=\"steepness-risers-and-treads\">Steepness &#8211; Risers and Treads<\/h2>\n<p>While going to design risers and treads, the difference of level should be considered.<\/p>\n<p>Generally, riser heights should be set between 15 and 17 cm (max 20 cm for service stairs), and between 13 and 15 cm for public buildings (hospitals, schools); while the tread depth calculation is related to the users physical effort necessary to overcome the riser\u2019s extension in height.<\/p>\n<p>Usually the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Fran%C3%A7ois_Blondel\" target=\"_blank\" rel=\"noopener noreferrer\"><strong>Blondel<\/strong><\/a> formula is used:<\/p>\n<p style=\"text-align: center;\"><strong>2r + t = 62 \u00f7 64 cm<\/strong><\/p>\n<p>where:<\/p>\n<p>r represents the riser<\/p>\n<p>t represents the tread<\/p>\n<p>For private stairs in dwellings the relationship between riser and tread dimensions can be increased:<\/p>\n<p>2r + t = \u00f7 65 (with max value of r = 23 cm)<\/p>\n<p>Usually, a maximum of 15 treads for each flight of stairs should not be exceeded, although, in certain cases, especially for restoration projects, a higher number of treads is suggested instead of having excessively high risers, making stair ramp ascent more comfortable for its users avoiding factors relating to excessive steepness. In conclusion, treads with rounded edges are more practical and safe in case of intense usage.<\/p>\n<div id=\"attachment_5764\" style=\"width: 460px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5764\" class=\"wp-image-5764 size-full\" title=\"Bifurcated staircase floor plan - produced with Edificius\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-a-tenaglia-PIANTA-software-BIM-architettura-Edificius.jpg\" alt=\"Staircase-interior-design-Bifurcated-stairs-FLOOR-PLAN-software-BIM-architecture-Edificius\" width=\"450\" height=\"422\" srcset=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-a-tenaglia-PIANTA-software-BIM-architettura-Edificius.jpg 450w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-a-tenaglia-PIANTA-software-BIM-architettura-Edificius-300x281.jpg 300w, https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Progettazione-scale-interne_Scala-a-tenaglia-PIANTA-software-BIM-architettura-Edificius-171x160.jpg 171w\" sizes=\"(max-width: 450px) 100vw, 450px\" \/><p id=\"caption-attachment-5764\" class=\"wp-caption-text\">Bifurcated staircase floor plan &#8211; produced with Edificius<\/p><\/div>\n<h2 id=\"how-to-design-stairs-with-a-bim-software\">How to design stairs with a BIM software<\/h2>\n<p><img decoding=\"async\" class=\"size-full wp-image-39566 aligncenter\" src=\"https:\/\/biblus.accasoftware.com\/en\/wp-content\/uploads\/sites\/2\/2018\/11\/Design-of-interior-scales_executive-plan-software-BIM-architecture-Edificius.jpg\" alt=\"\" width=\"700\" height=\"394\" \/><\/p>\n<p style=\"text-align: left;\"><a class=\"downloadedf\" href=\"https:\/\/cloud.usbim.com\/home\/workspaces?workspace_id=24969&amp;folder_id=1458974\">Download the 3D BIM model (.edf file format) of the Bifurcated stairs project<\/a><\/p>\n<p style=\"text-align: left;\"><a class=\"downloadifc\" href=\"https:\/\/cloud.usbim.com\/home\/workspaces?workspace_id=24969&amp;folder_id=1458974\">Download the IFC model of the Bifurcated stairs project<\/a><\/p>\n<h2 id=\"frequently-asked-questions-about-the-design-of-internal-stairs\">Frequently Asked Questions about the Design of Internal Stairs<\/h2>\n<h3>What are the general criteria for designing an internal staircase?<\/h3>\n<div>\n<p>Designing an internal staircase requires attention to several factors: the available space, the choice of type (such as straight or spiral), the correct combination of rise and tread according to the formula 2a + p = 63 cm, compliance with current regulations, and harmony with the aesthetics and functionality of the environment, also considering elements such as the handrail and the arrangement of doors and windows.<\/p>\n<h3>What are the main types of internal stairs?<\/h3>\n<p>Stairs are distinguished based on the materials used (reinforced concrete, steel, wood), the slope (ladder, technical, common), the shape in plan (rectangular, square, circular), and the configuration (straight, spiral, winder, etc.).<\/p>\n<h3>How is the offset between the flights of a staircase calculated?<\/h3>\n<p>The offset is the distance between the last rise of the first flight and the first of the next. It can be zero, forward, or backward. It is considered zero when the distance equals half the rise (d = a\/2), a condition in which the two rises are perfectly aligned.<\/p>\n<h3>What is the minimum width of an internal staircase?<\/h3>\n<p>The recommended minimum width for an internal staircase is 80 cm. For spiral stairs, the minimum diameter is 110 cm. These values may vary based on the intended use and the number of people who will use the staircase.<\/p>\n<h3>What is the correct formula for designing rise and tread?<\/h3>\n<p>The formula 2a + p = 63 cm, known as Blondel&#8217;s rule, is used. For residential environments, it can go up to 65 cm. Generally, the ideal rise is less than 19 cm, while the tread should be about 30 cm.<\/p>\n<h3>What protections should be provided for an internal staircase?<\/h3>\n<p>Internal stairs must have adequate protections such as continuous handrails, sturdy and safe guardrails, and in some cases, anti-slip elements, especially in the presence of children or people with mobility difficulties.<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"international-product-banner-desktop\" style=\"text-align: center;\"><a class=\"product-banner-link\" href=\"https:\/\/www.accasoftware.com\/en\/3d-building-design-software\" target=\"_blank\" rel=\"noopener\"><img decoding=\"async\" src=\"\/wp-content\/themes\/enfold-child\/img\/banner_prodotto\/edificius-en.jpg\" alt=\"edificius\" \/><\/a><\/div>\n<div class=\"international-product-banner-mobile\" style=\"text-align: center;\"><a class=\"product-banner-link\" href=\"https:\/\/www.accasoftware.com\/en\/3d-building-design-software\" target=\"_blank\" rel=\"noopener\"><img decoding=\"async\" src=\"\/wp-content\/themes\/enfold-child\/img\/banner_prodotto_mobile\/edificius-en.jpg\" alt=\"edificius\" \/><\/a><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Read our complete guide on how to design stairs, with general design criteria, renders, DWG CAD drawings and a 3D BIM model ready for you to use<\/p>\n","protected":false},"author":12,"featured_media":40398,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"keyword_en":"","keyword_es":"","keyword_fr":"","keyword_de":"","keyword_ptb":"","_note_content":"","footnotes":""},"categories":[46],"tags":[5049,203,4934,5193,5216,5255,146,5088],"class_list":["post-5503","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bim-project-example","tag-acca-edificius","tag-focus012","tag-newsletter-197","tag-newsletter-377","tag-newsletter-398","tag-newsletter-432","tag-newsletter-82","tag-newsletter-intro05"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.8 (Yoast SEO v27.8) - 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