Stair Regulations UK: Building Regulations For Staircases (2024)

Staircases come in all sizes, shapes and materials and can be custom made to suit your property. However, it’s important to make sure that your new staircase not only looks great, but that it’s also safe to use – that’s where stair regulations come in.

Building a staircase is often tough on its own, but UK building regulations make this task even harder. Living up to subjective criteria is not easy, always easy to comply with, but one has no choice whenever it is necessary. Luckily for us, these stair regulations for buildings are fairly straightforward for the most part, making the whole process at least a little bit easier.

in this article

Staircase building regulations in a domestic environment

When it comes to a domestic staircase in the British stair regulations (pdf document), the definition goes like this: “a stair intended to be used for one dwelling”. This is pretty straightforward wording, meaning that one can only use this kind of stairs for one house or flat, and the stairs must be situated in that specific apartment. Because of that, in most building regulations, these are called “private stairs”.

Before we dwell on the specifics of stair regulations in the UK, it is important to note that Scotland has its very own guidelines and principles for stairs, while Wales, Ireland, and England share theirs, or at least when it comes to staircases.

Now let’s take a look at some of the most important details that will help us understand the specific circ*mstances a little bit better. These could very well become the difference between enjoying regulation stairs and paying a hefty fine.

Key details

Stair Regulations UK: Building Regulations For Staircases (1)

Knowing what kind of headroom or winder you can use is very, very important. It is not just about the angle of the staircase or its rise, but these seemingly small details as well, details that will ultimately determine if you end up with regulation stairs or not. If you want to pass spiral staircase building regulations, for example, you will have more homework to do.

  • The rise has to fall between 150 and 220mm.
  • The going must be between 220mm and 300mm.
  • The angle cannot exceed 42 degrees.

These measurements will, of course, be in direct correlation with each other, which means that careful planning is always needed and not just because of the regulations. Ideally, we would like to end up with a staircase that not only passes regulation but is practical too.

Additional restrictions

UK building regulations stairs are no joke. For example, if you want to build a regulation staircase, all risers will have to come at the same size. The only exception is when you build a staircase where a landing separates two sets of flights. In that case, these two flights can have different rises compared to each other.

When it comes to the width, there is no regulated minimum. However, the recommended minimum should be between 800mm and 1000 mm, to allow only to climb that staircase with comfort, but you can actually bring something upon it.


When it comes to the headroom, regulations are once again pretty clear. There must be a minimum of 2000 mm headroom at every stage while going up on a staircase. It’s obviously ideal to have even more, but that is the bare minimum from a regulatory standpoint.

  • If staircases are less than one meter wide, they should have a handrail on at least one side.
  • Staircases more than one meter must have handrails on both sides.
  • The height of handrails should be between 900mm and 100mm.
  • Gaps between the handrails should not be big enough to allow a 100mm sphere to pass through them.


The landings can have two purposes. They either act like a turning point where the staircase changes directions (but continues) or part of the floor at the end of the staircase. Regardless of which you choose, its width has to match the narrowest section of the stairs.

  • There must be a landing at the top and bottom of every staircase.
  • The landing must be wider than the width of the staircase.
  • Landings should be level; however, a ground-floor landing can have a gradient of no more than 1:20.


Stair Regulations UK: Building Regulations For Staircases (2)

The top of the handrails cannot be higher than 1000mm from the staircase, and ideally, it would fall between 900mm and 1000mm. Anywhere with a drop of more than 600mm, they are mandatory. The distance between the spindles cannot be greater than 99mm.

  • You do not need a handrail on the first two steps up
  • All the building’s handrail heights should be between n 900mm and 1000mm.
  • A 100mm diameter sphere cannot pass through any openings.


  • Stair Regulations UK: Building Regulations For Staircases (3)All steps must have the same rise (the gap between one step and the next).
  • The maximum rise of a step should be 220mm.
  • The length of the step (referred to as the ‘going’) should be a minimum of 220mm and a maximum of 220mm.
  • All steps should be level.
  • The edges of the steps, referred to as the lip or nose, should be 16mm.
  • Open rises, which are steps with a gap between them, should be constructed so that a 100mm sphere can’t fit through them.
  • An individual rise must be between 150mm and 220mm
  • An individual going must be between 220mm and 300mm
  • The pitch cannot be greater than 42°


  • All risers must be the same on a flight of stairs. In other words, you cannot have some risers at 200mm and others at 205mm.
  • That said, each flight may have different individual rises on a staircase with a landing.
  • Twice the individual rise plus the going must be between 500mm and 700m (2R +G) and will only create problems in extreme situations.

Need to find professional to build a staircase? We can help! Find A Tradesman

Rises, Goings & Angles

Kite Winders

Stair Regulations UK: Building Regulations For Staircases (4)

Also referred to as an e-z winder, spinner, and various other names, the kite winder is a useful tool for minimizing the space taken up by a staircase with a turn. A kite winder also has rules that must be adhered to. A stair with kite winders normally has a combination of straight treads and winder treads.

The rule for all treads states, “Twice the individual rise plus the going must be 500mm and 700mm”, which can be a problem with 2 kit winder boxes.

To meet building regulations, the winder treads are both equal and greater than the straight threads. However, they will be huge if applying the following rule:

“Twice the individual rise plus the going (2R +G) must be between 500mm and 700mm.”

The problem is, this will be greater than the maximum 700mm required by the building regulations. However, the 2 kite winders would not comply with the regulations, but 2 different kite winders might.

The Inside Tread Dimension:

The building regulations also state that the tread should be 50mm tread width at the narrow end.

Other UK Staircase Building Regulations

  • Doors should not open more than 400mm onto the front of any step.
  • Domestic staircases shouldn’t be more than 36 steps long; another staircase must be installed separated by a landing if you need more length.
  • There must be at least two metres of headroom around all parts of the staircase.
  • There are no regulations for the minimum width of a staircase.
  • For loft conversion staircases, there are some additional building regulations to adhere to: there should be two metres of headroom at the top of the stairs. Since the opening into the loft will mean cutting away some of the joists, supporting timber trimmers should be placed around the opening to transfer the weight of the ceiling.
  • Spiral staircase building regulations are slightly different. If it acts as your main staircase (meaning it serves two or more rooms), a spiral staircase should be 800mm wide with a maximum rise of 220mm; the length of the steps should be at least 190mm. If the staircase is only a secondary one and serves only one room, it should be 60mm wide with a rise of 220mm and a step length of no more than 145mm.
  • The pitch of a domestic staircase (how steep it is) should be a maximum of 42 degrees.

Types of Stairs – Straight, Wide, Arched and Spiral Staircases

Bear all of these regulations in mind when choosing what kind of staircase to install.

  • A straight staircase is the most common and practical option, but you can go for winder staircases that have a 90 and 180-degree turn in them.
  • Arched staircases, which curve gently upwards, are another popular domestic staircase option, while spiral staircases are also popular for aesthetic appeal;
  • Compact stairs can be a good option if you need to save space, but it’s important to make sure that they comply with building regulations.
  • Speak to a staircase installer or architect for more information about what type of staircase will best suit your property.

image credit:

Stair Regulations UK: Building Regulations For Staircases (2024)


What are the Building Regulations for open staircases in the UK? ›

In case you want to build a staircase with open risers, you will have to ensure that a 100mm ball cannot pass through the space. Again, this is meant to protect children from getting stuck in the space. It is important to note that open risers are not allowed on public stairs.

What are the standards for stairs UK? ›

To stay within Building Regulations, a domestic staircase needs a rise of between 190mm and 220mm. Standard risers are around 200mm, so aim for this. The average rise is 2,600mm, which divides easily into 13 200mm risers, or steps. You can now calculate the number of treads.

What are the minimum requirements for stairs? ›

The measurement of 2 R+G is used to ensure the proportion of steps is appropriate. This value ideally should be 600 mm, and always be between 550 mm and 700 mm. The minimum clear width of a stairs is 800 mm as outlined in Technical Guidance Document K of the Building Regulations.

What is the 18 rule for a staircase? ›

The 18 rule is a building code regulation for staircases that obliges the sum of two risers and one tread should equal 18 inches (45.72 cm). This rule was conceptualised thanks to the average stride length of an adult.

What is the 2 staircase rule? ›

Until now, tall buildings in England only require a single staircase. In Scotland, all buildings 18m tall (or seven storeys) have required two staircases since 2019. In February, the mayor of London introduced a rule with immediate effect requiring a second staircase on all new applications of buildings over 30m.

Can I have an open staircase? ›

Known as the “babies head rule” a sphere of 100mm diameter must not be able to pass through ANY gap. This includes spacing of balustrade uprights and gaps between treads. Yet, this is not the whole story – the treads must have an overhang no less than 16mm. This overhang makes it harder for objects to pass through.

What is the standard with of a staircase? ›

Building Codes for Stairs

Stairs must be at least 36" wide with a minimum headroom of 6' 8" Risers must have a maximum height of 7 ¾" and open risers must be 4" high or shorter. Each tread in a stair must have a minimum depth of 10".

What is the minimum landing size for stairs UK? ›

In all cases, stairs must have landings which are at least as big – in length and width – as the width of the flight. This will need to comply with the minimum widths set for the particular staircase type. For example, if the stair width is 1000 mm, then the landing must be at least 1000 mm by 1000 mm in area.

Can a staircase be open on one side? ›

Fully Open– Staircase with no walls on either side. Partially Open / One Wall– Staircase with a wall on one side, and open or with just a railing on the other. Enclosed / Two Wall– Enclosed staircase with walls on both sides and no railing.

What is the rule of 27 for stairs? ›

Any provided handrails cannot protrude more than 4.5 inches into the minimum width. So if a handrail is provided on one side, the minimum clear width is 31.5 inches and if a handrail is provided on both sides, the minimum clear width is 27 inches.

What is the 25 rule for stairs? ›

There are some rules of thumb when planning stairs. One is: “Two risers plus one tread should equal 25 in.” This works well in most circ*mstances.

What are the rules for external stairs in the UK? ›

Outdoor Step Regulations For Dwellings
  • The Standard Outdoor Step Height in the UK. Outdoor step rise: 150-170mm. ...
  • The Standard Outdoor Step Going in the UK. Outdoor step going: 280-425mm. ...
  • Outdoor Step Landings. Outdoor step landing length: 900mm.
May 23, 2023

Can you have open stairs in a kitchen UK? ›

If your kitchen is open plan and there's an exposed staircase leading to it you will have to have a heat detector and you may need to take additional measures - your local building control team will be able to advise what's required.

Do you need planning permission for a staircase UK? ›

“In most cases, you will not need planning permission from your local authority to relocate your staircase, if the new design does not impact the external appearance of your property,” says Claire Pascoe, Senior Designer at Bisca. “If your building is listed, different regulations may apply.

Can you have an open staircase in a kitchen? ›

For example, a staircase providing an escape route from upstairs rooms wouldn't generally be allowed to go through the kitchen. This is because the kitchen is considered a fire risk, and therefore no escape route should lead through it.

Top Articles
Latest Posts
Article information

Author: Pres. Carey Rath

Last Updated:

Views: 5492

Rating: 4 / 5 (61 voted)

Reviews: 92% of readers found this page helpful

Author information

Name: Pres. Carey Rath

Birthday: 1997-03-06

Address: 14955 Ledner Trail, East Rodrickfort, NE 85127-8369

Phone: +18682428114917

Job: National Technology Representative

Hobby: Sand art, Drama, Web surfing, Cycling, Brazilian jiu-jitsu, Leather crafting, Creative writing

Introduction: My name is Pres. Carey Rath, I am a faithful, funny, vast, joyous, lively, brave, glamorous person who loves writing and wants to share my knowledge and understanding with you.