We are often asked to explain the differences between the types of staircases (spiral, spacesaver, linear or winder stairs) and how the UK Building Regulations are involved. Questions like “can I use a spiral as my main staircase?” or “will a spacesaver staircase be ok to go up to my loft bedrooms?” feature strongly in the list – and these questions are asked by DIYers, builders AND architects. At one time, you could rely on the knowledge from your local Building Control Officers but nowadays they need to have an overview of an unprecedented amount of technical information and regulation details, which are constantly being updated and many have lost or never been able to acquire the specific details of one small section of one of the many Building Regulations.
So, we are always happy to strip it all down to the basics for you. Grab yourself a coffee and read on…
- Space Saver Staircases – can be used to access a single habitable room (plus an ensuite as long as it isn’t the only toilet in the house) but only if you don’t have room for a standard staircase. The individual tread rise should still comply with Building Regs i.e. up to a maximum of 220mm, a straight format is preferred to a curving format, and it should have a handrail on both sides – this can be a staircase balustrade on one side and a simple wall handrail on the other. Spacesavers or Alternate Tread stairs are more compact than standard stairs because part of the tread is cut away so that the treads can closely overlap each other. The treads resemble a paddle which is why they are also called Paddle Stairs. The part of the tread which you place your foot on is still full size but you can only use one foot at a time on each tread. We still come across cases where the local Building Control Officer objects to a spacesaver staircase so it really is down to your local people to approve. The relevant regulations are Building Regulations Part K.
- Spiral Staircases have a British Standard which covers their design – BS5395 Part 2, although this has been superseded it is generally the guide used by Building Control. This defines different categories of use and for the domestic property this will be either Category A Small Private Stair “Internal stair in a dwelling serving one room not being a living room or kitchen” or Category B “similar to Category A but also providing the main access to the upper floor of a dwelling.” The Standard defines the shape and size of the treads, the tread rise and the overall diameter of the staircase. In practice, the results in a 1500mm diameter spiral stair with a maximum tread rise of 220mm for Category A and a Category B staircase will probably have a diameter of 1900-2000mm with the maximum tread rise of 220mm. So, if you have two bedrooms in your loft conversion, you will probably need a spiral staircase with a diameter of 1900mm+. Again, this is all at the discretion of your local Building Control Officer.
- Winder or Linear Staircase is a straight format staircase with one or two quarter turns. The format of this standard type of staircase is covered in the Building Regulations Part K, the main points being a tread going of more than 220mm and a tread rise of a maximum of 220mm. Part K give more detail for the requirements for winders and this document is pretty easy to follow.
- The 100mm Gap Rule is in place to prevent a child under the age of 2 getting their head stuck between the spindles of the balustrade or between any open treads. For our staircases, there is always a RiserBar Kit which fits a neat bar between each tread to cut the gap in half and make sure that this rule is satisfied. For many of the staircases on this website, the balustrading might not comply with the 100mm Gap Rule but we always point this out on the page – and we always advise you to check your project with your local Building Control Department before placing your order.
You’ll find downloads of the relevant parts of both of these documents here. Please feel free to download them and, if you have any questions or queries about them and how they will affect your choice of staircase, please feel free to give us a call or drop us an email.