How Big is a Spiral Staircase?

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Spiral staircases are great options for any home or work area. Aside from its unique design, it consumes less floor space and gives it an artistic outlook. However, before settling for these stairs, you have to be sure they are perfect for your design.

While considering my interior outlook, I had to assess the impact of having a spiral staircase in my living area.

As I viewed my floorplan, I thought how much space these stairs would take up in a set position. Thus, I had to research how big a spiral staircase is.

A spiral staircase has a diameter that ranges from 42″ to 76.” Regardless of your stair’s measurement, the opening of the top floor must be bigger than the diameter by two square inches. The size of a spiral staircase also depends on the floor-to-floor height, landing length, footprint, and walking space.

Deciding on the size of a spiral staircase is essential as it affects the general look of your home. With my experience, I have organized the best information about a spiral staircase and all to consider when choosing one. You will find all these in this article.

Where is the best place to have a spiral staircase?


Most times, the term “spiral staircase” summons the thought of a grand house or large worship place. But, these stairs are quite versatile and fit several places. These could range from your regular sitting room or large organizations.

For less fanciful places, spiral staircases make a good substitution for ladders in loft areas.  This makes it easier for little children to access a second floor with less opening for a fall. In the same vein, it reduces the risks of accidents, especially in homes.

Libraries are great places to have a spiral staircase. However, they don’t do much here as you would still need a ladder to access books in other parts of the library.

Spiral stairs are also perfect for decks or patios. Not only do they save space, but they also give the external part of your building a sophisticated appearance. For modern homes, they could add a traditional touch to soften their aesthetic look.

Aside from residential areas and libraries, spiral staircases are perfect for commercial buildings. You can install them internally or externally, depending on the building’s plan.

How Do You Measure a Spiral Staircase?

When constructing stairs, you must consider their measurement. If you are a professional at taking measurements, you can do this yourself. However, it’s advisable to hire the services of an expert to perform this duty.

When measuring for spiral staircases, you must first take note of the floor-to-floor height. Irrespective of where you plan to put your stairs, the height determines the number of steps involved. It also affects the rotation of your stairs.

For instance, an 88″ to 95″ will give you 9 treads, which is approximately 270°. In the same vein, Aa 95″-105.5″ height will give 10 treads, which is a 360° angle of rotation. After you have decided on this, you should consider the well opening.

The opening of a staircase is the space it will need at the upper level. In other words, it is the opening that leads to the upper floor. The hole could be a round or square opening, depending on your preference and structure design.

Irrespective of the stairs’ size, the opening must be wider than the diameter, with only 2 inches. Therefore, if you plan to install a staircase with a 54″ footprint, the well opening should be 56″.

After you have determined the height of your stairs, the diameter comes next. The diameter generally refers to the width of your stairs. If you have a wall opening, your staircase should fit it.

However, if there are no openings, you have a broader choice of deciding the outcome of your spiral staircase. The diameter of your stairs also influences the number of treads. This means that the larger your diameter, the larger the step size and vice versa.

Getting your diameter entails measuring across the staircase, including the rail spacing. Generally, the smallest size of diameter is 3 feet, 6 inches, while the largest is 6 feet.

While your diameter determines the width of the entire staircase, it doesn’t cover the walking space. The walking space is simply the distance from the outer railing to the center pole.

Your walking space depends on the diameter of the staircase. For instance, a diameter of 4 feet 6 inches needs a walking space of 23 inches.

While taking all the facts into consideration, also consider head clearance. A professional will not ignore this factor regardless of how minimal it seems. The head clearance is the height beneath the upper landing. Generally, it must have a minimum value of 2 meters to avoid people bumping their heads.

How Do I Install a Spiral Staircase Outdoor

The process of installing an external spiral staircase is the same as installing one inside your building. But, unlike internal stairs, there are no walls or obstructions to consider, which makes it easier to install.

One of the most important things to consider for external spiral stairs is the weather conditions. Most times, these stairs remain exposed to extreme weather conditions, which makes them deteriorate faster.

Therefore, ensure the materials are suited to withstand the weather irrespective of the temperature.

How Do I Install a Spiral Staircase Outdoors?

The width and walking space of your spiral staircase depend on your preference. While choosing the best design for stairs, ensure they are comfortable. A comfortable staircase gives enough space for footprints and also has ambient space for well opening.

If your stairs are the only path to the upper ground, then it should have a walking space of 26″. For this, the diameter should be at least 5 feet. This is to guarantee safety for children and adults alike.

If you plan on carrying heavy loads up the stairs, you should consider a wider diameter. Nonetheless, the size of your spiral staircase depends on you and the space it’ll take up.

How do you move your furniture up a spiral staircase?

The curved nature of spiral staircases makes it difficult to move large items. It becomes worse if you use a smaller diameter for measurement. Thus, before installing a spiral staircase, you should consider the convenience of moving your belongings.

When moving stuff, the most important element to consider is the well opening. It might be possible to maneuver large furniture through small openings. However, if the well opening was smaller, it wouldn’t go through.

In this case, you seek a better method of moving these large items. You can either dismantle it if possible or hire professional movers to figure it out.

Are Spiral Staircases Safe

Spiral staircases are safe, provided they follow the standard measurements and precautions. The best way to be sure of this is to have a professional team install your stairs.

To ensure safety, there should be a railing around the well opening. Aside from this, you must pay attention to the angle of rotation.

Each step should lie at least 30 degrees to the center, making them wide enough and easy to climb.

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