QA

How To Lay Out Steps

What is the formula for laying out stairs?

Determining the Rise You divide the height by 7 inches; if, say, the floor-to-floor distance is 8 feet, 10 inches (or 106 inches), then you’ll need 15 treads (106 divided by 7 equals 15.14). Next, you divide the height by the number of treads (15 into 106), producing the exact tread height (7.06 inches).

What angle should stairs be?

Standard stair angle by application Standard stairs have an angle of 30 to 50 degrees while steep stairs like alternating tread stairs and ship stairs have an angle between 50 and 70 degrees. Ladders have an angle range between 60 and 90 degrees.

How long of a stair stringer do I need?

When ordering stringers, allow about 14 inches of stringer length for each step. Look for straight stock with as few knots as possible. You’ll need at least one stringer for every 16 inches of stair width.

How many stairs do you need to go up 8 feet?

Stair Rise for 8-Foot Ceilings An 8-foot ceiling will need 14 treads. Divide 96-inches (8-feet) by 7-inches to get 13.71 treads, and round up to 14. In this case, you would not round down as you would have one step that is too tall.

What should the rise of a step be?

It’s important to have the right ratio of tread to rise to make going up and down safe and easy. In general, the smaller the rise, the bigger the tread. You can choose what’s comfortable for you but generally outdoor steps have a rise of 5 ½ to 7 inches and a tread of 12 to 18 inches.

How deep should steps be?

The depth (also called tread or run) of each step should be a minimum of 10 or 11 inches depending on the type of stairs. These measurements come from a number of general guidelines which determine this as the starting point for safe stairs.

Can I use 2×12 for stair treads?

Stair treads may be made of a single 2×12, but are often made of two decking boards or 2x6s. A stringer is a wide board, usually a 2×12, that runs at an angle from the landing pad to the deck framing and supports the treads. The stair treads should be at least 36 inches wide.

Is 45 degree stairs too steep?

A standard stair has 11″ treads and 7″ risers. Using those dimensions a stair at 45° would have 7″ treads (too small) with 7″ risers or 11″ treads with 11″ risers (too big). So yes, a 45° stair is too steep and more importantly doesn’t even come close to meeting the building code.

How do I support a stair stringer?

If your stringers are more than 10′ long, we recommend installing a rigid beam at mid-span to add support to the structure. The strength of stair stringers is considerably weakened by the cuts made to create the stair surfaces, and stairs must be.

Are stair stringers 2×10 or 2×12?

It is acceptable and within building code guidelines to use either 2×10 or 2×12 dimensional lumber to create a set of stairs; however, a stair stringer should not be less than 3.5 inches wide at its narrowest point to provide adequate strength for the load the stairs will be supporting.

How long do stairs need to be to go up 10 feet?

For most homes, the length of a flight of stairs is between 9 and 12 feet long. The total length of a flight of stairs for an 8-foot ceiling is approximately 9-feet long. The total length of a flight of stairs for a 10-foot ceiling is approximately 12-feet long.

How many steps does it take to climb 10 feet?

A staircase in a home with 10′ ceilings requires 17 steps. Stairs that have a tread depth of 11” will have a total length of 187”. Stairs with a tread depth of 10” will have a total length of 170”, which is the minimum length.

How many stairs do I need for 10 feet?

As per thumb rule and various building code or IRC, assume standard design, for 12 feet height of staircase, you will need approximately 21 stairs and for 10 feet height you need 19 stairs to go up.

Is an 8 inch step too high?

Building codes in many areas define maximum step height and minimum tread width, but in areas where it is not defined, Council of American Building Officials and International Code Council both recommend the rise to be no more than 7.75 inches and runs to be no less than 10 inches.

What is a comfortable step height?

In the United States, the step height standard should be between 7 or 7 ¾ inches at the most, and no less than 4 inches. You should follow other measurements if given by local building codes. In Canada, the maximum step riser height is 8 ¼ inches.

What is the code for outside steps?

Outdoor stair width code As a means of egress, outdoor stairs must meet all the requirements set forth in IRC section R311. 7.1 Width. Stairways shall not be less than 36 inches in clear width at all points above the permitted handrail heights and below the required headroom height.

What is a comfortable stair rise?

Rule one says that rise plus run (r+R) should equal 18 inches. Why? That’s what most people find to be a comfortable stride on most stairs. You can cheat a bit up or down, but below 17” and more than 19” will result in steps that require strides either too big or too small for most people.

What is the best rise and run for stairs?

On a main stair, the maximum rise should be no more than 8 1/4 inches and the minimum run should be no less than 9 inches. To determine how many steps, or treads, you need, measure from the top of the finished floor on the lower level to the top of the finished floor on the upper level.

What goes first riser or tread?

When installing stairs, install the riser first, and then the tread. Start at the bottom of the stairs and work your way up, alternating risers and treads. The back of each tread will sit flush against the riser. Treads and risers fasten with construction adhesive to the subfloor.