QA

Quick Answer: How To Calculate Deck Stairs

What is the formula for deck stairs?

To determine the rise and run of the steps, measure the distance from the floor of the deck to the ground and divide that number by 7.5. The result will be the number of steps the staircase will need (e.g., deck is 112″ from the ground; 112/7.5 = 14.93. Round up to get 15 steps).

How do you calculate rise and run of stairs?

Stair terminology and common building codes Run/Tread: The run or tread is the part of the stairway that a person steps on. Rise/Riser: The rise, or height of a step is measured from the top of one tread to the top of the next tread.

How do I calculate how many steps I need for 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).

How do you calculate stair stringers for a deck?

How do I calculate a stair stringer? Start by finding the overall height that the staircase will be. Decide the height or “rise” you’ll want for each step. Divide the total height of the staircase by the height or “rise” you want for each step.

Can I use 2×10 for stair stringers?

Pressure-treated or cedar 2×10 or 2×12 can be used depending on the depth of the cut-outs you’ll be using. By code you will need a minimum of 3-1/2″ of material left on the stringer after the cut-outs and that area should also be free of large knots which would weaken the stringer.

What is the standard rise and run for deck stairs?

The stair treads should be at least 36 inches wide. Despite these minimum requirements, we recommend that stairs should be at least 48 inches wide so they don’t feel cramped. The maximum allowable stair rise is 7 3/4 inches, and the minimum stair rise is 4 inches.

What is the standard stair rise and run?

The OSHA standard for rise and run of stairs is maximum 9.5″ rise and minimum 9.5″ run (tread depth). The IBC maximum rise of a single stair flight is 12.

What is the code for outdoor steps?

Exterior Stair Construction The rise of the stairs should be between 125 mm (5”) and 200 mm (8”). This is measured from top of a tread nosing to the top of the next tread nosing or landing. The run should be between 210 mm (8 ¼”) and 355mm (14”). Unit run is measured from face of nosing to face of nosing.

What size lumber is used for stair stringers?

The stair stringers are essentially the backbone of your staircase. Always use straight, high-quality, pressure-treated 2x12s for stair stringers. If you are planning on resting the stringer on the ground, make sure the wood has .

How long should a 2×12 stringer be?

cut stringers. The two most common cut-stringer defects that I see are overspanning and overcutting. The minimum recommended size for a deck stair stringer is 2×12, which has a maximum recommended unsupported span of 6 feet.

Do deck stairs need risers?

Most high-end deck projects use closed risers to finish the stairs. They also are often in violation of IRC code for decks over 30″, which maintains that they meet the same requirements as guardrail infill. Stair risers may not have openings present that would allow a 4” diameter sphere to pass through.

What is the standard step height for stairs?

Riser Heights 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.

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 code for stair width?

International Residential Code (IRC) The IRC stairs code states that, to comply with stairway requirements, the minimum width for residential stairs be no less than 36 inches. The stair riser code is up to 7.75 inches, and can not vary more than 3/8 of an inch.

Do you need a railing for 3 steps?

A: Editorial Adviser Mike Guertin replies: Since your stairs will have only three risers, you don’t need to install a handrail. That said, it’s important to count the number of risers accurately.

How many steps require a landing?

– A landing is required every 12′ of vertical stairway rise. – The landing should be at least as wide as the stairway that it serves.

Do exterior stairs need a landing?

Stairways must have a landing, top and bottom, equal to the width of stairs. The minimum dimension measured in the direction of travel shall equal to the width of the stairway, but need not exceed 48” where the stairway has a straight run.

How many steps are in a 4 foot deck?

A four-foot high deck can have a range between 6 and 8 steps.

How do I anchor my deck stairs to the ground?

How to Anchor Deck Stairs to Concrete Use your jigsaw. Notch out the bottom front of the center stair stringers to accept a 2×4 base plate. Make sure your stringers are level. Fasten the base plate to the stair stringers with screws. Locked in place.

Can I use joist hangers for stair stringers?

This will reinforce the stair stringer to rim joist connection and distribute the stair weight more evenly onto the deck framing. Cut them to fit the space perpendicularly between the rim joist and the next interior joist. Use joist hangers to fasten the blocking.