Deck Stair Code in Texas: Rise and Run, Landings, Handrails and Cost (2026)

Most deck stair guides skip which code book their numbers come from, and around Dallas that matters: the cities here are on different editions of the International Residential Code (IRC). This guide gives every stair number, says where it comes from, and shows what it means for a 30, 48 or 72 inch high deck.

The values below come from the City of Dallas ordinance, the American Wood Council's DCA 6 deck guide, county copies of the code and Fine Homebuilding, since the ICC's own text could not be opened. Your city's inspector has the final say.

Deck stair code requirements at a glance

Most deck stairs must have risers of 7¾ inches or less, treads of at least 10 inches, at least 36 inches of width, and a handrail once there are four or more risers. Here is every number in one place, with its source.

The core numbers (7¾ inch riser, 10 inch tread, 36 inch width, 6 ft 8 in headroom, 34 to 38 inch handrail, 36 inch landing) are the same in the 2021 and 2024 sources we checked. What changed between editions is mostly where they sit in the book.

What the 2024 IRC (R311.7, now R318.7) requires for deck stair risers, treads, handrails, landings and guards

In the sources we checked, the 2024 IRC keeps the core stair numbers from 2021 but moves the sections: stairways went from R311.7 to R318.7, handrail height moved to R320, and guards moved from R312 to R321. So if you see "2024 IRC R311.7" online, it mixes the old section number with the new edition.

The 2021 section numbers come from the Stairway Manufacturers' Association's illustrated guide to the 2021 IRC. A Texas city shows the same shift: the City of Austin's draft 2024 IRC redline amends the egress door section as R318.2, which was R311.2 in 2021.

Texas residential building code adoption for deck stairs: Dallas, Plano, Frisco and McKinney (2025 to 2026)

Texas leaves the choice to each city. State law sets the IRC as it existed on May 1, 2012 as the baseline for city residential codes, and lets each city adopt later editions with its own amendments. That is why Dallas and its suburbs are on different books today.

Dallas enforces the 2021 ICC codes, effective May 12, 2023. It changed only the riser and tread rules; width, headroom, landings, handrails, guards and the deck chapter (R507) follow the 2021 IRC.

Plano adopted the 2024 IRC, and its codes page labels the set "2024 Codes (Effective August 1)". Its amendments have no stair, handrail, guard or deck framing changes.

Frisco lists the 2024 IRC with local amendments (Ordinance 2026-01-10). We did not review those amendments, so ask the city whether any touch stairs.

McKinney moved to adopt the 2024 IRC from October 1, 2025; confirm with the city. The draft ordinance adopts the NCTCOG regional amendments, but the city's records show no recorded vote, and we could not check whether those regional amendments change any stair rule.

The state's licensing agency also moved to the 2024 editions in 2026, but for your deck, go by what your city enforces.

Stairs and the permit

In Dallas, a deck skips a permit only if it is 200 square feet or less, no more than 30 inches above grade at any point, not attached, clear of service wires, and does not serve the exit door required by R311.4. Stairs from the back door down to the yard usually mean the deck serves that door, so plan on a permit. Whatever the city, ask which edition applies when you apply. See when a Dallas deck needs a permit.

Rise and run: riser height, tread depth, nosing, width and headroom

Keep every riser at 7¾ inches or less and every tread at 10 inches or more, and keep them within 3/8 inch of each other from the top step to the bottom one.

Risers

Dallas's amendment says the riser height "shall be not more than 7 ¾ inches," measured straight up between the leading edges of the treads. In a single flight, the tallest riser may be no more than 3/8 inch taller than the shortest. Risers must be vertical or slope back no more than 30 degrees.

Open risers (the gap between treads) are allowed, but where the stair is more than 30 inches above the ground below, the opening must not let a 4 inch ball through. DCA 6's stair drawing sets the same 4 inch limit for open risers, without the 30 inch condition.

There is no minimum rise in the IRC, though Fine Homebuilding suggests at least 4 inches as good practice.

Treads and nosing

Dallas requires treads of at least 10 inches, measured from nosing to nosing, varying by no more than 3/8 inch in a flight.

DCA 6 calls for a nosing (the front lip of the tread) of 3/4 to 1-1/4 inches, with nosings within 3/8 inch of each other. Fine Homebuilding notes that no nosing is required if the treads are 11 inches or deeper.

The Dallas "private steps" exception

Dallas added a line that most guides miss: "private steps and stairways serving an occupant load of less than 10" may use an 8 inch maximum riser and a 9 inch minimum tread. The ordinance does not define private steps or say whether a deck stair counts. The inspector decides whether it applies, so design to 7¾ and 10 inches unless the city confirms otherwise in writing.

The 3/8 inch rule covers the bottom riser too. If the soil at the foot of the stair settles or heaves, that riser changes height, which is why the bottom of the stair needs a real footing (see below).

Width and headroom

Deck stairs must be at least 36 inches wide above the handrail and have at least 6 feet 8 inches of headroom above the nosings. At handrail height the width can narrow to 31½ inches with one handrail or 27 inches with two, because Fine Homebuilding notes a handrail can project up to 4½ inches into the width from each side. DCA 6 also requires at least 36 inches.

Decks.com recommends at least 48 inches for comfort. Check headroom any time a stair runs under an upper deck or a cover beam.

How many steps does my deck need? (worked examples)

Divide the deck height by 7¾ and round up to get the number of risers; the treads are one fewer. A 48 inch high deck needs 7 risers and 6 treads, about 5 feet of run, plus a 3 foot landing at the bottom.

Calculated from the Dallas 7¾ inch maximum riser and 10 inch minimum tread: 30 ÷ 7.75 = 3.9, 48 ÷ 7.75 = 6.2 and 72 ÷ 7.75 = 9.3, each rounded up. Run is treads times 10 inches.

On the 30 inch deck, the 4 risers trigger a handrail, even though a deck exactly 30 inches high needs no guard on the deck itself, because the IRC guard rule starts at more than 30 inches. DCA 6, though, calls for a stair guard when the stair's total rise is 30 inches or more, so ask your builder which rule the plans follow.

Plan the yard space too. A 48 inch deck needs about 5 feet of run plus at least 3 feet of landing, so roughly 8 feet out from the deck edge (calculated).

For 9 and 12 foot decks, see the stair layouts for a second-story deck. For short runs between platforms, see steps between deck levels.

Landings at the top, bottom and middle of deck stairs

Every flight needs a landing at the top and the bottom, as wide as the stair and at least 36 inches deep, and a tall stair needs a landing partway up once the rise passes about 12 feet.

The 2024 exceptions for short deck stairs

The 2024 IRC text (R318.7.6) has two exceptions that matter for decks:

• At an exterior door, no top landing is needed for an exterior stair of not more than two risers, as long as the door does not swing over the stair.
• Exterior stairs to grade with three or fewer risers serving a deck, porch or patio need a bottom landing only 36 inches wide, as long as the stair is not the required way to grade from the required exit door.

These are 2024 text, relevant in Plano, Frisco and McKinney. We could not confirm the deck exception exists in the 2021 edition Dallas uses, so don't count on it there.

When a stair needs a landing partway up

Under DCA 6, a stair that rises more than 12 feet needs a landing partway up; the IRC allows up to 12 feet 7 inches. DCA 6 is the stricter of the two, and it adds that the landing must be built as a freestanding deck (not hung from a ledger). An intermediate landing can also be used to shorten a long stringer span.

What counts as a bottom landing

The code does not list materials, but the landing slope has to be measurable. A 2009 JLC article written on the 2009 IRC says loose gravel, dirt or grass can't have their slope measured, while concrete, flagstone, pavers or brick can. The same article limits landing slope to 1/4 inch per foot. Where a concrete landing sits against the house and has to drain away from the foundation, Fine Homebuilding notes the current code allows up to 1 inch over 20 inches.

Decks.com recommends a bottom pad of at least 36 by 36 inches in concrete of at least 2,500 psi. If you want the pad to match a stone walkway or patio, a flagstone or paver landing is one option to discuss with your builder.

Handrails: height, grip size and continuity

Once a deck stair has four risers, it needs a handrail on at least one side, 34 to 38 inches above the nosings, and the rail has to be something a hand can wrap around.

Grip size

The 2021 IRC (R311.7.8.5, as published by Anderson County, South Carolina) sets two handrail types:

• Type I: a round rail 1¼ to 2 inches in outside diameter, or a non-round rail with a perimeter of 4 to 6¼ inches and a cross-section no bigger than 2¼ inches.
• Type II: a rail with a perimeter over 6¼ inches, which needs a finger recess on both sides that starts within 3/4 inch of the top and is at least 5/16 inch deep.

That is why a wide, flat top rail on a stair guard usually doesn't count as the handrail: it is wider than the 2¼ inch cross-section limit. In that case, plan a separate graspable handrail.

Continuity and strength

• DCA 6 says the handrail must run continuously from a point directly over the lowest riser to a point over the highest riser and return to the guard at each end (a 2021 IRC handout from Des Moines also allows a return to a wall, post or walking surface). Guard posts may interrupt it at a turn.
• DCA 6 calls for at least 1½ inches of clear space behind the rail, and a smooth, decay or corrosion resistant rail.
• Handrails must resist a 200 pound load in any direction. Fine Homebuilding notes that since the 2021 IRC, guards only have to resist that load outward and downward.

For rail products and prices, see stair railing and graspable handrail options.

Guards on stair sides (short version)

If the stair is more than 30 inches above the ground, its open side also needs a guard. Under the 2021 IRC and DCA 6, that guard must be at least 34 inches above the nosings, with no gap that passes a 4⅜ inch ball.

The triangle formed by the riser, tread and bottom rail must not pass a 6 inch ball, and DCA 6 spaces stair guard posts no more than 6 feet apart. A guard stops a fall off the side; a handrail is what you hold. A stair often needs both.

We could not confirm the 2024 IRC stair guard height, so check it with your city. Guard height, openings and post attachment are covered in deck railing height code.

Stringers and treads: spans, spacing and attachment (DCA 6)

DCA 6 calls for 2x12 stringers, at least three of them if they are cut, spaced no more than 18 inches apart, with a cut stringer spanning no more than 6 feet.

DCA 6 is the American Wood Council's industry deck guide, based on the 2015 IRC. It is not Dallas law, but it gives deck-specific stair details the code itself doesn't spell out.

• Size: all stringers at least 2x12.
• Cut stringers: maximum span 6 feet, with at least 5 inches of solid wood left below the cuts.
• Solid stringers (treads sit on ledgers instead of notches): maximum span 13 feet 3 inches, spaced no more than 36 inches apart with 2x4 tread ledgers.
• Longer spans: add a 4x4 post notched and bolted to the stringer with two 1/2 inch through-bolts, on a footing 12 inches round or 10 inches square and 6 inches thick, or add a landing.
• Treads (Southern pine, Table 6): 2x4 or 5/4 boards on cut stringers, 2x8 on solid stringers.
• Fastening: two 8d threaded nails or two #8 screws at least 2½ inches long per stringer.
• Top connection: a sloped joist hanger with at least 625 pounds of vertical capacity.

Composite treads follow the decking maker's stair span rules, not the wood table, so ask your builder which product and spacing the plans use.

A 72 inch deck shows why spans matter. Its 9 treads at 10 inches make a 7 foot 6 inch run (calculated), which is more than the 6 foot maximum span DCA 6 allows a cut stringer (its drawing measures that span horizontally), so ask your builder how the plan handles it: a mid-support post, solid stringers or a landing.

The footing at the bottom of deck stairs in Dallas clay

Stair stringers should land on posts and footings at least 12 inches into undisturbed soil, not on a patio slab that isn't founded that deep.

DCA 6 says that where the stair meets the ground, the stringers attach to stair guard posts that bear on footings set on solid ground at least 12 inches below the undisturbed surface, with the stringers resting on a 2x4 bearing block on the post. It states that stringers shall not bear on new or existing concrete pads or patios that aren't founded that deep. If no stair guard is required, the posts may stop below the bottom tread.

Dallas's own amendment (R403.1.4) also puts exterior footings at least 12 inches below undisturbed ground.

The landing pad can still be concrete or stone; it just shouldn't be what holds up the stair. A pad floating on clay moves with the soil, which is how a bottom riser ends up out of line. For how Dallas clay behaves and how deep to go, see deck footings in Dallas clay.

Lighting deck stairs: what the code asks for

The code asks for a light at the top landing of exterior stairs. DCA 6 adds that the switch should be inside the house, and motion or timer switches are fine.

Fine Homebuilding's Glenn Mathewson explains that full stair lighting was dropped in the 2015 edition, and the 2024 IRC (R325.7) only requires the top landing to be lit. His examples of sources that can work include a porch light switched from inside, low-voltage lights, or a solar light with automatic controls.

Lights in the risers or posts are a design choice, not a code requirement.

How much do deck stairs cost per step?

National guides put deck stairs at $75 to $450 per step installed (Fixr, 2023) and about $1,400 to $2,600 for a typical set (HomeGuide, 2026). We found no Dallas-only stair price, so every figure below is national.

Worked example: the 48 inch deck

The 48 inch deck above has 6 treads. At Fixr's $75 to $450 per step installed, that is $450 to $2,700; at Advantage Lumber's $150 to $300, it is $900 to $1,800 (calculated from each source's national range, counting treads as steps). Compare HomeGuide's $1,400 to $2,600 per set and Inch Calculator's $1,380 to $2,520 for an 8 step stair. The sources don't say whether a "step" means a tread or a riser.

Handrails on both sides, the bottom landing and stair lighting are extra, and we found no sourced price for a landing pad or stair lights. Porch step prices are in our front porch steps cost guide, and the full deck picture is in the Dallas deck cost guide. Archetex Outdoor Design Co. gives a written price for your stairs after a free site visit.

What to ask your builder about the stairs

1. Which code edition does my city enforce? Dallas is on the 2021 IRC; Plano and Frisco are on the 2024 IRC.
2. Is the riser and tread layout drawn on the plans?
3. How big is the bottom landing, and what is it made of? At least 36 inches deep, on a surface whose slope can be measured.
4. Which handrail, and what grip size?
5. What stringers, how far apart, and which hangers?
6. What holds up the bottom of the stair? Posts and footings, not the patio slab.
7. Where is the top-landing light and its switch?
8. Is the permit included? Stairs from the back door usually mean one in Dallas.

If you want someone to measure your deck height and lay out the stairs before you get prices, see our Dallas deck builder page.