Stair Code Requirements (IRC, IBC, OSHA, ADA)
Everything the stair calculators check, explained: the exact riser, tread, headroom, width, handrail and guard limits — for homes, commercial buildings, workplaces and accessibility.
What the stair calculators check
Every Stairs Calc tool checks your dimensions against the building code you select. The four US codes cover different situations, and four international codes are included for readers outside the US. The limits below are what the Code panel enforces — but local jurisdictions adopt and amend codes, so always confirm against your local adopted edition before you build.
The limits, side by side
86 building codes across 6 regions. The 8 US/UK/EU codes are primary-source verified; international rows are indicative — confirm against your locally adopted code.
Swipe the table sideways to see all 11 metrics →
| Code | Max riser | Min riser | Min run (going) | Uniformity tolerance | Min headroom | Min width | Handrail height | Guard height | Guard trigger (drop) | Baluster max sphere | Max rise between landings |
|---|---|---|---|---|---|---|---|---|---|---|---|
| United States | |||||||||||
| US – Accessibility (ADA) | 7" | 4" | 11" | 3/8" | 6' 8" | 36" | 34"–38" | — | — | — | — |
| US – Commercial (IBC) | 7" | 4" | 11" | 3/8" | 6' 8" | 44" | 34"–38" | 42" | 30" | 4" | 12' |
| US – Residential (IRC) | 7 11/16" | — | 10" | 3/8" | 6' 8" | 36" | 34"–38" | 36" | 30" | 4 3/8" | 12' 7" |
| US – Workplace (OSHA) | 9 1/2" | — | 9 1/2" | — | 6' 8" | 22" | 30"–38" | 42" | — | — | — |
| Europe | |||||||||||
| Albania low confidence | 8 1/4" | 5 1/2" | 11 7/16" | — | 6' 2 13/16" | 35 7/16" | 35 7/16"–39 3/8" | 35 7/16" | — | — | 8' 3 3/16" |
| Austria high confidence | 7 1/16" | — | 10 5/8" | — | 6' 10 11/16" | 47 1/4" | 35 7/16"–43 5/16" | 39 3/8" | — | 4 3/4" | 11' 9 3/4" |
| Belarus medium confidence | 5 7/8" | — | 9 13/16" | — | 6' 6 3/4" | 35 7/16" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | 8' 10 5/16" |
| Belgium medium confidence | 7 1/16" | — | 7 7/8" | — | — | 31 1/2" | 35 7/16"–39 3/8" | 43 5/16" | — | 4 5/16" | — |
| Bosnia and Herzegovina low confidence | 7 1/2" | — | 9 13/16" | — | 7' 2 5/8" | 43 5/16" | 35 7/16"–39 3/8" | 39 3/8" | — | 4 3/4" | 11' 2 5/8" |
| Bulgaria medium confidence | 8 11/16" | — | 9 13/16" | — | 6' 6 3/4" | 47 1/4" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 9/16" | 3' 11 1/4" |
| Croatia medium confidence | 7 1/2" | — | 9 13/16" | — | 6' 10 11/16" | 43 5/16" | 35 7/16"–35 7/16" | 39 3/8" | — | 5 1/2" | — |
| Cyprus high confidence | 7 1/16" | 5 5/16" | 11" | — | 6' 10 11/16" | 47 1/4" | 27 9/16"–35 7/16" | 43 5/16" | — | 3 15/16" | 10' 7 9/16" |
| Czechia high confidence | 7 1/2" | 5 7/8" | 8 1/4" | — | 6' 10 11/16" | 35 7/16" | 35 7/16"–47 1/4" | 39 3/8" | — | 4 3/4" | 10' 7 9/16" |
| Denmark medium confidence | 7 1/16" | — | 9 13/16" | — | 6' 10 11/16" | 39 3/8" | 31 1/2"–31 1/2" | 39 3/8" | — | 3 1/2" | — |
| Estonia low confidence | 6 5/16" | — | 10 5/8" | — | 6' 10 11/16" | 35 7/16" | 35 7/16"–35 7/16" | 39 3/8" | — | 4 5/16" | — |
| Finland high confidence | 7 1/2" | — | 9 13/16" | — | 6' 4 3/4" | 33 7/16" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | — |
| France medium confidence | 8 1/4" | 6 5/16" | 8 1/4" | — | 6' 2 13/16" | 27 9/16" | 31 1/2"–39 3/8" | 39 3/8" | — | 4 5/16" | 17' 2 11/16" |
| Germany (DIN 18065) | 7 7/8" | 5 1/2" | 9 1/16" | 3/16" | 6' 6 3/4" | 31 1/2" | 35 7/16"–43 5/16" | 35 7/16" | 39 3/8" | 4 5/16" | — |
| Greece high confidence | 7 1/16" | 5 1/8" | 9 13/16" | — | 7' 2 5/8" | 35 7/16" | 35 7/16"–39 3/8" | 39 3/8" | — | 5 7/8" | 11' 9 3/4" |
| Hungary high confidence | 7 7/8" | — | 10 1/4" | — | 6' 6 3/4" | 31 1/2" | 35 7/16"–39 3/8" | 37 3/8" | — | 4 3/4" | 9' 10 1/8" |
| Iceland high confidence | 7 1/16" | 4 3/4" | 9 7/16" | — | 6' 10 11/16" | 35 7/16" | 31 1/2"–35 7/16" | 35 7/16" | — | 3 1/2" | 10' 9 15/16" |
| Ireland high confidence | 8 11/16" | — | 8 11/16" | — | 6' 6 3/4" | 31 1/2" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | 11' 6 9/16" |
| Italy medium confidence | 6 7/8" | — | 11 13/16" | — | 6' 10 11/16" | 31 1/2" | 35 7/16"–39 3/8" | 39 3/8" | — | 3 15/16" | — |
| Latvia high confidence | 7 1/16" | 4 3/4" | 9 7/16" | — | — | 35 7/16" | 35 7/16"–39 3/8" | 43 5/16" | — | 4 3/4" | — |
| Lithuania high confidence | 7 7/8" | — | 9 13/16" | — | 6' 6 3/4" | 35 7/16" | 35 7/16"–39 3/8" | 35 7/16" | — | 4 3/4" | 10' 1/2" |
| Luxembourg medium confidence | 6 11/16" | — | 9 13/16" | — | 7' 2 5/8" | 47 1/4" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | — |
| Malta medium confidence | 8 11/16" | — | 8 11/16" | — | 6' 6 3/4" | 35 7/16" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | 25' 11 13/16" |
| Moldova high confidence | 5 7/8" | — | 9 13/16" | — | 6' 6 3/4" | 35 7/16" | 35 7/16"–39 3/8" | 47 1/4" | — | 3 15/16" | 8' 10 5/16" |
| Montenegro medium confidence | 7 1/16" | — | 11" | — | 7' 2 5/8" | 47 1/4" | 35 7/16"–39 3/8" | 43 5/16" | — | 3 15/16" | 7' 1 1/16" |
| Netherlands high confidence | 7 3/8" | — | 8 11/16" | — | 7' 6 9/16" | 31 1/2" | 31 1/2"–39 3/8" | 39 3/8" | — | 3 15/16" | 13' 1 1/2" |
| North Macedonia medium confidence | 7 1/16" | — | 11" | — | 6' 10 11/16" | 43 5/16" | 35 7/16"–39 3/8" | 39 3/8" | — | 3 15/16" | 10' 7 9/16" |
| Norway high confidence | 7 11/16" | — | 9 13/16" | — | 6' 6 3/4" | 31 1/2" | 27 9/16"–35 7/16" | 35 7/16" | — | 3 15/16" | 10' 9 15/16" |
| Poland high confidence | 7 1/2" | — | 9 13/16" | — | 6' 6 3/4" | 31 1/2" | 35 7/16"–39 3/8" | 35 7/16" | — | 4 3/4" | — |
| Portugal medium confidence | 7 5/8" | — | 9 13/16" | — | 7' 10 1/2" | 31 1/2" | 33 7/16"–35 7/16" | 43 5/16" | — | 3 9/16" | 7' 10 1/2" |
| Romania high confidence | 6 7/8" | — | 10 5/8" | — | 6' 6 3/4" | 37 3/8" | 35 7/16"–35 7/16" | 35 7/16" | — | 3 15/16" | — |
| Russia high confidence | 8 11/16" | 1 15/16" | 9 13/16" | — | 7' 2 5/8" | 41 5/16" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | 11' 6 9/16" |
| Serbia high confidence | 7 1/16" | — | 11" | — | 7' 2 5/8" | 47 1/4" | 35 7/16"–39 3/8" | 43 5/16" | — | 4 3/4" | 10' 1/2" |
| Slovakia high confidence | 7 7/8" | 5 7/8" | 8 1/4" | — | 6' 10 11/16" | 35 7/16" | 35 7/16"–47 1/4" | 39 3/8" | — | 4 3/4" | 10' 7 9/16" |
| Slovenia medium confidence | 7 1/2" | — | 9 13/16" | — | 6' 6 3/4" | 31 1/2" | 35 7/16"–39 3/8" | 39 3/8" | — | 4 3/4" | — |
| Spain high confidence | 7 7/8" | — | 8 11/16" | — | 6' 10 11/16" | 31 1/2" | 35 7/16"–43 5/16" | 35 7/16" | — | 3 15/16" | 10' 6" |
| Sweden high confidence | 7 7/8" | — | 9 13/16" | — | 6' 6 3/4" | 35 7/16" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | — |
| Switzerland medium confidence | 7 1/2" | — | 10 1/4" | — | 6' 10 11/16" | 35 7/16" | 33 7/16"–35 7/16" | 39 3/8" | — | 4 3/4" | — |
| Turkey high confidence | 7 1/16" | — | 10 5/8" | — | 6' 10 11/16" | 47 1/4" | 35 7/16"–39 3/8" | 43 5/16" | — | 3 15/16" | 9' 10 1/8" |
| UK (Part K) | 8 11/16" | 5 7/8" | 8 11/16" | — | 6' 6 3/4" | — | 35 7/16"–39 3/8" | 35 7/16" | 23 5/8" | 3 15/16" | — |
| Ukraine medium confidence | 7 7/8" | — | 7 1/16" | — | — | 41 5/16" | 35 7/16"–39 3/8" | 47 1/4" | — | — | — |
| Asia-Pacific | |||||||||||
| Afghanistan low confidence | 7 11/16" | — | 10" | — | 6' 8" | 36" | 34"–38" | 36" | — | 4" | 12' |
| Australia (NCC) | 7 1/2" | 4 1/2" | 9 7/16" | 3/8" | 6' 6 3/4" | — | 34 1/16"–43 5/16" | 39 3/8" | 39 3/8" | 4 15/16" | — |
| Bangladesh medium confidence | 9 1/16" | — | 13" | — | 7' 1" | 44 1/8" | 33 7/8"–37 13/16" | 41 5/16" | — | 3 15/16" | 12' |
| China high confidence | 6 7/8" | — | 10 1/4" | — | 7' 2 5/8" | 43 5/16" | 35 7/16"–39 3/8" | 47 1/4" | — | 4 5/16" | 10' 4" |
| India medium confidence | 7 1/2" | — | 9 13/16" | — | 7' 2 5/8" | 35 7/16" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | 7' 5 3/4" |
| Indonesia low confidence | 7 7/8" | — | 11" | — | 6' 6 3/4" | 47 1/4" | 34 1/16"–38" | 39 3/8" | — | 3 15/16" | — |
| Japan high confidence | 9 1/16" | — | 5 7/8" | — | 6' 10 11/16" | 29 1/2" | 35 7/16"–39 3/8" | 43 5/16" | — | 4 5/16" | 13' 1 1/2" |
| Malaysia high confidence | 7 1/16" | — | 10 1/16" | — | 6' 6 3/4" | — | 32 1/2"–35 7/16" | 39 3/8" | — | — | 13' 11 5/16" |
| Myanmar high confidence | 8" | 4" | 10" | — | 7' | 36" | 36"–39 3/8" | 36" | — | 4" | — |
| Nepal high confidence | 7 1/2" | — | 9 13/16" | — | 6' 6 3/4" | 35 7/16" | 35 7/16"–35 7/16" | 39 3/8" | — | — | — |
| Pakistan medium confidence | 7 1/16" | — | 9 1/16" | — | 6' 10 11/16" | 47 1/4" | 35 7/16"–39 3/8" | — | — | — | — |
| Philippines high confidence | 7 7/8" | — | 9 13/16" | — | 6' 6 3/4" | 29 1/2" | 31 1/2"–35 7/16" | 43 5/16" | — | — | 11' 9 3/4" |
| South Korea high confidence | 7 1/16" | — | 10 1/4" | — | 6' 10 11/16" | 47 1/4" | 33 7/16"–33 7/16" | 47 1/4" | — | 3 15/16" | 9' 10 1/8" |
| Thailand high confidence | 7 7/8" | — | 8 11/16" | — | 6' 2 13/16" | 31 1/2" | 35 7/16"–39 3/8" | — | — | — | 9' 10 1/8" |
| Uzbekistan medium confidence | 6 11/16" | 5 1/8" | 11" | — | — | 41 5/16" | 35 7/16"–39 3/8" | 35 7/16" | — | — | 10' 1/2" |
| Vietnam high confidence | 7 1/2" | 1 15/16" | 9 13/16" | — | 6' 6 3/4" | 27 9/16" | 35 7/16"–39 3/8" | 35 7/16" | — | 3 15/16" | — |
| Americas | |||||||||||
| Argentina high confidence | 7 1/16" | — | 9 1/16" | — | 6' 6 3/4" | 39 3/8" | 33 7/16"–39 3/8" | 33 7/16" | — | 4 3/4" | 12' 4 13/16" |
| Brazil medium confidence | 7 1/16" | 6 5/16" | 11" | — | 6' 10 11/16" | 47 1/4" | 27 9/16"–36 1/4" | 43 5/16" | — | 4 5/16" | 10' 6" |
| Canada (NBC) | 7 7/8" | 4 15/16" | 10 1/16" | 3/8" | 6' 4 3/4" | 33 7/8" | 34 1/16"–42 1/8" | 35 7/16" | 23 5/8" | 3 15/16" | 12' 1 11/16" |
| Colombia high confidence | 7 1/16" | 3 15/16" | 11" | — | 6' 6 3/4" | 29 1/2" | 27 9/16"–35 7/16" | — | — | — | 11' 5 13/16" |
| Mexico high confidence | 7 1/16" | 3 15/16" | 9 13/16" | — | — | 35 7/16" | 35 7/16"–39 3/8" | 35 7/16" | — | — | 8' 10 5/16" |
| Peru high confidence | 7 1/16" | — | 9 13/16" | — | 6' 10 11/16" | 35 7/16" | 33 7/16"–39 3/8" | 39 3/8" | — | 5 7/8" | 10' 1/2" |
| Venezuela medium confidence | 7 7/8" | 5 7/8" | 10 1/4" | — | — | 47 1/4" | 29 1/2"–35 7/16" | 35 7/16" | — | 5 7/8" | 7' 10 1/2" |
| Middle East | |||||||||||
| Iran medium confidence | 7 1/16" | 3 15/16" | 11" | — | 6' 8 11/16" | 43 5/16" | 33 7/16"–35 7/16" | 35 7/16" | — | 4 5/16" | 12' 1 11/16" |
| Iraq low confidence | 7 7/8" | — | 9 13/16" | — | — | — | 35 7/16"–39 3/8" | — | — | — | — |
| Saudi Arabia medium confidence | 7 7/8" | — | 9 13/16" | — | 6' 6 3/4" | 35 7/16" | 34 1/16"–38" | 42" | — | 3 15/16" | 12' |
| Yemen low confidence | 7 7/8" | — | 9 13/16" | — | 6' 6 3/4" | 35 7/16" | 34 1/16"–38" | 42" | — | 3 15/16" | 12' |
| Africa | |||||||||||
| Algeria low confidence | 6 5/16" | — | 12 5/8" | — | — | 31 1/2" | 35 7/16"–39 3/8" | 39 3/8" | — | 4 5/16" | — |
| Angola medium confidence | 7 5/8" | — | 9 13/16" | — | — | 31 1/2" | 35 7/16"–39 3/8" | — | — | — | — |
| DR Congo low confidence | 8 1/4" | 6 5/16" | 8 1/4" | — | 6' 2 13/16" | 27 9/16" | 35 7/16"–39 3/8" | 39 3/8" | — | 4 5/16" | — |
| Egypt high confidence | 6 11/16" | — | 10 5/8" | — | 6' 10 11/16" | 43 5/16" | 35 7/16"–47 1/4" | 35 7/16" | — | 5 7/8" | 7' 9 11/16" |
| Ethiopia low confidence | 7 7/8" | — | 9 13/16" | — | 7' 10 1/2" | — | 35 7/16"–39 3/8" | — | — | — | — |
| Ghana medium confidence | 7 1/2" | — | 9 13/16" | — | 6' 6 3/4" | 35 7/16" | 35 7/16"–39 3/8" | 39 3/8" | — | 3 15/16" | — |
| Kenya medium confidence | 7 1/2" | — | 9" | — | 6' 9" | 30" | 35 7/16"–39 3/8" | 33" | — | 5" | 10' |
| Morocco low confidence | 6 5/16" | — | 11" | — | — | 47 1/4" | 31 1/2"–39 3/8" | 35 7/16" | — | — | — |
| Mozambique medium confidence | 7 5/8" | — | 9 13/16" | — | — | 31 1/2" | 35 7/16"–39 3/8" | — | — | — | — |
| Nigeria high confidence | 7 1/16" | 3 15/16" | 11" | — | 6' 10 11/16" | 36" | 34"–38" | 43 5/16" | — | 5 7/8" | 9' 10 1/8" |
| South Africa medium confidence | 7 7/8" | — | 9 13/16" | — | 6' 10 11/16" | 29 1/2" | 33 7/16"–39 3/8" | 39 3/8" | — | 3 15/16" | 9' 10 1/8" |
| Sudan low confidence | 7 7/8" | — | 9 13/16" | — | — | — | 35 7/16"–39 3/8" | — | — | — | — |
| Tanzania low confidence | 7 1/2" | — | 9" | — | 6' 9" | 30" | 33"–39 3/8" | 33" | — | 5" | — |
| Uganda high confidence | 6 7/8" | — | 9 1/16" | — | 6' 10 11/16" | 35 7/16" | 33 1/16"–39 3/8" | 35 7/16" | — | 4 15/16" | 8' 7/16" |
IRC vs IBC at a glance
| Limit | IRC (residential) | IBC (commercial) |
|---|---|---|
| Max riser | 7¾″ | 7″ |
| Min tread/run | 10″ | 11″ |
| Min width | 36″ | 44″ |
| Guard height | 36″ | 42″ |
| Rise between landings | 12′-7″ | 12 ft |
IRC, IBC, OSHA and ADA explained
Swipe the table sideways to compare every code →
| Requirement | IRC 2021 | IBC 2021 | OSHA 1910.25 | ADA 2010 |
|---|---|---|---|---|
| Max riser | 7 11/16" | 7" | 9 1/2" | 7" |
| Min run (going) | 10" | 11" | 9 1/2" | 11" |
| Min headroom | 6' 8" | 6' 8" | 6' 8" | 6' 8" |
| Handrail height | 34"–38" | 34"–38" | 30"–38" | 34"–38" |
IRC — homes
The International Residential Code governs one- and two-family homes. It allows the most generous steps: a maximum 7¾″ riser and a minimum 10″ tread, with 6′8″ headroom, a 36″ minimum width, and a handrail once there are four or more risers (R311.7).
IBC — commercial buildings
The International Building Code is stricter because more people use the stairs: a 7″ riser, an 11″ tread, and a wider 44″ minimum (or 36″ when the occupant load is under 50). Guards are 42″ tall versus the IRC’s 36″ (1011, 1015).
OSHA — workplaces
OSHA 1910.25 covers fixed industrial stairs: risers up to 9½″, an angle band of 30–50°, and a 22″ minimum width. It is the most permissive on pitch.
ADA — accessibility
Where stairs are part of an accessible route, the ADA matches the IBC step size but prohibits open risers and requires handrails on both sides — and note that stairs can never be the accessible route on their own; a ramp or elevator must be provided.
Comfort vs code
Code limits are minimums for safety, not targets for comfort. A stair can pass code and still feel steep. Aim for the 7-11 rule — about a 7″ rise with an 11″ run — which satisfies both classic comfort formulas (2 × rise + run ≈ 24″–25″ and rise + run ≈ 17″–18″) and lands near a comfortable 32–33°.
Three accuracy clarifications
- The IBC “12-foot” rule. The maximum vertical rise between landings is 12 ft under the IBC and 12′-7″ under the IRC — close, but not the same number.
- A 7-11 stair is 32.5°, not 37°. The angle is atan(7 ÷ 11) = 32.5°. The “37°” figure you’ll find online comes from pairing a 7″ rise with a too-short run.
- “Going” varies by class of building. Minimum tread/going differs between residential and commercial codes (10″ vs 11″), so the same stair can pass one code and fail another — which is exactly why the calculator lets you switch jurisdictions.
Stair codes by country
Building outside the US? These pages lead with each country’s own riser, going, headroom, handrail and guard limits, cite the code edition and official source, and compare it to the IRC.
UK stair code Approved Document KCanada stair code NBC 2020Australia stair code NCC 2022Germany stair code DIN 18065:2020Ireland stair code Building Regulations 2014, Technical Guidance Document K (TGD K) "Stairways, Ladders, Ramps and Guards" (in effect from 1 Jan 2015; gives effect to S.I. No. 180/2014)the Netherlands stair code Besluit bouwwerken leefomgeving (Bbl) 2024 (nieuwbouw, woonfunctie), formerly Bouwbesluit 2012; NEN 3509 walkability guidanceSweden stair code Boverkets byggregler (BBR), BFS 2011:6 ändrad t.o.m. BFS 2014:3, Avsnitt 8 'Säkerhet vid användning' (8:232, 8:2321, 8:2322, 8:34); dimensional figures partly from SS 914221:2006 (Byggnadsutformning – Bostäder, invändiga mått). Note: 'Möjligheternas byggregler' (new function-based rules, BFS 2024) in force 1 Jul 2025 with transition to 30 Jun 2026; it removes all allmänna råd, so the numeric figures below increasingly rely on SS 914221.Norway stair code TEK17 §12-14 (Trapp) & §12-15 (Utforming av rekkverk), Byggteknisk forskrift (FOR-2017-06-19-840) + DiBK 'Veiledning om tekniske krav til byggverk' / preaksepterte ytelserSpain stair code CTE DB-SUA (Código Técnico de la Edificación, Documento Básico de Seguridad de Utilización y Accesibilidad)Japan stair code Building Standard Act Enforcement Order (建築基準法施行令), Art. 23 (stair/landing width, riser, tread), Art. 24 (landings), Art. 25 (handrails), Art. 126 (guards)South Korea stair code 주택건설기준 등에 관한 규정 (Housing Construction Standards Decree, Arts. 16 & 18) + 건축물의 피난·방화구조 등의 기준에 관한 규칙 제15조 (Building Act Enforcement Rules on Evacuation/Fire-Protection Structures, Art. 15)Mexico stair code Reglamento de Construcciones para el DF (RCDF) + NTC para el Proyecto Arquitectonico, Sec 4.3 Escaleras (dominant national reference; Mexico has no single federal building code)
Check your stairs against these limits
Stairs Calculator Enter one measurement — your total rise — and get a complete, code‑compliant stair layout with a 3D diagram, stringer cut list, and printable template. Free, instant, in inches or millimeters. Stair Stringer Calculator Get the exact stringer length, throat depth, recommended board size, and a step‑by‑step cut layout with framing‑square settings — then print a full‑scale template. Stair Rise and Run Calculator Turn one total‑rise measurement into equal risers and runs that meet code — with the comfort rules (2R+T and Rise+Run) checked for you.
Written by the Stairs Calc editorial team. Methodology and code references: see our methodology.
Built and maintained by builders, drafters and engineers who plan stairs for a living — every code limit is transcribed from the published standard and cited to its exact section.
Last reviewed 2026-06-20 against IRC 2021/2024
Stairs Calc gives accurate geometry and checks it against published building-code limits, but results are estimates for planning. Codes are adopted and amended locally and change over time. Always confirm dimensions against your local adopted code and a licensed professional before you build.