Room Sizes and Clearances (2026): Code Minimums, NKBA Numbers and the Conventions Contractors Plan To

The IRC exempts kitchens from the 70 sq ft room rule and says nothing about aisles, islands or the work triangle. What it fixes is electrical and exhaust. Everything a kitchen is planned to comes from NKBA's guidelines, and every one of them is a recommendation, not a requirement. Aisles are measured between counter fronts, tall cabinets and appliances, not from the wall.

The island and its aisles

The work triangle

The same 15 x 12 kitchen in Quick Clamp twice: a 3 x 7 island dropped at its real size, and the work triangle between the sink in the island, the range and the refrigerator. The aisle and triangle figures were added for this guide; the sketch gives the room and the fixtures, you read the gaps. Recreated from the app with demo data.

A centered 36 in deep island in a 12 ft room leaves 46 1/2 in on the working side and 36 in behind. That passes as long as nobody cooks from the back side. Make the island 30 in deep or move it 3 in toward the counter and both aisles clear 42.

Three sets of numbers govern a full bath and a primary bath alike. The IRC's plumbing figure sets the floor. The Uniform Plumbing Code, which California and other UPC states use, asks for 24 in in front of a toilet instead of 21. NKBA sits above both. A primary bath gets no separate standard; it just has more fixtures to clear.

To code: 15 in, 36 in vanity

To NKBA: 18 in, 30 in vanity

A 5 x 8 bath in Quick Clamp laid out twice: to code, with the toilet 15 in from the tub and a 36 in vanity, and to NKBA, with 18 in each side of the toilet and a 30 in vanity. Both leave 30 in in front. The dimension notes were added for this guide. Recreated from the app with demo data.

In a 5 x 8 bath the width does the work. A 30 in deep tub and a 30 in deep toilet leave 30 in in front, which clears code and meets NKBA at once. The toilet is the trade: 15 in each side keeps a 36 in vanity; NKBA's 18 in on both sides leaves 30. Either way the lav centerline lands at 15 or 16 1/2 in from the wall, under NKBA's 20.

These are code, and the headline numbers are the same in every edition since 2018. The one change worth knowing for remodels is new in 2024: a habitable basement or attic created in an existing building may have a 6 ft 8 in ceiling, 6 ft 4 in in its baths and laundry, where new construction needs 7 ft.

Bedroom, egress and hall

A stair to code

A 10 x 12 bedroom with its egress window, a 32 in door and a 36 in hall beside it, and a stair sketched in elevation: 13 risers at 7 1/2 in, 10 in treads, the handrail and the 6 ft 8 in headroom line. Code minimums were added as notes. Recreated from the app with demo data.

The egress figures work together: 20 by 24 in is only 3.3 sq ft, so a window has to beat 5.7 sq ft on its own. Replacing a window in an existing frame may use the largest standard size that fits, and a new sleeping room made in an existing basement may keep an existing window of 4 sq ft and 22 in of height (R319.7.1).

Deck numbers are the guard and stair sections plus R507 for framing. The American Wood Council's DCA 6 is the prescriptive guide inspectors accept; its current edition is still the 2015 IRC version (file dated April 2018), so check your state's R507 where the two differ.

Deck zones and guards

A 12 x 16 deck in Quick Clamp: the guard on the three open sides, a 36 in stair, a 48 in table with 4 ft clear all around, and the grill 24 in off the house. The clearance notes were added for this guide. Recreated from the app with demo data.

Dining, living, bedrooms, closets, laundry and mudrooms have code minimums only for room size, ceilings and egress. Their planning numbers come from two anthropometric references, Panero and Zelnik's Human Dimension and Interior Space (1979) and Neufert's Architects' Data, and from makers and trade carpenters. They are firmer than they look: most trace to the same measured human body. Where sources disagree, both are given.

Dining clearances

Closet rods and shelf

A 12 x 14 dining room with a 36 x 72 table, 24 in a seat, 36 in to sit and the walk-behind distance; and a 6 ft reach-in closet drawn in elevation with the shelf at 84 in, double hang at 42 and 84, long hang at 66, 24 in deep. Convention figures added for this guide. Recreated from the app with demo data.

The ADA does not cover private homes, and the Fair Housing Act reaches only covered multifamily buildings. A remodeler who plans for a wheelchair or for aging in place is borrowing by choice, and the two sources differ. A117.1-2017 raised its numbers for new buildings; the Fair Housing manual and A117.1's existing-building figures keep the older ones, and NKBA's access column cites the 2009 edition.

A bath that turns a chair

The 5 x 8 bath planned for a wheelchair: a curbless 60 x 36 shower, a 60 in turning circle, 30 x 48 in clear at the toilet and a wall-hung lavatory with 27 in of knee room. The accessibility figures were added for this guide. Recreated from the app with demo data.

Measure the walls on the sketch pad, set the shape, and drop the island, the toilet or the tub at its real size. The drawing gives you the room and the fixture; this table gives you the gap each one needs. Where the number fails code, the layout changes. Where it fails only NKBA, it is a conversation with the homeowner, and the proposal should say which it was.

The sketch does not check these rules for you. It measures. Keep this page open beside it, cite the section your state is on, and never write 'meets code' on a proposal; the inspector decides that.

Every number above comes from one of three places. Code is the floor: the International Residential Code (IRC) as your state adopted it, and the inspector's basis. Standards are what a well-planned room has: NKBA for kitchens and baths, A117.1 and the Fair Housing manual for accessibility. Conventions are how designers and makers size the rest: dining, bedrooms, closets, laundry. Know which kind you are quoting. The 2024 IRC kept every value in this guide but moved the section numbers, so a Columbus contractor on the 2018 code and a Sacramento contractor on the 2024 code cite different sections for the same 7 ft ceiling.

As of the April 2026 adoption chart, California, Georgia, Iowa, Mississippi, New York and North Dakota were on the 2024 IRC statewide, with New Jersey joining in August 2026. Florida and Massachusetts were on 2021. Ohio is on 2018. Texas sets the 2012 IRC as a statutory floor and lets cities amend forward. Check your city before you quote a section.