How much flooring do I need for a 18x18 room?

Buy about 356 sq ft: the 324 sq ft floor plus 10% for cuts and waste. With boxes that cover 20 sq ft, that's 18 boxes. Diagonal or herringbone layouts need 15–20% extra instead.

How much paint do I need for a 18x18 room?

With 8 ft ceilings, one door and one window, the walls are about 540 sq ft. Two coats at 350 sq ft per gallon is 3.1 gallons, so buy 4. Painting the ceiling as well brings it to 4.9 gallons.

How many square meters is 18 by 18 feet?

30.1 m². The room is 5.49 m by 5.49 m.

How many sheets of drywall for a 18x18 room?

About 30 sheets of 4x8 drywall for the walls and ceiling with 8 ft walls, one door and one window, including 10% waste.

Room sizes

How Many Square Feet Is a 18x18 Room?

A 18x18 room is 324 square feet (30.1 m²). Flooring with waste, paint, drywall and baseboard for a 18x18 room.

Updated October 12, 2026 · FloorFigures

Short answer

A 18x18 room is 324 square feet (18 × 18), or 30.1 m² and 36 square yards. Its perimeter is 72 ft. Flooring with 10% waste comes to about 356 sq ft.

Drawn to scale. Each grid square is 1 ft × 1 ft.

Materials for a 18x18 room

Estimates for a plain rectangular room with 8 ft ceilings, one door and one window. Adjust for your own room with the flooring, paint and drywall calculators.

Item	Quantity	Assumes
Floor area	324 sq ft	Wall to wall
Flooring to buy	356 sq ft (18 boxes)	10% waste, 20 sq ft boxes
Carpet	49.3 sq yd	12 ft roll, 1 seam
Wall area	540 sq ft	8 ft walls, less a door and a window
Paint, walls	3.1 gal (buy 4)	2 coats, 350 sq ft per gallon
Paint, walls and ceiling	4.9 gal	2 coats
Drywall	30 sheets	4x8 sheets, walls and ceiling, 10% waste
Baseboard	69 ft	Perimeter less a 3 ft door

What a 18x18 room is used for

Rooms this size are usually living rooms, family rooms, large primary suites or open kitchens. A queen bed (60" × 80") takes up about 33 sq ft, or 10% of the floor.

18x18 in other units

Unit	Value
Square feet	324
Square meters	30.1
Square yards	36
Square inches	46,656
Acres	0.0074
Dimensions in meters	5.49 × 5.49 m

Rooms close to 18x18

Room	Square feet	Square meters
15x18	270	25.1
14x20	280	26
12x24	288	26.8
16x18	288	26.8
15x20	300	27.9
16x20	320	29.7
18x20	360	33.4
16x24	384	35.7

Room not a simple rectangle? Use the square footage calculator for L-shapes and angled walls, or split it into rectangles.

Questions

How many square feet is a 18x18 room?: A 18 by 18 foot room is 324 square feet: 18 × 18 = 324. That's 30.1 square meters or 36 square yards.
How much flooring do I need for a 18x18 room?: Buy about 356 sq ft: the 324 sq ft floor plus 10% for cuts and waste. With boxes that cover 20 sq ft, that's 18 boxes. Diagonal or herringbone layouts need 15–20% extra instead.
How much paint do I need for a 18x18 room?: With 8 ft ceilings, one door and one window, the walls are about 540 sq ft. Two coats at 350 sq ft per gallon is 3.1 gallons, so buy 4. Painting the ceiling as well brings it to 4.9 gallons.
How many square meters is 18 by 18 feet?: 30.1 m². The room is 5.49 m by 5.49 m.
How many sheets of drywall for a 18x18 room?: About 30 sheets of 4x8 drywall for the walls and ceiling with 8 ft walls, one door and one window, including 10% waste.