Calculators for floors, each inside a guide that shows the formula with a worked example. Start with the square footage calculator (length times width, with L-shaped rooms split into rectangles), then order materials: boxes of laminate, vinyl plank, or hardwood with the flooring calculator, tiles and boxes with the tile calculator (10 percent extra for straight layouts, 15 percent or more for diagonal ones), pounds and bags of grout with the grout calculator, linear feet and square yards off a 12 or 15 ft roll with the carpet calculator, and 4 x 8 sheets of plywood or OSB for a subfloor with the plywood calculator.
Enter the room size, roll width, and trim to get the linear feet, square yards, and square feet of carpet to order, plus the pad area: a 14 x 11 ft room takes one 14.5 ft piece of 12 ft wide carpet, 19.33 sq yd. Includes a room-size chart for 12 and 15 ft rolls, where seams go, and how much extra to buy.
Enter the area, tile size, tile thickness, and joint width to get pounds and whole bags of grout: 100 sq ft of 12 x 12 in tile with 1/8 in joints takes about 6.5 lb, or 7.2 lb with 10% extra. Includes a grout-per-100-sq-ft chart, a comparison with makers’ bag charts, and sanded vs unsanded joint ranges.
Divide the area you are covering by 32 sq ft per 4 x 8 sheet and add about 10 percent for cuts: a 16 x 12 ft floor needs 7 sheets of plywood or OSB. Includes measuring steps for floors, walls, and roofs and a sheet chart by size.
Multiply length by width in feet. For irregular rooms, split the space into rectangles, find each area, and add them up. A 12 x 10 ft room is 120 sq ft.
Multiply length by width, add 5 to 15 percent for cuts depending on the layout, and divide by the square feet printed on the box. A 14 x 12 ft room needs 10 boxes of 20 sq ft flooring with 10 percent extra.
Divide the area by the square footage of one tile, add 10 percent for straight layouts or 15 percent or more for diagonal and patterned layouts, and round up to full boxes. An 8 x 10 ft floor needs 88 tiles of 12 x 12 with 10 percent extra.