Project guides
How to measure, what to watch for and how much to buy, explained with worked examples.
Concrete
Concrete calculator →- Concrete Slab Thickness Guide: Patio, Driveway, Shed, Garage
How thick to pour a concrete patio, driveway, shed pad or garage floor, what each extra inch costs in concrete, and what goes under the slab.
- How Many Bags of Concrete Do You Need per Fence Post?
Bags of concrete per fence post by hole size and depth, for 4x4 and 6x6 posts, with the formula, a worked example for a whole fence and setting tips.
Gravel and sand
Gravel calculator →- How Much Does a Cubic Yard of Gravel Weigh?
A cubic yard of gravel weighs about 1.3 to 1.5 tons. See weights for crushed stone, crusher run, pea gravel, sand and topsoil, and convert yards to tons.
- How Many Deck Boards Do I Need? Count by Rows, Not Area
Count deck boards row by row: rows from the board width plus gap, boards per row from the board length. Includes a chart of the best board length for each deck size.
Roofing
Roofing calculator →- Roof Pitch Multiplier Chart: Turn a Footprint into Roof Area
Pitch multipliers from 1/12 to 18/12 with roof angles and hip and valley factors. Multiply the footprint by the multiplier to get the real roof area.
Stairs
Stair calculator →- Stair Rise and Run: Code Limits and Comfortable Dimensions
The IRC allows risers up to 7 3/4 in and treads down to 10 in, but comfortable stairs sit nearer 7 in by 11 in. The rules of thumb, with a chart and an example.
- Tile Waste Factor by Layout: Straight, Diagonal, Herringbone
How much extra tile to buy for straight, offset, diagonal and herringbone layouts, why small rooms waste more, and how waste changes the box count.
- How to Measure an L-Shaped Room (and Other Odd Shapes)
Measure the square footage of L-shaped and irregular rooms by splitting them into rectangles, with diagrams, formulas for odd shapes and a worked example.
Flooring
Flooring calculator →- How Many Boxes of Vinyl Plank Flooring Do I Need?
Work out boxes of vinyl plank flooring from your square footage and the coverage on the box, with a chart for common box sizes and a worked example.
Drywall
Drywall calculator →- How Many Sheets of Drywall for a 12x12 Room?
A 12x12 room with 8 ft walls takes 12 sheets of 4x8 drywall for the walls and 5 for the ceiling. See counts for 9 and 10 ft walls and 4x12 sheets.
Paint
Paint calculator →- How Much Paint for a 12x12 Room? Coverage Chart by Room Size
A 12x12 room with 8 ft walls takes about 2 gallons of paint for two coats. See the coverage chart for 10x10 to 20x20 rooms, with and without the ceiling.