Wire mesh calculator for concrete slabs
Enter the slab, the mesh product and the lap between pieces to see how many sheets or rolls to buy. Whether a slab needs mesh, and which style, comes from your plans.
Enter your measurements
- Layout
- 5 strips × 19.7 ft = 98.3 ft of roll (0.66 of a roll)
- Area to cover
- 387 sq ft
- Weight of the mesh bought
- 150 lb
Area inside the edge distance: 387 sq ft
5 strips × 19.7 ft = 98.3 ft of roll (0.66 of a roll) ÷ 150 ft per roll = 1 piece
× 149.81 lb each = 150 lb
- Mesh does its job only if it ends up inside the concrete. Set it on chairs or blocks at the height your plans show — pulling it up with a rake during the pour is unreliable.
- Flatten rolled mesh before you place it; it wants to curl back into a roll.
Quick answers for common sizes
| Example | Answer |
|---|---|
| How much wire mesh for a slab | One 5 × 150 ft roll, or 3 sheets of 8 × 20 ft (8 in laps) |
Every mesh product for the slab above
| Mesh product | Sheets or rolls | Weight of the mesh bought |
|---|---|---|
| Roll, 5 × 150 ft | 1 piece | 150 lb |
| Sheet, 5 × 10 ft | 15 pieces | 150 lb |
| Sheet, 8 × 12½ ft | 6 pieces | 118 lb |
| Sheet, 8 × 15 ft | 6 pieces | 141 lb |
| Sheet, 8 × 20 ft | 3 pieces | 94 lb |
Welded wire mesh (welded wire reinforcement, or WWR) is a grid of steel wires welded at every crossing. The common slab styles are 6×6 W1.4/W1.4 and 6×6 W2.9/W2.9: wires 6 in apart both ways, with W1.4 (about 10 gauge) or W2.9 (about 6 gauge) wire. Whether your slab needs mesh, rebar, fibers or nothing — and which style — comes from your plans or local practice.
Standard sizes and weights
| Product | Covers (before laps) | 6×6 W1.4/W1.4 | 6×6 W2.9/W2.9 |
|---|---|---|---|
| Roll, 5 × 150 ft | 750 sq ft | 149.81 lb | 310.31 lb |
| Sheet, 5 × 10 ft | 50 sq ft | 9.99 lb | 20.69 lb |
| Sheet, 8 × 12½ ft | 100 sq ft | 19.62 lb | 40.64 lb |
| Sheet, 8 × 15 ft | 120 sq ft | 23.54 lb | 48.76 lb |
| Sheet, 8 × 20 ft | 160 sq ft | 31.39 lb | 65.02 lb |
How the count works
For plain welded wire such as 6×6 mesh, ACI 439.5R gives a lap of one mesh square plus 2 in — 8 in for 6×6 — as reported by the American Society of Concrete Contractors; that is the default here unless your plans say otherwise.
Pieces overlap where they meet, so each one covers a little less than its size. The calculator tries both orientations of a sheet and picks the one that needs fewer; for rolls, it lays strips the full length of the slab across its width. A worked example is on how much wire mesh for a slab.
sheets = ceil((length − lap) ÷ (sheet length − lap)) × ceil((width − lap) ÷ (sheet width − lap)) roll strips = ceil((width − lap) ÷ (5 ft − lap)); rolls = strips × slab length ÷ 150 ft
Sheets or rolls?
- Sheets lie flat, are easy to handle and cut, and suit small slabs and walks.
- Rolls are cheaper per square foot for big slabs, but the mesh springs back toward a curl and has to be flattened and weighted before the pour.
- Heavier W2.9 mesh comes in the same sizes and weighs about twice as much.
What you’ll need
- Rebar chairsBudget price
Hold rebar or mesh off the ground so it ends up inside the concrete, not under it. Match the chair height to where your plans place the steel.
See options on Amazon (opens in a new tab) - Rebar tie wire and twisterBudget price
Ties bars together where they cross so the grid stays put while you pour.
See options on Amazon (opens in a new tab) - Nitrile-coated work glovesBudget price
Wet concrete and mortar are caustic. Keep the cement off your skin with waterproof gloves, and wash off any that gets in.
See options on Amazon (opens in a new tab)
As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links — they cost you nothing extra and help keep these calculators free.
Frequently asked questions
How many sheets of wire mesh do I need for a 10×10 slab?
With 5 × 10 ft sheets and an 8 in lap, a 10 × 10 slab with 2 in edges takes 3 sheets; one 8 × 12½ ft sheet doesn’t quite cover it in both directions, so you would need 2.
What does 6×6 W1.4/W1.4 mean?
Wires 6 in apart in both directions, each with a cross-section of 0.014 sq in (W1.4). W2.9 wires have 0.029 sq in — about twice the steel.
Is wire mesh the same as rebar?
No. Mesh is lighter, welded at every crossing and comes in sheets or rolls; rebar is individual heavier bars tied into a grid. Which a slab needs is a design decision — see the rebar calculator for bar counts.
Related guides
Sources
- Insteel — Welded wire reinforcement reference information (opens in a new tab) — 6×6 W1.4/W1.4 in 5×150 ft rolls (149.81 lb) and 8×20, 8×15, 8×12.5 and 5×10 ft sheets; 6×6 W2.9/W2.9 in 5×150 rolls and the same sheets.
- American Society of Concrete Contractors — WWR lap splice requirements (hotline Q&A, citing ACI 439.5R-18 §6.4) (opens in a new tab) — Plain-wire welded wire lap splice: one square plus 2 in — 8 in for 6×6 mesh.
- Insteel — Welded wire reinforcement (opens in a new tab) — Standard WWR conforms to ASTM A1064; wire sizes W1.4 to W/D4.