Concrete form size guide
Read the height, length, and quantity correctly.
A little notation can cause an expensive mistake. Here is exactly what the listed sizes and quantities mean on Ohio Metal Forms.
Updated September 5, 2026
Read height first, length second
A label such as 6" × 10' means the piece is 6 inches high and 10 feet long. Choose the height required for the concrete edge, then count how many individual sections the run needs.
Corner labels show the height of the Ohio Metal Forms straight section they are made to fit. A 6-inch corner should be ordered with 6-inch straight forms.
Compare the five standard steel-form heights
Straight and flexible sections are available in 4-, 6-, 8-, 10- and 12-inch heights. Every section below is 10 feet long and sold by the piece. Open the selected size to check its current price.
On a small screen, scroll horizontally to review every column.
| Required form height | Straight steel section | Flexible steel section |
|---|---|---|
| 4 inches | 4-inch × 10-foot straight form | 4-inch × 10-foot flexible form |
| 6 inches | 6-inch × 10-foot straight form | 6-inch × 10-foot flexible form |
| 8 inches | 8-inch × 10-foot straight form | 8-inch × 10-foot flexible form |
| 10 inches | 10-inch × 10-foot straight form | 10-inch × 10-foot flexible form |
| 12 inches | 12-inch × 10-foot straight form | 12-inch × 10-foot flexible form |
Choose from the approved concrete edge detail. A sidewalk, driveway or pad name does not establish slab thickness, and catalog height does not specify reinforcement, load capacity or a safe curve limit. The form-height decision guide explains what to verify before ordering.
Quantity always means pieces
Quantity 4 on a 6" × 10' straight form adds four individual 10 ft sections. It does not add four feet or 40 feet as one continuous form.
Know what each product contributes
On a small screen, scroll horizontally to review every column.
| Product | Listed length | Use | Matching rule |
|---|---|---|---|
| Straight form | 10 ft | Straight run | Choose required edge height |
| Flexible form | 10 ft | Curved run | Choose required edge height; call about tight radiuses |
| Filler | 5 ft | Odd-length adjustment | Match the straight-form height |
| Corner | One corner | 90-degree turn | Match the straight-form height and connection direction |
Separate the order by height
If one job uses 4-inch forms and another part uses 6-inch forms, calculate each group separately. Do the same for straight and curved footage. This keeps the quantity list easy to review and helps prevent mismatched accessories.
Match the connection as well as the height
The OMF 90-degree corner fits the female end of a matching-height OMF straight section. Inside and outside describe the plan turn; the catalog does not list separate inside/outside corner variants. The five-foot filler slides over the matching straight form. Its listed length does not mean five feet of independent coverage: confirm the overlap and direction.
Hardware is not automatically included
Each quantity adds only the listed form piece. Pins, stakes, and other jobsite hardware are not automatically added. Do not assume parts from another forming system will fit.
Before you pay
- Confirm the required concrete edge height.
- Separate straight footage from curved footage.
- Count every 90-degree corner.
- Identify odd-length adjustments.
- Verify every quantity is a piece count.
- Call before mixing brands or forming systems.
Next step
Estimate the section count.
Use the quantity planner as a starting point, then let us check any unusual layout.