Type B Metal Deck Span Tables, 22 to 16 Gauge
Our catalog publishes 1.5" Type B span tables for 22, 20, 18 and 16 gauge: allowable downward and upward loads for single, double and triple spans from 5'-0" to 10'-0", L/240 deflection loads and construction spans. At 6'-0" triple span, for example, allowable downward load runs from 119 psf at 22 gauge to 273 psf at 16 gauge. Ask us for the full tables.
Reading the table
Values below are ASD allowable uniform superimposed downward loads in psf for triple-span (three or more spans) conditions, with span measured center to center of supports. They do not include web crippling or shear, and deflection may control. Check the L/240 table before choosing a gauge.
What else the full tables cover
- Single and double spans, which carry less than triple at most spans.
- Upward (wind uplift) loads for each condition.
- Construction spans: up to 10'-02" for 22 gauge and 23'-08" for 16 gauge on multiple spans.
- The same values for vented Type B.
Use them, then verify
These are catalog values for preliminary selection. The engineer of record sets the final gauge and span for Florida wind and roof loads. Send your framing plan for a takeoff and quote.
1.5" Type B ASD uniform downward load, triple span, psf (catalog)
| Gauge | 5'-0" | 6'-0" | 7'-0" | 8'-0" | 10'-0" |
|---|---|---|---|---|---|
| 22 | 172 | 119 | 88 | 67 | 43 |
| 20 | 222 | 154 | 113 | 87 | 55 |
| 18 | 311 | 216 | 159 | 122 | 78 |
| 16 | 394 | 273 | 201 | 154 | 98 |
Related Questions
Which gauge of Type B is most common?
It depends on support spacing and wind exposure, so there is no single answer. Lighter gauges suit closely spaced joists or purlins; heavier gauges allow wider spacing or handle higher uplift. Compare deck cost against fewer supports, then let the engineer of record confirm. We supply all four gauges.
Can I interpolate between spans in the table?
The catalog lists spans in 6-inch steps from 5'-0" to 10'-0". Using the value for the next longer span is conservative. Straight-line interpolation is common in practice but not exact, since load drops with the square of span. Spans beyond 10'-0" need the engineer's own calculation.