Layup Load Values

The loads presented in the tables below are based on both stress and deflection, whichever controls, using the design value listed. Allowable loads controlled by stress are increased 15% for a two month load duration. Allowable loads are controlled by deflection are based on applicable 1/180 or 1/240 span deflection limitations.

These values are to be used for roofs only. Contact Unit Structures for assistance on floor applications.

Pitched roofs should be designed using the converted loads and the converted spans.

These values are based on a maximum in-use moisture content of less than 15%. In environments exceeding 15% moisture content, reduce allowable loads 20%.  

No. 1 Grade
PSF @ L/180

Span (ft.)

Simple Span

Random Layup

2-Span

Comb.
6.0 73 96 135 104
6.5 58 75 115 82
7.0 46 60 99 65
7.5 38 49 86 54
8.0 31 40 75 44
8.5   33 62 37
9.0     52 31
9.5     45  
10.0     38  

No. 1 Grade
PSF @ L/240

Span (ft.)

Simple Span

Random Layup

2-Span

Comb.
6.0 55 71 133 78
6.5 43 56 104 62
7.0 34 45 84 49
7.5   37 68 40
8.0   30 56 33
8.5     47  
9.0     40  
9.5     33  

No. 2 Grade
PSF @ L/180

Span (ft.)

Simple Span

Random Layup

2-Span

Comb.
6.0 65 84 110 92
6.5 51 67 93 73
7.0 41 54 81 58
7.5 33 43 70 48
8.0   36 62 39
8.5   30 55 33
9.0     47  
9.5     40  
10.0     34  

No. 2 Grade
PSF @ L/240

Span (ft.)

Simple Span

Random Layup

2-Span

Comb.
6.0 49 63 110 70
6.5 39 50 92 55
7.0 31 40 74 44
7.5   33 61 35
8.0     49  
8.5     41  
9.0     35  
9.5     30