Pole Barn Building Materials

National Barn Company�s construction methods are in compliance with the standard industry tolerances as designed by the National Frame Building Association. Some changes can be made to comply with local building restrictions, if applicable. Engineered buildings with a PE stamped drawing are also available, if required. Our sales representatives can answer any of your questions.

Poles & Bottom Plate

Posts are solid sawn 5 x 5 or 6 x 6 depending on the height of the building.
Laminated Columns are used in some instances.
# 2 Southern Yellow Pine lumber is standard.
.40 CCA treatment is standard for Central and Mountain Division.
.60 CCA treatment is standard for Eastern and Northeast Division. (.60 is optional for Central and Mountain)
Post spacing is typically 10' centers (8' or 12' centers are optional).
8' centers are standard for Northeast Division.
Post depth is a minimum 3' deep (based on level ground).
Posts can be set deeper to meet some code restrictions, for additional cost.
Bottom Plate is a treated 2 x 6. This board can be used as a form for the concrete slab.

Top Plate

Top Plate supports the trusses and is anchored to every post.
Double 2 x 6 is the minimum size used for Central and Eastern Division.
Double 2 x 8 is minimum size used for Mountain and Northeast Division.
2 x 8s, 2 x 10s, or 2 x 12s are also used, based on the width of the building.
LVL lumber is used for large spans or wide openings.
# 2 Southern Yellow Pine lumber is standard.

Wall Girts

2 x 4s spaced 24� apart for metal attachment.
2 x 6s are used in some instances.
# 2 Southern Yellow Pine lumber is standard.

Factory Engineered Trusses

Trusses are typically constructed of 2 x 6 rafter and ceiling joist with 2 x 4 braces, and are engineered for the location and the purpose that they are being used.
Engineered Trusses will typically include # 2 SYP lumber for the top and bottom chord, and some #3 SYP may be used for bracing.
Standard Truss spacing is 5� centers, except Northeast Division which is 4' centers.
Alternate truss spacing can be 2', 4',5' or 6' centers, based posts spacing and use of truss.
Standard roof pitch is 4/12, except Central Division which is 3/12.
Alternate roof pitch can be 512, 6/12, 7/12 or 8/12 (steeper pitches are more expensive).