Assemble Multi-Ply Perimeter Beams

What happens here

Select three pieces of 2x12 lumber for each perimeter beam. Prior to assembly, apply a coat of black stain or paint to all sides of the individual lumber pieces for weather protection and aesthetic finish. To achieve the desired width and allow for drainage and air circulation, place 1/2-inch composite spacers between each ply of lumber. Position the spacers at regular intervals along the length of the boards. Secure the plies and spacers together using GRK screws, ensuring the screws penetrate through all layers for a solid, unified beam. The assembled beams will be approximately 4.5 inches wide, fitting securely into the Skylift brackets designed for a 5.5-inch opening, allowing for the added 1/2-inch spacers. This process is repeated for all perimeter beams of the pergola structure.

Goal: Construct robust perimeter beams from multiple plies of lumber, incorporating composite spacers between plies for added width, air circulation, and drainage.