# Glulam MBF

So, in another post we looked at `board feet’ (BF), or `board foot measure’ (BFM).  Now we’ll look at BF for structural glued laminated timber (glulam), and MBF, or MBFM.

From the earlier post, amount of lumber is often described in terms of `board feet’.  One board foot is `a board 1 inch thick, 12 inches wide, and 1 foot long’. Or equivalent. And the dimensions are nominal. A 1 x 12 that is 2 feet long has 2 board feet of lumber. A 2 x 6 that is one foot long has 1 BF. And so on. A 1 x 6 that is 2 feet long has 1 BF. Two 2 x 6’s side-by-side have 1 BF per foot of length. Two 2 x 6’s stacked on top of one another, 10 feet long, have 10 BF …

Cost of lumber is also often in terms of … per board foot, or per 1000’s of board feet (MBF).

….

Glulam is made up of laminations, the laminations of which are most often described in `nominal’ terms. For example, a Douglas fir glulam beam that is 5-1/8 in. x 12 in. x 16 feet long is made up of 8 (eight) 2 x 6 laminations, wide faces laminated (glued) together, each 2 x 6 (nominal) being 1-1/2 x 5-1/2 (actual), all 16 feet long. A `stack’ of eight 2 x 6’s. So, 8 x 1.5 = 12 … the depth of the glulam, and the width, 5-1/2, gets planed down to 5-1/8. How many board feet of lumber are in this beam? We look at the input lams. Each lam is 2 x 6, having 1 board foot per foot … there are 8 of them, and they are each 16 feet long …

Each glulam has … [ (2 x 6) / 12 ] x 8 x 16 … 128 BF.

10 of these beams … 1,280 BF.

100 of these beams … 12,800 BF … or 12.8 MBF.

Now go find the price of Douglas fir laminating stock, per MBF.

It will depend on the grade of laminating stock, and several grades go into a typical glulam beam.