How much does a cubic foot of oak weigh?

Answer 1

Red Oak Green < 37 Dry 39.2 lbs/cu-ft

White Oak Green < 37 Dry 41.7

Green weight in air 80 and 70 percent moisture content
Dry weight in air 12 percent moisture content
Exact green weight is below my charts and numbers are approximate.

Answer 2

I'd go with 40 pounds.

Oak, of course, like any wood and most natural products will have a range of densities. The heart-wood of a tree might be denser than the edges. Years with lots of rain may produce a ring with different density than a drought year.

A reliable looking reference book gives this density:

Tipler, Paul A. Physics for Scientists and Engineers. 3rd Edition. "wood (oak), 0.6 - 0.9 × 103 kg/m3" 600 - 900 kg/m3
(oak)

This matches other wood density references I found that generally put wood in the 100-1000 kg/m3 and seems right because most wood floats and therfore must be less dense than water at 1000 kg/m3.

Assuming Tipler's mid-range point of 600 kg/m3, one cubic foot would weigh: 600(kg/m3) * .0283 (m3/ft3) = 17.0 (kg/ft3)

At the surface of the earth, 17 kg mass weighs about 37 lbs.

I'm sure it depends on how green or seasoned or rotten or whatever the wood is, but I would say go with about:

40 lbs