Reversing Roof Sag on Bank Barns

Older timber frame bank barns are among the strongest and most enduring of wooden structures, and it takes many years of neglect to cause problems. However, on some bank barns, the roof may sag over time as moisture rots the bottom end of the bay doorposts. As the posts rot on the bottom, they grow shorter, causing more and more sag. Rainwater funnels to the sag in greater amounts, making gutters inefficient. Water soaks into the bank and then into the basement of the barn. The freezing and thawing cycle breaks the stones out, resulting in eventual collapse.


BCBB can address these problems. Note that this barn had sagged so badly over many years, that the old barn siding was installed years ago with the sag built into it. BCBB jacked up the doorpost and eliminated much of the problem. Some sag still exists, but this minor repair was enough to enable the gutters to do their job.

Upper post and door sill. Siding fits sag from long ago.

Post rotted on bottom despite sitting on old concrete pad.

Before: Tie beams bends down as post sags.

After: Tie beam made level as post was raised to original.

Sag improved, but water and rot problems dramatically improved.