Steel Frame Conservation, H. P. Steel Window Restoration’s crew works overnight.

Steel Frame Conservation, H. P. Steel Window Restoration’s crew works overnight.

H. P. Steel Window Restoration’s crew works overnight to conserve steel frames of the clerestory windows. Working overnight was a way to lessen the impact on visitors.

H. P. Steel Window Restoration’s crew works overnight to conserve steel frames of the clerestory windows. Working overnight was a way to lessen the impact on visitors.