BTHL
Zepsa Industries, Inc.
Supplier of architectural woodwork: stairs, mantels, paneling, wine cellars, doors & more.
A Concrete Reality: Poured, formed and blocked.
Concrete is the most widely used building product in the world. Given the scale of this industry, it is not surprising that the APT Building Technology Heritage Library (BTHL) contains many listings for concrete products, construction techniques, equipment and designs.
The Heat is on: Our Romance With Fireplaces
The fireplace has a unique place in design history, an obsolete technology that has an enduring grasp on our warmth, comfort and well-being.
Stone: A Catalog History Using the APT Building Technology Heritage Library
Stone is one of the world’s most common and durable building material.
Building Technology Heritage Library: Heavenly Spaces
The richness and variety of architecture is revealed in religious architecture.
Building Technology Heritage Library: Architectural Sheet Metal
Ornamental metals were used in several forms, but stamped sheet metal was a popular material for architectural exteriors and interiors from the 1870s through the 1920s.
Building Technology Heritage Library: Builders’ Hardware
The Building Technology Heritage Library is an open a door to Hardware History.

Building Technology Heritage Library: Ornament
The APT Building Technology Heritage Library has a visual cornucopia of documents that tell the story or architectural ornament.