Though visitors to 100 Terrace St. in Roxbury could be forgiven for not knowing that the Building Materials Resource Center and the Boston Building Materials Co-op are different entities, the two soon will be one and the same, under the name Boston Building Resources.

“We are making this change to make it easier to explain who we are and what we do,” said Matthew St. Onge, Boston Building Resources executive director. “The public has often seen us as a single organization because our names were so similar, and because the work of both organizations often overlaps."

The BMRC sells new building materials; the co-op accepts new and "gently used" materials to be sold at deep-discount retail for income-qualified customers.

To call attention to the merger, the new a href="http://www.bostonbuildingresources.com/" target="_blank">BBR will host a series of demonstrations on April 30 from 11 to 3: how to build a raised gardening bed, blowing in cellulose insulation, and home composting, among others.