The International Institute of Building Enclosure Consultants (IIBEC) retired the term envelope in favor of enclosure to describe a building’s array of exterior surfaces.

Sure, enclosure could be considered a more intuitive way to describe a building’s exterior and primary function. And at the end of the day, it’s in IIBEC’s name.

They’ve encouraged others to join them in this semantic switch. But we’re sticking with envelope for a few reasons:

Envelope encompasses a building’s outside walls, roofs, and even terraces and plazas in a single term—one with important implications.

• It’s more poetic, with connotations of an essential interface or, for that matter, conventional limitations to be tested. Nobody “pushes the enclosure.”
• Envelope’s root, envelop, connotes a more sympathetic relationship to the building, a membrane that mediates between indoor and outdoor space.
• Sidewalk vaults—one of our areas of expertise—challenge the notion of limited, stand-alone enclosure. A building envelope is a continuum, tied into a larger, urban fabric.

So what’s in a name? In this case, a lively debate more than a definitive rebranding.

When it comes to describing the exterior surfaces of a building and the focus of our business, we’ll take the envelope . . . please.