View Full Version : Lintel Needed Above Glass Block?

Jeff Spencer
06-05-2008, 06:41 AM
In the last 2 days, I've inspected 2 houses in which glass block windows are installed in brick veneer walls. Lintels were not installed above any of the windows.

I have not had time to search to determine if glass block is rated to support loads imposed by brick veneer installed above. I usually see lintels in this type of installation, and was wondering if they are in fact required. Any input would be appreciated.


John Arnold
06-05-2008, 07:23 AM
I don't believe lintels are needed. Glass block is a type of masonry unit.

Jeff Spencer
06-05-2008, 07:48 AM
Thanks John

I wasn't sure and can't get my hands on the specs I have for glass block. I'm in the middle of a re-model and can't find where I safely stored the info for quick reference.


Dom D'Agostino
06-05-2008, 07:56 AM
From Pittsburgh Corning:

Glass block panels are non-load
bearing; adequate provisions
must be made for support of
construction above these panels.
Panels are mortared at the sill,
with jamb and head details
designed to accommodate for
building movement and lintel
deflection. The compressive
strength (for information
purposes only) of all hollow
glass block is 400 to 600 psi.;
THICKSETĀ® Series Glass Block
is 2500 psi.; and VISTABRIKĀ®
Series is 80,000 psi.

The above is found in this document, which also shows the lintel details:


Jerry Peck
06-05-2008, 05:55 PM
In addition to what Dom said:

While the IRC does not address glass unit masonry in much detail, the IBC does address it in more detail.

From the 2006 IBC. (underlining is mine)
- 2110.1 Scope. This section covers the empirical requirements for nonload-bearing glass unit masonry elements in exterior or interior walls.

Think of glass block as being like a window or a door, which are like opening in the wall ... the wall needs to be self-supporting without the window or door installed, same with no glass block installed.

Needs a lintel/shelf angle above it, which means it needs a flashing above the lintel/shelf angle, which means it needs weep holes.