I n t h e K n o w
Considerations for Walkable Skylights
lass floors can be used in a wide variety of
applications, and the walkable skylight is one that
continues to rise in popularity.
(BIM) details and site condition information
available to architects ahead of time.
“It’s all about being able to validate all the things
architects need—from energy code compliance to
Here are three factors to consider when design-
ing for a skylight that will also serve as a glass floor: testing and performance values,” says Conklin.
- Ease of Implementation: Many factors go
2 - Glass System Makeup: The makeup of a walk-
able skylight can vary from project to project depending
on what needs to be achieved on the exterior and interior.
“Do you want a clear skylight?” Ingui asks.
“Does it need a texture that makes it less slippery?
Is it being used for residential, low-traffic use, or
is a commercial application?”
The exterior glass is often laminated for struc-
tural purposes. On the interior side, the system
may include an insulating glass component for
Glass Flooring Systems, for example, uses a
stepped framing system in which the glass that
will be walked on is not in direct contact with the
insulating glass unit (IGU) spacer. Otherwise, live
loads, snowloads and the weight of the glass itself
can affect the integrity of the spacer.
into the design, engineering and implementation of a
walkable skylight. However, architects usually don’t
have time to hash out every little detail of the skylight.
Often times, architects are looking for some-
thing pre-fabricated that they can drop into their
drawings without complications,” says Wayne
Conklin, owner of Glass Flooring Systems.
They’re seeking the path of least resistance.”
Michael Ingui of Baxt Ingui Architects has
worked on a dozen projects, primarily high-end resi-
dential applications, that include a walkable skylight.
It makes a big difference if a contractor can
basically just buy it and put it in,” he says. “The
ease of installation can be the difference in
whether or not [the walkable skylight] is actually
incorporated into the project’s design.”
Additionally, it’s critical to find a supplier that
Inside the building, daylighting is the most
makes AutoCAD, Building Information Modeling obvious driver in the use of skylights, so an archi-
tect may want to select glass types that maximize
this. Low-E coatings, colored interlayers and clear
or frosted glass textures may also be used.
Being able to have a system you can custom-
ize in this way that is also easy for contractors to
install is really a win-win,” says Ingui.
- Testing and Performance Values: Virtually
all of the factors discussed above involve some kind of
testing, starting with performance values.
“Architects are held to the standard of energy
code compliance,” says Conklin. “And it’s about
the whole building envelope. You can’t say, ‘I’m
going to be energy-code-compliant with the entire
building, except for this part.’”
Air and water infiltration are important aspects
of the system that must be tested, and anti-slip
textures may be required to meet slip-resistance
testing such as ASTM c1028 or UL 410. In some
locations, impact testing may also be required.
Finally, having many images of past projects
and applications on hand is critical to getting a
client to buy in to the idea of a walkable skylight.
“For many of these clients, seeing is believing,”
says Ingui. AGG
Walkable skylight manufacturers should have testing, detail information and
engineering readily available for ease of implementation for architects. Pictured
is an example of an exterior walkable skylight pedestal paver detail.
Architects’ Guide to Glass & Metal