Volume 33, Number 7, July 1998


Off the Block

New Trends in Glass Block Installation

by Gary Good

Since the late 1930s, glass block has brought warmth and beauty to homes. Glass block is hard to beat for its ability to allow a large amount of light into a room, while at the same time, providing privacy. Throughout the years, builders and architects have used glass block for a multitude of applications, including windows, shower enclosures, accents and partitions.

If there is one reason why glass block hasn’t found greater acceptance, it’s because of the problems associated with installation. Installing glass block isn’t as easy as it looks. Although it looks to be a perfect do-it-yourself project, installing glass block can be difficult and very messy. In response, several companies have developed innovative products to make glass block installation easier, quicker and more affordable.

In 1990, Pittsburgh Corning Corporation introduced its KWiK’N EZ silicone system for installing glass block. This system makes it easier for the glazing contractor in that silicone sealant is used instead of mortar. The system consists of rigid, perimeter channels, flexible plastic spacers, glass block sealant and a joint finishing tool. The clear sealant also provides a clear, mortarless appearance. Pittsburgh Corning recommends that interior panels be 85 square feet or less and exterior panels to be no greater than 16 square feet.


A system similar to KWiK’N EZ is the BlokUp system from Glashaus in Crystal Lake, IL. The system, available as prefabricated glass block windows or as a kit, utilizes metal horizontal and vertical strips to hold the blocks in place. Silicone sealant is applied to the sides of the blocks as the panel is being built and also between the blocks after it is assembled. Unlike Pittsburgh Corning’s system, the BlokUp system has a kit that allows you to construct curved panels.

IBP Glass Block Grid System™

The Glass Block Grid System from Innovative Building Products (IBP) of Fort Worth, TX, consists of a metal grid into which glass block is inserted. The grid, available in several colors, is installed like a typical window. Each glass block is then wrapped with an insulating foam tape, inserted into the grid and then sealed. The result is an attractive and sturdy glass block installation.

IBP’s system is unique in that the grid provides the stability and integrity of the panel so a damaged or missing block doesn’t affect the structure of the panel.

This also makes replacing a block much easier than mortared glass block. The system allows for the installation of glass block pavers and for glass block skylights.

Hy-Lite Block Windows®

Instead of just a system for installing glass block, Hy-Lite Products, Inc. invented an alternative to the blocks themselves. The windows are constructed of acrylic blocks that have the appearance of glass block. Using acrylic blocks means that the windows are lighter than glass block, so lifting one of these prefabricated panels in place is easy. The windows also use standard window frames so they install like most windows, eliminating any need for sub trades or special training.

The block windows are sold through typical dealers. Because the product is marketed as a window (as opposed to a masonry product) the units comply with standard industry window tests.

Prefab Glass Block

Due to the time-consuming nature of glass block installation, many of the systems are better suited for the do-it-yourselfer than the professional contractor who charges by the hour. In response to the needs of the contractor, several companies have developed prefabricated glass block panel systems that install as regular windows. Perhaps most notable is Pittsburgh Corning’s entry into this prefab market. Its LightWise™ glass block windows come in a welded vinyl frame and use silicon sealant to seal between the blocks. They are available in 29 sizes, three glass block patterns and two vinyl frame colors.

As the popularity of glass block continues to grow, we can expect to see more innovative products to make installing glass block easier, quicker and more affordable.

KWiK’N EZ is a registered trademark of Pittsburgh Corning Corporation. IBP Glass Block Grid System is a trademark of Innovative Building Products, Inc. Hy-Lite Block Window is a registered trademark of Hy-Lite Products, Inc.

Gary Good is the marketing manager at Hy-Lite Products, Inc., the originator of acrylic block windows.


© Copyright 1998 Key Communications, Inc. All rights reserved. No reproduction of any type without expressed written permission.