Dear Jim: I am remodeling my home and I plan to use new style decorative glass block windows on the exterior and for interior accents. Are they very energy efficient and are there low-cost do-it-yourself kits? -- Paul G.
Dear Paul: You have many new options: individual glass blocks, simple do-it-yourself kits, and complete ready-to-install glass block windows. There is a huge range of colors and patterns to match any decor. Choose between plastic or glass blocks and ones that are fixed or open like casements.
From an energy efficiency standpoint, glass blocks are about as efficient as most double pane thermal windows. Each glass block is actually hollow. Two halves are fused together under high temperature. When the block cools, it forms a partial vacuum, similar to an insulating Thermos bottle wall.
With all the new colors, decorative and privacy patterns, and angled blocks for simple curves, glass and plastic block walls are becoming very popular. Some of the special angled blocks allow for a curve with a radius as tight as 12 inches. They can also be used to create a contemporary angular wall.
Some designer glass blocks have ornate etched patterns in the glass and are available in color tints. Others use parallel fluted surfaces for privacy and a unique appearance or use curved fluted surfaces for continuous patterns. Optional fiber optics can be added for contemporary and varying colors.
In addition to the decorative aspects, glass block windows are secure. It would take a would-be thief quite a while to hammer his way through a standard glass block. Solid, but less efficient, security blocks are also available.
There are several glass/plastic block options for the budget-minded do-it-yourselfer. Complete glass block panels, with nailing fins or metal straps, are available to slip into the wall opening. By using various-width blocks for the center blocks, the width can be adjusted to fit most openings.
Several of the manufacturers make kits that use spacers to separate and position each block. When sealed in place with silicone, these provide an all-glass appearance. Others use natural wood between them for an elegant look.
For ventilation in the spring and fall with glass block windows, consider installing a glass block venting panel. These are small-sized hopper windows designed to fit in place of a couple of glass blocks. The glazing is made of double-walled polycarbonate (bulletproof glass) for security.
Another venting option, ideal for bathrooms, is a casement-style glass block window. These are premade units that fit into the wall opening. They often use the lightweight plastic blocks instead of the heavier glass.
Write for (instantly download -- www.dulley.com) Update Bulletin No. 402 -- buyer's guide of nine designer glass/plastic blocks and do-it-yourself window kit manufacturers, sizes, colors, patterns, features, prices and installation instructions. Please include $3 and a business-size, self-addressed stamped envelope.
James Dulley, 6906 Royalgreen Drive, Cincinnati, OH 45244.