Donovan Mirror and Glass

Serving Southeastern Wisconsin

Tables

Glass Options

The most popular and most economical glass option is clear. Just about any other glass type could be used as long as it is available in the needed thickness. Most pattern glass is only textured on one side, so the smooth side could be the top surface for easier cleaning, or the textured side could be used as the top surface to hide potential scratches.

Glass Thickness

Tables are usually made 3/8”, 1/2”, or 3/4” thick.

Glass strength is the most important factor to consider when determining the thickness. Thicker glass can support more weight. The overall size of the table and support bases may require glass of a minimal thickness. The amount the glass overhangs the base, as well as the distance between supports needs to be considered when purchasing a glass table.

Glass Edgework

Click here to view edgework

Bases

illustration depicting maximum glass size for a table base.As a guideline no more than a third of any dimension should overhang the base of support. Small tables usually have one base. Larger tables sometimes have two or more bases, in which case the span between supports is an additional consideration. We do not sell table bases aside from a few options using plate glass.

The image to the right illustrates this overhang guideline, and the 54" table top is the largest size that should be used with the 18" base.

Glass Weight

3/8” thick glass weighs about 4.9 lbs per square foot, 1/2" glass weighs about 6.5 lbs per square foot, and 3/4" glass weighs about 9.69 lbs per square foot. Glass tables are usually around a hundred pounds, but some of the larger dining and conference tables can be several hundred pounds.

Tempered Glass versus Annealed Glass

Tempered glass is about four times stronger than annealed glass. However, tempered glass gets its strength from stresses in the glass, which also gives it the property of breaking up into many small cubes when it does break. Except for outdoor patio furniture which usually uses thinner glass, most glass tables are made with annealed glass. If a steel hammer is used to hit the edge of 3/4" thick annealed glass, the edge will probably chip or even crack. If the hammer were used to hit the edge of 3/4" tempered glass, the glass would either hold together with no visible damage, or instantly shatter into hundreds of little cubes. There will be no glass left to support anything that was on the table.

When glass is heated to about 1150°F it becomes soft, and if cooled quickly the outer surfaces of the glass obtain a surface compression of about 10,000 psi. Because annealed glass is cooled slowly it doesn't have the stresses in the glass that tempered glass has. Tempered glass gets its strength from this compression, and will break at about 24,000 psi whereas annealed glass breaks at about 6,000 psi. This is the comparison people most often use when speaking about tempered glass being four times stronger than annealed glass. However, the compressed surface layer is only about 20% of the thickness of the glass, and the inner 60% of the glass is under tension. All that has to be done to break tempered glass is to penetrate the compressed surface layer, which releases the tension within the glass by thoroughly shattering it.

Seating Approximations

The number of people that a table will accomodate obviously depends on the size of the chairs and the amount of room each person prefers. However, approximate seating chart information is provided in the link below.

Seating Charts