Five things to consider when choosing a table base for your granite or marble table top.
1) Dimensions of your table top
When a customer asks for advice on selecting a table base for a granite or marble table top, the first question we always ask is “What is the size of your top and how thick is it?”
Obviously, the bigger the table top, the larger the base that you will need. Most of our table bases can hold a large amount of weight. After all, we are talking about cast iron and steel tubing. It would take a huge amount of weight to crush a table base. The thing that we are concerned with is tipping. If you use a table base that is too small it might tip over (a very bad thing).
With very heavy tops we also occasionally experience flexing in the steel column. When all that weight is balanced on a single column and bolt in the center of a large table it may feel “spongy”.
Granite and marble table tops typically come in either 2cm (approximately ¾” thick) or 3cm (approximately 1 1/8” thick). 2cm granite weighs approximately 13 lbs per square foot. 3cm granite weighs approximately 20 lbs. per square foot. Therefore a 48” x 48” x 3cm granite top will weigh about 320 lbs. That is a lot of weight to try and balance on the center point of a large table.
If you have a choice of thickness of your table top we would highly recommend the thinner 2cm granite. It has all of the beauty and functionality of a thicker top without as much weight.
2) Height of the table
The taller the table, the more likely it is to tip over. As you raise the table top you are raising the center of gravity. That being said, it simply means that you should consider a larger or heavier table base. Where a 22” diameter table base may be just fine at standard dining height for a 36” round top, we usually advise going up to a 28” diameter table base for the same table at bar height.
3) Table base style
When it comes to choosing a table base for a granite table top, the style of the base can come into play. Vintage style bases have an advantage over the more contemporary bases because the column is usually made of cast iron. There are two reasons to recommend a base with a cast iron column. First, they are usually heavier than an equivalent size contemporary base with a steel column, and second, a cast iron column won’t flex. We rarely recommend an aluminum table base for a granite or marble table top. The aluminum bases are just too light to keep a table with a heavy top steady.
4) The number of columns
In the last few years we have introduced some table bases with multiple columns (RFL750x3, RSQ750x4, B36X5, V2230, and the Bruni series). The advantage of these bases is that the load is now distributed over a wider area and it eliminates the problem of flexing. An alternative to a single base with multiple columns is to place three or four smaller bases under the table. Three small disk bases clustered under a large granite table will accomplish the same goal. It will provide sufficient weight and multiple columns under the table.
5) Attaching the table base to the table top
All of the granite fabricators that we work with recommend that a sub-top be glued to the underside of the granite. The sub-top is usually a ¾” – 1” thick piece of plywood or MDF (medium density fiberboard.)
By gluing a wood sub-top with either epoxy or construction adhesive to the underside of the stone top it allows the base to be screwed to the top without penetrating the stone. Screwing into the granite would create a weak point in the stone. It also allows for the base and top to be separated in the future if needed.
The sub-top can be sized smaller than the granite table top so that it will not be noticeable under the table top when you look down at the table. Some fabricators will slightly bevel the edge of the sub-top and paint it black (this will cause it to kind of disappear under the table.)
A note of caution
One final thing to keep in mind. All of the above recommendations and the recommended table bases on the Tablebases.com website are based strictly on industry “rules of thumb” and the experience of our customers over many years. A base that works in one situation might not work for you. When you call us to help select a table base for your top, we are going to give you the best advice available. But, a base that might work fine in a residential application may be totally inappropriate in a busy commercial situation, or vise-versa. A wobbly table is rarely caused by a defective table base. It is usually because the table base is too small, or too light, or too much weight on a single column, or the floor is uneven, or the screws are not holding in the sub-top, or any number of factors that we are totally unaware of. Choose your table base carefully. It should always be large enough and heavy enough to keep your table steady and safe.
Granite and marble are beautiful and durable materials that make wonderful table tops. If you keep in mind the above information when selecting a table base from the large variety of very attractive table bases from Tablebases.com you should have a beautiful table that will last for many years.
