Glass tops get requested for three fairly different reasons, and knowing which one you are in changes what you should order. Some people want to protect a wooden surface from heat, moisture and scratching. Some have had a top break and need it matched. And some have a base, a console or a patio frame that was always meant to carry glass and never did.
All three come down to the same three decisions: thickness, edge, and whether the glass should be tempered.
Thicker glass is stronger and reads as more substantial, and it costs more and weighs considerably more. A thin protective sheet laid over an existing wooden table is doing a completely different job from a piece of glass acting as the actual table surface across an open base, and it should not be specified the same way.
The span matters as much as the load. Glass supported around its full perimeter can be thinner than glass bridging an open gap between two pedestals, because unsupported span is where flex and failure happen.
Annealed glass is standard glass. It breaks into large sharp shards. Tempered glass is heat treated so that it is substantially stronger and, when it does break, it crumbles into small blunt pieces rather than blades.
For a dining table, a coffee table in a room with kids, or anything outdoors, tempered is the sensible specification and the cost difference is small against the consequence. One thing to know: tempered glass cannot be cut, drilled or modified after treatment. It has to be made to final dimensions from the start, which is why measuring accurately at the beginning is not optional.
Patio and outdoor furniture should be tempered without exception. Monsoon wind moves furniture, and annealed glass that gets knocked over breaks into pieces you will be finding in the yard for weeks.
Rectangles and squares are straightforward. Circles, ovals, rounded corners and radius corners are all standard work. Cutouts for umbrella poles on patio tables need the hole positioned precisely against the frame below it, so those get measured on the piece rather than estimated from a photo.
For a protective top over an existing surface, the glass usually sits flush to the edge or slightly inside it. For a top that spans a base, the overhang is a design decision as well as a structural one, since too much overhang past the support puts stress at the wrong point.
Bring the dimensions or have us measure. For anything with an unusual shape, a template is more reliable than numbers.
Send the dimensions and the shape, or ask us to come and measure it, and we will price the glass with the edge and thickness options laid out.