Glass Balustrades - Information

The purpose of frameless glass balustrades is to create a physical (safety) barrier without creating a visual barrier. The challenge is always to build in sufficient strength, but without sacrificing good, scenic views. Keep in mind that safety always comes first. A structural engineer can be appointed to design and/or sign off a glass balustrade project.

Frameless glass balustrades differ in height from 1m to 1,2m. It requires at least 12mm thick toughened glass that can be fixed in different ways.

• With Spigots:
   A spigot is a strong, rocket shaped, stainless steel glass holder that clamps on the bottom of the glass to hold it in a upright position. In order to get a strong and safe glass barrier/fence, we core drill 40 or 50mm diameter holes down into concrete. The depth can vary between 120 to 150mm depending on the type of spigot and the height of the glass. This drilling must be controlled, precise and perfectly vertical (it can be done through tiles if need be). When the holes have been drilled the concrete must be soaked with clean water. While the concrete soaks, we clamp the spigots to the glass. After removing all excess water, we pour the cement (specialized products by Sika or ABE) into the first few holes. Then we start planting the panels upright with the rod of the spigot going into the concrete. If the concrete has not been soaked, it will extract moisture from your mix and leave you suddenly unable to move or make final adjustments to your glass.
  
  Some spigots come with a flange that will enable you to bolt them down into the concrete.
   
• Trenching:
  During Construction of a building, a concrete trench can be created into which glass panels are inserted to stand upright. This method does not require any metal fittings or clamps. The trench should be level and straight. Ideal dimensions for this trench is 60mm wide and 120mm deep. As with the spigots, the concrete should be soaked before flowing your mix into it. Glass should stand on spacers or bubble seal for protection. One advantage of trenching is that glass panels can be wider than usual, since we are not limited by certain anchor points. The logo (that shows the glass has been toughened) must be visible (by law) and cannot be submerged in the trench. Planning these jobs out is all important for once the cement sets, the position or height of the glass cannot be altered. The down side of this method is the relatively big operation to replace a panel in the event that it should break (highly unlikely).
  
  An alternative method is to use a steel U-channel for a trench.
   
• Side-fix (face-fix)
  To fix glass to the side of a concrete face can be done with studs (some call it ‘single point fixings’). Both the horizontal and vertical distance between studs are very important factors for safety and should be considered together with the height and width of the glass. With the side-fix system, we fix stainless steel threaded rods with chemical mortar into pre-drilled horizontal holes. The proper cleaning out of these holes before injecting the chemical mortar, is one of the most important actions during construction. Stainless steel studs are then screwed onto the rods, creating a flat, vertical surface to bolt the glass against. The studs act as spacers to space the glass away from the wall. The glass is separated from the metal with pvc washers.

A balustrade guarding the edge of any balcony, bridge, flat roof or similar place more than 1m above the adjacent ground or floor level shall be not less than 1m in height and shall not have any opening that permits the passage of a 100mm diameter ball. These requirements also apply to any interior balcony or any mezzanine floor (SANS 10400 – part D)

Balustrading guarding a swimming pool or swimming bath shall not be less than 1,2m high measured from the ground level, and shall not contain any opening which will permit the passage of a 100mm diameter ball (SANS 10400 – part D)