Versatility of design: glassfibre reinforced concrete - New Zealand

Glassfibre reinforced concrete rivals many competing products in weight and durability. Tipping the scales at significantly less weight than standard concrete, and still far less than lightweight concrete, its weight, or lack thereof, is one of its key benefits, making it easier to use and install.

It’s also a very malleable product, which opens the door for it to be used in anything from public artwork to the most ornate of historical restorations.

“Glassfibre reinforced concrete is one of the most versatile building materials available to architects and engineers today,” GRC NZ’s Jamie Marryatt says. “It’s a composite material comprised of a mixture of hydraulic cement, silica sand, alkali-resistant glass fibres and water.”

The glass fibres reinforce the mortar mix, which improves its tensile strength and characteristics. “GRC was initially developed in the 1960s as a corrosion-free alternative to traditional steel-reinforced concrete and first manufactured as an exterior cladding material.”

Since the 1960s its uses have developed, and its ability to be moulded into a wide variety of complex shapes and forms has drawn architects and designers to its use for a vast array of architectural solutions.

GRC is typically manufactured to a skin thickness of 12mm, and can be cast in thinner sections. “The reduced weight of the panels makes them easier and cheaper to handle, with reduced transportation and installation costs,” Jamie says.

Perhaps the biggest attraction to GRC though, is the combination of being both lightweight and strong. “The glass fibre used has a tensile strength three to four times greater than the equivalent steel fibre, and they reduce loadings on foundations and perimeter columns, which can lead to significant savings in superstructure and foundation work if it design in from concept.”

One of the emerging uses of GRC though, is in historic restorations, primarily because of its malleability. “It can be used to accurately reproduce any small or large design, including historic ornaments, ornate patterns and complex shapes,” Jamie says. "We're currently undertaking several restoration jobs on buildings where teh rooftop and ballaster decorative features are no longer compliant, so the clients have chosen to use GRC to replace them because of the surety that it will endure the test of time and comply with regulations."

GRC NZ specialises in the use of glassfibre reinforced concrete, and works on jobs for anything from a planter box to commercial cladding.

Get in touch with GRC NZ on ArchiPro here to have a look at some of their latest work.