The beauty of using structural glass as a building material is its sheer scope and versatility,” says Peter Hazeldean, MD of structural glass specialist, Ion Glass. “You really can push the boundaries when you use glass as a building material, with some truly exciting results.”
Achieving the results and ensuring the glass is both functional and fully compliant involves detailed structural calculations and precise and accurate measurements – it’s an area of the building industry where expert advice can make all the difference. The interface between the glass and the infrastructure of the building is critical – the concealed channels, bespoke steel frames, the size and finish of the bolts or discreet brackets to fix the glass in place with minimal visual impact but, nevertheless, maximum structural importance. There is no option to ‘shave a bit off’ or ‘pad it out’ when you’re working with glass, the fit has to be flawless and inaccuracies result in costly re-manufacture and delays.
Semi-circular glass garden building
A demanding and challenging project completed by Ion Glass was an impressive and stylish semi-circular garden room built using a series of individual glass wall panels and a roof entirely constructed from glass. Innovative use of triple-laminate glass manufacture created load-bearing structural beams entirely of glass with each roof beam set at a slightly different angle to accommodate both the pitch and the curve of the roof. Each individual beam interfaces perfectly with the vertical glass fins that provide the structural integrity of the walls. The glass roof panels fit together to provide a seamless and weatherproof finish, projecting slightly over the glass walls for an optimum result.
A semi-circular glass panel set into the centre of the frame completes the roof construction and the building is finished with double glass doors, set into a discreet metal frame which is the only structural support not created from glass.
“This was an unusual and demanding construction,” comments Peter Hazeldean, “the calculations had to be exceptionally precise to ensure the finished building was structurally sound. To ensure a perfect result, the entire greenhouse was created using a wooden template to test the exact angles of the glass beams and the precise fit of all the panels. The finished result met all the client’s expectations, including automatic louvered windows to ensure the optimum growing conditions for their plants and a small entranceway in one of the walls to allow free movement of his pet tortoise.”
Glass linkway
Glass provides the optimum solution when creating a link between two disparate buildings, especially useful when adding a modern extension to a heritage building – the glass interface accommodates the differences between old and new construction and can provide a useful visual break between two architectural styles.
A recent project by Ion Glass created a glass linkway between a heritage home and a newly-constructed family garden room. One side of the linkway was formed by the original garden wall, giving the added challenge of creating a functional and stylish result that combined all the existing structural elements into one cohesive design. Designing the structural aspects of the linkway in glass avoided the introduction of an additional building material in a space that already included the brick walls of the house, the stone garden wall and the modern material of the extension.
Glazed walls were formed from a series of 12mm-thick glass panels, set into surface-mounted stainless steel floor channels and recessed wall channels, which avoided a requirement for footings. Lateral stability was achieved with the use of 33mm laminated toughened glass fins, which also provided connection points for the glass beams which support the roof panels.
For maximum integrity of the structure, the glass roof beams interlock securely with the vertical glass fins, the layers of triple-laminated glass designed and manufactured to lock accurately together. The structure was finished with a glass door opening onto the terrace, installed with self-closing hinges and a secure lock.
Curved glass balustrades
Whilst glass balustrades are readily available and popular, it’s possible to achieve a result that truly stands out from the crowds. With minimal or no visible fixings and no handrail, a fully frameless balustrade can provide an effective and compliant barrier with no impact on either the view or the building itself. Adding in curves increases the complexity of the project but can achieve spectacular results.
An internal glass balustrade installed by Ion in the top floor of a Martello tower was designed to follow the curve of the building, enclosing a mezzanine floor with stunning views of the South Coast. The glass curves flawlessly around the space and the top of the spiral staircase. “This is typical example of the deceptive simplicity of structural glass,” says Peter. “Achieving a combination of the tight curve around the spiral and the sweep of glass around the curve of the mezzanine is a testament to precise measurements, accurate manufacture and experienced installation technicians. The narrow staircase and low-height doors made it impossible to manoeuvre the glass through the building and the panels had to be raised to the top of the tower via an external hoist but it’s surprising how often we encounter examples of similar calculations being omitted at the design and costing stage.”