From the Shard to the Gherkin to the Lloyd’s Building in London, these buildings always take peoples’ breaths away.
It’s not just the sheer engineering skill of the building or the number of floors or their often quirky shapes, for me, it’s that vast expanse of glass. Did you know there are over 7, 400 glass panes on the external skin of the Gherkin?
What may not be obvious to many is that those panes are not actually part of the building itself.
They are an ingenious glass-and-metal covering that is used to protect the buildings’ façade. These curtain walls provide an attractive yet durable and cost-effective cladding solution. While many architects are recommending the use of curtain walls for protecting historical buildings; they can also be used to protect shopping centres and hotels.
This cladding suffers from a slew of design and construction problems, which range from condensation, staining, water leakage to falling trim covers. One common one is reaching a consensus among architects, building planners, owners and developers. They are often at logger heads regarding design and function. Before you go ahead, be sure that all professionals agree and sign off on one design.
With one design agreed on, also consider these common curtain walling design issues:
MAINTENANCE IS KEY.
It is easy to visualize how stunning and aesthetically appealing your building will look when completed. Spare a thought for the maintenance which will include window washing, replacement of seals/gaskets and insulating glass. It is crucial to have a cleaning plan for the curtain wall.
One aspect of this is access to all sections of the wall. A high pressure hose can reach a few floors up, but the ensuing run off may affect your business. Can a professional window cleaner with cherry pickers? Can you only get access by dismantling the entire front façade?
BEWARE OF THE SHADOW BOX.
Shadow boxes are one method used to create the illusion of depth behind transparent sections of the wall. This is done by placing a metal sheet behind the transparent pane of glass, providing an enclosed space behind clear glass. In most situations, the top, bottom, and sides of the insulating sheet is sealed to the surrounding frame. This helps prevent the movement of warm and moist air from the building into the shadow box The problem is that over time, the change in temperature causes this to happen.
Two common problems of shadow boxes include:
- Imperfect sealing will allow warm, moist air to enter that space. This will lead to condensation and potential staining of the glass panels. If left unchecked, it can even leakage to the interior of the curtain wall. Larger surfaces are really prone to this as there are more air leaks into the shadow box, due to the large number of joints in the framing and insulation.
- Shadow boxes can also become extra hot from solar radiation, leading to degradation of the rubber seals. This disintegration can also give off gas that will stain the interior of the glass. A combination of these effects will cause the common “picture framing” effect .
The best laid plans of mice and men….you know the rest. There is no guarantee that accidents wont happen. When it does, how do you plan to replace glass? Attempting to do this from the exterior can be quite costly, especially if the replacement will require cutting through the curtain wall frame / mullion. This will usually require a redesign of the initial wall.
These common curtain walling problems can be avoided and an aesthetic and protective covering wall designed for your building. It is also pertinent to assess the build and determine if a curtain wall is the best option for cladding.
At SRL Limited, our staff will walk you through the design and construction of your curtain wall. From providing BFRC approved glass to using high grade aluminium frames to your unique specifications, SRL Limited is poised to deliver your curtain walling needs. Call us today for a quote.