As Featured in Building Products Magazine - 01/18
Michael Metcalfe, commercial sales manager at Pilkington United Kingdom Limited, part of the NSG Group, offers his top tips for specifying glass for use in commercial buildings.
From city-centre monumental buildings to small-town car dealerships, most commercial buildings today incorporate a significant amount of glazing and glass is now a defining part of how the built environment looks. It is also used for much more than simply protecting occupants from the elements.
As such, the demands placed on glass have changed over the last few years. So, what factors need to be considered when specifying for a commercial project?
1. Be mindful of temperature.
More than 25% of the heat from public buildings escapes through its closed windows. The additional costs this brings combined with tightening government regulations on energy efficiency mean those specifying in the commercial sector need to be fully aware of the insulating glass units options available to them.
Low emissivity, or ‘low-e’ glass, is designed to prevent heat escaping from a building. It has a neutral coating that dramatically reduces heat transfer and reflects interior heat back into the internal space.
Compared with uncoated double glazing, a low-e coated glass can more than double the energy efficiency of a space. It has become an essential component of schemes where large portions of the envelope are glazed.
Another issue that can arise when a building has large glazed areas is actually heat buildup. This happens when too much of the sun’s energy streams in through the glass, raising the temperature inside in the same way as a greenhouse. This is an important consideration for any south and west-facing buildings where a lot of direct sunlight will be able to enter.
It’s possible to combat this with a solar control coating, which is designed to filter out the invisible but high-energy infrared radiation that carries much of the heat energy in sunlight. This means spaces can still be filled with daylight, but that the over-heating effect is reduced, and where previously solar-control glass would require a heavy tint to work, it can now be specified as a clear pane thanks to technology advances.
2. Focus on security.
As well as acting as a filter for the light entering and leaving a building, glass also forms a physical barrier between inside and out. With this in mind, it’s important to think about the security capabilities of the system, especially for buildings with more advanced needs such as car showrooms, jewellers and court houses.
Laminated glass typically comprises of two panes of glass that are bonded together – should one of the panes break, then there is still another intact. This can enable the system to withstand bullet or blast resistance as well as repeated blows from heavy objects. The bonding of the glass holds the panes together in case of damage, with the fragments adhering strongly to the interlayer, while the resistant cushioning effect dissipates the energy.
3. Toughen up.
It’s also worth considering if the system will be needed to stand up to high winds and mechanical impacts. Toughened glass is made by subjecting it to a special heating and cooling process whereby high compressive stresses are set up at the surfaces with balancing tensile stresses in the centre, making it up to five times tougher than untreated glass.
Because of this increased strength, it allows architects and builders far greater scope in their use of glass in buildings.
4. Consider self-cleaning glass.
The time, energy and money that goes into keeping a building looking pristine has already convinced many specifiers to choose self-cleaning glass. Once installed, all that’s needed to help keep the glass clean is sunlight and rain.
It works in two stages. First, the coating reacts with daylight to break down the dirt. The second stage is based on the ‘water loving’ hydrophilic coating which spreads water over the surface to form a thin film. This then helps to wash the dirt away, preventing the formation of drying spots and streaks, meaning the most a person would ever have to do is spray the glass with a hose in very dry conditions.
Self-cleaning glass is very versatile and available with additional properties, such as thermal insulation, safety, solar and noise control.
5. Use of colour.
Different colours can be achieved on a building by specifying a tinted or screen-printed pane.
Stoke-on-Trent City Council’s headquarters are an example of this in use. Using a cutting-edge glazing system combined with bespoke screen printing, the building now displays a kaleidoscope of colour inspired by world famous potter Clarice Cliff.
Five colours: green, blue, red, yellow and white, all drawn from the colour pallet of Cliff’s designs, are arranged along all of the façades in a geometric pattern reminiscent of the potter’s distinct style, giving the building a striking, unique design.
Following these tips can help specifiers go above and beyond for their customers, enabling building occupiers to save money on heating, maintenance and provide a comfortable and attractive environment for staff and customers.
For more advice on the different types of glass available for installation in commercial projects, visit: www.pilkington.co.uk/.