GLASS ROOFLIGHTS
The Elephant in the Roof Paul Trace from Stella Rooflight discusses the practicalities involved in specifying large rooflights As a bespoke rooflight manufacturer we often see grand plans with expansive areas of roof glazing, as architects continue to seek innovative ways in which to exploit natural daylight. As much as bespoke rooflights can certainly help bring these designs to life, there are some important factors that need to be considered when the glazing is turned from drawing to reality. In recent years we have noticed a trend towards larger rooflights, with sizes regularly exceeding 2500mm in width, height or both. While Stella can certainly accommodate these, one has to appreciate the practicalities of weight, transportation and cost. It stands to reason that the larger the rooflight, the thicker the glass will need to be, therefore as rooflight sizes get bigger their weight can increase exponentially. In context, our double glazed units comprising of 4mm thick glass weigh 20kgs per square metre and those using 6mm are 30kgs per square metre. Triple glazed units are 30kgs and 45kgs respectively. Add the stainless steel frames and hardwood liners into the equation and you can start to see how even a modest sized rooflight can weigh something akin to a small elephant! Indeed it’s not uncommon for us to produce rooflights weighing in excess of 200kg. The reality is that when you scale things up even the simplest plans can start to become complex - a truth that
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should be all too familiar to architects. But before drawing that large rectangle on a roof plan, it is important to consider how the rooflight is going to be lifted from the ground to roof level and what the weight implications might be for the structure. Stella can weld stainless eyelets to the rooflight frame to aid the lifting process and we would suggest doing this on frames
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