Terry Richardson
Apparently, only mad dogs and Englishmen go out and in the midday sun; but not all of us have the luxury of avoiding it.
For busy installers looking to benefit from the lucrative bi-folding door boom, the summer months are fertile ground. Here at TWR Trade Frames we’ve certainly noticed an upsurge in the number of our eternAL bi-folds being specified and installed.
But with such soaring temperatures many installers have been asking us about issues the good weather may bring. Such as – to what degree an aluminium bi-folding door will expand in the heat and whether it does so more than PVCu.
Dark colours
Typically, a single pane on a standard aluminium bi-fold will expand approximately I.15 millimetres every 50 degrees; so theoretically a 6 pane bi-fold could therefore expand by 6.9 millimetres every fifty degrees. And it is worth considering that dark colours, such as black, will retain and absorb more heat than lighter colours.
As such there is no harm in installers checking whether any bi-fold installations they have carried out have dropped, or come out of square, due to expansion in the heat; and if so, re-glazing the door may be necessary.
Aluminium versus PVCu
What material your bi-fold is made of can make all the difference. Aluminium holds up better than PVCu. For example at 50 degrees PVCu expands at approximately 2.5 millimetres per pane.
And at 100 degrees PVCu expands at approximately 5 millimetres per pane, compared to aluminium at approximately 2.3 millimetres per pane. The bottom line is that aluminium expands at around half the rate of PVCu, therefore making any warping or dropping less likely.
Bi-fold season
Now it’s not like the English to complain about the weather, so moving on to a more positive note it is worth mentioning that summer really is the bi-fold season and opportunities for installers are there to grab.
Bi-folds are unrivalled when it comes to ‘bringing the outside in’ and opening up living space; meaning that opening them up in the summer months will actually rapidly cool down a living space.
Despite the aforementioned concerns, problems have been minimal from the installers we work with but if any issues are experienced don’t hesitate to call the bi-fold doctor on: 0191 565 2200.
We run a bi-fold support, survey and supply service which can help inexperienced installers enter the lucrative bi-folding door market.