1. The Look
Aluminium windows play a major role in defining the overall look of the elevations – in this era of big glass, increasingly so – and therefore it’s worth prioritising the look. Firstly, concentrate on achieving slim sightlines. Secondly, look at the way the opening and fixed glass elements look side by side. ‘Flush’ is the key word here.
“Many architects and homeowners want a system in which all units are identical, whether the window is fixed, opening, or motorised (an increasingly popular option for high-level windows or when windows are used to provide automatic ventilation),” says Andy Trewick from Velfac. “Uniform sightlines result in stylish, seamless exterior façades.”
Origin’s flush exterior and interior casement achieves pleasing results, too.
2. The Price
Make sure that you are comparing like for like when it comes to quotes from different suppliers — assessing things like locks, handles, any required pressings and so on. There is likely to be a huge range in quotes, but don’t forget that this is more than a pricing game: look for lead-in times (Origin offers a lead time of one week on its main colours.)
Don’t forget that, as most systems require specialist fitting, you’ll need to co-ordinate with a local approved installation firm if the window company doesn’t offer a fitting service.
3. Look at the Quality of the Finish
There can be a huge variety in the quality of the aluminium windows themselves. “Good quality aluminium should have a perfectly smooth and consistent finish, while poor quality may have pitting from when the profile has been heated during powder coating,” says Neil Ginger, Origin Global’s CEO.
“A smooth finish is achieved by polishing the die after each extrusion run, to reduce corrosion and avoid contamination on the surface, giving a high-quality finish ready for the powder coating process,” he continues.
4. Security
Most windows and doors manufacturers aim to talk up their products’ security but now, thanks to changes to Part Q of the Building Regulations and the Secured By Design standards, there are measurable ways of ensuring your choice ticks the boxes.
The new Part Q came into effect on 1 October 2015 and requires accessible windows (basement, ground floor and other easily accessible windows) in new builds to be made to a design that has been shown through testing to meet the security requirements of British Standards Publication PAS 24:2012. Part Q does not apply for projects where initial notice was submitted before 1 October 2015, provided the work is started on site before 1 October 2016.
5. Build Quality
The way the window is put together can vary a lot from one supplier to the next. For example, when it comes to composite systems – which combine two materials, usually timber on the inside and aluminium externally – ensure that the external and internal frame elements are distinct (rather than, for instance, comprising a wooden frame clad on to an aluminium skin). Also ask where the key elements originated and where they were actually manufactured.