Why many designs aren’t so Grand

One curious feature of homebuilding and makeover shows ...

One curious feature of homebuilding and makeover shows – which very often have a strong emphasis on sustainability – is the almost total absence of PVC-U doors and windows, despite their huge popularity in the ‘real’ world. We consider why the environmental benefits of these high-performance products seem to be determinedly ignored.

The hey-day of the TV home makeover or homebuilding show is long past. Broadcast schedules in the 90s and early noughties were packed with them and you could barely turn on the TV without being presented with Carol Smillie, Anna Ryder Richardson, Linda Barker and the ever-stylish Laurence Llewelyn-Bowen. 


While LLB – by now almost a National Institution – still pops up on the likes of DIY SOS – The Big Build, the makeover shows (with the notable exception of DIY SOS) still made are consigned to the audience no-man’s-land of daytime; leaving primetime to the ‘build’ shows of Kevin McCloud and George Clarke.

The narratives of Grand Designs may now be over-familiar

While the ‘over-budget/ over-time/ builder’s walked off/ we’ll manage it ourselves’ narratives of Grand Designs may now be over-familiar; there’s no denying the breadth and the scale of the dozens and dozens of houses this now venerable show has covered.

Super-frequent themes of builds on Grand Designs are building performance, energy efficiency and sustainability – and at levels way in excess of those demanded by planning diktats or Building Regulations.

Such builds vary from two hippies erecting a Hobbit hole in a field in France from entirely reclaimed materials; to ultimate uber-modern, brutalist Passivhaus homes. In each, the full range of energy efficient measures is usually deployed – whether with mud-clad straw bale walls and turf-covered roofs; or the brutalists with ground source heat pumps and solar showering.

In terms of glazing, timber and aluminium...

In terms of glazing, you get the gamut between salvaged windows to huge expanses of ‘switchable glass’ that becomes opaque when you pass a voltage through it (with one homeowner proudly declaring that he saved £30,000 on his windows. How much did he pay!?)

The window surrounds, though, are always timber, or aluminium, and what you never, ever see is PVC-U – despite the show’s emphasis on efficiency and sustainability; and it is truly baffling that it is so overlooked, especially in the environmental context.

Dealing with timber first, it is obviously renewable and, although relatively high maintenance, good quality joinery has a decent lifespan. What it isn’t very often, though, is recyclable. So, while the patchwork glazed windows and walls created from salvage items are fantastic; the destination for most scrap timber – when treated or painted – is landfill. Strictly speaking, you shouldn’t really even burn the stuff, as it is carcinogenic.

Aluminium, on the other hand, is obviously – like most metals – entirely recyclable: albeit at a huge energy cost, given the need for it to be re-smelted. It’s also plainly not renewable and that’s not to mention the massive amount of embedded energy required to get the stuff out of the ground, shipped to wherever it’s going and then processed. 


And yet, both these materials seem to be preferred in the eco-houses featured on TV.

We know PVC-U isn’t perfect

We know PVC-U isn’t perfect – its reliance on a fossil fuel in part as a raw material is the primary one – yet it’s a relatively minor element, while its other prime component is salt: which exists in abundance.

Furthermore, the life expectancy of a PVC-U window is considerable. Where closed loop manufacture is in play, the life cycle of a product involves recovering and repurposing materials for future use. In the case of PVC-U windows, current expectation is that the plastic element can be re-used up to 10 times. With each window having an official minimum life expectancy of 35 years (Source: BRE); that means the plastic can be used in manufacture for up to 350 years!

Better still, the re-use of PVC-U is an example of ‘upcycling’. One of the issues with single-use plastics (like water bottles) is that even when recycled, they don’t find their way into equivalent products: it is more often downcycled into things like cheap contract carpet.

This is not the case for PVC-U: re-processing PVC-U imbues it with additional structural strength and, post-extrusion, results in recycled product being technically superior to those made from virgin material, because the process creates better dispersion of material elements.

Given the case for PVC-U in both the energy efficiency and sustainability contexts, it is a wonder that Grand Designs – or rather the grand designers of the houses it features – haven’t cottoned on yet.

In fact, the resistance to the material seems almost wilful. In which case, the question must be asked if building specifiers have even seen contemporary PVC-U windows, with their slim sightlines, modern colour ranges and most importantly, their high recycled content rates.

Going forward...

Going forward, if these designs want to be grander, then perhaps designers need to be less so and start to appreciate that timber and metal are not necessarily the greenest materials available to them and, if they’re serious about performance and sustainability, incorporate more plastic into their palaces.

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