Mark Chalmers

Concepts like materiality and phenomenology are influential when you’re studying architecture.  They tend to have students either tumbling over each other – like bassett hound puppies lolloping after a marrow bone – or alternatively, giving a big Bagpuss yawn before falling asleep.

Both, in their own way, refer to how we experience buildings.  The material one suggests that we apprehend a building’s nature through the stuff it’s made from – although “materiality” has become associated with a particular kind of type of architecture.  The phenomenal one considers how we experience our whole Lebenswelt, the background to our lives: plenty of scope there for endless debate. 

However, student schemes are rarely built, so the discussion is literally academic.  Once in practice, materials rather than abstract materiality become crucial, since you can’t build unless you understand what you’re building with.  Key to that is technical knowledge, and perhaps surprisingly, getting your head around how building fabric performs becomes easier if you’re into outdoors pursuits.

Back in the day, tweeds were the only choice of clothing for outdoors types.  The milled finish of the tweed fabric gave it a close nap which was fairly wind-resistant and surprisingly water-resistant: it was also tough and thorn-proof.  However, the cloth was heavy and once you began to sweat, your cotton semmit and shirt would remain damp for hours.

The obvious analogy is with vernacular building.  Solid stone walls are built with two faces of rubble masonry and filled with “hearting” attempted to hold the building up, retain heat, and repel moisture all at once.  However, they retain dampness, much like sweaty worsted, and are slow to dry out.

By the 1970’s, tweed and dubbined leather were gradually being replaced by new kinds of waterproofs, lightweight boots and windproof fleeces.  Each garment aimed towards an economy of means, extracting higher performance from something smaller and lighter than its predecessor.  Some old-timers scorn Goretex trousers and fibrepile jackets, far less down-filled sleeping bags and Karrimats, but they represented an entirely new philosophy.

Fibrepile jackets emerged around the same time as mountaineers such as Dougal Haston ventured to the Himalayas.  They were one element in a new concept, where climbers dressed in a series of layers each of which did different things, rather than trying to find one material which is simultaneously windproof, rainproof, insulating, breathable and robust.  You split your clothes into three, using different next-to-skin, thermal insulation and weather protection fabrics to provide different qualities. 

For the waterproof “shell” jacket, W.L. Gore developed breathable fabrics like Goretex which repel water, yet wick perspiration and allow your skin to breathe.  Absorbent fabrics soak up water and hold on to it – but wicking fabrics transfer water somewhere else, without absorbing it. 

For the insulating mid-layer, Malden Mills developed “Polarfleece” fabric which by the mid-1990’s had become Polarlite and then Polartec fleece.  Around the same time, DuPont introduced the first Microfibres.  Making use of those advances, “technical” clothing was designed with functionality in mind, so garments might have a hood, windproof panels and gear loops, but lack pockets where a climbing harness would sit. 

Just as traditional cloths like tweed had become proprietary – Harris Tweed being the perfect example – high-tech synthetic fabrics were developed which mimicked traditional heavy woollen or oiled cotton textiles, but were lighter, warmer and avoided the sweatiness of traditional clothes.  Key to the concept was the knowledge that a climber can take off and put on those lightweight layers at will, with the shell as an outer skin.

Similarly, “Rationalised traditional” construction usually consists of a masonry outer skin.  That provides a robust finish which also sheds water, and inside lies a ventilated cavity drains and thermally isolates the external leaf.  The timber kit is structural but also contains the bulk of the wall’s insulation.  In simple terms, several thin layers separated by air gaps are more thermally efficient than one thick layer, and that principle was developed further in rainscreen cladding systems.

The rainscreen is perhaps the closest architectural analogy to the mountaineer’s layers, and entails splitting the external wall into two zones.  The outer leaf sheds the majority of the rain water, while the inner leaf acts as a moisture, air and vapour barrier, provides insulation and is structural.  The outer leaf isn’t waterproof – it actually allows a certain amount of moisture to penetrate – but its progress is controlled either by having a drained and back-ventilated cavity, or a pressure-equalised cavity.

As a result, the rainscreen relies on understanding capillary action and how that drives water through joints.  Goretex fabric is no different, although it harnesses capillary action rather than aiming to defeat it.

A fascinating book called Invisible on Everest, co-written by Mike Parsons who was formerly the driving force behind Karrimor, explains the difference these developments made in terms of the lives they saved in the mountains.  Karrimor was based at Accrington in Lancashire, and before a series of takeovers a few years ago, their clothing and gear were highly regarded.  Their fleeces and rucksacks in particular were unkillable and became a staple of hillwalkers, mountaineers and fell runners. 

During the mid-1990’s, a typical base layer was the Helly Hansen self-wicking top, a thin synthetic t-shirt which allowed sweat to evaporate.  The state-of-the-art mid-layer was the Karrimor “Alpiniste” Elite fleece, made from Polartec 300 fleece: not only was it very insulative, which proved to be really warm under a thin shell, but its close weave meant it was very robust and resistant to wear and tear.  The top layer is the waterproof one, a lightweight shell, which can be packed away in the rucksack if the sky is clear.

Nowadays, a technical fleece may use a mixture of fabrics: “Ultrafleece” is more wind resistant than regular fleece on the torso, and panels of stretchy fleece such as “Powerstretch” can improve articulation at elbows and shoulders.  Arguably, windproof microfleeces are the state-of-the-art right now: they insulate, block the wind and breathe out and wick sweat, too.

In fact, one criticism which present day “gear freaks” make about older fibrepiles and fleeces is that the wind blows straight through them and whilst they remain warm, once wet they stay damp for ages.  Perhaps perversely, they’ve dispensed with the layering system and are searching for a universal fabric which will do everything.  Back to the days of tweed, but using technical textiles?

Similarly, we now use “Brettstapel”, a solid timber construction system fabricated from softwood timber posts connected with timber dowels.  It’s a variation on the massivholz system which is used throughout central Europe.  Prefabricated wall, floor and roof panels made from laminated timber are secured together, then wood fibre board is attached to improve the panels’ U-value.  The timber is structural, it controls humidity by breathing, its fire-resistance is inherent and with a coating of microporous preservative, it became weather-resistant too.

Ideally, timber also becomes an internal and external finish, which keeps the building looking as timbery as possible.  Just as the Brutalists of the 1960’s aimed to cast entire buildings from concrete – floors, columns, beams and wall panels – Brettstapel aims to hold the building up, retain heat, and repel moisture all at once.  As with the outdoor gear freaks, architects sometimes question the need for all those layers which we spent years developing. 

The lesson is that we are still in pursuit of the Philosopher’s Stone – that one material to rule them all.