Staff training WARM style 9… Out of Africa

Posted by on Jun 3, 2015 in Staff training WARM style | Comments Off on Staff training WARM style 9… Out of Africa

Staff training WARM style 9… Out of Africa

Cladding… an area I hadn’t really paid much attention to. The difference between an Engineer’s and an Architect’s approach to designing a building?

I figured we would just get some generic wood cladding like you see on most garden sheds when the time came. But then when I thought about it a bit more, I realised we’d spent all this time and money on avoiding thermal bridges and I was about to screw multiple times through all my insulation layers to hang my cladding. If this was a Passivhaus I would have just failed my heating target by introducing a multitude of point thermal bridges. In reality the thermal bridges on this project would probably be insignificant as a percentage of heat loss as my insulation isn’t very thick, but I wanted to think about how I might attach cladding as if I were trying to minimise thermal bridging to understand the difficulties encountered in Passivhaus design.

If I’d thought about it a bit earlier, maybe I should have got the woodfibre board suitable for external render e.g. http://www.backtoearth.co.uk/product/udispeed-40mm-wood-fibre-insulation-board and then we could have just rendered it… but I didn’t think about it earlier. I also wanted something quick and easy to take on and off in case we ever decided to move it, (although as it becomes more and more solid I am less and less sure that it will ever be moved!).

Also, when it came down to it, I wanted it to look a bit more interesting than a generic garden shed. So I put my Architectural hat on, and started looking at alternative materials for cladding. I even emailed the highways agency to see whether we could recycle old road signs, inspired by one that turned up in our garden during a winter storm (the answer was no – they already get recycled). My next thought was old sails, but I thought old sails are probably old for a good reason and may not stand up to the battering of a Devon rainy winter.

The inspiration came in the end from Africa. We realised we had seen a lot of wood and canvas clad structures when living in South Africa, usually a hybrid of a safari tent and wood cabin. So I googled images of yurts, safari tents and gazebo’s and eventually found an image on the internet of a canvas solution that I thought could work http://www.protectivetextile.co.uk/media_protective/image/Blinds%20for%20Hut.jpg

We decided to go for a canvas panel on the west, north and south facades. The east facade with the door and part of the south façade around the window would be conventional ship lap wood.

I contacted a couple of companies that specialise in gazebo and yurt making and finally, at the end of October, placed an order for three large canvas panels from Spiritsintent http://spiritsintent.com/, a company based in North Wales who specialise in all things canvas. Just in time, as they were all just about to head to sunnier climes for the winter (which is what we should have done). The panels duly arrived a week later.

By this time sunny dry spells were few and far between and we didn’t want to risk putting the cladding on unless the wood fibre board was bone dry. The wood fibre boards are treated such that they can be left exposed for around 8 weeks, so we wrapped the office up in some unwieldy and slug ridden black plastic that we had been using to keep weeds at bay in the vegetable garden and decided to wait for dry weather before we finished the cladding…

…and gradually over the next few months with cold fingers and much wading through mud, we installed the fabric panels on the West and North. No photos of the process I’m afraid as it was too bleak.

 

Out of Africa 1

 

Out of Africa 6

 

Out of Africa 4

We attached a wooden frame on top of the wood fibre insulation and attached the canvas to this using a combination of screws, washers and elastic, neatly whipped at the ends (at last Rowan gets to use one of the skills he learnt at sea).

Out of Africa 2

 

The screws and washer solution was dramatically cheaper than buying hooks, used on the gazebos we have seen.

So far the cladding seems to have performed very well. The North and West panels took a good battering of rain and wind over the winter and the wood fibre board behind is still in perfect condition. It’s recommended that the canvas is treated each year in the autumn and checked over the winter season, but due to the location it seems that the canvas dries out very well (when it stops raining) so fingers crossed it should last us a good few years.

I thought we may have invented a revolutionary new cladding technique for shepherd’s huts until my Dad sent me this picture taken just after the First World War…

Out of Africa 3

Coming up – installing the electrics…

Blog written by Caroline Martin

@cazzam2