Here we are at the live event As you can see now
there’s quite a lot of progress since last time. We’ve actually put the kicker bricks
as they’re called, around the bottom of the timber frame panels there. We’ve erected the
scaffold. We’ve actually got this far with erecting the steelwork and the structural
TEK frame. There is quite a bit of steel in the front of this house that you can see.
Obviously that opening there is about 8 metres wide and there will be a big bi-fold door
in there. I’ll just show you a couple of little details. You see, this breather paper, it’s
called Wraptite, and it’s a self-adhesive paper. And that is what is going to give us,
or largely contribute towards, the airtightness of the whole frame. And what happens is that
every time we butt up a panel, like that there you can see that gap between it, there will
be a strip of that, again self-adhesive, over everywhere. So in theory there are no joints
in the structure at all. Also, this being a Passivhaus, it’s going to be extremely highly
insulated. On top of this 142mm tape panel, highly insulated, 100mm of Kooltherm. Even
more insulation. Then coming down here we’ll have a cavity. Then we’ll have some brickwork.
Now you might notice that these bricks are not your standard sort of English brick. These
are a continental brick. It’s not so deep, it’s not so wide, but it’s quite a bit longer.
And when we lay it, it will be in a kind of a broken bond fashion like that which should
look good I think. So this is a SIPs panel. This is what it consists of. A SIPs panel
is just a Structurally Insulated Panel. This is a piece of TEK, which is exactly the same
as this, which is a Kingspan SIPs panel. As you can see it’s a sandwich of 2 layers of
15mm OSB, which is Oriented Strand Board. And it’s filled with a polyurethane foam.
In the manufacturing process this actually expands and sticks the two parts together.
So that’s the basic SIPs or TEK panel. The pros and cons of using a SIPs panel, I guess
the main pros are the fact that it’s going to be very airtight. Also, there is very little
thermal bridging. What do we mean by thermal bridging? Well, anything that crosses from
inside to outside has a potential to transfer heat from inside to outside. And with a SIPs
panel, which is effectively just a foam filled core, the thermal transmittance across that
panel is greatly reduced. There is timber in there, especially if you’ve got some load-bearing
elements like point loads where you might need to support some heavy weights above,
and there is timber top and bottom. But compared to say a standard timber frame there is a
lot less timber so therefore a lot less thermal bridging. And of course each joint is using
silicone bonded to each other. Some joints have an expanding foam in there. But the whole
thing becomes airtight really. We think it’s gone pretty well so far. Of course there’ve
been one or two hiccups as there always are in building, but so far I think we’re pretty
happy. And if it continues like this we will be.