Thursday, March 7, 2013

Happening tin

A big day today - the tin starts going down! :)

My day started early in Melbourne, to swing past Bowens to pick up as many rolls of insulation as the Hilux could carry (8, in case you're wondering, plus the three rolls of rockwool on the back seat), then Bunnings for more roofing screws and then on up to Tallarook.

I made it on site not long before the first delivery driver arrived carrying all the roofing iron and flashings. He pulled in with a 9m fixed tray truck, with no crane or tipper and so it was down to me and the bobfork to unload him.

The first pack of iron went pretty well, but I didn't quite have the second (my 9m sheets) in the middle and so as soon as I lifted them off the deck they tipped over and slid down the hill. They don't appear to be damaged...

The third was more difficult as it was simply too heavy for the bobcat to lift without tipping onto its nose. This pack I ratchet strapped to the forks and lifted as clear of the truck deck as possible, while the driver drove out from underneath them, then dropped them to the deck as quickly as I could to avoid tipping over. It all happened so quickly in the end, I don't remember if it worked but we got them off without damage so all's well...

Shortly thereafter Savva the Plumber arrived and we all got stuck into the job of installing the roofing iron.

First up - the Z flashing over the top of the Hebel panels, screwed at 200mm centres. The leading edge of the tin will be screwed to this flashing and into the Hebel itself, and the whole lot glued down using a fire-proof polyurethane sealant.

Next, the space between the flashing and the first batten is filled with Rockwool, which will seal off the corrugations in the iron so that no stray embers can enter the roof space. Not that they could anyway, because it's filled with glasswool insulation and the wall cavity is sealed by the flashing, but this is the approved BAL-FZ construction method which we have to adhere to.

A little while later and we have nearly one half of the upper storey covered. It's not completely screwed down yet, but there's enough in it at the moment to keep it from going anywhere and we'll finish screwing it down later.

In our design we have no fascias, with the guttering screwing directly to the roofing sheets. We'll taper the overhang from one end of the building to the other in order to produce the required fall in the guttering, towards the downpipe.

The iron is not yet screwed down at its leading edge, so it's not quite flush with the Hebel yet. I still need to get in there with the polyurethane sealant, (not to mention, finishing installing the infills above the windows) so we'll wait until I've finished that to screw it down finally.

There is absolutely nowhere for an ember to get into the roof structure and start a fire - the whole thing is stuffed full of non-combistible insulation. The ridge capping will be filled with Rockwool too.

Shortly after lunch the Bowens truck arrived with the rest of the insulation, but unlike most of the truckies who visit our place this guy had very little idea. He drove in almost all the way down to the house site, but was blocked by the roofing sheets on the road. We unloaded him and he proceeded to reverse back up, but kept alternately slipping his clutch and then dropping it, provoking nothing but wheelspin and digging himself a hole. I tried to encourage him to take it slowly (the roofing delivery driver drove out with ease) but in his broken English he basically said "no can" and even with a sheet of reo steel under his wheels, he went nowhere in a cloud of tyre smoke.

In the end I offered to pull him out with the bobcat, and so I went cross-country to get past him and we hooked up a chain to the bobcat. But before I could take up the tension he started reversing out slowly, and I never did get the chain tight before we reached the top of the hill.


After that we had very few interruptions :)

So come the end of day #1 of roofing, and we have the dwelling sheets installed with only a little stuffing around tomorrow to finish it off.


  1. Nice site (both web and building site) we are also self building FYI.

    One question what are you going to use to finish / plaster / seal the hebel panels?

    Cheers Ron.

    1. Hi Ron,

      I actually haven't done a great deal of research into how the Hebel is finished. I know it's a rendered (or bagged) sort of finish, but I have it in my memory that it's not actually a cement-based render and I'm supposed to use a product designed specifically for Hebel.

      This is another of those things sitting in the back of my mind which occasionally gives me a nudge, which I keep shoving back behind other more immediate concerns :) It'll be pretty immediate soon though, once I get all of the Hebel up...