Ok, so running a little behind in these updates… The below happened end on Jan into Feb
With all the roof batten work prepped – spaced, measured, levelled and packed accordingly – the roof was ready to go on.
We selected a profile called Spandek, it meets the requirements for a roof with a 2 degree pitch and unlike Klip-Lok (what have build material makers got against the letter ‘C’?!) if we need to remove an individual sheet in the future we can, handy when you don’t have a ceiling crawl space.
Thankfully Rosey and Ross were on hand and willing to help – unfortunely the weather decided to hit a heatwave (for Tassie!) and Steve was up on the roof trying to get as much done before the middle of the day. Turns out a dark roof can get pretty hot in the sun!
As the roofing sheets were laid, a layer of insulation called Space Blanket was first put down. This is a foil layer with a thin sheet of glass fibre insulation which gets sandwiched under the roofing sheets. It helps further insulate and reduced the likely hood of condensation build up under a steel roof, as well as noise from heavy rain and expansion and contraction ‘ticking’ noise that metal roofs can make when the sun comes out from behind clouds.
After a big of juggling around with sheets we needed to do a few more joins than originally thought. The longest span was too long to be a single sheet due to access issues (a truck with a tray that long wouldn’t make it up our road and through the trees) so joins were inevitable. However due to being slightly off in calculations we needed to have a couple more joins than planned. It’s amazing how being 10cm out compounds over distance and a sheet that was meant to span the house ended up being too short. All part of the learning process!
The next challenge was trimming the sheets. With so many different tools for the job but some of them not readily available for hire we opted for a metal cutting blade on the circular saw. Unlike a angle grinder it isn’t meant to heat up the cut edge too much and doesn’t create hot sparks which apparently damage Colorbond surfaces which can lead to rust spots forming over time.
The curves were cut using a cheap nibbler – a little punching bit that attached to the drill and punches out moon shaped bits of metal as it works along the cutting path. Considering a specialised tool would be at least a few hundred dollars this little drill attachment worked well for the small sections we needed it for. It has also come in handy for cutting downpipe holes from the guttering.
The cut edges are then crimped down along the gutter edge and up along the flashed (top) edges to further help water drip off the roof and also not run up the roof slope.
Also while we waited for windows to be made and gutting & flashing to arrive we then began applying the house wrap. Where blue and silver foil sarking use to be the norm now wraps are the go – they are designed to allow vapour to permeate and the house to breath but keep water out. Basically like a gore-tex jacket for a house! Breathability is important as having a damp house an lead to timber frames rotting, but not allowing any water in is, obviously also very important. We opted for a product called Proctorwrap as it suited our needs in creating a well sealed home, but not necessarily going the hole shabang of a completely air-tight home – where every penetration is triple sealed and kilometres of special tapes are required for walls, floor and ceiling which of course cost a heap more and mean everything else must be upscaled to make it a worth while investment. The water proof aspect is a back up should water get behind the cladding – if say in driving rain, where it will run down the wall and drip off the overhang.
This wrap also helps create and air gap between the cladding which will aid in insulation. This is basically how glass fibre insulation works is by trapping air as a buffer between a warm area and cold area – an air space that doesn’t have much air movement as it is relatively sealed from the outside does the same thing. Hopefully our tongue and groove vertical cladding will help create this space.
Next up guttering and realising why straight walls are the norm…