Thursday November 19, Friday December 4 / Monday December 7, Monday January 25
Pack ’em in
See the previous post about ‘Putting up the Ceiling’ for an explanation about the role that insulation plays in keeping a house warm in winter and cool in summer. For insulation to be effective it has to block all gaps or cavities – including being squeezed in between studs and window frames. This serves to eliminate droughts and also provide resistance to reduce heat transfer. BUT… Batts need to be expanded to their natural depth and density – if they are squished in or compacted too tightly then they won’t be as effective. Batts also need to be fitted around wires and plumbing so there is no air gap for heat transfer.
Cut ’em up
In the walls we installed R 2.5 batts – the dimensions of each batt is 1160 high x 430 wide x 90 deep. These standard dimensions make it easy for installing batts in a standard timber frame wall – 2400 high with studs at 450 centres. I soon realised this when I had to cut each and every batt to make them fit within the 2700 high wall with studs at 400 centres! The spacing between each stud is because of the 1200 grid – dictated by the size of the four large windows and a nominal apple crate (check out the post ‘Design – Part 1’). Those early design generators that determined the grid was coming back to rub tiny glass fibres in my eyes!
More to it
Just like the ceiling, the sheets of ply for the wall were cut to size (some at Greg’s workshop) and arised by hand before being fixed in place with a nail gun. It took longer to fit the sheets of ply for the walls than it did for the ceiling – or at least that’s how it felt. Then again – there is heaps more wall than ceiling. The joins in the sheets are staggered and reflect the various heights of the windows, which reference the nominal height of stacked apple crates. We have made considerable effort to minimise wastage in material by using offcuts where possible.
My original idea was to clad all of the timber framed walls (except for the bathroom) with plywood. I even bought enough sheets of ply to do this. Then I gave the kitchen and laundry some thought and decided if the joinery was going to be black (form ply), and the splash backs too, maybe the low section of walls that wrap around the kitchen should also be black? Another example of designing as we go. It did mean borrowing a mate’s ute again, taking back some sheets of ply and swapping them for sheets of form ply. The sheets of form ply for the wall are the same thickness (9mm) as the normal ply so there is no issue with the junction where the sheets meet.
Design Tip: Here’s something I discovered and is only obvious in light: the 2400×1200 sheets of 9mm form ply are made in China and are dark brown; the 1200×600 sheets of 16mm form ply are Australian made and genuinely black in colour.
The origin of ‘normal’ ply (plywood that looks like natural timber and isn’t used for forming up concrete) can also affect the appearance of the timber. There are products available from New Zealand and Asia, as well as locally sourced from within Australia.
In the previous post I wrote about my plan to attach some sheets of caneite to parts of the walls – to improve the acoustics (dull the echo of the hard surfaces) and to provide a pin board. While I was studying at uni I used to live in a great share house with a blackboard as a splashback – this was used for all sorts of lists and doodling. I will consider incorporating one around part of the kitchen in my shack.
Costs: plywood – $992; kitchen walls (black ply) – $174; insulation – $634;
Disclaimer: Any advice contained within this blog is of a general nature only and cannot be relied upon. Details provided are in good faith and relate specifically to this project. Any author will not be held responsible for advice or information presented.