Lock up and plywood ceiling installation

The excitement that we are at lock up is tempered by the knowledge that this means we are about half way through the building process. On Thursday the boys from Rylock came down from Sydney with the double glazed units for the three panel sliding doors, as the doors were too heavy to be installed with the glass in them. Unlike the windows the glaziers were on time, they put the glass in and checked all the locks and opening mechanisms on the windows and by lunchtime we were at lockup.

Glazing in progress

After lunch the 9mm BB grade Austral Ply Hoop Pine plywood arrived from Huskisson Plywood.  The ceiling in the back bedroom had the sheep's wool insulation installed and the joints between the boards painted black ready for the ply to be put up. We cut them to size and painted the edges of the ply sheets black. Where the ceiling abutted the hemp wall I routed a 9mm wide by 5mm deep channel 10 mm in from the edge and painted this channel black, this was so that when we put the 10mm of render on the walls it will come to the edge of the black channel and look like the expressed joints between the sheets, but we will have a fixed edge to render up to.

We lifted the sheets up using a panel lifter purchased from e-bay, we had to get the 16 foot lifter so that we could use it to reach the high ceiling in the main room, but the larger lifter proved a little awkward in the smaller rooms. We did not want large screw holes in the ceiling, that would be obvious even if covered with putty, so we put the ply sheets up with glue and brads using a fix out nailer. My research showed that for a timber to timber joint Bostick Ultraset SF, which is a flooring glue, would be suitable. We bought the glue in sausages and applied it with a sausage gun in a zig zag pattern to the the joists on the inside of the sheets. We put brads in at 150 centres around the edge of each sheet and at 300 centres across the rafters passing through the centres of the sheets. The sausage gun was a breeze to use compared to my stiff old caulking gun, but the flooring glue was not meant for ceilings and was a little runny and if put on too thickly or insufficiently pushed on to the joists it dripped off. The suggestion that I put it on with a 3mm v notch spreader was impossible on a ceiling and abandoned in favour of a simple zig zag pattern. The fix out nailer was fast and east to use and a great way to attach a ceiling. The holes it left were very small, but the brads held the ceiling while the glue went off.

First piece of ply held up by the panel lifter

Applying the glue with the sausage gun

Experience showed that it was best to test each ply sheet to ensure that it fit before putting the glue on, this was after one piece had to be recut after we had put the glue on the rafters and found it did not fit in. We used 9mm spaces to try to get even gaps between the sheets. In reality some of the gaps varied a little, but a 9mm gap was wide enough to hide small variations.

First ceiling done with express joints

The first ceiling done we moved onto the next room, following the same process of blocking out between the rafters where the ply joints would be, painting the blocking and rafters behind the joints black with Resene No VOC paint, putting in the sheep's wool insulation, adding a few staples where the batts did not want to stay between the joists, measuring and cutting the sheets, which was more difficult as some of the cross rafters were not straight and painting the edges of the sheets black. We left the sheets of ply unfinished hoping that the hemp walls will prevent any mould forming on the ply, which appeared to be the only problem with leaving them unfinished.

Stapling in some of the insulation

The first sheet of ply we put up in the second room did not seem to fit. Thinking we had made the hemp walls crooked I got out my angle grinder and trimmed a little off the top corner of the wall only to discover that I had cut the sheet crooked by 10mm. The only good thing was that we discovered that the walls are really strong, but could be cut using a masonry disk on an angle grinder. After this things seemed to be going better until disaster struck. Putting up the last panel for the day the cable in the panel lifter broke and the 3/4 of a sheet of ply fell down. Thankfully we were not hurt and the sheet of ply was not damaged but the panel lifter was beyond help, the broken cable being somewhere in the mechanism that could not be seen. Before I bought the panel lifter I had checked out reviews of the panel lifters on e-bay and most people were happy with them, so I was hugely disappointed that ours broke on its second day of use. Lets hope we can get a replacement.

Since we had glue on the ceiling we then tried to put up the ply sheet by hand, it was heavier and harder than expected. The sloped ceilings made it very hard to push the ply up to the higher side and trying to get the 9mm gap right and hold the ply sheet at the same proved impossible. I thought we had got it in the right place and started putting the brads in only to find out it was way out on the other side where neither of us could see. With about half the brads put in we had to remove the sheet. It was hard work putting the ply sheet down, some of the brads pulled through the sheet while a few were pulled out in the sheet. Thankfully the sheet did not break and we wiped as much of the glue as possible off the back of the sheet and off the rafters, so we could try and put the sheet up again once we have a working panel lifter.

Ceiling in the second room, up to our unexpected stop

Broken cable on the panel lifter