The weather has not been playing ball with us the past three weeks with two major cyclones ripping through or close to New Zealand and Christchurch sitting at the edge of the system and on the receiving end of wind and heavy rain. Most rain is not of concern with our type of build, but it does require consideration of the safety of the build crew as they work on scaffolding and lose peripheral vision due to raincoats. The team worked through the rain to erect the internal walls of the ground floor, then we had to wait a few days as the wind picked up, making it unsafe to hoist the wall panels into place by crane. On the upside, the wind dried out the site!
Seeing the internal walls doesn’t really give a vision of what is coming. I found the lack of external walls and ceilings prevented that sensation of what it would be like. That blue beam is part of the structural integrity of the building; a “backbone” of steel that goes from north to south along the longest length of the house and fairly centrally located on the E-W axis. A second, shorter, beam goes across the centre of the kitchen, also on a N-S axis and it provides load bearing capability for the exterior wall of the upper floor. (The upper floor is not the same size as the ground floor)
It was a rainy day when the Theca panels for the ground floor were installed, but the rain had abated so it was full steam ahead. The panels arrived on the back of a Hiab truck.
The truck parked on the north side of the house and a crane hoisted the panels in starting at the north and working anti-clockwise. The sequence is important in that the panels have to be loaded onto the truck in the correct order for unloading (so stacked in reverse assembly order), panels are assembled in sequence (so not one this side, then the next over the other side) so that they can be “locked” together, and in some cases the sequence of assembly is dictated by access. For our ground floor that wasn’t of concern, but on the upper floor the assembly started at the furthest point from the crane and worked forward.
Once the external walls are erected the mid-level floor is installed. These arrived on a second truck:
The mid-floor is not a true Theca panel and is pretty much the same as a standard build. That is because there will be either a room above or the roof will continue the panellised construction to provide the continuation of the thermal envelope.
The above photo is the ground floor guest bedroom looking through into the dressing/tea making area and ensuite (on the left), and thought he door frame into the hall and laundry beyond.
The entire ground floor assembly took 4 hours, with a further 2 hours to install the mid-floor and tidy it all up. You’ll notice the Intel wrap visible on the inside, which provides the airtight envelope. Any breach of their membrane is taped over with special tape to ensure the integrity of the envelope.
The exterior of the panels is a Pro Clima waterproof membrane called Solitex Extasana.
Of course, the very next day it was sunny and dry…. Which we were quite grateful for as it dried the house out again.
Assembly day 2 dawned as a hot and sunny day. Once again the panels were delivered loaded onto a HIab truck and were craned off in the correct sequence. This time it was important to assemble from the furthest point from the crane and move north. Here’s a sequence of photos showing the hoisting and positioning of a panel that is the side of the upstairs guest bedroom (aka my sewing room!). This room has one wall against which leans the roof over the downstairs guest bedroom. As the thermal envelope will come up the roof (rather than flat along the ceiling) we have been able to have a small access door access into the attic space for storage. The wall panel therefore shows the access door opening and did not require insulation nor membranes (Intel or Pro Clima) on the part of the wall which will be within the roof space.
When it was lowered into the final spot a great deal of attention was paid to ensuring the fit was perfect to the millimetre:
Once again, only a few hours later and the walls and ceilings had been installed.
In my next post I will explain a little about the panels themselves, how they work and the PassivHaus requirements.