Harting 8: Insulation underway

The north side is almost done. The west gable is done already

It's been awhile since I updated this blog - mostly due to being up the walls at work and on the building site. Since the last update, our insulation has been started. 229 bales (at 1.5m^2 a bale) of anthracite coloured insulation was delivered - a truckload basically. The panels are 50cm high and 14cm thick. They have a UWert of 0.032 W/K/m^2 (watt, Kelvin, square metre) - so they are at the more expensive end of the choices available. I went for those because the next less expensive (0.035) would have meant I would have had to get 16cm thick boards - not much of a problem in itself, but because the windows downstairs were just "swapped out" (i.e. not moved out flush with the old wall like upstairs), with 16cm insulation, they would have been even further back in the wall. As there wasn't all that much difference in the price, we went for the 0.032 boards.

Compriband seals at the top of the wall

I watched the three men doing the insulation for awhile to see how they were doing it. First, I had to spray the old plaster with a kind of glue. That bound all the dust together and kept the plaster from crumbling. Next, they set a 14cm stiff plastic profile around the base of the house - 40cm from the ground. This works as a plinth as well as a base for the first ring of insulation boards. Later, when the scaffolding is gone, I will dig a channel 30cm deep all around the house and the plinth can be finished to below ground level, for optimum insulation. Once the profile was in place, they used a kind of soft, sticky mortar to glue the boards into place. When the whole house is finished, each t-joint will be screwed into the original wall, so there is zero movement. At the top, where the wall meets the roof, they used compriband to have a proper joint that still allows some movement.

It looks as though setting insulation boards is fast work, but windows and doors do slow the whole thing down considerably. They had to put a kind of plastic net around each window - probably so they can plaster the reveal properly. These plastic pieces needed to be aligned perfectly (i.e. plumb) - otherwise the reveal will look wrong later.

I was quite fascinated at how accurate their work was - cutting the boards etc and fitting them was millimetre work - their joints were practically non-existent. Where there were joints, they used an insulating expanding foam to fill them. Later, when the whole house is done, they will go back over the facade with leveling knives (which work kind of like a cheese grater) and level any foam or boards with a belly.

Meanwhile, Niedermaier's crew and Uli were working inside, doing the heating and electricity, respectively. The plumbing to the kitchen and bath was already finished when I wrote the last post. Since then they were basically holed away up in the attic doing the 1000l tank, the attached electronics and the piping. The attic is starting to look like a brewery, with all the pipes and tanks. They are finished for the time being. They still have to install pipes to the bathroom downstairs (which shouldn't be too much of a problem) and as soon as the plastering is done inside, they will be back to do the underfloor heating. Then, I can (finally) order the concrete floor.

Apropos plastering, Chrisch is going to come over this coming Friday (26th July) and set the steel profiles. They need to set overnight. On Saturday we are going to tear into the plastering. He has a plastering machine and I ordered the plaster the other day. We have two palettes of the stuff, but I'm going to ask Brenninger (the local building supplier) to have another one handy in the likely case that we will run out if we need to work into Sunday too. I already stapled plastic protective sheeting in place on our inside ceiling - the plastering machine is basically a compressor tied to a mixer with a 20m long pipe for splattering plaster. I foresee plaster all over the timber inside, so better safe than sorry.

Below are some more photos of the progress.