Drywall almost done

This week the last of the drywall is being installed and then, the panels will be taped & topped with gypsum topping. Parallel to that, the lathing on the exterior continues and we expect to see scratch coat by the end of the week. This is the time to nail down finishes decisions- tiles, wood floors, stone etc. Sometimes, the materials picked earlier are no longer available and alternatives need to be found.
The photo shows the upper floor clerestory with the high windows we'll use to vent the hot air out in those warm summer nights (yeah, not this year- but in general). The drywall on the jambs and head is still missing.

Snug Fit

On the weekends, Grit and I are also doing some work on the site- like a few days back when we discovered that the A/C sub forgot to install the vent pipe into the chimney up to he roof. Unfortunately, the whole chimney has been lathed and the only opening into it in on the main level was a small gap behind the BBQ counter. Everyone tried to get through the small hole, but failed (including myself). So Grit had to exhale and slide through the gap, take a reciprocal saw, some pipe fittings, glue and a ladder along with a headlamp to the inside of the chimney, cut the holes and put the pipe together. The photo shows her exiting the chimney- quite a snug fit I would say.

Drywalling

With most of the rough items completed, the dywallers moved in and started to cover the walls and ceilings with gyp board. Since we are always on the lookout for new stuff, we are trying a special sound-blocking gypsum panel in the basement next to the rec room. The product is called Quietrock 525- A composite panel consisting of one layer of gypsum and one of a cementitious compound. The manufacturer claims that the sound blocking quality is superior to a lot of standard assemblies (they say it is as good as 6 layers of regular gyp board- and that's how they justify the high price- it costs about 6 times the amount of regular drywall.) We are using it only in a small areas (actually only 2 panels) and we'll see, whether it really lives up to it's promise.
The rough drywall should be done by the end of the week- then the joints will get taped and topped and a skimcoat will be applied over the panels.
The photo shows the living room walls & ceiling- Note the sloped light fixtures in the underside of the stair to the basement and the taped-off air return above the powder room door to the left to protect the ducting from dust during construction.

Installing the Air Barrier

One of the requirements for the green building certification is to protect the main residence from the fumes and gases of the garage- Car exhaust is not exactly healthy. Build it Green thus requires to either detach the garage from the house or- as in our case- provide an air barrier that prevents the spread of VOCs and other toxic gases to the residence. So we bought the heaviest plastic sheeting available and started to staple it to the studs of the garage walls and taped the joints prior to the gyp board going up. The picture shows Grit taping joints at the ceiling.

And now to the stuffing...

The exterior has been fully wrapped- with standard black building paper for the stucco areas and the orange vaproshield for the areas to receive the rainscreen facade. With everything now waterproofed, Abe started to insulate the exterior walls- He's using Knauff Eco Batts, a formaldehyde free fiberglass insulation product, made from recycled glass and with formaldehyde free resins. The product is as good as fiberglass insulation can get- It's not quite as good as Ultratouch, the recycled cotton insulation though, but this super-green product is also 3 times the price of fiberglass insulation and therefore way out of our reach.
Parallel to that, the stucco sub is installing channel and control screeds on the exterior and we hopefully will have the building lathed by the end of next week.

Paper or Plastic?

We’ve moved on to the next step- to wrap the house in building paper and to install the required screeds and flashings. There are a myriad of different products on the market- each promising to be better than the other one. There’s Tyvek and Typar, which both are in an advertising war against each other (the concept is pretty interesting and we had looked into Tyvek for a bit (Tyvek has a pretty high UV resistance which allows it to be exposed to the sun for an extended period of time)- but since the code requires a 2-layer weather resistive barrier system- so we would have had to have either 2 layers of Tyvek or one layer of Tyvek and one layer of regular paper. We finally decided to go with paper and not plastic- Since the code requires that 2 layers of building paper are being used, some manufacturers offer paper with a double-thickness (theoretically the strength of 2 layers of paper, but the reason why 2 separate sheets should be used lies elsewhere- The tiny gap between the 2 layers functions as a drainage plain- a micro channel where water, which manages to get through the first layer can drain vertically down to the weep screed. Sound pretty simple- and yet, you see the double-layer strength paper being used all the time. The photo shows the South- west corner of the building being wrapped already.

Making it look like one

One of the downsides of wood frame construction without using structural steel is the reduced spanning capability of the naturally grown material- While steel can create exciting cantilevers, wood does allow for some, but needs more regular support through vertical members. This becomes in particular evident in the many corner windows that we have in our project. We decided to incoroporate those vertical members into the aesthetics of the openings- making them part of the window, rather than having them stand out as a cloumn by their own. We achieved this by cladding the posts in the same material as the windows- class 1 clear anodized aluminum. We think this looks great- but see for yourself on the photo above. It shows the corner window of the 3rd bedroom towards the street (see also on the street view rendering above).