Back in November we had sheer braced the knee wall that spanned the front of the house. Tonight’s project was to add sheer bracing to the south rear knee wall. (The dormer divides the rear knee wall into two sections.)

Basically, it was much the same as in November, except we didn’t have to jack up anything (the span was shorter) and we didn’t add a plastic temporary ceiling. Maneuvering big sheets of OSB from a ladder is never fun. I’ll be glad when we have the last section of this done.

Part of the charm of our run-down old 1937 farm house is in its exterior details. As we replace old windows with new windows, we have been very careful to match the original look with the new look. Our focus on the details extends to the original window trim.

On Monday the window that Lee installed back in February had its trim installed. We hired out this work because Lee hates ladders.

We used SPF [Spruce Pine Fir] engineered wood for the trim, as it is extremely stable and comes pre-finished. The window trim was actually assembled on the ground using pocket screws and then fastened into place after all the shingle siding was cut back sufficiently. The missing cedar shingle siding was then restored under the window.

Most of the new trim has the exact same dimensions as the original. The large butt-jointed boards on the sides and top are wrapped in a casing to create a reveal effect. The sill trim had to change slightly, as the original wood windows had an integrated sill that extended back under the sashes. Our new aluminum-clad windows have their own sill, so the trim adds a surface-applied “sill” made of 2×4 SPF with a beveled top surface. This sheds water and mirrors the sloped sill of the originals. We’ve decided that the new sill extends out a little too far, so Lee is going to plane it down a half inch or so before we primer everything.

This weekend the inner wall framing for the master bedroom was added. As a reminder, we are remodeling our house with double-wall construction. The outer and inner framed walls are separated by an air-tight layer of XPS foam. Last week we had finished up sealing the middle layer for the master bedroom. I am particularly excited about about having this inner wall framed because it means wiring, the last layer of insulation, and then drywall can be added. Maybe I should say I am really excited about the WIRING and DRYWALL aspect. Like pee my pants excited!

Our last post about our progress in super insulating the master bedroom left us with the first layer of R13 fiberglass insulation and the end wall sheathed in OSB as a structural upgrade.

Next up is the middle layer of insulation. This is comprised of pink XPS foam board which serves three roles. It increases the insulative value of the wall by an additional R10, it provides a thermal break between the outer walls and inner walls (since wood is a poor insulator, a lot of heat is lost through the studs that hold up typical walls), and it acts as an air barrier (when sealed properly). Most heat loss in modern homes is through unwanted air transfer via small holes in the construction. On the end wall, we attached the foam board directly over top of the OSB sheathing. To join foam panels, we applied two beads with a caulk gun: one bead of PL300 foam adhesive, and one bead of siliconized latex caulk.

On the knee walls, we nailed the panels up to the studs. We used the same 3″ cap nails that we’ve grown to hate from previous steps (because they bend so easily).

The junction between the angled and knee wall panels would be difficult to seal with caulk, so we used spray foam. Spray foam was also used to seal other large gaps and potential leak areas. It will eventually be used in the attic to seal the top plates of the inner walls to the foam layers. We trimmed back excess foam after it had dried so it would not interfere with later steps.

As a final insurance against air leaks, we taped the connections between the panels, floor, and ceiling using Tyvek tape (which is designed to bond to plastic/foam surfaces). The cap nail locations were also taped. This is really sticky tape, and should provide good insurance against cracks in the caulk which will form as temperature changes cause the foam panels to change dimension.

Our next step is to frame the inner wall which will hold wiring and plumbing. Then the inner walls will be insulated with wool batts. This will bring the ideal wall insulation value up to R33. (Not counting small insulation gains from other sources, such as the drywall and wood sheathing layers, nor the losses from thermal bridging through the stud framed wall layers.)

We haven’t posted about the inside of the house in a while, but that doesn’t mean we’ve given up. Slow progress is still being made on the future master bedroom. After the window was installed, I started on some structural details. This picture provides an overview:

The green boxes highlight straps. These are six 16 gauge metal straps that I added to connect the base of this wall to the top of the first floor. In the event of an earthquake, this will help hold the two levels of the house together. I added some doubled studs in the wall to provide more nailing surfaces around these straps, and added blocking at the middle point of the wall (highlighted in red). At the base of the wall, highlighted with a blue box, you can see insulation and more blocking. Our house has decidedly non-standard construction around this area (called the band joist), so this arrangement of insulation and blocking is probably unique to our scenario. With the straps in place, I caulked holes and then proceeded to add fiberglass insulation:

As I’ve mentioned before, our primary construction goal is a “super insulated house”. I still haven’t written up an explanation of the complete design, but suffice it say this fiberglass is the first of three layers of insulation that will comprise the final wall. With the fiberglass up, I then nailed up OSB panels:

The OSB adds shear strength to resist lateral forces from wind and earthquakes. The panels were staggered down the wall, and all edges were nailed off into blocking using 2.5″ ring shank nails. At the corners, nails connect these OSB sheets into the same studs that support the knee wall bracing.

Next up: Foam insulation

Lee took Monday afternoon off from work and got the upstairs window installed. This was the first window that we have ever done. I was very nervous about this whole process. I was sure we were either going to drop it off the second story as we were trying to install it or Lee was going to fall to his death. Thankfully neither of those things happened.

It was a slow process. Lee had been slowly prepping for it the week before he actually installed it. Then it would be raining and there was no way I wanted him on a ladder in the rain. Yes, I am paranoid. That and I know that Lee doesn’t really enjoy heights.

See this picture here really freaks me out. Lee hanging out a second story window trimming the wood shingles before we could install the window. Though somehow I was the one admonished to get back when I tried to hang out the window. That might have something to do with my accidental clumsiness… Even though I wasn’t feeling clumsy at that particular time.

We went ahead and took out the old sill plate as it looked pretty weathered. Lee added a new one. Then he added three spacers and put another two by four on that. We needed to raise the new window up by three inches to bring all the windows of this type to the same height.

Since we raised the window height and the replacement was a little taller too, that meant that we had to cut out a higher section above the window. Now that was a royal pain in the butt trying to sawzall though all those tongue and groove plank boards along with metal flashing. Lee’s arms may never recover.

We somehow managed to get everything square, flashed, caulked, nailed, straight, working, (yes that’s right, both parts of the double hung window actually work correctly) all with no accidents by either of us that required hospital stays. Lee hasn’t gotten the trim on the outside of the window done yet but hey, we’ll leave that for another day.

Up until two nights ago, there have been multiple direct paths between our interior living space and the outdoors. For some areas, such as the first floor ceilings (open to the eave vents) we’ve simply stapled up plastic to hold in the air. For the second floor, we are in the middle of actual retrofit work and have to take things in order.

So far, we’ve talked about installing the foam bypasses and the new double stud top plates on the angled portion of the second floor ceiling. The knee wall was also strengthened by adding shear bracing and we started insulating the knee wall with fiberglass. That step has now been completed as shown here:

Two bays aren’t insulated in that picture. The final bay, where the knee wall intersects the end wall, will be insulated after we add shear bracing to the end wall (yes, we’re bracing everything). The half bay that isn’t insulated will eventually be cut out to become our front attic access. Our house has four separate attic spaces that will be insulated with blown-in cellulose, and each needs their own seal-able access panel. We will try our best to disguise them in the final detail work.

At the back of the house, we in-filled the attic bays on either side of the dormer with foam, and then added OSB to the attic portion of the dormer sides. Both sides of the dormer also had two stud bays headered off. These are going to form built-in book cases on each side right next to the window seat by the dormer window. The backs of the bookcases will have concealed access panels to get into the attic space on each side. The attic portion of the dormer walls will be insulated with 4″ foam much later. For now, we’re just relying on the OSB and stapled in plastic to hold in the heat. Note that the headers are only half finished. I ran out of 2×6, and I also want to get some 1/2″ foam to make a laminated header to reduce thermal bridging.

The foam insulated bypasses had some gaps where things didn’t fit together real well, so we filled these with spray foam and then had to trim off the excess with a flush-cut saw. Spray foam is obnoxious to work with (and spendy), but it gets the job done and provides R-6 per inch.

Next, we started adding the “real” insulation for the angled ceiling areas. This is formed by 2″ thick 8′ foam panels that are cut to fit tightly against the double stud plate above and come down to the knee wall. The first step in installing these is to caulk more of the bypass gaps, and also apply a ring of caulk to each bypass panel to seal it to the next layer. If the bypass panels do not adhere tightly to the next layer, then cold air will infiltrate between the layers and we’ll lose the insulating value of the outer layer. I’m using only siliconized latex caulk which has a significantly longer life than the plain latex variety. The beads of blue in the photo are PL300 foam adhesive.

Once an area was caulked and adhesive applied, we held the foam panel in place and tacked it up with 3″ plastic cap roofing nails. Enough nails were applied to hold the layers together until the adhesives dried. Long term, these panels will also be held in place by the next layer of stud framing. I really hate these nails, as they bend at the slightest provocation.
.

After installing a panel, we caulked the seams against the roof and framing in preparation for the next layer. So far four panels are up, (32′ linear feet). The rest have to wait until the end walls are sheathed. The remaining gaps between the roof and the double studs were closed in with stapled plastic to hold in the heat. This is the first time our house has been “closed in”, but it didn’t appear to make a huge difference with temperatures dropping to 12° for the last few nights. This weekend we’re supposed to have a 40° night, so we look forward to making ourselves uncomfortably warm for the first time in months.

Next up: wood blocking, metal strapping, insulation, and sheathing for the end walls …

Anybody want to cheer with me? That is indeed what you think it is in the below picture. Lee has officially started on the knee wall insulating. Now before you all get too excited for me in my luxurious living conditions, let me tell you that it’s not as warm as it looks. I’m shivering as I type. It’s a start though. Lee has about 2/5th of the knee walls done right now. Somebody needs to complain to Lee to make him finally post where this is all going. Hmm, then again with him down at his computer mulling about writing the perfect post makes it so he’s not insulating…

Lee is putting shear bracing back into the house. This will help if the “big” earthquake that has been forecasted for Oregon actually happens, but also just makes the house sturdier. Lee has some plans on making our old house more earthquake ready along the way. This is one of them.

Today’s project was the knee wall: a 5 foot high wall that forms two sides of the second floor and supports the roof. Our knee walls all sit on beams that span open living space below. The plan is to add OSB panels using adhesives and nails which will permanently tie the beams and knee walls together. This does two things. It adds shear, to resist lateral forces from wind and earthquakes. It also creates a connected load path, to prevent an uplift earthquake from breaking the knee walls loose.

To start off, Lee jacked up the widest span by 1/4″ before adding bracing. This heads off future sagging.

The beam is slightly narrower than the knee wall, so he added 3/8″ plywood shims to create a coplanar surface. 8″ wide strips of plywood were glued to the beam using construction adhesive and attached with a few nails.

Once that was on, Lee applied polyurethane construction adhesive to the beam and 3.5′ up the knee wall studs for each 8′ sheet of OSB.

The OSB was lifted into place and attached using 2.5″ ring shank nails. Rink shank nails have tiny one-way barbs that make them easy to drive but hard to remove. A shear wall nailing schedule was used, with nails placed about every 4 to 5 inches.

Lee decided that he wanted more bracing, so he added 2′ strips of OSB at the top of the knee wall. The seams were staggered for greater rigidity.

Finally we sheeted more ceiling area in with plastic to help slow down the heat loss until we can get around to real insulation. Yes, that is a saw in my living room. I sure don’t miss Arizona, but I do miss my nicely put together house. I think the plastic ceiling complements my plastic curtains.

The foam bypasses discussed in a previous post are all installed, so we moved on to the next step: installing top plates for the double wall framing of the angled portion of the second floor ceiling. This is slightly out of order, but once these plates were installed we could add a temporary plastic sheet ceiling to try to retain some of the heat on the second floor (it was all escaping through the ridge vent and 32° nights are cold).

With this top plate in place, we can adhere 2″ foam panels to the angled wall portion, squeezed up into the gap between the plates and the rafters, and then start building the framing for the inner wall in this area. The inner wall will carry wiring for the second floor and some of the first floor front rooms, so getting it finished will put us in a better position to start electrical work. Hopefully a future post can clear up where all of this is going.