Step 10 – Frame the Second Floor

You can see how I’ve been trying to keep the OSB flooring dry with a tarp but with the walls going up it is difficult.  Luckily, I spent some extra money on Weyerhauser EdgeGold OSB subfloor and according to their reps they are perfectly fine to get wet for a few weeks as long as they are given time to dry out.

Framing the second floor is not a whole lot different from framing the first.  Whereas on the first floor, the sill plate was pressure treated lumber, this isn’t necessary on the second.  Also, the bottom plate was bolted to the concrete foundation on the first floor, but on the second we simply nail it to the rim joists as you can see below.

Before raising the exterior walls, I toe-nailed the inside edge of the bottom plate to the floor boards.  These nails help enure the wall stays in position and doesn’t fall off the house before it gets nailed into place.

After going up and down the ladder many times cutting pieces for the walls I decided it was time to build something permanent.  The finished house will have a large spiral staircase but it would get messed up pretty quickly during building (as well as annoying) so instead I just threw together a makeshift ladder from some scrap wood.

Whereas the first floor walls were pretty simple, things got slightly more complicated on the second floor with the master bathroom as it has walled off areas for the shower, toilet, and two walk-in closets.  Several of these walls are angled, and one of the master bedroom walls is actually curved! 

Creating an angled wall is pretty simple.  You can see I have two walls meeting at a 45 degree angle on both the left and right side of the picture.  All you do is miter both top plates and bottom plates at 22.5 degrees so that when they fit together they create a 45 degree angle.  You can see how the studs meet on the inside wall and the small gap on the outer wall will be covered with a metal corner bead under the drywall.

At the center of the pic above I actually have three walls coming together in the shape of a ‘Y’.  For these I mitered the two arm walls with 45 degrees and joined them to a straight wall.  When it came time to add the top plate I had to do cut a special piece to fit with a jigsaw.

To build the circular wall, I had some 3/4 inch plywood ready.  I created a makeshift compass to get the right radius for the wall and transfer it to the plywood.  Then I drew out a second radius exactly 3.5 inches smaller than the first for the inside of the wall plate.  Sandwiching two of these pieces together, I ended up with an equivalent to a ‘curved’ 2×4.

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The one thing about a curved wall is that it uses a lot of studs!  The far side of the wall will curve right around the spiral staircase when it is installed. (I haven’t cut the opening completely yet for safety)

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Step 8b – Frame the Interior Walls

In my last post, I discussed how using advanced framing would help me lower my heating bill by creating more space for insulation.  However, insulating a house is just one of the ways to reduce the amount of energy needed to heat (or cool) a house.  No matter how much insulation I put in the house, if I don’t control the air that is allowed to flow through the walls  it will be impossible to control the temperature.

Air is able to transfer heat using convection.  This is great when you are using a furnace or a heat pump to blow nice hot air into the house during the winter, but in many houses, that air is allowed to escape back outside through tiny cracks and crevices all throughout the house.  According to the US Dept of Energy, up to 30% of heating and cooling cost is due to lack of air sealing.  One of the places where air can escape is in the tiny gap between the sill plates of the walls and the concrete foundation.  While I did place a sheet of sill gasket in that area, that was only to prevent water from wicking up the concrete and into the walls.  The sill gasket is air permeable, meaning air can pass through it.  I needed to add an additional layer that was air impermeable to fill the gap, and some all-weather caulk fit the bill nicely.

Countless houses leave this crucial step for later, or skip it altogether.  The best time to do it is now, though, because after I frame the interior walls it will be nearly impossible to caulk the spaces where they connect to the exteriors.

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Another technique I will be utilizing to control air movement is using “continuous drywall”.  This means that the drywall will slide in behind the wall framing for the interior walls, resulting in fewer joints in the drywall and thus fewer opportunities for air infiltration.  Each of these small details contributes just a little more energy savings and helps to get the house to achieving net-zero.  Above you can see a pic of an intersecting wall with continuous drywall, which is the method I will be using, and below is a traditional method that the majority of builders use.

 

 

 

 

 

 

The drywall won’t be installed until later in the build, at least until the roof and siding are installed.  Drywall doesn’t perform very well when it gets wet.  This means I will need to leave a gap in between the exterior walls and any interior walls that run into it.  I cut small scrap pieces so they were 3/4″ thick and used them as spacers to ensure the gap was sufficient.  Even though the drywall is only 1/2″ thick the extra 1/4″ will allow me to slide it in the gap without damaging it.  I used the spacers at both the bottom of the wall and at the top as you can see below.

You can also see the line of caulking that follows the entire perimeter of the house

Splice plates are used to hold the top of the wall in place

I used standard framing instead of advanced framing for the interior walls since they don’t require any extra room for insulation.  This meant spacing the studs at 16″ on center instead of 24″ like I did with the exterior walls, and capping the studs with a double top plate instead of a single.  Additionally, I used 2×4’s to frame most of the interior walls instead of the 2×6’s I used on the exterior.  I did use 2×6’s on several of the interior walls that contained large plumbing pipes.  This will give me a little more room to play with as some of the pipes are over 3″ in diameter and the 2×4’s are only 3.5″ wide.  Beyond that, framing the interior walls is just the same as the exterior.  Mark the stud locations on the top and bottom plates and then nail them in.  A few details were needed for bedroom and bathroom doors as well as intersecting walls but overall it is a pretty simple process.  The second top plate is added on after the walls are up and is staggered in a way that ties all the walls together as you can see below.

 

Step 8a – Utilize Advanced Framing Techniques

To an experienced framer, the work I have completed over the last couple of days would seem wrong.  It is quite possible they would never have seen a house framed the way that I am framing mine.  A few might even claim that I am violating building codes in not following “standard practice”.  The fact is, I am utilizing a method of framing created in the 1970s in a collaboration between the U.S. Deparment of Housing and Urban Development and the National Association of Home Builders Research Foundation.  Their goal was to reduce the amount of wood used in construction, not only to save the lumber, but more importantly, to create more space for insulation and save on energy usage.  All of these small changes work to ensure the house will be net-zero!

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As you can see above, in traditional framing you have a single sill plate at the bottom of the wall connected to a series of studs spaced 14 1/2″ apart from each other (16″ on center) which are then connected to two top plates sandwiched together.  Additional shorter studs called “jack studs” are used to support headers above window and door openings.  Even more studs are used to anchor interior walls to the exterior.  All of the wood used are 2x4s, leaving 3 1/2″ of space between the studs for insulation.

In advanced framing, on the other hand, only a single top plate is used, studs are spaced 22 1/2″ apart (24″ O.C.), and metal “header hangers” are used instead of the jack studs.  On “gable end” walls, no headers are needed at all! (see below) “Ladder framing” is used to anchor interior walls and 2×6 lumber is used, leaving 5 1/2″ of space for insulation (obviously that’s the part of the wall that looks like a ladder in the pic)

The advanced framing system is cheaper because it uses 5% to 10% less lumber, and it is faster because it uses 30% fewer boards (although they are a bit bigger and heavier). More importantly, every single year more money is saved on energy costs because over 60% more insulation can be filled in.

This is a gable end wall, meaning it will extend all the way to the peak of the roof without slanting. Because of this, you can see I don’t have to use headers above the windows. (And yes, that is just a very light dusting of snow)

Okay, so what’s the catch?  If advanced framing was added to the building code over 40 years ago, is cheaper and faster, and reduces the energy bill every single month, then why isn’t it standard operating procedure for builders?  How could I possibly be telling you that most builders don’t even know about it?  While I could devote several pages answering that very question, I’ll do my best to sum it up quickly.  Building a house is difficult.  There are very few people who have the knowledge to do it all themselves and I may very well fall flat on my face in trying.  For me, that challenge is exciting, even if it is frustrating at times.  Because of this fact, the vast majority of houses are built by a massive team of “contractors” that under normal circumstances communicate very little with each other, if at all.  These tradesman are managed by a “general contractor” who uses building plans that were probably drawn up by an architect and edited by an engineer.  Although I was able to sum up the advanced framing techniques in a couple sentences, the small changes affect every single one of these workers.

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The architect and the engineer must design the house from the very beginning so the floor joists and studs stack up within an inch of each stud (see pic above)  This puts a sort of limiting factor on the architect in regards to wall lengths and window placements that many are resistant to.  Next, the general contractor must be open to training the contractors under him because many of them will be unaccustomed to the framing.  The framing crew will be working with a different length of wood due to the single top plate, and have to frame completely differently than they are used to.  The electrician has fewer studs to attach electrical boxes to.  The drywall crew has fewer studs to nail the drywall to and may have to hang it differently.  The small changes ripple right on down the line and affect every single person that works on the house.  As contractors are paid by the job and not by the hour, they aren’t too keen on taking time to learn this new technique.  The fewer that learn it, the fewer that are available to teach it, and the cycle continues…

As I’m building solo, I have none of these issues.  I designed the house myself from the very beginning with advanced framing in mind.  Thanks to my mentor, who introduced me to advanced framing, I’ve never built any other way.  I saved money on lumber and nails.  I saved time with fewer studs to nail together.  I saved trees because of using less lumber (I’ll be using dense packed cellulose in the spaces where the studs would have been which is made of mostly recycled newspaper and denim).  I will save money on my energy bill each month (or be able to use a smaller solar array).  I even save time building because with the larger spacing between studs I can jump in an out of the house anywhere instead of using a doorway.  If you really want to save sustainably, advanced framing is the way to go.