Step 12 – Wall Sheathing

With the roof underlay on, the structure is now safe from direct rain, but there is a ton of wind here in Point Roberts thanks to the proximity to the ocean, so wind blown rain is still a threat. Installing the wall sheathing will solve that problem, at least for the short term.

Many builders apply the wall sheathing to the studs before they even stand the wall up. This would have required me to rent some heavy equipment, so I decided against it. Another good thing about installing the sheathing now as opposed to earlier in the build, is that I was able to wait until I was sure that the interior of the structure was nice and dry. If I had attached it earlier before the roof was on, rain would have soaked everything from above and then the sheathing would have blocked all the wind from drying everything out.

The wall sheathing serves several very important functions besides acting as a blocker to wind blown rain. Most importantly, it provides the necessary wall bracing to adhere to building codes.  Second, it functions as the integral part of the outer air barrier, which is crucial to achieving net-zero.  Last, it will provide nailing support for the exterior rigid insulation.

Sheathing the walls solo, like the floor and roof sheathing, required a few creative bits of ingenuity.  The 4 foot high and 8 foot long sheets weigh a little over 45 pounds, and the top row of sheathing must be installed 20 feet up in the air.  Just carrying one of these sheets is cumbersome, let alone figuring out how to hold it in place and nail it with only 2 hands.  On top of that, I had to figure out how to apply a bead of caulk around the edges of the sheets and at window openings, and keep in mind that some of this would need to be done on a ladder.  The task at hand was quite daunting, but after thinking it over for a bit I was able to come up with some techniques that worked surprisingly well!

Before the sheets could be installed I had to attach some blocking halfway up each wall, in between all the studs.  This is required for wall bracing to ensure the sheathing is fully attached to the structure.  I had several extra 2×6 studs from a minor mistake I had made when ordering the framing lumber, so I ripped them in half and then cut them to fit between the studs.  Each block was end nailed to the stud on one side, and then toe-nailed on the other side.

Marking out windows and studs before installing the sheet made nailing a lot easier

Attaching the first row of sheathing was obviously the easiest.  I snapped a chalk line halfway up the bottom plate and then sank a few 16d nails just below it so that if I rested the board on the nails, the bottom of the board would line up with the chalk line.  Next, I grabbed a sheet of plywood from my stack and drew a line every 2 feet.  This would make knowing where the studs were for nailing much easier.  Next, I grabbed my caulking gun and used Dynaflex 230 to lay a bead of caulk along the top of the bottom plate, the bottom of the blocking, and the two studs where the ends of the sheet would be.  I also caulked all the way around any window openings that would be under the sheet I was installing.  After that it was a simple matter of lifting the sheet onto the nails at an angle so the top of the sheet wouldn’t smear the caulk, then positioning it precisely, and last pushing it into the wall and nailing it down.  Each sheet was nailed every 6″ along the edges and every 12″ on the lines I had drawn.

Plenty of caulk along the edges of each board and around windows will ensure an airtight barrier

Installing the next row wasn’t a whole lot more difficult.  I sank 16d nails on each stud just over the top of the previous row of sheathing.  This will leave a small gap between the rows which will allow for expansion due to heat and moisture.  I marked lines every 2 feet to line up with the studs and caulked just as I had with the sheets in the first row.  Then I hoisted the sheet up on top of my homemade scaffolding and then used a ladder to get myself up on the scaffolding as well.  From here I could install the sheet just like the first row by angling it onto the nails, positioning, and then pushing it to the wall and nailing it down.

The third row got a little more tricky.  I installed more blocking, snapped a line marking where the top row of sheathing should go, marked lines every 2 feet on the sheet, and caulked.  Then, from the second floor inside the house, I clamped my winch to the top half of the stud that would lie in the middle of the sheet, and used a c-clamp to attach the belt to the sheet of plywood.  Then I cranked up the winch until the sheet was at the right height, positioned it from inside the house on the second floor, and reached around with my nail gun to tack it down.  Then I removed the c-clamp, went downstairs, and climbed a ladder to finish nailing down the panel.

On the gable ends, I was able to install the final row just like the third row by simply moving the winch up to the gable end truss and attaching it there.  On the other two sides I had nothing to clamp the winch too!  After trying in vain for quite some time figuring out how to do it on my own, I realized this might be one of the times I needed to call a friend over.  I drilled holes in a couple of scrap blocks and nailed them to the frieze blocks, and ran one of my nail stakes left over from the foundation through the holes.  Then I ran a rope around the nail stake so both ends dangled down at the bottom of the house.  I attached one end of the rope to a c-clamp around the plywood, and left the other end dangling.

Here you can see the bar we used to help us lift the last of the sheets into place

When my friend arrived, I caulked the area where the sheet would go and then he stood on the second story and hoisted up on the rope while I simultaneously pulled in the slack at the bottom.  Once the sheet had reached the top, I nailed a second stake into the ground and tied off the rope so we could both let go and the board would stay in place.  At that point I climbed the ladder with my nailgun and gave him instructions on which way to nudge it so it was perfectly positioned and then nailed it down.

 

It may look pretty boring now, but the interior is protected from the elements!  The exterior of the plywood sheathing will definitely still get wet, but the water won’t leak through and the inside will stay nice and dry.  I will wait until it gets a little warmer in a couple months so I can be sure that the outside of the house is completely dried out, then I will install the exterior foam, water barrier, furring strips, windows, etc.  In the meantime, it is nice and dry inside and I will be starting on the plumbing!

A huge thank you to my friend PJ for his help, both with coming up with the idea on attaching the bar to the house and for his strength helping to hoist the sheets!

 

Step 11d – Inspection, Bargeboard, and Gable Overhangs

I’m tantalizingly close to reaching that glorious step where rain will no longer be able to harm the OSB roof sheathing or subfloor but a few key steps remain.  Most importantly, there is currently no roof sheathing on the gable end overhangs.  As you can see in the pictures, I only installed the sheathing up to the gable end trusses instead of extending it out to the ends of the lookouts, which is where the roof will eventually end.  The reason for this is that the bottom of the gable end overhang sheathing is going to be visible from below, and the OSB I used for roof sheathing has a very cheap look to it and can tend to flake off when exposed to the elements.  Plywood looks ten times better and will hold up much better to the elements, so it’s worth making the transition from the OSB to plywood just for those gable end overhangs.  This part of the roof isn’t structural however, so it wasn’t part of the roof sheathing inspection I passed yesterday.  The plywood is only to add a nice aesthetic touch.

The other item that needs to be installed before adding the roof underlay is the bargeboard.  Made of the same primed, textured wood as the fascia, the bargeboard will attach to the fascia and run along the edge of the lookouts up to the ridge.  Once it is in place, the roof will be entirely surrounded by this finished wood.  Before nailing it on, I climbed up the roof and measured the lookouts, recording the length of the shortest lookout on each side (they varied up to 3/8″).

I grabbed what was left of the primed, textured, wood and beveled the top edge at 22.6 degrees on each side, to form the shape you see below.  I also cut each piece to the length I had recorded for the side it would be attached to.  I toenailed these pieces on to each end of the roof ridge, and then snapped a chalk line across the lookouts, holding one end of the line on the edge of the ridge pieces, and the other just grazing the end of the shortest lookout.  This gave me a visual as to which of the lookouts needed to be trimmed just a bit so they would all be even.  After cutting them down with a circular saw, I mitered one end of the bargeboard and brought it up to the roof.  I eased it over the edge and lined up the top side with the tops of the lookouts, clamping it in place.  Next, I marked the other end of the bargeboard where it crossed the center of the ridge piece and cut it along this line, then nailed it to the ends of the lookouts using galvanized nails (as these nails will be exposed to the elements).

With the bargeboard in place, I ripped a sheet of plywood in half the long way, and used my winch and rails to reel the two pieces up to the top of the roof.  I lined one end up so it was about a 1/4″ from the edge of the bargeboard and tacked it down to the lookouts.  I then ran my circular saw along the opposite edge of the plywood deep enough so it would cut through the OSB sheathing.  This trimmed off about 3/4″ of the OSB sheathing, exposing half of the gable end truss to support the plywood.  This was important so I would have something to nail the plywood into.  I cut the second piece of plywood so it lined up over the fascia the same distance as the OSB sheathing, and then thoroughly nailed the plywood to the gable end truss, lookouts, and bargeboard.

Here you can see the process in action with step 1 trimming the lookouts on the right side, step 2 placing the bargeboard on the left side, and then step 3 adding the plywood towards the center of the pic

As I’ve said before, there’s nothing quite like working on a roof when it’s a beautiful day!

Step 11c – Install Roof Sheathing

I had been waiting for today for almost a month!  It has been so frustrating to watch the second story OSB subfloor get wet day after day, but today I took a big step towards getting a roof over it as I installed the first row of roof sheathing.  With all the inclement weather, I had spent plenty of time figuring out how to get the roof sheathing installed as safely and efficiently as possible.  Carrying a 4 foot by 8 foot sheet of OSB is hard enough on the ground, so the thought of bringing it 20 feet up a ladder didn’t sit very well with me.  My solution was to buy a cheap winch online and build some “rails” so I could simply stand on the trusses and crank up the OSB like I was reeling in a fish.

It worked like a charm!  The webbing that came with the winch wasn’t long enough but I had some extra rope that worked just fine.  Before I started reeling the sheathing up to the roof I used a chalk reel to snap a line 4 feet up from the fascia.  The goal is to have the top edge of the OSB sheathing line up directly over the top of the fascia.  With that done I brought up the first panel and matched it up with my chalk line.  Just like the subfloor, the roof sheathing must be nailed to the trusses every 12″ on the inside parts of the panel and every 6″ on the edges.  I used my tape measure to ensure that each truss was on layout 2 feet center to center before nailing down the OSB. Once the sheathing is nailed down the trusses aren’t going to go anywhere so this was my last chance to make sure they were nice and straight.

Before installing the next row of panels, I installed an ‘H-Clip’ roughly halfway between each of the trusses, as shown above.  These will ensure that there is enough space left between the panels to allow them to expand and contract due to heat and moisture.

Here is a more closeup look of the clip.  Once they were installed I repeated the steps on the next layer of sheathing.  When I had reached the top layer, I measured to the top of the ridge of the roof and ripped the panel down to size so it would end at the ridge line.  I moved in six inches from the edge, and then ripped it down an additional 3 inches.  This will leave a 3″ gap on each side at the top of the roof sheathing for the ridge vent.  The ridge vent will work together with the baffles to properly aerate the attic and dry out any moisture that finds its way in.  As I will show later when I start on the shingles, the gap for the ridge vent will be covered with a material that will allow air, but not moisture, to go through it.  I am currently only halfway through the roof sheathing, but hope to get the rest of it done tomorrow.  The building inspector only comes into town on Tuesdays so if I don’t finish tomorrow I will have to wait an entire week before starting the roof.  The inspector must check up on the roof sheathing, specifically proper nailing of the roof sheathing, before I can start on the shingles.

Once the other half of the sheathing is complete, I can remove the vertical 2x4s from the gable end.

Step 11b – Lookouts and Fascia

Two other items that need to be installed before adding the sheathing are the lookouts, fascia, and subfascia.  These elements will work together to add some flair to the edge of the roof line.  The lookouts run along the gable ends of the house, and will not only give a nice look to the trim, but will also support the outer edge of the roof, which will run a couple feet beyond the walls of the house.  These overhangs help to keep rain away from the walls, and also provide some shade for the windows when the sun is high in the sky.  

The lookouts consist of 2×6 lumber cut just under 4 feet long, and are installed like cantilevers.  One end is nailed one truss inside from the gable end truss.  The gable end truss is then notched so the 2×6 sits inside of it.  The other end is left loose as you can see above, and will eventually attach to the bargeboard.  This step is easier once the roof sheathing is on.

You should be able to visualize how the cantilever works in the picture above as all of the weight placed on the outer edge of the lookout will actually create an uplifting force on the inside truss.   This force will be nicely balanced by the weight of the roof.  You can also see why the lookouts need to be installed before the roof sheathing, as half of them will be covered up with the sheathing.

The subfascia attaches to the end of the truss tails.  Not only will I be using it to line up the ends of the trusses and ensure they are nice and straight, I will also use it as a support for the fascia, which I will describe next, and to provide nailing for the soffit, which won’t be added until a few more months in the build have passed.  Like the frieze blocks, the top of the subfascia is beveled to match the slope of the roof.

Straightening the trusses out sometimes requires a significant amount of force, Imagine yourself 20 feet up in the air, leaning out over the edge of the wall, trying to hold an 8 pound nailgun with one hand and applying a ton of force with the other hand… Not a pretty thought, is it?  Clamps give me an extra pair of hands so I don’t need to put myself in those kinds of positions.  Above you can see how I used two of them – one to move the truss slightly horizontally and another to move it vertically.

A couple makeshift brackets help support the subfascia while I’m getting it ready to nail in.  The main part of it was a 20 foot long 2×6 board, which weighs in at close to 50lbs.  It isn’t something you really want to carry up a 20 foot ladder!  With the brackets, I was able to pull the board up through the trusses and then ease it over the edge of the truss tails until it was lying on the brackets.  Then I would climb up the ladder to nail it in.  Once I was finished I pulled out the nails holding the bracket to the wall and set it to the side until the next time I need it.

 

The final step before attaching the sheathing is the fascia.  The fascia is pre-primed and textured since it is one of the first pieces we are adding to the house that will still be visible when construction is completed.  As you can see, it attaches directly to the subfascia.

Just like the previous parts I described, the top of the fascia is beveled to match the slope of the roof.  The edge of the roof sheathing will sit on top of the fascia.  When the gutters are added, they will run around the fascia and partially conceal it.

 

Step 11a – Frieze Blocks and Baffles

Working on the roof definitely has its perks when it comes to sunset!  Doesn’t show up as well in the picture but I had a beautiful view of a snow covered Mt. Baker there.  So when I ordered the roof trusses, I had specified that I wanted a 15″ energy heel.  This feature ensures that the attic insulation will maintain it’s full strength all the way to the edge of the wall.  I will be using blown-in cellulose insulation in the attic and to achieve my desired strength of R-60 I will need about 16.5″ of insulation (blown cellulose has an r-value of about 3.7 per inch)  A standard truss would slope all the way down to the top plate, leaving only the width of the truss chord between the ceiling and the roof.  For a net-zero home this is unacceptable.  So before we can apply the roof sheathing, the sides of the walls need to be built up to the same level as the roof, otherwise the cellulose would just fall out after we blew it in.

 

The pieces used to build up the wall are called frieze blocks.  If you look closely, you can see how I had to add in a layer of plywood to ensure that the blocks were tall enough.  In addition, I beveled the top edge of each block so that it would match the slope of the trusses.  Any place in the house where insulation exists, it becomes very important to have an airtight seal all around it.  The beveled edge will make it much easier to air seal the frieze block to the trusses on the sides, and to the roof sheathing on top.

 

You might notice that every third frieze block is a few inches shorter than the others.  The spaces there will be used for baffles.

A baffle is used to ventilate the attic.  Even with a perfectly installed roof and airtight seals all around the insulation, moisture has a knack of finding its way into pretty much anyplace you don’t want it to be.  The most effective way to remove this unwanted moisture that could potentially lead to rot and mold is to use moving air.  The air will enter the attic through the baffle and warm slightly, causing it to rise and eventually exit through the ridge vent at the peak of the roof.  As the air completes this journey, it will pick up any moisture that exists in the attic.  As you can see below, the baffle is more than just an opening through the wall of frieze blocks.  It is actually more like an air tunnel that runs over the top of the insulation.  Again, recall that it is extremely important to ensure no moving air comes into contact with the insulation. 

If you can imagine the roof sheathing going on over the top of this baffle, it will create a 2 inch wide air tunnel through the attic between the two layers of wood.  Below you can get a good look at the frieze block from the bottom.  Several months from now, practically this entire area you see will be filled with energy saving insulation.  You can also see where I added hurricane ties to lock the trusses to the top plates of the walls.

 

 

 

 

 

 

 

Step 11 – Install the Roof

The first part of building the roof is to “roll trusses”.  Although some old fashioned builders prefer to frame their roofs one piece of lumber at a time, when building solo it can be dangerous to handle large roof framing members when you are two stories up in the air.  Most modern builders order the roof trusses premade and then have them placed on their sides on top of the house with a crane.  Then all you have to do is to drag each truss to it’s proper location and roll it upright to a vertical position.

Before they arrived I made sure to plumb and line the second story walls. This was relatively easy because with the floor already in, I knew the first story was locked in very tightly. This meant I could use it to brace the second, which I did with the plumb bob and 20’ 2x4s just like I did on the first.  On a side note, if anyone ever tells you that it’s impossible to carry 20′ 2x4s in a Ford F-150 without a $300 rack you can show them this as proof they are wrong.

The trusses arrived on a long flatbed, and the driver used a crane to hoist them 20’ up to the top of the second story wall.  They came in two stacks so I had him lay one down in the middle of the house and the other standing up at the other end. I used some long vertical 2x4s to support the vertical set so they wouldn’t fall over the side of the house.   I was fortunate to have my friends Michael and PJ helping me as the 24’ long, 5’ high trusses are pretty heavy for a one man operation.

Here you can see the three long vertical 2x4s and a small clamp at the bottom that is holding the trusses tightly against them

We started with the stack that was lying down.  We grabbed the gable end truss and slid it down to the other end of the house where we slowly, carefully stood it up against vertical 2x4s just like the ones at the other end.  We nailed it to the top plate flush with the end, and then nailed a small 2×4 block to prevent the truss from falling back down. I had precut these pieces, which are called bird blocks, to 22 7/16” so they would fit snugly in the spaces between the trusses. We slid the next truss down and lined it up against the bird blocks, then used a 2×4 as a pole to push the truss up into its vertical position.  At that point we would end nail it into the bird blocks, and toenail it into the top plate.  Below you can see all 3 pieces together, with the trusses resting on the top plate, and the bird block fitting in between them.

We continued to repeat this process until we had rolled all the trusses in the first stack.  At that time, we ran a few 1×4 boards along the inside of the top chords to ensure they were spaced properly.  They also help to add lateral strength to the trusses to prevent them from rolling back over on their sides.  You can see them as the two darker lines near the center of the photo.

The second half of the trusses were installed in much the same manner, but was a good deal easier since the crane had already placed them standing up.  For these trusses, I installed the 1x4s first, and then used them as rails to ensure that the trusses would remain upright as we slid them into position one at a time.  If you can imagine how the rings on a shower curtain slide across the curtain rod, it might help you visualize the trusses sliding along the 1×4 rails.

If I haven’t made it clear before, building a house can be quite a surreal experience.  Here I am standing on top of a second story wall taking the above picture and marveling at what a phenomenal day it is while most of the rest of the world is hard at work, slaving away at jobs they don’t like to slowly chip away at 30 year mortgages.  If they only knew they could build a beautiful net zero home in such a serene suburb of a major city for less than 200k.  Oh, and not just any city – Vancouver was the only North American city to crack a European-dominated top 10 quality of living ranking of global cities.  (Mercer – 2017)

It looks a little messy with all the long 2x4s sticking up at the top and diagonally bracing the walls but this is the complete skeleton of the house!

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 9b – Install the Subfloor

Solving small problems is a huge part of building.  I’ve always enjoyed crossword puzzles and the like, so I shouldn’t be at all surprised that I am enjoying building the house so much.  Today’s problem was how to lift 24 sheets of OSB panels 11 feet up in the air.  (2 feet of foundation + 8 feet of wall + 1 foot of joists = 11)  You see, each panel is 4 feet wide and 8 feet long, and weighs 59 pounds, so not only are they heavy, but it is difficult just to get your arms around one.  My solution was to build a small section of scaffolding about 6 feet long and 5 feet high.  Then I would carry the OSB over to the scaffolding while holding it just like this guy is.

Turning it so the shorter side is down, I then lifted it up onto the scaffolding

Then I would climb up to the top, grab the end of it and pull it the rest of the way up.  This was easy once I had a couple of them already up there to stand on but for the first ones I had to just stand on a couple of 2×6 boards that I had laid out perpendicular across the joists.  Have I mentioned that building a house is a great way to face your fear of heights?  I lifted every single one of the 24 boards up to the top of the wall in this same manner.  The first row you attach is the most important one to be straight because all the other rows will interlock with it.  I used my chalk reel to snap a line 4 feet in from the edge to ensure that I got it just right.  Next, I applied a liberal bead of elastomeric construction adhesive to the top of the joists.

PL400 is highly recommended for subfloor gluing

I set the board down over the joists so it lined up with the one corner of the house and ensured that the other end was halfway onto a joist.  This is the reason why I lined the joists up 24″ on center.  The 8′ long panel spans 4 joists and on the outer joists it leaves enough space to share the joist with another panel.  Once the panel is perfectly lined up the code calls for it to be nailed with 8d common nails every 6″ on the edges and every 12″ in the middle areas where a joist runs under it.  The boards are marked out so you can easily find the spots where these nails should go if the joists were lined up correctly.  If you look closely you can see them…

You can also see how I left a small gap in between each board to allow for expansion due to heat and/or moisture.  Four of these 8′ long panels were enough to run down the length of the house.  For the next row, I cut a panel in half.  Staggering the seams in this way adds strength to the floor.  With the first two rows complete you can see how the staggering seams look.  Notice how I positioned the other boards so I could walk around as I worked.

When I got to the row above the blocking I used a sander to make sure that none of the blocks stuck up above the joists.  I also measured out where pipes would go through so I could easily find them later.  One of the pipe fittings stuck up above the joists so I had to cut a hole for it in the OSB.

There’s the pipe I cut out a hole for on the right side and if you look closely you can see where I marked out where the other pipe will penetrate the flooring as it heads up to the roof vent

Luckily I thought ahead a little bit and before I got to the last panel I cut out a hole for the stairway opening.  Otherwise I wouldn’t have been able to get back down!  The opening will eventually be much larger but for safety reasons I left it just big enough to allow for comfortable access.  I marked a warning on the areas that will eventually be cut out because there aren’t any joists underneath.  The OSB floorboards are strong but without a joist underneath they could easily break.

The last step was to run a circular saw all the way around the perimeter to remove any protrusions.  Because of the small gap between each board there was about a 1/4 inch left around the edges.  That and the stairway opening was the only waste I had.  This is very rare in today’s average construction job as the house plans usually call for a bunch of details and angles in the floor.  Contractors cut panels in all sorts of ways as needed and then discard what they don’t use, which can be a substantial amount.  This is one of the benefits of designing a house yourself.  I specifically designed the house with dimensions divisible by 4 feet for this very reason.

Step 9a – Install Blocking and Plumbing

Before the subfloor can be nailed onto the joists, small sections of 2×12 called “blocking” must be installed.  Together with the rim joists they ensure that the floor joists won’t roll onto their flat sides where they can easily bend.  The blocking is placed along the top of the interior bearing wall at the exact place where the two floor joist spans meet and nailed perpendicularly between them.   I kept all the plumbing of the house on interior walls so I wouldn’t take any precious space away from my insulation inside the exterior walls.  My interior bearing wall being the major wall on the first floor, this meant that it had a significant amount of plumbing running through it.  The plumbing runs through the middle of the wall, and all of the DWV pipes must be vented vertically through the roof.  These pipes want to go through the middle of the interior bearing wall and exit right into the middle of my blocking!  My solution was to simply install a double set of blocking with the pipes in the middle.

Here you see the normal blocking at the outer edges of the pic and the modified blocking in the middle. The 2×6 boards at the bottom of the pic are for me to walk on until the floorboards are installed! Note how the joists from each exterior wall meet in the middle at this point.

In addition, I had planned for some of these pipes to run horizontally in the space between the floor joists.  For example, the washing machine is on the second floor, but the space I want to put it in doesn’t have a wall below it on the first floor.  If I didn’t run the pipe horizontally I would have a pipe for the dirty clothes water running through the center of the guest bedroom!  So this horizontal run would need to make a turn through the blocking so it would run in the space between the floor joists.

The pipe on the left makes a 90 degree turn to run between the floor joists while the one on the left goes straight through the blocking and will continue through the 2nd floor walls and out through the roof

 

 

All of my planning really paid off because some of the runs of ABS pipe were required to have cleanouts.  If I hadn’t installed them before running the vertical pipe up through the blocking it would have been a pain to do later.  The one you see below will be covered with a bench seat at the dining room table.  In case of a plumbing emergency the cushion can be taken off the seat and a hinged panel will provide access to the cleanout.

For a contractor, calling the plumber out before the entire house is framed is unusual.  I’m sure they would have been able to come up with a solution without breaking their routine, but I’m also pretty sure it wouldn’t have been as neat and efficient as my solution.  For me, it was very easy to stop framing for half the day and work on some plumbing so that I could finish with the blocking.  Yet another great example of the flaws in building a house with contractors…

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Step 9 – Frame the Floor

Flooring is pretty basic, and if you’ve ever noticed how a deck is built then you have the gist of it.  Long boards called joists are laid out parallel with each other and on their sides so they won’t bend easily.  4×8 sheets of plywood or OSB are laid out over the top of the joists to create a flat, sturdy surface.  The joists are supported by some of the first floor walls.  As I mentioned before, one of my interior walls is a load bearing wall, so it will be used to transfer half the weight of the second floor of the house down to the ground .  The 2nd floor interior walls will rest on the subfloor, which will in turn rest on the floor joists.  Since the floor joists span all the way from the exterior walls to the interior bearing wall, they will need to handle a significant amount of the weight of the house, which they will then transfer to the exterior walls and the interior load bearing wall.  The pic below might help you visualize…

Notice how much weight is carried by the load-bearing wall in the middle

Proper joist sizes can easily be figured out from the IRC (International Residential Building Code) using a table in the same way you calculate header sizes.  For me, that meant looking at the part of the table that dealt with 24 inch joist spacing since that is what I’m using.  Then figure out what the greatest distance the joists will span is, which for me is just slightly over 14 feet.  Last, select a lumber option that supports a minimum span greater than this distance.  I decided to go with #2 2×12 Douglas Fir, which supports a span of up to 16’6″.  Going with an option suitable for a span larger than what I need will hopefully give me a less bouncy, less squeaky floor.

Lifting 16 foot 2×12’s 10 feet up in the air solo is a great workout.  After cutting each joist to length.  I lifted one side up in the air and rested it on the top of an exterior wall.  Next I moved a ladder near the interior bearing wall and lifted the other end of the joist up so I could rest it on the top of the ladder.  After climbing up a few rungs on the ladder, I had enough height where I could lift the joist from the top of the ladder to rest on the interior wall.  Just as with the wall framing, it was important to ensure that the crown of the lumber faced the sky.

The first joists I installed are called the rim joists.  These run on the top of the exterior walls perpendicular to the rest of the joists.  Above you can see the rim joist on the left side of the corner and the outermost floor joist on the right side.  Using rim joists ensures that there is a perimeter of joists all the way around the house even though the majority of the joists run in the same direction.  The rim joists are “toe-nailed” to the top plate, meaning that they are nailed diagonally.  Once the rim joists are up, the other joists are placed perpendicular between them and nailed to the rim joists, as well as toe-nailed to the exterior walls.

The opening for the stairway required a little bit of detail.  The code requires joists to be doubled all around the opening.  In addition, any time you are unable to rest a joist on a bearing wall, you must use steel joist hangers to carry the weight around to where it can reach a bearing wall.  The manufacturer of the hangers (in this case Simpson Strong-Tie) tells you what kind of nails you must use and what amount of weight the hanger is capable of carrying.