Putting Floors in the Ceiling

The tiny house was designed as an upside down boat. The ridge beam is the keel, the rafters are the frames, and the floors go in the ceiling!

Source: http://www.denmanmarine.com.au/images/Restoration_and_repair/teal/fitting_frames.jpg

Floors are the horizontal boards that connect the frames to the keel. They strengthen the hull and prevent wracking (twisting) and flexing. Tiny houses need this as they will be exposed to hurricane force winds while driving down the highway! I could not find the name of this piece of wood in house building, but I have heard of people complaining about the house twisting in high winds. These wooden floors should strengthen up the roof and the entire tiny house.

Installing the floors was rather straight forward. A length of 2x4 was cut and screwed to the rafters. If the roof were to try and lift, the floors would move upward and be stopped by the ridge beam. If the house were to twist, the triangulation of the floors, rafters, and ridge beam would resist the motion.

The floors are eventually going to be covered up when we insulate the inside and then cover the frames with interior siding, but for now, they can shine in the sun with all their structural glory!

Waiting for the Weather to Pass

A low pressure began to move in, so we covered the roof with a tarp to protect all the non-oiled wood from water damage. The clouds gave plenty of warning to the approaching front.

A thin veil of clouds came over the sky and as the day progressed, the clouds slowly became thicker and thicker. By the next morning, the rains had come and the tiny house was safely covered by the tarp.

Having grown up in Puerto Rico, this blue tarp reminded me of the tarp roofs that FEMA would install after a hurricane would peel the roofs off of houses.

Once the weather improves, we can continue working on the tiny house. Slowly but surely, we are installing the plywood roof panels onto the rafters.

Sheathing the Tiny House

The plywood sheathing that wraps the house serves many purposes. It helps keep water out of the structure as construction progresses but it also provides stability to the tiny house. Plywood is composed of three sheets of wood oriented with different grain directions.

Some plies have vertical grain, others horizontal grain, and the rest have diagonal grain. This gives the plywood strength in all these different directions. A square of 2x4s can easily collapse, but when it is sheathed, it will hold its shape under incredible loads!

Sheathing the tiny house in plywood enables us to remove the wooden stays as stability is introduced tot he structure. 

My dad and I would position a sheet of plywood and tack in a few screws to hold it in place, then we would add a few more to keep it well attached to the house. Later, we would run around the house placing a screw every foot in each stud of the frame. This ties the house together with such great strength that we felt confident enough to stand on the tops of the walls while working on the roof.

The problem is, there are lots of studs and tons of screws to drive in! I highly recommend using a drill with a driver on it, as it makes the process proceed incredibly quickly. Light weight is another wonderful feature, as the drill will begin to feel heavy and make stabilizing the unit hard as the work progresses.

Even with the ease of power tools, driving in each screw is very time consuming. Maddie spent an entire afternoon sheathing the "no door" side and front of the tiny house!

Lastly, cordless battery powered drivers are amazing! You never have to worry about the plug separating or the cord not reaching. Lastly, have fun while you do it because you are building your tiny house!

Installing the Rafters

The structure is now rather flimsy with all that weight aloft and hardly any support to it. The structure wracks in the wind since it lacks support from the roof.  The rafters will connect to the ridge beam and tie them to the wall frames. On a boat, these rafters are analogous to futtocks leading to the chine log.

The rafters are connected to the ridge beam with strong-ties and to the wall frames with hurricane anchors. The rafters are set 24" O.C. with exception to the butt block bolts. The rafters near the change in pitch of the roof are doubled to give each point more strength as the roofs change pitch.

The trusses sit a bit lower than the rest of the rafters to allow a sandwhich plank to be set between the truss and plywood roof to add the extension.

The tiny house is starting to take shape as it looks more and more like a house. Later on, boards that will be analogous to floors in a boat will be installed in the rafters below the ridge beam to tie them all together and make the structure even stronger!

Installing the Ridge Beam

The ridge beam is a massive piece of douglas fir weighing 130 pounds and measuring 18 feet long. I am not a home builder, so I designed this tiny house using boat building rules. If the house were flipped over, this beam would become the keel and it is sized accordingly. My rational is when heavy snow piles up on the roof, this ridge beam is going to have to bear the weight of it all and must be built to withstand the hypothetical task.

The ridge beam is going to rest in small metal channels that are set at the top of the trusses. These metal strong-ties will securely connect the end of the beam to the truss.

The only problem with our plan is we had to raise 130 pounds of 18 foot ridge beam 13 feet into the air. Rigging to the rescue!

The beam was carried into the tiny house via the back window on its side. It was fed into the house at an angle with the forward end passing over a temporary support to the frame walls. Additional 2x4s were placed across the frames to help support the beam. This gave us a very strong point to rest the beam on and if the beam fell, it would only go as far as the wood cross members.

Strong screws were used as blocks to guide a rope to make a pulley system. Two screws were set into the truss, one on each side of the peak, and a third screw was set on the underside of the ridge beam to keep the rope from slipping off.

A rope was securely tied to the trailer to provide an anchor point, over the truss, under the beam, back over the truss, and out to my mom who was manning the ropes. This assembly was tied on both ends so that as we (my dad and I) heaved the beam up, my mom could take out the slack in the line. This provided enough purchase for her to comfortably hold the beam in the air while we rested. We would heave up a few inches, then she would take up the slack, and we would rest; then repeat!

The screws and wood edges offered too much resistance to pull the assembly up by the pulley system, so it was relegated to holding the beam up and taking out the slack. We raised the single width section first and positioned it into the strong tie at the top of the truss and a lashing was tied to the beam to keep it attached to the truss while we focused on the other end of the beam.

The very heavy end (with the scarf joint and butt blocks) needed to be raised above the truss and lowered into the strong-tie channel to fully secure it. This came down to brute force as there was no nice way to rig a pulley system to hoist the beam into the place. I bit the bullet and lifted the very heavy beam high up and carefully into position. Then the ends were secured with screws to hold it in place!

Due to the extreme weight aloft, we had set up wooden stays inside the structure which were tied together and to the floor. We were very happy these were in place when that weight loaded the walls. If we were building on a level surface, they might not be needed. Being how we are building on a slight incline, the whole structure is leaning back. All of that weight up there would easily rip the trusses out and send the upper structure crashing down!

Now that the ridge beam is installed, it's time to start adding the rafters.