Working on home construction in a Wisconsin winter can be a cold situation! That’s why I was eager to get my Tiny House insulated to trap in the heat and keep out the chill.
Since warm air rises, most heat loss occurs through the ceiling of buildings. That’s where we decided to start insulating for maximum impact!
One thing I’ve learned about construction is that it’s never simple. “Insulating the ceiling” was actually about a 12-step process. Here’s a rundown of how it all came together.
First, we installed foam strips in the centers of all the rafter pockets. These strips will give support to plastic ventilation channels that will be installed before the insulation. The strips were cut from 3/4″ rigid foam sheets and secured using nails with large green plastic washers.
There are holes drilled through the roof on each side of the ridge beam to allow for air flow and ventilation through the rafter pockets. The holes are covered by the metal roofing ridge cap which will prevent water from leaking in.
Next, Dad cut and we installed blocker boards between all the rafters on the bottom side. This limited the open area to a narrow rectangle about 1″ tall, rather than the gaping hole that was there before without these boards.
I used Great Stuff to seal the cracks around the edges of the blocker boards.
Then it was time to install the plastic ventilation channels. With these in place, the top 3/4″ of the rafter pockets (along the underside of the plywood ceiling) will stay open to allow air flow up and out of the house. Without these, the insulation would push all the way up to the ceiling and block the ventilation from air trying to travel upward.
I used more Great Stuff to fill in the gaps between the rafters, blocker boards and plastic ventilation channels at the bottom of each pocket. This will keep the air flow where I want it – on the top side of the ventilation channel where it belongs!
Finally it was time for the actual insulation! A lot of people use rigid foam boards to insulate their Tiny House ceilings because they offer more R-value, or insulating power, for the thickness. But those boards are also significantly more expensive than fiberglass roll-style insulation, which was more in my price range. I chose R-19 formaldehyde-free fiberglass insulation, the thickest stuff I could fit between my 2 x 6 rafters.
The fiberglass insulation was easy to work with and simple to cut and staple inside each rafter pocket.
It can be kind of nasty to work with though because it’s made up of fiberglass shards that can cut and irritate your skin. You also don’t want to breathe this stuff in. Protective gear recommended!
The loft ceiling is all insulated!
Finally, the ceiling was fully filled with fiberglass insulation! With each piece installed, the house felt noticeably warmer.
Next, Dad created some cardboard templates to cut rigid foam insulation triangles for the loft walls.
Mom taped up all the seams to button up the wall insulation and keep things extra cozy.
The next step was installing plastic over all the ceiling insulation as a vapor barrier.
Dad had a great idea to sneak in more insulation value for the ceiling by installing 3/4″ thick rigid foam panels on the outside of the plastic. We held these in place using nails with big plastic washers. The ceiling paneling would be installed directly over this foam.
With one more foam board, the loft ceiling insulation was fully and completely finished!
We filled the 2 x 4 wall pockets with R-13 fiberglass roll insulation.
Before covering the electrical box wall with plastic, we needed to ground the electrical circuits to the metal trailer. We ran grounding cable from the box through the wall pocket and connected it to a metal hurricane holddown which is fused to the trailer.
After a wild goose chase of trying to find the right hex nuts to fit on the trailer’s hurricane holddown rods (needed a hard-to-find size), Mom went around and installed them on all eight threaded rods. We found even that to be easier said than done, since some of the holddowns were in very tight areas and some of the rods were a bit rusty and stubborn after being exposed to the elements during the construction process.
Mom also tackled the important but tedious task of insulating around all 11 windows with bits of fiberglass.
At this point we were ready to install the plastic vapor barrier on the Great Room ceiling and all of the first floor walls.
Mom was the master of folding and taping down all the odd edges of the plastic. “It’s just like wrapping a present!” she claimed. 🙂
Soon all the plastic was in place!
We worked together to smooth down and staple the plastic.
…And finished the insulation by installing the rigid foam on the Great Room ceiling! The foam goes all the way to the peak of the roof, but this was the last photo I got of the insulation before we covered it up with ceiling paneling.
Whew! I’m so glad to report that after the whole involved process, the house is all insulated and warm as can be 🙂
Look out for my next post which will have some exciting photos of the gorgeous interior paneling that makes up my finished ceiling and walls!