Our back yard is a very busy place. A small digger is moving backfill soil around according to the landscape plan. The sheet metal workers are working at their benches. The insulation team has arrived with 2 truckloads of materials. Ron and lead carpenter Dave are having a meeting.
Alpine Insulation has the contract to insulate the building.
We considered spray foam insulation which is considered the best. After Ron did all of the calculations he concluded we couldn’t justify the foam. Here on the island we have mild winters and the small savings in the heating bill would not pay for the extra cost of spray foam over the life of the building. The eight-inch thick walls and high-efficiency construction method have already made the building thermally more efficient than conventional buildings. The design of a high-performance building envelope does more than anything else, more than adding any ‘green bling’ items, to reduce construction and operating costs over the life of the building.
R28 fibreglass insulation batts are pushed into the spaces between the roof rafters.
Batts are pushed into the spaces between the framing. The experienced installers cut the batts to fill the spaces evenly while pushing the batts in only so far to leave an air space next to the wall. All ductwork is surrounded by batts.
The walls are sealed with a heavy gauge plastic, caulking and black sealer along all edges. This air barrier must be in contact with the insulation with no insulation exposed. Sealing prevents convection currents building up fanning heat away from where it is needed.
The plastic is also a vapour barrier to control or stop condensation. High humidity moves to areas of low humidity and cooler areas such as the outer wall. The batts and the rigid foam insulation board over the doorways and window openings slows down the warming of the walls and increases the total insulation value of the walls. Insulation also reduces thermal bridging across materials such as wood which is a good conductor of heat.
The crawlspace walls and ceiling are insulated with batts and sealed. The floor pad had rigid insulation foam sheets and a waterproof barrier in place before the concrete was poured. The crawlspace needs to be sealed and unventilated to stop the flow of moisture and air into the space and up into the studio space. Buildings in the north ‘dry’ out so the walls need to let water go out which means the vapour barrier needs to be on the inside of the wall assembly.
While all of this activity is going on outside I am sitting inside calming stitching. Well, trying to. I must admit I do get distracted when something new arrives on the site.