Dedicated Air

Air to supply the woodstove comes in through this duct hood...

...then passes under the first floor and up to the woodstove...

...then into a little add-on air-supply box under the woostove where the stove draws it's air. Once combusted, the fumes travel up the stove pipe...

...into the insulated pipe in the second floor living space and up through the roof...

...and back out to the great outdoors, having never mixed with the interior air

A key element required of a super-tight super-insulated house is insuring a dedicated air supply to all combustion. Likewise all combustion needs to have a dedicated vent route, also isolated from the interior air.

Two examples of this principal are the propane boiler in the basement which has a short in-and-out combustion air supply and the woodstove on the first floor. The woodstove, unlike the boiler, is located in the middle of the house so there is a good measure of ducting running from the outside supply hood to the woodstove and then exhausting from the wood stove up the stovepipe to the insulated stovepipe and through the roof. I've been quite careful to make sure the whole run is tightly sealed so that the woodstove is only pulling air from outside and only venting to the outside. I don't want any leaks.

The not-really-resolved aspect of this equation is the propane-fueled gas stove-top range. The air supply is the ambient household air, and the venting, such as it is, will be a hood mounted over the stove top. This will all work okay, but it isn't ideal. If we run the hood, we'll need to open a window or door to allow air in so as not to create a negative air pressure in the house which could then result in a back draft in the woodstove. We have carbon monoxide detectors on both floors even though they are not required by code since there will be a small amount emitted by the stove.

Onwards...

We've been wrapping up some odds and ends as we pause for Thanksgiving.

I cut the rest of the star pattern in the porch roof, which we then covered with (painted) tar paper. The effect is definitely diminished, which I'm kinda bummed about, but I'm glad they are there nonetheless. I wish I could think of some way to have them shine without having a translucent roofing material. Any ideas?

We cut holes for three vent pipes that pass through the roof as well as the stovepipe for the wood stove. The stovepipe will stand higher then it is shown in the photo when we add another segment from below and push it up and out a few more feet. We also taped up a couple of leaks revealed by a recent rain and added some more ice and water shield in the roof valleys for a bit of added security against future leaks.

To my satisfaction we engaged in a bit of materials management. Back a couple of months ago I ordered the wrong kind of rigid insulation for the basement. Its been sitting down there waiting to be returned for a long time, so we finally hauled it all out and had the lumber yard take it back, along with various other materials that we don't need. We moved the remaining 6x6's that will be needed for retaining walls on either side of the basement hatchway to near where we'll need them. That has opened up some space around the house that starts to let us feel the building as an entity on its own.

Today I spent the whole day cleaning up, organizing lumber stacks, gathering tools, clearing clutter, stacking rocks, separating and storing burnable lumber, sweeping, etc.... It felt really good to take care of all this stuff. It puts a little order and polish to our hard work.

Nancy's parents are coming for a post-Thanksgiving visit and I'm excited to show them our work. Before they get here I want to cut out a hole to get to the second floor from inside. As it is now its a little high climbing from the outside. From the inside it'll be an easy climb.

The weather continues to be generous to us, for which I am grateful