Last night Holly and I created a form out of pink foam that goes around the dry stacked blocks which forms the base of the chimney, stove and the shelves in the bathroom which lead up to the marine aquarium. We used blocks, clamps, silicon adhesive and foam in place to seal it all together.
Under the wood stove will be storage space for firewood. Being close to the stove it will be warm which will dry the wood further making for better fires. Most of our wood will be stored elsewhere – there’s not room in a tiny cottage of 252 sq-ft for the cord or two of wood we’ll use a year.
Behind the woodstove is a pair of air ducts that go up the back of the chimney. These separate the warm heavy masonry chimney tiles from the aquarium. Earth air pipes will come up the mountain bringing fresh air into the house and then go up through the air ducts on the back of the chimney. This acts as an air pump with no moving parts by using the chimney effect of the long earth pipes and the warmth of the chimney. Where ever possible I prefer avoiding the use of mechanical and electrical devices as they are simply one more thing that requires maintenance.
The total air duct height is about 40′ which should be enough to get a serious draft going making the issue being one of slowing the air. To that end the air will be circulated through the house in a loop that goes from the top of the chimney across the ceiling both north & south and then down to the floors. Both up on the ceiling and down at floor level will be adjustable grates for controlling the air flow.
If air is coming into the house, air must go out of the house. Some will go up the cook stove chimney year round. Some, the coldest air, will go out the floor air drains we installed in the slab. During warmer weather some will go out the windows thus pushing a curtain of air out which will keep insects, especially no-see-ums, outdoors. There will also be a hood over the stove for venting burning bacon fumes, the bathroom vent and an adjustable vent at the peak of the barrel vault to release heat during the hottest days of summer. Under the PAHS theory one would send the hot waste air through the surrounding berm to warm the soil and I may do that. I will lay the chimney design with that in mind.
Behind the twin air ducts behind the chimney is the bathroom closet and then the shelving in the wall that separates the bathroom, on the left, from the bedroom on the right (east). When doing the slab pour for the bond beam we placed inserts of 3″ of pink foam in each of the air ducts and the closet space to preserve those holes. That can be seen about half way back in this photo. Closer to the camera is the 661010 Welded Wire Mesh (WWM) to strengthen the slab under the wood stove and bind everything together.
This morning Ben and I went up to the tiny cottage. He made up five buckets of high slump PVA fiber concrete which I poured down the cores of the walls and then he made some stiffer mix for the bond beam and slab shelf that will support the wood stove. This locks the whole thing together tightly giving us a solid base for building the future heavy masonry stove. The goal is a combination wood cook stove and something similar to the Russian fire place masonry heaters. With such a small cottage it will be important not to overheat the place. There are some aspects of the designs of masonry heaters I like but some that are unsafe and can be improved. More on that in the future.
Outdoors: 40°F/30°F 3″ Snow, Partially Sunny
Farm House: 66°F/49°F two longs
Tiny Cottage: 54°F/45°F