SBF# 15 Air sealing details

on the Pella windows I used Siga corvum 12/48 tape to connect the window frame to the foil face of the iso foam and Siga Rissan tape to the interior frame. Drywall gasket will be stapled to the tape and sealed to the drywall around the window. The Siga tapes are amazingly sticky. The Rissan tape is also stretchy to make good seals at the corners. It also has a mesh reinforcement.
This is the Siga 12/48 Corvum tape showing the 12mil section that is folded back to easily connect to the side of the window frame. The 48mil section is peeled and stuck to what ever surface you have next to the window frame. In this case the iso foam.






Here is an air barrier carried over the top plate of an interior bearing wall with gasketing to seal the drywall to.

The drywall is gasketed at all edges. At the bottom plate, a gasket is sealed to 10 mil vaporblock, which is carried to the basement.


This detail seals the beam penetration to the frame and used the drywall gasket to seal the drywall around the beam.

More air seal details to come....

SBF# 14 Granite chimney

The chimney is complete with the granite facing from the barn foundation.
The slabs were cut in half at a local granite shop and mortared and tied to the chimney.

SBF # 13 Heating & Ventilation come together

I believe that everyone is on board for the basic heating and ventilation systems.

Their current plan is as follows:
Heat- Primary - Margin wood cook stove
Backup - Electric element powered hydronic radiators(size to be determined) that would pull from upper coil in a Wagner 105gal tank.

Hot water - Wood cook stove direct to tank/solar to bottom coil in tank
Backup - Electric element

Ventilation - 2 bathroom exhaust only fans(Whispergreen/Fantech) on Grasslin intermittent timer and a kitchen exhaust with 4 Aldes passive inlet vents and a dedicated stove supply.

We decided not to use the spot ERV's because they operated as "exhaust only" for most of the time when it is cold when they will primarily be used, so the extra cost doesn't seem worth it. This fan might work better in a more temperate climate. It was a tough decision to give up the efficiency of the whole house HRV for the simplicity and economy of the passive vents.

The AC part of HVAC will be passive, using shades and manual operation of windows. The earth coupled basement will also contribute to cooling.

Below is the schematic from Karl Rosengrant, who works with Greenworks Solar. Probably the most interesting part is the controller on the radiant heat dump loop that will supply heat to the bathrooms and kitchen to keep the plumbing warm when the wood stove is out. The controller is connected to the solar controller, which has a read on the temp in the tank. This allows the controller to turn on the heat dump based on both the temp in the bathrooms/kitchen or the temp of the water.

To my grandpa - 4 generations

I still remember first hearing about solar panels and radiant heat from my grandfather. He is the builder that my father and I came from, and now my son. And then there's my stepfather's early career as a carpenter.

I am always amazed at the skill and understanding that is developed over generations when it is passed on through families from birth. Although our family didn't have a family based business, I have spent months and years working beside my father, grandfather and stepfather. This is the foundation of my experience. My earliest memories are of watching them work, learning how to operate shop tools, hammer nails and cut wood. Growing up in my stepfather's shop, I became familiar with how to shape, join and bend wood to achieve whatever was needed.

My father joined the carpenters union in Cleveland, Ohio and then became a chair maker. He built his house based one of Frank Lloyd Wright's circular passive solar designs. I was honored by him with grandpa's plane you can see above and will one day pass it on to Pan, who already has an instinctual hold and position with all of my tools.

Thanks grandpa, and here's to you. Did you ever think your great-grandson would be workin' your plane.

SBF #12 Heating system

The Margin Flame View cookstove is on site. With a thermostatic damper on the combustion air supply, that will be ducted in thru 3" pipe to the dedicated air intake port.
Small fans will be located in wall ports to move the hot air from the east side of the house to the west. 2nd floor vents will let the hot air up to the 2nd floor.

This constitutes the primary heat supply.

We looked at a heat pump to be backup, but with a price of 10K for primary capacity, it did not fit the budget. The basic idea here is to spend more on insulation and less on heating.

The owner decided he wanted a backup that would keep the house from freezing and protect from any damage. He figures the house will be maintained by a friend even if they are gone and to be able to drain all systems if there is a prolonged absence.
Looking at the heating system again, it made more sense to think about how we could take advantage of the heat dump for the hot water system and combine that with a backup for both hot water and heating. So I began to look into radiators that could bring extra heat from the hot water system and be supplied by an electric boiler if needed.
This preserves one of the primary goals of limiting any possible fossil fuel use, to the grid connection.

One draft heat loss analysis gave me a loss of 15,653 Btus/hr and then you might add 20% to account for coldest situation. The goal is to use less than 1 chord of wood for the heating season.

This can only be verified after a season of use. Stay tuned.

With heat loss we also have heat gain from windows/people/equipment as well as thermal storage capacity. I do not have numbers on this currently and the woodstove is probably oversized, but serves mutliple functions well. Having all the numbers would help more precisely size the heating system. As the owners were set on the wood cookstove, it was just a matter of the amount of wood to be used.
A more appropriately sized heater would have cost less.

By the way we removed a Peerless oil furnace, two 275gal oil tanks, a parlour wood stove and a bathroom electric heater.

SBF #11 - Ventilation/AQ

This post is likely to be controversial.
Against the recommendation of Andy Shapiro, who likes whole house ventilation. We will probably install 2 Panasonic FV-04VE1 Spot ERV's with low(66% @ 30 CFM ) efficiency and with max. 40 cfm each.

From panasonic:
WhisperComfort may also be suitable to meet whole house ventilations requirements under ASHRAE 62.2.

The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) set a standard for whole house ventilation, requiring that continuous mechanical ventilation be 7.5 CFM per bedroom (master bedroom x 2) plus 1 CFM per 100 square feet, with sone level not to exceed 1.0

Sunnybrook Farm: 2 beds + 1600 sq feet =38.5 cfm

We also are knocked out of Energy Star rating because we will not have kitchen exhaust(because there will be an electric stove, maybe with recirc. filter) and the ventilation is not above 50cfm. Again, the Panasonics are rated at 40cfm.

Reasoning-
1. The owner doesn't like the idea of installing all the ductwork for whole house system. He would prefer to open a window.
2. The house is small enough to get decent exchange with the two spot ERV's in the bathrooms.
3. The cost installed will be less than half of a whole house system.

We will also be supplying the woodstove with dedicated air supply with a thermostatically controlled damper on the intake.

The root cellar will also have thermostatic controls for ventilation.

It will be interesting to see how the blower door test turns out. If we are below 1ACH50, I think it could be useful to monitor the AQ. Check back for results.

I believe this design is only possible with a house that uses non-toxic finishes and materials that utilizes a free water vapor (or breathing) wall design. This means no vapor block in the walls/cieling. The air barrier must therefore be of a material that can allow water vapor to pass through but virtually no air to pass. We will be using 5/8" sheetrock. Clay and lime plasters also work and there are wood fiber boards that can do the same trick.

SBF#10 Windows are ordered

We decided on Serious fiberglass 725/525 series casement and awning windows with Pella wood clad "Natural Sun" windows on the south dining and den walls for the feel of wood.
Favored "H"(high solar gain) windows on the south/east and west and "L" to the north.

Specs:
Serious: double pane with heat mirror suspended film
Casement 7L : uframe-0.17 shgc-0.32 - North side
7H: uframe-0.19 shgc-0.56 - West/East side
Fixed 5H: uframe-0.18 shgc-0.57 - South side
Casement 5H: uframe-.22 shgc-0.57 - South side

Pella: double pane
fixed: uframe-0.30 shgc-0.56 "Natural sun" glass - south
casement: uframe-0.32 shgc-0.48 "Natural sun" glass - south
awning: uframe-0.29 shgc-0.27 "Advanced Low e" glass - 1 north window

29 windows for under $20K, spent a little more than budgeted(OK 27% over)
But not bad considering quality

Other considerations:
Fibertec -2nd(almost went with them- longer lead time did it, I think)
Thermotec - 3rd(too expensive for budget)
Optiwin-Energate-Linwood and more.

Now the doors....................
Linwood from Maine gave a decent quote for insulated wood entry door with 1/2 glass, multipoint latch and double gasket seal.
Looking at another local millwork shop in Barre, Vermont.
Hope to decide this next week.