Homestead · heat, air, light
Systems
The house heats, and every light switches, with the server off. The boilers keep their own safety controls and every room keeps a switch that works on its own; the server supervises and schedules, and is never the only way to do anything.
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One tank, every source, in the hub, a building of its own: boilers are noisy, and no propane ever enters the house. In lead order: the outdoor wood boiler, through its protection valve and a plate exchanger with glycol on the buried side; a propane modulating boiler below a lower setpoint; an electric element below a lower one still or on the solar array's surplus; and the greenhouse's daytime surplus, into its own warm store first and the tank's cool bottom only when hotter (energy).
Out of it: hot water first, to a small indirect tank in each building, each with a mixing valve; the floors on outdoor reset, the workshop's slab and, through the tunnel, the house's; the air handlers' water coils; and the greenhouse and hot tub on their own glycol loop. The masonry heater and the fireplace are the fire's own path, not on the tank.
Built in order: the hub first, whole; its lines to the workshop with the workshop; on through the tunnel with the house; a branch for each building after.
The first heat numbers
An estimate by conductance and air leakage from the drawings' sizes and the envelope's R-values, at a design temperature of −25 °F, the state dwelling code's figure for this county, and about 9,000 heating degree days a year. It is not a Manual J and it sizes nothing; it shows where the heat goes and roughly how much wood it takes.
| Building | Held at | Design load |
|---|---|---|
| The house, 5,600 sq ft above grade and the basement | 70 °F | ~73,000 Btu/h |
| The workshop, 60 × 48, doors sealed well | 55 °F at work | ~50,000 Btu/h |
| The greenhouse, night curtains drawn | 40 °F at night | ~57,000 Btu/h |
| The greenhouse, no curtains | 40 °F at night | ~89,000 Btu/h |
| A year | Million Btu |
|---|---|
| The house | ~141 |
| Hot water for six | ~13 |
| The workshop, 45 °F idle and 55 °F at work | ~74 |
| The greenhouse, less the sun's day gain (est. 40 %) | ~42 |
| The hot tub, covered (est.) | ~12 |
| Total | ~281 |
At a gasifier's ~75 % seasonal efficiency (estimated) that is about 16 of oak and maple; 19 of mixed hardwood; 25 of aspen and pine a year. The house is modest for its size because the envelope works; the air that leaks out of it is its largest loss.
Air and humidity
Every room sensed, every room ducted and zoned: a motorized damper on each room's supply and a radiant loop on each room's actuator, both run by that room's temperature and humidity sensor.
| Where | Serves | |
|---|---|---|
| Air handler 1 | the basement's mechanical room | the basement, the first floor, the wing and the lean-to, by floor registers from below |
| Air handler 2 | the warm attic over the main block | the second floor, by ceiling registers from above |
Each has a hot-water coil from the tank and a cold-climate heat pump coil for cooling and the shoulder seasons.
- Dry winters: a steam humidifier on each air handler, held under the ceiling a vapour-open wall can take at −20 °F. Foggers only where a room wants its own humidity: the root cellar and the greenhouse, never the house's air.
- Moist summers: the heat pumps and a whole-house ducted dehumidifier, with the floors' heat locked out; the cellar and the tunnel on a dehumidifier of their own, because a cool cellar is never ventilated with July air.
- Always: an energy-recovery ventilator for fresh air, bath fans on humidity switches, a ducted kitchen hood with make-up air. In fan-only mode the return near the masonry heater carries its stored warmth through the first floor.
- The green frame dries in the house. Cut and raised green, the frame gives up roughly 15–17 tons of water over its first few heating seasons (an estimate from green and oven-dry densities); the dehumidifiers and the ventilator carry it out, and the plaster and floors wait for the first heating season.
- Alarms stay separate: smoke and carbon-monoxide alarms are listed, hardwired and interconnected as code requires, and depend on nothing else.
Light
- Incandescent where people live, by the legal routes left since the 45 lm/W rule ended the sale of general-service incandescent lamps in 2023: multi-lamp fixtures of 25 W lamps (under 310 lumens a lamp is not a general-service lamp), 100 W G40 globes, and plug-in table and floor lamps on switched receptacles.
- LEDs where nobody lives: the basement, the mechanical and server rooms, closets, the pantry and laundry, the porches, the garage and workshop, and outdoors. That carries the dwelling code's rule that half the lamps in permanent fixtures be high-efficacy (SPS 322.49).
- Flame: kerosene mantle lamps, portable, for evenings and for when the power is out, filled at a lamp shelf in the mudroom by daylight. Not piped gas mantles: the code bans unvented heaters of any fuel and asks every heat-producing appliance to be listed (SPS 323.04). Every flame is counted in the humidity control.
Control
- A server room in the basement, 8½ × 10 ft beside the mechanical room: the network, the home-automation server, the lighting panels, every sensor's home run, and a UPS fed from the hub's battery.
- A keypad or switch at every room's door that works on its own: the panels map it to that room's lights even with the server down. The server adds scenes, schedules and the whole-house "all off".
- What the server does: reads every room, runs the dampers, humidifiers, dehumidifiers and boosters within their limits, logs everything and shows it on a page. It watches the boilers and the tank, and never overrides their own controls.
The wall and the roof
The frame stands in the room; everything else wraps around it outside, and dries outward. Lime plaster on wood lath between the posts, then a variable vapour membrane taped at every lap: tight in winter, open in summer, so the wall dries both ways.
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About 10 in outside the posts: a service cavity, 2x6 studs with sheep's wool between (R-21), 2 in of wood-fibre board (about R-7), a weather barrier that passes vapour, a screened rainscreen gap and lap siding. About R-28 against the code's R-21, and no foam: the wall has to breathe.
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A warm roof over exposed rafters: tongue-and-groove boards as the ceiling, the membrane, 11¼ in of insulation between sleepers, a 2-in board, a vented gap under the deck and black standing-seam steel (the roofs). About R-49 and 18¼ in above the rafters; the overhangs are framed thin, so the edge reads about 11 in.
At the masonry
The masonry heater is built to the IRC's 4-in exception, with solid masonry walls, and the frame keeps 4 in from it on every side. Every flue keeps 2 in of airspace from any framing, fireblocked at each floor with galvanized steel as Wisconsin's code asks (SPS 321.30(9)), and the fireplace's back face keeps 4 in (IRC R1001.11), the stricter of the two. Both stacks stand on their own footings.