Book review: The Bio-Integrated Farm by Shawn Jadrnicek

A Revolutionary Permaculture-Based System Using Greenhouses, Ponds, Compost Piles, Aquaponics, Chickens, and More

In my experience farmers and gardeners aren't philosophers, they're doers. They want to know why ― but most importantly they want to know how.

In this quote, Shawn Jadrnicek summarizes what I like best about his book. When I first got into permaculture in the mid-2000s, most books were heavy on theory, but light on practice. Bill Mollison's epic Permaculture: a Designer's Manual has lots of great ideas and big claims. But good ideas on paper don't always end in good results in the real world, and details of implementation can make or break even the best ideas. For successful replication, a designer needs to know what worked and what didn't, under which circumstances. Which elements need to be included? What patterns matter?

Dave Jacke and Eric Toensmeier's Edible Forest Gardening provided the needed details, grounded in ecological science, for a field until then mostly dependent on anecdotes. Now Shawn Jadrnicek, with the help of his wife Stephanie, has applied similarly rigorous analysis to the subtitular greenhouses, ponds, compost piles, aquaponics, and chickens, all system elements popularly used by permaculture practitioners. There's plenty of information out there about how to build and manage each of these elements in isolation, and much of the permaculture literature offers good ideas for building functional relationships between them. But this book, based on experience with commercial- and home-scale areas, shares the knowledge and wisdom people need for successful integrations.

For example, Mollison and other permaculture authors suggest that chickens, greenhouses, and plants can coexist in a natural and easy combination. When temperatures get cold, chickens move into the greenhouse, adding heat when the plants need it, and improving plant growth by increasing CO₂ availability. Jardnicek opens the section "Connecting Chickens to the Greenhouse" by stating:

Before implementing this project, I'd read a lot about connecting chicken coops to greenhouses ― and in theory it works. But as with all theories, the application itself presented challenges. In a nut-shell, chicken coops connected to the greenhouse are both beneficial and problematic.

After experimentation in his South Carolina location, he discovered drawbacks to the theory: plants don't use the extra CO₂ at night, when the chickens spend most of their time in the greenhouse; failing to open the coop early each morning may cause heat stress to the chickens; high heat levels may dissuade the chickens from returning to the greenhouse to roost on summer nights; ammonia from poop can quickly build to levels harmful to plants; and chicken dust doesn't mix well with raw veggie crops. He concludes that northerly climates are better suited to the combination than areas with hot winter (and even hotter summer) days. In fact, in any locale, it may be better to situate a chicken coop next to the greenhouse and move filtered air, rather than try for full integration,

The book excels in its attention to detail for the many uses of water. Jardnicek addresses residential needs, crop irrigation, multi-purpose ponds, moving nutrients across the land, and even using water flushes to separate acorns from leaves, with formulas or at least approximations to guide design in each area. He thoroughly covers moving water into and out of tanks, ponds, basins, and fields, and integration with greenhouses, plant nurseries, fish, aquaculture, and chickens. One of my favorite ideas is a system of self-watering seed trays, floating in ponds on Styrofoam rafts weighted to submerge the bottoms of the trays. The detailed description gives me confidence that I could make it work for myself.

Two factors prevent me from raving about the book as I did for Edible Forest Gardens and Martin Crawford's Agroforestry News. The first needn't hold back most readers: my tropical location makes much of the discussion of heat trapping and storage irrelevant. The second is more universal to anyone concerned with sustainability or self-sufficiency. Jardnicek relies heavily on industrial products: chicken and fish feed; pond liners and covers; pipes, pumps, expansion tanks, and valves; tractors and trucks; shade cloth and greenhouse plastic.

As Lierre Keith puts it in The Vegetarian Myth, "The absolute bottom line is: what methods of food production build topsoil while using only ambient sun and rain? Because nothing else is sustainable".

To be fair, much of what Jardnicek describes is for commercial-scale operations where the goal is almost always "less harm" rather than sustainability, and of course each reader needs to decide for him- or herself how much to design for true sustainability. But I think most of the described systems have unwise and irresponsible levels of industrial dependency, and the ideas need to be read with caution.

That said, I do recommend the book. I'm glad I read it, glad I have it for ongoing reference, and will likely reread it when the time comes to design my own homestead. Many of the principles and concepts could be adapted for my tropical needs and non-industrial ethics. I'm already brainstorming about seed trays floating on bamboo mats, or maybe on pond weeds...

Self Sufficiency, Five Years In - audio slideshow

In spring 2011, I gave a presentation three times on the progress, successes, failures, and lessons from five years of working towards self sufficiency with my ex-partner at our house in Portland. I advertised the event with this blurb:

In March of 2006, Tulsi and Norris purchased a small house on a .2 acre lot, and used permaculture principles to design their food forest, sun garden, and house renovation. They aimed to create a low-maintenance, truly sustainable habitat for 2-4 people plus wildlife, providing from the property all necessary food, heating & cooking fuel, water, and waste treatment. Join us for a reality check on what's worked and what hasn't, what seems theoretically possible for the future, and what all this means to the oxymoronic goal of a sustainable city.

I've finally synced up an audio recording I made of my presentation with the slide images, to make a sort-of movie. You can view the Self Sufficiency, Five Years In slideshow online (may require reasonably fast internet connection) or download a 36MB zip file for offline viewing. (Extract to anywhere on your hard drive, then open the included index.html file in your web browser.)

I've also created a video, which requires more bandwidth: Self Sufficiency, Five Years In on YouTube. (You can download the 166MB WMV movie file or watch it below)

Or you can download a 6 MB PDF of the slideshow without audio.

House heat update & unintended consequences

Fuel Used To Date

With the whole house almost completely insulated, we've burned about 38 cubic feet of firewood this winter, a bit less than 1/3 cord.  (One cord of wood is a pile 4' x 8' x 8', or 128 cubic feet.)  We've been keeping the sunspace between about 50-62F, with the north part of the house generally a few degrees cooler during the day, but dropping to the same temps overnight.  We've made a fire every 2 or 3 days on average.  We made at least 1/3 of those fires for guests or for house showings, not because we needed the heat for ourselves.  We're probably on track to use a total of 4/10 a cord of wood.  We scavenge all our wood for free, but market rate is around $150/cord, so we'll use about $60 worth of wood for heating.

We still have extra heat input from showers (about 3 per week) and from cooking on our gas stove (8 therms=800,000 btus since Oct. 18, or the equivalent of 1/25 cord of wood.) This winter has seemed unusually sunny, so our passive solar heat gain has been higher than in a normal winter.

Future Steps

I'm fairly pleased with our relatively low energy consumption this winter, but we're still far short of our original goal of heating the house entirely from on-site resources.  Some pieces we're still missing:

• Insulation for all house windows, especially sunspace windows, for better overnight heat retention
• Finish insulating attic
• Rocket stove instead of normal wood stove, for much greater efficiency in cooking and heating
• Install our 5 solar hot water panels and run the hot water through the radiant floor tubing
• Full growth of trees and shrubs for fuel from pruning & coppicing

Unintended Consequences

In past years, we used our daily fires through the winter to cook our jerusalem artichokes (aka sunchokes), converting the inulin to digestible sugars after 6-8 hours of pressure cooking. That worked well when we made fires daily. Now, with fires only every 2nd or 3rd day, it takes almost a week to cook the 3 pounds of sunchokes which our pressure cooker can hold. Last winter I ate twice that much per week. We could partially solve this problem with an additional and/or larger pressure cooker.

Same problem with processing acorns using our preferred hot leaching method. However, since we don't rely on a pressure cooker, we can "scale up" by using multiple pots of large size to leach the acorns, rather than relying on daily fires.

Similarly, without frequent fires, we're having a much harder time drying nuts, herbs, processed acorn meal, seeds, laundry, wet winter clothes, etc. Now I wish we hadn't sold our solar dehydrator last fall; we could have used it on our sunny winter days when we weren't making fires. If we were staying here longer, we'd probably set up the front porch or carport for initial drying of clothes, moving them inside for final drying as needed. Better yet would be a space protected from rain but exposed to the sun, such as my recent idea of an enclosed greenhouse to the south of our sunspace.

House Layout, Features, & Future Projects

Design Goals

Before embarking on our house project, we designed the final layout of rooms with a few criteria in mind:

• Active living space at the south end of the house, to utilize the light & warmth from the sun.
  
• Heat the entire house via passive solar with back-up wood stove.
  
• Bedrooms at the north end of the house where the reduced light and cooler temperatures don't matter as much.
  
• Natural daylighting in all rooms.
  
• Add significant storage area for food, preferably unheated space (canned goods, fresh produce, roots, etc)
  
• Integrate airlocks/mudrooms to reduce heat loss in winter and heat gain in summer, as well as contain dirt & wet clothes.
  

Goal Implementation

We built the sunspace at the south end of the house as one large room, suitable for a wide variety of active living uses - living room, dining room, party room, play room, study/office, etc. We "planted" our bath tubs to the south of the sunspace for extra heat & light gain in the winter. We planted a black walnut to the SW of the house, and built a grape trellis south of the sunspace for seasonal shade.

We installed an EPA certified wood stove facing the kitchen for radiant heat gain and comfort from the cheery glow. It heats the sunspace quickly. The sunspace sits 2' below the rest of the house, creating a natural convective loop of heat rising from the sunspace into the rest of the house, for fairly rapid heat distribution.

We added east windows looking onto the ecoroofs, to allow morning light into the NE bedroom, the pantry, and the sunspace. We added a wavy glass privacy window between the bathroom and the sunspace, since the bathroom had no natural light. The sunspace allows a lot of light into the kitchen and the SW bedroom (which also has a west window.)

We created a pantry with a 2' path down the middle and shelves lining the walls for efficient storage of lots of goods.

We didn't build the airlocks, but we left room to add them if desired: one in the sunspace around the back door, and one on the current front porch, enclosing the upper portion of the deck.

Other Features

The front porch makes a wonderful hang-out area in the summer, opening to the front garden to the north. Walls block the sun to the east, west, and south, and the ecoroof limits heat gain from above.

We made it easy to add a third bedroom (or office space) by constructing a single partition wall to turn the northwest portion of the house into a large closed off room.

We installed a sliding glass door between the sunspace and the kitchen, and of course the southwest bedroom has a closing door, so it's easy to isolate the sunspace for cozy temperatures in the winter without needing to heat the entire house.

We built nice big stairs from the kitchen to the sunspace, very inviting for people to sit and gather on.

When we lifted the original house and put a perimeter foundation under it, we wound up with three holes in the foundation wall so the I-beams could lower the house onto the wall. We discovered that in the summer, opening those holes creates a natural air conditioner as cool air from the crawl space flows into the sunspace.

Future Projects

If we were staying in this house, we would:

Add insulating curtains to the sunspace window wall. (And figure out insulation for the other windows in the house.)

Replace the wood stove with a rocket stove, for dramatic efficiency improvements in heating and cooking.

Remove the natural gas forced air furnace and associated ductwork in the attic, since we never use it and it wastes a lot of space (usable room space in the southwest bedroom, and insulation space in the attic).

Install the five hot water solar panels we bought, using them to heat domestic water and to run the excess heat through the radiant tubing under the original house.

Build a greenhouse on the south side of the sunspace, enclosing the bath tubs with the grapes growing on top. Move the chickens to sleep in the greenhouse.

Plant more plants on the west wall or west side of the house to create more summer shade while utilizing that growing space (without interfering with its current use as hang-out party space.) Perhaps plant akebia or scarlet runner beans against the house, and/or trees further out trained to high-branching trunks for easy human passage underneath.

Build a cold cupboard to tap into the cool crawlspace air and pull it up through a small pantry area to keep perishable foods a little cooler in the summer.

Site Plan

Here's the house in relation to the property boundaries, showing setbacks for addition of an Accessory Dwelling Unit:

House insulation & initial results

As part of our house renovation over the last two and a half years, we've added huge amounts of insulation, getting the whole house to an average of about R-30. Here's a rundown of what we did.

Materials

• Fiberglass - about R-3.5 per inch. Not the highest R-value, and kind of nasty to work with, but cheap. We got lots for free from craigslist, and lots for nominal cost from the Rebuilding Center, a local salvage/resale place. We used this in spots where we had ample room to stuff insulation and thus could use this cheaper product.
  
• Loose-fill (cellulose and rock wool) - R3 to 3.5 per inch. Our attic had a thin (~2" on average) layer of cellulose, and we got a few more bags for free from craigslist.
  
• Polyisocyanurate rigid foam board - R6.5 per inch. Expensive (even used, at about $10-$15 for a 2" x 4'x8' sheet), but highest possible R-value per inch. We used this where existing framing limited our available space for insulation: original house walls and the floor joists. Most of this had reflective foil faces on both sides.
  
• XPS rigid foam board (pink and blue board) - R5 per inch. Somewhat pricey. We got some used, but bought most of it new. Resistant to water uptake, and with high compressive strength, so we used this under the concrete slab in the new sunspace. Also used it in some walls where we ran out of appropriately thick polyisocyanurate.
  
• Reflective "bubble wrap", similar to the commercial "Reflectix." Petsmart receives their tropical fish in 2' x3' double-layered "envelopes" of this stuff; Tulsey arranged for us to pick up big stacks every 2 or 3 weeks, saving them from the dump. We used these as air and vapor barriers, and the bubble wrap probably adds about R-1, and they may have significant value in reducing radiant heat loss. (The last claim is somewhat controversial.) We did have to buy the shiny tape to seal adjacent strips together.
  

Application

Walls

Approximate R-value: 20

In the original portion of the house, we gutted two bedrooms with no wall insulation and filled them with 3" of polyisocyanurate (or in a few places, 2" of polyiso and 1" of XPS just because we ran out of polyiso materials to get us to 3".) We had to cut the insulation to size, which was not difficult, but was somewhat tedious. Next we furred out the walls with some old lathe, to make the total cavity depth a full 4". We built the east and west sunspace walls to be 8" wide, with 2 rows of 2x4 studs with 1" offset between the rows with scraps of rigid board to reduce thermal bridging. The south wall mostly has windows, so we built it with 2x6 studs. We filled all the sunspace walls with fiberglass insulation.

With all the walls, once we had the insulation in place, we ran the bubble wrap insulation over the interior face of the studs, then into the wall cavity until it hit the fiberglass or rigid insulation, then along the face of that insulation until the next stud. The goal was to create a 3/4 to 1" air gap between the shiny bubble wrap and the sheetrock attached to the studs. This air gap is critical for the reflective nature of the bubble wrap to reduce radiant heat loss.

Ceiling

Approximate R-value: 40. The bubble wrap acts solely as an air & vapor barrier, not as a reflective barrier.

Original House

We redid the ceiling in about half of the original house, so in those rooms I attached a layer of bubble wrap under the ceiling joists (on the room side). In the rest of the areas I nestled the bubble wrap into the joist cavities from above (similar to the application to the walls), first removing the thin layer of existing loose-fill cellulose. I'm using our loose fill to fill the 2x4 joist cavities, then laying fiberglass bats perpindicular to the joists to a depth of 6-10". (I haven't finished all the attic insulation yet--I'm about halfway done.)

In the funny little pop-out of our NE bedroom, there was no way to access the attic space after sealing it up from below. So I stuffed pink XPS between the joists to create a supportive "platform" on top of which I could put fiberglass and loose fill before applying the usual bubble wrap to the bottoms of the joists.

Sunspace

We built the sunspace ceiling with 2x12 joists, in part to support the ecoroof load. We also built a 2x4 drop ceiling under that, so we were able to place about 13" total of fiberglass insulation. We finished with a layer of the bubble wrap insulation attached to the bottom of the drop ceiling joists before attaching the sheetrock.

Floor

Approximate R-value: 30.

Original house

Under the original house, we had no insulation to begin with. About 60% of this area had 2x6 joists, the rest 2x8. With the help of friends, I installed 3/4" PEX tubing under the living areas, which takes up about 1" and needs another 1" airgap between it and the reflective surface of the polyisocyanurate below. That left 3.5" and 5.5" available in the 2x6 and 2x6 joist cavities; I stuffed these with 4" and 6" of polyiso (with 1/2" hanging below the joist bottoms.) I finished off with bubble wrap stapled to the bottoms of the joists.

Sunspace

Going with the design of our passive solar consultants (Urban Sun), we used 2" of XPS (R-10 total) under the concrete slab, and against the interior face of the stem wall. The low R-value is a little deceptive, since it's OK to use the ground itself for some heat storage in the interior of the slab. Only the outside edges will lose much heat.

Crawlspace

I placed 2" of polyiso against the foundation wall butting into the sunspace, to reduce the heat loss from the sunspace into the crawlspace. Around the rest of the walls, we glued the bubble wrap for a little bit of R-value and hopefully some help from the radiant barrier.

Initial Results

Today marks the first time this year we've felt the need to make a fire to heat the house! We've definitely made it way later into the cold season than ever before. Some notes on our parameters:

• We've been comfortable with the house ranging from 55F as a worst-case overnight low up to 61 or 62 or sunny days, generally in the 57-59 range during the day. Yesterday we were stuck at 55 all day long, and overnight dropped to 51, so we finally broke down and made the fire today.
  
• We've been cooking and baking a fair amount on our gas stove, which adds a lot of heat to the house.
  
• We've been taking hot showers every 3 days or so, which adds a lot of heat to the house.
  
• Before today, we had made 6 fires, but hadn't really needed any of them for our own heating comfort. We primarily made them for open houses and house showings as we try to sell our house.