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Green Remodeling - Day Two

 Remodeling vs. New construction:
  • More complicated
  • More unknowns
  • Less flexibility / more constraints
  • Site is fixed
  • Unexpected / unintended consequences
  • Dealing with occupants – customer service
  • Jobsite safety / indoor air quality
  • Historic preservation
  • Environmental hazards
    • Lead
    • Asbestos
    • Radon
    • Arsenic
    • Mold / moisture
  • Outdated systems / materials
  • Existing load paths
  • Hidden problems / treasures
  • Range of projects
  • Sequence of projects
  • Client / building professional relationship

 Green remodeling:

  • More holistic systems thinking
  • More “expensive” / greater value
  • Different technologies
  • Compatibility
  • Getting on the same “green” page

Building Profile:

  • Importance of examining site – not just building – many water problems come from the site.
  • Neighboring sites
  • Plans – may not be the same as the building – renovation etc…
    • If no plans exist, do your own measurements
  • Test for capillary breaks – use a moisture meter on concrete, wood or drywall.
  • Tape down a sheet of plastic to slab or foundation for 48 hours, if moisture condenses there’s a capillary problem.
  • Carpenter ants burrow in wood, makes nests.
  • Keep cordwood out of house – brings in moisture and ants.
  • Do inspection during rainiest times to see worst-case scenario.
  • Washing machines usually have a constant water supply – install a single-throw shutoff to turn it off easily.

 Roof – hot or cold roof?

 Hot:

  • Don’t vent roof assembly
  • Cathedral ceiling
  • No air leakage

Cold:

  • Vented roof – dries out roof deck
  • Vent outside the insulation
  • Have insulation towards inside

 Teacher’s Brattleboro home remodel:

Original house:

  • Un-insulated masonry block downstairs
  • Wood frame upstairs
  • Slate roof

Water management:

  • Gambrel roof drains at 4 points
  • Placed pine bark mulch at valley landings to soak up water and prevent leakage into basement

Windows:

  • Installed low-e storm windows over originals

Attic:

  • Sealed and insulated to R-38 w/ cotton insulation

Basement:

  • Was damp – vapor coming through the concrete
  • Walls need to dry to both inside and out
  • Built non-structural interior walls out from the concrete
  • Filled walls with vapor permeable spray foam called “icynene”
  • After sealing the drafts the radon levels increased from 6 to 12
  • Put in exhaust fan running 24/7 to deal with radon

 Second story:

  • Wrapped with foam insulation
  • Ran wiring through narrow baseboard molding to avoid cutting into walls.

Field trip to Jordan’s remodel project: View Gallery

  • Renting a small addition to an 1856 house – used to be a wood shed.
  • Concrete slab w/ crawl space and framed floor
  • Smells of mildew – high moisture readings
  • Rotted wood around outside clapboard exterior
  • Historic preservation idea – “underground roof” – if there is no possibility for installing gutters to control water runoff – install a waterproof membrane under the house siding and into the ground, buried under the soil and angling down away from the house. This allows water to run away as is soaks into the ground.

Green Remodeling - Day One

Green Building definitions are varying:
  • EPA definition (summarized): “…designed to reduce direct and indirect environmental consequences with construction, occupancy, operation, maintenance, and decommissioning with cooperation of everyone involved in the design and building process...”

Measuring an environmental footprint:

  • Site – units per acre
  • Waste – lbs per sq. ft.
  • Energy – embodied energy & operational energy – BTU per degree-day per sq. ft.
  • Materials – embodied energy – lbs or board. ft.
  • Water – gallons per person per day

The relationship between how heat and water move around buildings:
Heat transfer is always a mix of the 3 following:

  • Radiation – instantaneous, constant, speed of light. Moves from high to low through empty spaces. Energy can be temperature transmitted, reflected or absorbed.
  • Conduction – direct transfer of kinetic (vibrational) energy, from high to low in solids.
  • Convection – transfer of thermal energy by a medium – fluids, air and water.

 Radiant floors

  • Large surface area, slow to heat up
  • Air heats up over surface through convection
  • Floor transfers heat to walls through radiation.

 Windows

  • Inside house is 60% convection, 40% radiation, outside window is 80% convection, 20% radiation.
  • Inside a double-paned window is conduction, if filled with a gas that doesn’t transfer heat well there will be less convection.
  • Insulating shades can cause more heat loss if there are any gaps around edges – convection is encouraged.
  • Window spacers made of metal conduct heat if they aren’t insulated.
  • Low-e coating allows light while reflecting heat inside. The coating reflects radiant energy.
  • Low-e can coat inside of window for cold climate, or outside of window in hot climate to reflect and keep heat outside.
  • Coating effects light transfer and reflects color differently – avoid using on the south side for passive solar building.
Moisture flows in 4 ways:
  • Gravity – bulk liquid form
    • Lateral cohesive movement
    • Wind-driven rain
  • Capillarity – liquid form
    • The smaller the tube the further water can be drawn up
    • Air spaces create a capillary break
    • Place capillary breaks between foundation and wooden sill plate to prevent water from coming through the concrete.
  • Water Vapor
    • Air leakage – moisture flow
  • Diffusion
    • Migration of moisture by means of vapor pressure differential
    • Occurs in either direction between interior and exterior based on climate ad humidity.

 How moisture affects and moves through common building materials:

  • Vapor permeability – 1 “perm” = 1 grain of water moving through 1 sq. ft. in 1 hour
  • Some materials’ vapor permeability changes depending on how wet it is.
  • Plywood – the more wet, the more permeable – allows the material to dry
  • OSB – no increased permeability – glues prevent vapor dry out, retains moisture

How air gets around buildings:

  • Air in = air out
  • Wind effect
  • Stack effect
  • Combustion and ventilation

Heat and moisture move from high to low and warm to cold.

Damage functions:

  • Water barrier
    • Drainage plane
      • Exterior claddings
      • Concealed weather-resistive barrier
      • Flashings
    • Capillary breaks 
  • Air Barrier
    • Tyvek
    • Drywall
  • Thermal Barrier
    • Insulation
    • R-value – resistance to heat conduction

Vapor profile:

  • Latex paint – 17 perms
  • Wall board – 40
  • Cellulose – 75
  • XPS rigid foam – 1
  • Air space – 300
  • Wood siding – 35

Rules of thumb:

  • Keep outside of wall 5 times as permeable as inside to allow for drying toward the outside.
  • Roof – 10 times less permeable membrane than the roof assembly vapor barrier.

Solar Design - Day Two

Passive Solar architecture design ideas:

We already live in a solar economy – everything is dependant upon the sun – food, water, clothing, wood, etc…

Historical examples of passive solar design:
  • Old mill buildings, built before electricity have many windows for daylighting
  • Cupolas in barns provide light and convective drafts
Anti-solar buildings:
  • Frank Gehry’s Los Angeles opera house – the reflective quality of the titanium siding creates temperatures hot enough to roast a hot dog (our instructor shows us a photo of him doing so in front of this building).
Importance of materiality:
  • Lightness, color, glossiness, mass
  • Mass: stone, brick, adobe, concrete, water (enclosed in container, such as aquarium)
  • Balancing mass with glass to control temperature
  • Combining mass with insulation to contain heat
  • Lack of mass can cause things to heat up too fast with no mass to absorb the heat
  • Lack of insulation can cause heat loss
  • Dark colors will absorb heat
  • Light colors will reflect light
Begin with conservation:
  • Insulation
  • Durable, long-lasting materials
  • R-value = resistance to heat flow
  • U-value = conductivity of heat
Attached greenhouse
  • Roof glass or high vertical windows
  • Cover roof glass w/ canvas in summer
  • Vents from top of greenhouse into second floor of house will bring in heat
Trombe wall:
  • A wall with thermal mass (usually a dark color) is placed directly behind windows – light from windows heats up the mass, and vents bring hot air into house.
Creative lighting:
  • Place glass blocks in a ceiling to bring light down from above.
  • Glass skylight spine with rotating shutter – the shutter covers the north side in winter to prevent heat loss, the south side in summer to prevent overheating, and closes completely at night.
  • With thick walls, angle walls outward around windows to increase light flow around corners of the walls.
View Gallery of the class finding solar south and examples of photovoltaic systems.

Solar Design - Day One

  • Solar south – when the sun is halfway along its path through the sky each day.
  • Solar noon is not always the same as clock noon.
  • Time zones effect the difference between solar and clock noon
Warren, VT
  • Sunrise – 5:31 am
  • Sunset – 8:23 pm
  • Length of day – 14 hr, 51 min
  • Solar noon – 7 hr 25.5 min after sunrise
Photovoltaic
  • If one cell in a module is shaded – power from the whole module is lost, also affecting a series of connected modules.
Solar hot water collectors
  • If shaded, you only lose the percent of heat from the shaded area.

Sun hours
  • With panels at a 45º angle in winter, there’s an average of 2.9 sun hours a day
  • Average of 5.6 sun hours in July
  • Total average (in Burlington, VT) = 1,556 Total yearly sun hours
  • When under generating in winter and over generating in summer, sun hours can average out for a yearly total – useful for photovoltaic when grid-tied, and receiving payment for energy sent back to the grid.
  • If you are off the grid, this is not as beneficial – as you immediately need the energy you’ve produced.

Cost
  • It’s cheaper to invest in efficiency – buying a new, energy efficient fridge rather than buying solar panels to power the old one.
  • Off-grid – important to gather specific statistics on your electricity usage – appliance by appliance – to make sure you can produce enough.
Solar hot water
  • Flat plate collectors – 4x8’ – 32 sq. ft.
  • Recommended:
    • 20 sq. ft. -  per person
    • 40 sq. ft. - 2 people
    • Family of 4 – 2 collectors
  • At 45º angle – 3x more BTU’s in the summer
  • Hot water is 100% covered June-August
  • 30% covered in winter – need backup (woodstove?)
BTU – amount of heat it takes to raise 1 lb of water 1º in temperature.
  • Burning down one match is approximately 1 BTU

Passive lighting
  • 1 window = 2,000 watts of light
  • In some cases, a light bulb is more efficient than the potential heat loss in winter  and overheating in summer that comes with too many windows.
  • Skylights are a bad idea because they are angled toward the sun in summer, for potential overheating.
  • Design overhangs for south-facing windows
  • Avoid east-west facing windows – shade with landscaping and porches
Passive Solar Design

Site
  • Latitude / location / microclimates
  • Topography / elevation / wind / breezes
  • Water
  • Flora / fauna
Orientation
  • South
  • Sparingly glazed on east / west / north
  • Avoid roof glazing
  • Long-side facing solar-south
Landscaping
  • Deciduous / evergreen – when do they lose leaves?
  • Calculate future heights of trees
  • Evergreens shield house from winter breezes
  • Trim understory of trees near prevailing winds in summer – breeze will be cooled by the shade.
  • Avoid blacktops / driveways near south of house
  • Plant ivy arbors on east-west sides
Architecture
  • Daylighting – interior glazing – light, reflective wall color
  • Thermal layering – room placement
  • Locate heat-producing rooms, like the kitchen, on the north.
  • Mass absorbs heat – brick, stone
  • Sunspace – unheated, glazed – gain heat in day, closed at night
  • Attached greenhouse
  • Mudroom – airlock
  • Inside chimney
  • Shutters/shades on windows
R-value
  • Heat goes from hot spot to cold spots
  • Heat flows – radiation, conduction, convection
    • Conducts through solid materials – metal, masonry
    • Convection – drafts
    • Insulative – wood – non-conductive
    • Over-insulate slab and foundation because it’s hard to retrofit later
  • Glass
    • Low-e, double/triple pane
    • Avoid low-e / triple pane on south windows – hinders light transference
    • Insulate windows at night – shutters/shades

Redesigning Wastewater - Day Three

The final day was a project day for us to work on our own individual projects involving wastewater. The final projects were presented at the end of the day, and it was suggested that they include the following guidelines:
  • Goals
  • Constraints / opportunities
  • Users / uses
  • Supply – collection – treatment – reuse/dispersal
  • Flows – average and peak
  • Sources / characteristics / quantity
  • End use
  • Soil characteristics
  • Process flow diagram
  • Sizing / footprint
  • Power usage
My project: A composting toilet and greywater system for a future single-family house. Evan and I worked together because we’re designing for the same land.

Goals:
  • A wastewater system that accommodates a composting toilet and greywater system for a single-family home in Maine.
  • To transform waste into usable nutrients.
  • A low-energy, low-water use system autonomous and closed-loop.
Constraints:
  • Building code
  • Cost
Opportunities:
  • There’s already an existing septic tank
  • Maine code allows composting toilets
  • The land is well drained.
  • The ability to start from scratch.
Site Analysis:
  • 28 acres in rural Maine
  • 4-5 acre field – sandy, silty soil
The first thing we research is Maine codes and regulations – to see what is legal before we design it.

I found several options we could fall under – there is something called a “Primitive Disposal System” – which would allow a greywater system without a septic tank if no more than 25 gallons of greywater is produced a day (probably intended for rural summer cabins) – and if there is no water pump installed to pressurize water – only gravity feed from a tank holding no more than 1,000 gallons at a time. We were planning to have a gravity feed water tower any way.

There is also something called a “limited” system, which allows for 50 gallons of wastewater per fixture per day, with a maximum of 3 fixtures.

Any other sort of greywater system would require a septic tank to be in place – whether or not the greywater is actually sent to the tank. This is also not a problem, because luckily there is already a septic tank in place on the land. This is a big problem in many states for people who wish to design greywater systems, because the cost of putting in a septic tank when it won't even be used, can be a problem. We decide to go with this option, so that we are not limited by any regulations.

After researching in the book “Branched Drain Greywater Systems”, I came up with some calculations about the potential wastewater loads that a single-family house with efficient fixtures might produce:

Maximum wastewater - 4 people - gallons per week (gpw)
  • Shower – 364
  • Bathroom sink – 42
  • Kitchen sink – 168
  • Handwash – 14
  • Laundry – 90 (using a hand-operated washing machine that uses 15/gallons per 31 lb load.)
  • Total = 678 gpw
In a branched drain system, wastewater is sent through underground pipes that branch out in various directions, draining into buried “mulch basins”, that ideally end at a water-loving plant or tree whose roots will act to absorb and filter the water.

I read that you need about 1-2 sq. ft. of planted area for each gallon of water per week, therefore we would need around 700-1400 sq. ft. of planted area around the termination of the pipes.

Some water-loving, edible plants include:
  • Apricots
  • Peaches
  • Blackberries
  • Elderberries
  • Raspberries
  • Pecans
The square footage would include the canopy area of the tree, keeping in mind future growth – plum, peach, cherry and apricots might have around a 15 ft. diameter, with an average of 100 sq. ft per tree. The book conveniently has some statistics on square footage of tree canopies, and I figured out we’d need 7-14 trees/bushes for the greywater system. Because we’re planning to have an edible permaculture landscape anyway, this works out well, and is also convenient for keeping the trees irrigated.
 
These images show the greywater drain system (represented by the blue lines) with each one coming to an end at a planted tree or bush. This drawing isn't really to scale, and in reality, the drains should be kept fairly close to the house to prevent freezing.

 
The composting toilet system would be a 55-gallon barrel with an aerator, vent and urine diverter. The barrel would be interchanged as it fills up, and brought outside to an outbuilding to continue composting. The aerator keeps the waste stirred, and if it is mixed with sawdust, vented well, and has a tight-fitting lid, it shouldn’t smell. The waste wouldn’t have to be handled until it becomes compost – as it is simply replaced with a new barrel for the bathroom, while the old one sits. After it has fully composted and reached the temperature level for killing pathogens, it could be used to fertilize fruit trees.

The urine diverter would divert the urine to a collector, where it would sit until needed for use as a fertilizer.




A sources / flows diagram illustrating the path of the water. The blue lines represent cold water, orange - hot water, and grey - wastewater.

Redesigning Wastewater - Day Two

Design Process
  • Goals?
    • Water scarcity
    • Natural hydrology
    • Nutrient recovery – nitrogen/phosphates
    • Eutrophication – nutrient imbalance
    • Simplicity – ease of maintenance
    • Combined sewer overflows
    • Zero discharge
  • Site analysis
  • Constraints/opportunities
  • Characteristics
  • Users/uses
  • Design
  • Construction
  • Startup/operation
  • Preventative maintenance/corrective maintenance
3-5% of world’s natural gas is turned into nitrogen fertilizer.
Phosphate is strip-mined, a depleting resource. When used as a fertilizer, phosphates are concentrated in vegetables and consumed by humans. It can be recovered from human waste, but is difficult when waste is mixed with water.

Designs should include:
  • Conceptual
  • Schematic
  • Lifecycle cost/analysis
  • Basic flows and sizing
  • Process calculations
  • Engineering plans and specs
  • Operation and maintenance
Current Issues
  • Increasing wastewater demand
  • Aging infrastructure
  • Sewer overflows – 1/8” of rain in Pittsburgh causes an overflow
  • Poor maintenance and operation
  • Imposing nutrient limits
  • Unwillingness to pay maintenance costs
Emerging Issues
  • Water scarcity – not just in arid places
  • Nutrient scarcity – phosphorus for agricultural fertilizers
  • Electricity cost and availability –12% of US electricity goes to wastewater treatment, powering pumps.
  • Greenhouse gas emissions – Co2, methane
  • PCP’s and pollutants – pharmaceuticals
  • Increased demand for onsite decentralized systems
  • Co2 emissions from waste is part of neutral carbon cycle
    • Methane accelerates process – 20% more potent
    • Nitrous oxide is 160 times more potent
  • Pharmaceuticals that don’t get metabolized end up in waste, as well as caffeine and preservatives.
  • Hormones in waste are diluted so much that they won’t affect people, but do disrupt aquatic systems – can cause sex-reversal to female fish and amphibians.
  • PCP’s and dioxins bioaccumulate
Direct operational electricity usage:
  • Activated sludge and oxidation ditches – more electricity
  • Treatment wetlands and composting toilets – less electricity
Philosophical questions – value of water
  • Should wastewater become drinking water?
  • Should water be used to transport waste? Flush toilets w/ greywater or no water?
  • Life-cycle – energy inputs
  • How much can we rely on the environment to cleanse water before it’s pure?
Traditional systems
  • Septic tanks must often be 100ft from well
  • Concrete box in the ground
  • Wastewater comes in one end
  • Heavy solids sink to bottom – sludge
  • Grease floats to top – scum
  • Fermentation of sludge creates air bubbles/gases, carrying particulates up to scum layer
  • Clear zone – water/effluent going into drain field
  • Most tanks have 2-5 days of retention
Conventional leach field trench:
  • Trench backfilled w/ gravel – perforated pipe percolates water/effluent, filtered by soil ideally before it reaches groundwater.
Failure mechanisms – septic
  • Accumulation in pipe
  • Solids clogging soil pores
  • Biological growth clogs soil – biofilm grows w/ nutrients
  • Pre-treatment – wetlands control carbon
Strategies and Technologies
  • Conservation
    • Water
    • Energy
  • Source separation
    • Greywater/blackwater
    • Urine diversion
  • Reuse
    • Water
    • Waste
    • Nutrients
Components of wastewater by source:
  • Kitchen sink/dishwasher
    • Food residues, detergents, grit, oil, grease, cleaning products
  • Bathroom sink
    • Soaps, toothpaste, saliva, blood, mouth wash
  • Shower
    • Soaps, cleaning products, bodily fluids, hair
  • Laundry
    • Detergents, grit, soil, grease
  • Toilet
    • Feces, urine, paper products, cleaning products
Source separation:
  • Composting toilets
  • Urine diversion
  • Greywater
  • Blackwater
    • Solids must be filtered through septic tank (primary) before put through constructed wetlands as secondary treatment, and then disinfection before reuse.
  • Special waste streams
Greywater:
  • Water conservation / flow reduction – low flow
  • Treatment – then dispersal or reuse
  • Direct soil dispersal via infiltration chambers
  • Non-potable reuse after sand filters and disinfection
  • Sink water – pipes – screen – surge tank – pump – filter – subsurface drip irrigation
  • Sink water could also go to buried dispersal chambers covered with mulch.

Blackwater:
  • Water conservation / flow reduction
    • Microflush toilets / dry toilets
    • Waterless urinals
  • Passive blackwater treatment:
    • Clivus system, indoors, leaches liquids into wetland
    • Urine diversion:
  • Collection – urine capture
  • Treatment – ozonation, letting it sit 6 months – self-sterilizes
  • Reuse – direct fertilization w/ dilution
Design Scenarios
  • Conventional septic
  • Septic w/ treatment
  • Urine diversion w/ or w/o treatment
  • Composting toilets w/ greywater treatment
  • Grey/blackwater separation w/ reuse to toilets
Lifecycle energy for water
  • Extracting from source
  • Pumping to homes
  • 95% of energy is used to heat water
  • Wastewater pumps/treatment
Water Reuse
  • Non-potable
    • Indirect – groundwater – injection wells to replenish aquifers
    • Direct – irrigation, toilet flushing, showering, laundry
  • Direct-potable
    • Wastewater = drinking water
  • Indoor natural reuse systems
    • Greywater waters plants indoors/greenhouse
  • Commercial reuse for toilet flushing
    • Living machine – planted aerated basins
Evening Lectures

Compost (making safe, usable compost from human waste)
  • Pathogens are in waste/Greywater
  • Coliform can grow in plumbing system
  • Temperature of 150º sterilizes compost of bacteria
  • Different pathogens die at different rates/temperatures
  • Safety zone – 1 day at 122º F will kill all pathogens
  • Worms live the longest – hard to kill
Requirements for adequate compost:
  • Moisture content – 60%
  • Aerobic conditions
  • Carbon/nitrogen ratio – 25:1
  • Temperature reaches 122º-140º F
  • Biodegradable carbon source
Constructed Wetlands
  • SEEDS (teacher’s company) design precepts
    • Reuse material
    • Recycle water, energy and nutrients
    • Reduce lifecycle cost and impact
    • Use passive and renewable processes
    • Respect context
Example design project: “Forest Hostel” in GA
  • Problem: had a Greywater cesspool – drained into ground, saturating soils and rising to surface
  • Located in a forest wetland
  • Solution: built a constructed wetland to treat greywater
Design:
  • 2:1 – length/width size of wetland 7x14’
  • 1.5’ gravel depth, larger gravel around edges
  • 1 gallon water per sq/ft
  • Wetland is lined w/ high density polyethylene – lasts 50-60 yrs
  • Sand base under liner
  • Pea gravel on top for planting
  • Kitchen greywater needs a grease trap, under sink or in ground if bypassing septic tank.
  • Some edible wetland species:
    • Greens – arugula, cabbage, kale, lettuce
    • Herbs – mints, parsley, sorrel, basil
  • Oversize wetland for cold climates – design for worst case scenario
View Gallery - a tour of the septic system, and various alternative waste systems on the Yestermorrow campus.

Redesigning Wastewater - Day One - Evening

What is wastewater?
  • What you put in it
  • Second use
  • Pathogens – non potable
  • Organic material
  • Inorganic material
  • Nutrients
  • Energy
  • Pharmaceutical
  • Domestic
  • Agricultural
    • Pesticides/fertilizer
  • Commercial
  • Industrial
    • Toxins   
  • Blackwater – human waste
  • Greywater – sink, shower, laundry water
  • Yellow water – urine
Distribution of nutrients
  • 60-80% of nutrients in blackwater come from urine – can recover urine separately to use the nutrients.
  • Small % of greywater is black – food from kitchen sinks, waste from dirty clothes in laundry.
Waste treatment – centralized vs. decentralized
  • Centralized:
    • Vast network of collection pipes for central treatment
    • Efficient but energy intensive
    • Cities usually gravity feed the waste to low-lying areas, often rivers
    • Pipes are difficult to maintain
    • Sensitive to stormwater
  • Decentralized:
    • Dispersal or reuse
    • Single house w/ septic
    • Constructed wetland treatment for pumping water back into toilets
Types of decentralized systems:
  • Individual – onsite septic, settles and filters through ground
  • Cluster – connect systems into one, in small groups
  • Community – 100’s of homes brought to one point

Greenhouse Design/Build - Day Two

The second day of this weekend workshop, we went on tours of greenhouses. Most of them were commercial nursery greenhouses designed and built by one of our instructors - it wasn't very useful seeing several very similar greenhouses throughout the day, not to mention that they were all commercial scale - not what I'm interested in building. The only small scale greenhouse was our instructor's home greenhouse, attached to his house, which also wasn't being used for food production. It would have been helpful to have seen some greenhouses used on farms for this purpose.

View Gallery

Greenhouse Design/Build - Day One

Of the very short, limited lecture we had during this class, these are the notes I've managed to come up with:

We look at the “biodomes” in Cornwall, UK
  • Three different growing zones – rainforest, Mediterranean, agricultural
  • Water is collected in gutters on the domes and circulated into greenhouses
  • Steel hexagonal structure covered in membrane “pillows” made of thermoplastic “ETFE”
Design Criteria – what do you want out of a greenhouse?
  • Grow tropical plants?
  • Jump-start crops?
  • Extend growing season?
  • Multi-use attached space?
  • Winter livestock?
Energies
  • “Effective temperature” – combines effects of air movement, temperature, and humidity
  • Human comfort zone – 69º - 75º
  • Salad crops – 75º
  • 60º in winter – ok for fruit, tomatoes
  • 105º - cooking temp
  • 95º - max temp in greenhouse (GH)
  • 75º - perfect temp for photosynthesis
  • 55º - average winter temp in GH
  • 35º - minimum temp in GH
  • 15º - lowest temp for winter salad crops
  • GH temp usually 7º-15º warmer inside than out at night
  • Using cold frames inside a GH will raise temperatures/insulate more
  • Diffuse light for greens – too much light will cause them to grow too fast
  • Full sun needed for fruiting plants
    • “Daylight” – diffused natural light
    • “Sunlight” – direct sunlight, brighter
  • Direct south orientation is not too important with a freestanding greenhouse w/ glass on all sides.
Thermal Mass
  • Glass on south side
  • Mass, vent, insulation and water proofing on the north side
  • North wall stone masonry 6” thick is ideal
  • Mass floor – several feet of crushed stone creates thermal mass and drainage – water settles into gravel and radiates warmth back at night.
Insulation/materials
  • Two layers of glazing material creates a space for insulation
  • Two layers of polyfilm, inflated with a fan, filled with soap bubbles using bubble generators creates an R-30 insulation value.
  • A polyfilm interior with a corrugated plastic or fiberglass exterior holds up longer.
  • Other materials:
    • Polycarbonate
    • Aero gel
    • Translucent concrete
    • “Smart warp” – photovoltaics
    • Double or triple paned glass – should be tempered
Attached greenhouses
  • Need fans and side vents to control humidity
  • Must have tempered glass overhead
  • Double pane glass should be sealed, will fog between panes if seal is broken
Snow loads
  • Shovel sides of GH to prevent build-ups and cave-ins.

After the very short information section, we venture outside to build a gothic, arch-framed greenhouse.
View Gallery - of the frame building.
Unfortunately, I don't think I got much of a grasp on the material - most of the information was about new, high-tech materials for greenhouse siding, and some information about temperature, but no basic info on design. We weren't even shown a design for the greenhouse we were about to be building. What we did manage to build was just a frame - it could have been a frame for anything, and because we never got to siding and installation, I don't think I learned much at all about how to build a greenhouse.

Community Design - Final Projects - Part 2


The plan for the Artisan Village. I wanted to create a townhouse type village with courtyards creating community gathering space, workspace and garden space. I decided to separate the live/work studios, the apartments, and the commercial stores into three buildings. The plan shows that the apartments and studios are south-facing C-shaped buildings, attempting to cup the sun as it travels through the sky, while also creating some interesting shapes rather than two straight rows of buildings.

The commercial building has its storefronts facing west, not ideal for passive solar, but is the least important building to be passive solar because it will not be lived in. West also faces the road, where visitors/customers will have direct access without disrupting residents, and I wanted to enclose the courtyard in the center. There is a small parking lot in front of the commercial building for customers, and a lot off to the side for apartment residents.

 
The studios are actually two separate buildings with a narrow, trellis-covered alley between the two buildings, ideal for direct access when walking to or from the school zone. The buildings are laid out to have art studios downstairs (such as woodworking, ceramics, metalsmithing, etc…) and apartments upstairs. The studios would either be rented by the artists living upstairs, or possibly owned and used by Yestermorrow for classes, while residents of the village would have universal access as part of their rental fees. The buildings have an entrance at each knuckle, with a wedge-shaped hallway with stairs, mailboxes, etc, and a covered work area in the courtyard to the south.

The apartments are all one attached building consisting of 1 and 2 bedroom apartments, with community garden space in the private, south-facing courtyard.


The commercial building splays out in an arcing shape, wedged in to fit between the other two buildings, with more storefront space on the curving west side than on the straight east side. A covered patio creates outdoor café space and shades the stores from western sun. A clerestory spanning the spine of the building will light the stores from above – this is much like the clerestory on the existing school building, which works very well despite the fact that the building faces mostly east-west.


A cross-section of the village looking east.
The studio apartment buildings are taller and larger in general to accommodate for the high ceilings in the studio workspaces. They are located to the north of the apartments to prevent any shading from the sun. Both buildings are a saltbox timber frame design, allowing for more window space on the south sides of the buildings, with dormer windows on the north sides for space and ambient lighting.


I drew in some sun angles during the peak of the summer and winter months, to demonstrate how winter sun will penetrate the windows, while summer sun will be shaded out, and also to consider how large an area would be shaded in the courtyards between the buildings, to allow for sunny gardening space. The buildings would be built using natural building techniques, with thatch roofs and wood-heat.

 

   

Some freehand sketches of the village from different angles.