Sustainable Organic Farm

Design description

2009

Purpose

The Farm Buildings have been designed to accommodate a family and staff, as well as occasional guests. It has been designed to provide a working example of a high performance, low embodied energy building which could easily be replicated on a larger or smaller scale.

Design

Main House

Access to the houses is from the Northern corner of the land. A road lined with native new-plant woodland & fruit trees leads south from the bottom of Albert Street and then curves east, along the top most west/east ridge to a crossroads centered within a large residential garden & pond. An west/east foot path track provides access to the house buildings as well as the east plots.

The house has been designed on an east-west axis to maximize passive solar gain. The house is a timber-framed or recycled steel building with a sedum/ herb roof.

Barn

The Barn is located near the house on the top ridge, central to the land, and is constructed mainly of timber and strawbale infill.

Educational Learning Centre/Storage Garage

The Centre/Garage is located in the northwest quadrant and is constructed mainly of timber and hemp/strawbale infill.

Services

There are water, sewage & electrical services accessible at the entry to the site, at the bottom of Albert Street. These services will be utilized as needed on the site.

Electricity

Electricity will mainly be supplied to the buildings from onsite solar panels, wind turbines & possibly micro-hydro from the nearby Beaver River.

Residential town hydro access to the site may be initially utilized to supplement this supply as well as selling back power to the town through this source.

Materials

The structure is either a roundwood timber-frame or recycled steel structure using local timber from the Site and/or nearby properties. The external walls of the dwellings are hemp/strawbale on a stabilized earthbag stem wall or concrete mix foundation. The floor is of FSC wood or rammed earth that will provide a large thermal mass which will serve to regulate the internal temperature conditions. The loading on the roof will be carried by trussed rafters or recycled steel. The roof will be insulated using a combination of solid and loose hemp fibre or blown cellulose insulation.

Materials are dependant on approval by Ontario Building Code regulations.

Farm Buildings Construction

Design

The House has been designed using a modular scheme which allows for a high degree of flexibility in the design of the individual dome units whilst specifying a common approach to the construction. The intention is to create a design that can be replicated easily and that is simple to construct.

Element	Material	Reason	Role	Source
Foundations	Concrete (Mix with pumice, flyash, lime…..) Hempcrete EarthBag Recycled Masonry	Environment Environment Natural Recycled	Structural Structural Structural Structural	Local/Ontario Local/Ontario From site/local Recycled/Ontario
Floors	Compressed/Rammed Earth Wood Adobe Brick Concrete (Mix…hemp)	Natural Natural Natural	Finish Finish Finish Insulative	From site/local From site/local Local Local/Ontario
Walls	Timber, wood frame Recycled Steel Earth Bag Strawbale Plaster – Earth, lime Rammed Earth Earth bag Recycled Denim Hemp Sheep wool Cob Eco-drywall	Natural Natural Recycled Natural Natural Natural Natural Natural Recycled Natural Natural Natural	Structural Structural Structural Skin Skin Skin Skin Insulation Insulation Insulation Interior Eco-drywall	Local Recycled/Ontario From site/local Local Ontario From site/local From site/local USA UK Local From site/local USA
Windows Skylights	Double Glazing Solartube EFT	Recycled Manufactured Manufactured	Natural Lighting Natural Lighting Natural Lighting	Recycled/Ontario USA UK
Roof	Metal geodesic frame Trussed joists Plasterboard Vapour barrier Hemp Insulation Green plywood Wood boarding Butyl Membrane Soil [Green Roof] Sedum/ Herb [Plants]	Recycled Manufactured Natural Manufactured Natural Natural Recycled/Nat. Manufactured From Site From Seed	Structural Structural Skin Membrane Insulation Finish Structural Membrane Environmental Environmental	USA Ontario UK USA Recycled/Ontario Local Local
Element	Material	Reason	Role	Source
Mechanical	Composting Toilets Radiant Floor Heating Solar Hot water heating Wetland grey & blackwater waste management Rainwater collection Biomass heating stoves (per room) Masonry Fireplace
Electrical	Building Biology principles of installation Biogeometry EMF protection Low energy/high efficiency bulbs Candles
Alternative Energy Systems	Geothermal Solar Wind [Micro-hydro]

Construction

The foundations will be made from a concrete mix of possibly hemp/limecrete with high flyash and/or pumice stone as well as possibly using recycled masonry (subject to building regulations approval).

The main structure will either be recycled steel or timber posts which will sit on pad foundations. They will support recycled steel or timber beams which will in turn support the roof. The floor will be insulated with hempcrete and above that will either be rammed earth or FSC wood. The external walls will be straw bale with earth plaster on the inside and lime plaster on the outside. The internal walls & finishes will be earth plaster, cob, eco-drywall with recycled denim, hemp or sheeps wool.

The roof will be supported either with recycled steel or trussed joists. These may be lightweight timber I-section beams made from recycled woodchips or local lumber. A possibility is to construct them on site using local wood from on near the site. This may eliminate the need for a large section timber roof structure. The roof will be insulated with hemp fibre or blown cellulose insulation and boarded with local or FSC wood planks or lined with [plasterboard to provide a fire retardant layer]. An EPDM membrane will provide a waterproof layer for the 70mm deep sedum/ herb roof.

Glazing will be double or triple depending on aspect. Windows and doors will be

either of softwood (FSC), recyled or local hardwood depending on their aspect.

Reversibility

The building is reversible insofar as the site could be restored to its former condition

with relative ease. After dismantling the structure the small masonry elements could

be dug up and removed. The concrete slab would need breaking up and removing

from the site. There would need to be some minor earthworks to return the site to its

previous incline.

Passive Solar Design

The Farm Buildings have been designed to maximize passive solar gain. The southern glazing

will capture the sun’s heat and this will then be stored in the massive floor.

Active Solar Design

The roof of the buildings will also incorporate solar water panels. This will be used to heat water for domestic use during the summer. Solar Water heating is technologically simple and works excellently to heat water in the summer. Water Accumulators will store this solar heat. We plan to be able to harvest all of the building’s hot water needs from the sun for 6 months of the year from the sun.

Ventilation and Infiltration

The buildings will be designed to minimize infiltration. The main entrances will be designed as airlocks.

Ventilation is provided in all of the ‘living’ rooms. In most cases this will take the form of

openable windows and trickle ventilation.

Natural lighting

All of the rooms have been designed to be lit under ordinary daylight conditions. Solartube ceiling lights will be added to supplement lighting into the rear hill side of the rooms as needed. Geodesic skylights will also be utilized in various feature areas.

Space/ Water Heating

The buildings will be designed to be super-insulated and thus require minimum heating. Heating will be provided by means of under-floor, radiant heating. This will be sourced from a large super-insulated water tank.

Heating Fuel

Fuel for heating will be sourced from a variety of different methods. Biomass stoves will be located in rooms with highest uses. A large central masonry fireplace with a significant thermal mass container will be utilized for the main rooms.