This Deep Winter Greenhouse in Ohio was selected by Midwest Home as the 1st place winner in their Biophilic Design category. We are excited to share some details and images of this build.
Featured Project: A Deep Winter Greenhouse in Ohio
Designer: Conservatory Craftsmen
Architect: Craft Design Build
Details: Thermally Broken Aluminum married with traditional architecture, Three inter-connected spaces totaling 800sq ft, Many technologies including a GHANT system
What is a Deep Winter Greenhouse?
We all know the challenges of growing our choice of plants in a greenhouse: difficult to heat in the winter, challenging to cool in the summer. The goal of the deep winter greenhouse design is to remediate these problems in an environmentally sound method.
We know the earth has a constant temperature plus or minus 45°. Using that temperature as a constant, and utilizing the warming benefits of the sun, we have designed this conservatory/greenhouse to be ‘eco friendly’, use little or no fossil fuel to heat or cool, and enjoy a comfortable environment for plants and humans all year around. The purpose for the ‘3 pod’ design was to orientate the room to a south exposure given the limitations of the property line. We knew that the north side needed to have sufficient earth-sheltering benefits and the south exposure required maximum solar exposure.
Initial excavation of the site to 60 inches below grade was the first step. SIP panels were installed over the footings for maximum insulation benefits. Geofabrics were installed over the earth and backfilled with coarse gravel, once ventilation tubes were installed for constant airflow into and out of the earth. Using the earth’s heating and cooling benefits in this manner is referred to as an ‘earth battery’. We are storing and using energy in the earth to use for climate control.
The floor was permeable pavers set over tamped gravel and sand. There were 16” diameter PVC tubes set into the earth battery on both sides of the room, in each ‘pod’. The tube set near the window was only 20” above grade, whereas the tube set near the wall 8′ up. Reversible circulation fans were set on top of each tube to either push hot air into the earth or to pull cool air our of the earth. This process reversed in the winter. Horizontal airflow (HAF) fans are set at the eaves to keep a constant motion of air in the room.
Windows operate automatically to balance air temperature in the space and blinds close automatically to shade against the hottest days of summer. The structure of this design requires a dependable automation design to be constantly aware of the changing behavior of the weather and climate change during a normal cycle of day and night. Our team designed and installed a very extensive system to constantly monitor the interior climate. Our weather station assists the automation in anticipating the needs of the system as it relates to the weather conditions of the day.
As an additional feature of environmental consciousness, all the rain and snow water from the building is collected in a cistern and reused in the greenhouse to water the plants.
The highly imaginative and creative interior design done by the homeowner has made this space multi-use as the beautiful design features have made this a great place to grow a tomato or host a party.