Greenhouse Insulation Choices Described InspectAPedia® -
Advice for insulating a greenhouse
Advice for night time insulation for greenhouses or solariums
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This article discusses insulation options for greenhouses and nighttime insulation options for solariums and cold or drafty windows. The table of insulation properties at page top and accompanying text are reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss. Readers should also see INSULATION R-Values & Properties for a more extensive table describing the properties of different insulating materials.
Readers should also see GREENHOUSE DESIGN for SOLAR HEATING. Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
The question-and-answer article about insulation options for greenhouses or solariums, quotes-from, updates, and comments an original article, (see links just above) from Solar Age Magazine and written by Steven Bliss.
Question about how to best insulate a greenhouse against night time heat losses:
We have a greenhouse with a 30- by 20-foot vertical south-facing wall and have searched in vain for a thermally efficient and aesthetically acceptable nighttime insulation.
Also, we plan to add a brick floor on top of our slab which is insulated only on the perimeter and always feels cold. Should we put an inch of blue styrofoam under the brick to isolate it completely from the slab? We have no significant overheating problem. - P.P.
Answer:
A number of options for nighttime insulation were described in "Warm Wraps for Cold Windows", Solar Age, 6/83. Slab floors, even if they are insulated, tend to be chilled by downdrafts from cold window surfaces. So you should look for a window insulation with good edge seals to reduce the cold air flow at night.
If you find that window insulation does not solve the cold floor problem, then adding insulation to the slab would be in order. Your approach should work well as long as the brick will provide adequate thermal storage for your design.
To increase the new floor thickness, and thus its thermal mass, you can set the brick on edge. Since you are setting the brick over compressible material, a flexible (mortarless) paving system would be easiest. In this type of system, the floor bricks are tightly packed to one another without wet mortar. A mix of sand and dry mortar may be swept between the joints and dampened for a more solid and less permeable floor.
You may set the bricks on the foam insulation or add a layer of plywood underlayment first. In either case, a double layer of 15# felt paper is recommended directly under the brick to cushion and protect the underlayment. Since heat loss is greatest from slab edges, you might want to thermally isolate the new floor from the foundation walls by adding a foam strip at the floor's edge. You can conceal the foam strip with a baseboard (sketch above-left).
Here we include solar energy, solar heating, solar hot water, and related building energy efficiency improvement articles reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss.
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Solar Age Magazine was the official publication of the American Solar Energy Society. The contemporary solar energy magazine associated with the Society is Solar Today. "Established in 1954, the nonprofit American Solar Energy Society (ASES) is the nation's leading association of solar professionals & advocates. Our mission is to inspire an era of energy innovation and speed the transition to a sustainable energy economy. We advance education, research and policy. Leading for more than 50 years.
ASES leads national efforts to increase the use of solar energy, energy efficiency and other sustainable technologies in the U.S. We publish the award-winning SOLAR TODAY magazine, organize and present the ASES National Solar Conference and lead the ASES National Solar Tour – the largest grassroots solar event in the world."
Steven Bliss served as editorial director and co-publisher of The Journal of Light Construction for 16 years and previously as building technology editor for Progressive Builder and Solar Age magazines. He worked in the building trades as a carpenter and design/build contractor for more than ten years and holds a masters degree from the Harvard Graduate School of Education.
Excerpts from his recent book, Best Practices Guide to Residential Construction, Wiley (November 18, 2005) ISBN-10: 0471648361, ISBN-13: 978-0471648369, appear throughout this website, with permission and courtesy of Wiley & Sons. Best Practices Guide is available from the publisher, J. Wiley & Sons, and also at Amazon.com.
Excerpts with updates and annotations expanding the original Best Practices Guide text can be found in the online review and book summary at BEST CONSTRUCTION PRACTICES GUIDE and also at DECK & PORCH CONSTRUCTION, at INDOOR AIR QUALITY IMPROVEMENT GUIDE, and in other articles found at InspectAPedia.com such as HOUSEWRAP AIR & VAPOR BARRIERS, SOUND CONTROL in BUILDINGS, and other topics.
Passive Solar Design Handbook Volume I, the Passive Solar Handbook Introduction to Passive Solar Concepts, in a version used by the U.S. Air Force - online version available at this link and from the USAF also at wbdg.org/ccb/AF/AFH/pshbk_v1.pdf
Passive Solar Design Handbook Volume II, the Passive Solar Handbook Comprehensive Planning Guide, in a version used by the U.S. Air Force - online version available at this link and from the USAF also at wbdg.org/ccb/AF/AFH/pshbk_v2.pdf [This is a large PDF file that can take a while to load]
Passive Solar Handbook Volume III, the Passive Solar Handbook Programming Guide, in a version used by the U.S. Air Force - online version available at this link and from the USAF also at wbdg.org/ccb/AF/AFH/pshbk_v3.pdf
"Passive Solar Home Design", U.S. Department of Energy, describes using a home's windows, walls, and floors to collect and store solar energy for winter heating and also rejecting solar heat in warm weather.
"Solar Water Heaters", U.S. Department of Energy article on solar domestic water heaters to generate domestic hot water in buildings, explains how solar water heaters work. Solar heat for swimming pools is also discussed.
"Heat-Transfer Fluids for Solar Water Heating Systems", U.S. DOE, describes the types of fluids selected to transfer heat between the solar collector and the hot water in storage tanks in a building. These include air, water, water with glycol antifreeze mixtures (needed when using solar hot water systems in freezing climates), hydrocarbon oils, and refrigerants or silicones for heat transfer.
"Solar Water Heating System Freeze Protection", U.S. DOE,using antifreeze mixture in solar water heaters (or other freeze-resistant heat transfer fluids), as well as piping to permit draining the solar collector and piping system.
"Solar Air Heating" U.S. DOE also referred to as "Ventilation Preheating" in which solar systems use air for absorbing and transferring solar energy or heat to a building
"Solar Liquid Heating" U.S. DOE, systems using liquid (typically water) in flat plate solar collectors to collect solar energy in the form of heat for transfer into a building for space heating or hot water heating. The term "solar liquid" is used for accuracy, rather than "solar water" because the water may contain an antifreeze or other chemicals.
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
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