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Integrating Systems for Green Design Research Report - 0504 Oct-2005 Betsy Pettit, AIA
Abstract: The effects of building development on the environment are at the most basic level about durability. Building a house or community is really about the durability of people, the durability of buildings, and the durability of the planet. Durability is really another way of expressing the concept of sustainability to the building community.
Integrating Systems for Green Design Betsy Pettit, AIA Building Science Corporation www.buildingscience.com
EEBA, Colorado Springs, October 2005 RR-0504: Integrating Systems for Green Design
What makes good building design? Firmness, commodity, and delight? "Well building hath three conditions: firmness, commodity, and delight." This quote is taken from Sir Henry Wotton's version of 1624, and is a plain and accurate translation of the passage in Vitruvius
Homo Vitruvianus By Leonardo da Vinci RR-0504: Integrating Systems for Green Design
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Vitruvius also said,
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”These are properly designed, when due regard is had to the country and climate in which they are erected. For the method of building which is suited to Egypt would be very improper in Spain, and that in use in Pontus would be absurd at Rome: so in other parts of the world a style suitable to one climate, would be very unsuitable to another: for one part of the world is under the sun's course, another is distant from it, and another, between the two, is temperate”.
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Marcus Vitruvius Pollio c. 90 – 20 B.C.E.
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Durability
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Goals
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Priorities
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Integrating Systems for (green) building design Leak-free thermally efficient enclosure systems – Intentional openings for exhaust of pollutants – Intentional openings for outside air intake – Control of materials intentionally brought into building
Right-sized integrated mechanical systems – Efficient distribution of conditioned air – Efficient removal of pollutants • Efficient filtration • Efficient introduction of outside air for dilution
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Budget = Form (dictates choices for enclosure design) • • • • •
Structure Foundation type Roof design Cladding type Energy collection systems
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Budget = Sophistication (dictates choices for mechanical systems) • Mechanical equipment efficiency, motors, burning fuels, moving air • Ability to clean, distribute, recover energy, dehumidify • Collecting and using site generated energy
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System Integration Improvements in the enclosure Downsize the mechanical equipment __________________________ Better Performance, lower energy bills
(+) (-) =
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Type of Occupancy dictates choices for enclosure & mechanical systems
• Comfort of Occupants • Indoor Air Quality • Energy Efficiency
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Comfort, indoor air quality, energy efficiency, durability all require… • Leak-free buildings with high R-value enclosures • Source control of pollutants • Heated or cooled air delivered in consistent manner to occupied space • Outside air change with mixing 13 RR-0504: Integrating Systems for Green Design
Provide a Durability Plan 9 Foundation moisture control strategies 9 Wall moisture control strategies 9 Roof moisture control strategies 9 Interior “wet� rooms moisture control strategies 9 Mechanical systems moisture control strategies 14 RR-0504: Integrating Systems for Green Design
In order to control the air Enclose the air
© buil – An enclosure is constructed d ings – This enclosure provides closure cien for all six sides© of the cube c e b .com uild – Openings in the enclosure ings should be intentional c i enc • Doors, Windows, Exhaust vents, © e.co buil Outside Air Intake ding m scie nce .com 15
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Establish Enclosure Tightness Same metric everywhere
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Between 2 and 3© ach@ 50 Pa
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– Leakier than the Canadian R-2000 – Tighter than the typical American home – Achievable- Over 100,000 built to this standard under this program
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Air brought into the the home can be – – – – – –
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According to ASHRAE 62.2 • The same amount everywhere, every climate • Big houses need more air than smaller houses • Selecting materials does not affect the rates under current thinking
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Bringing in Outside Air Can Be Expensive in Terms of Energy
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• We do not want to bring in more than we need •
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Fan Recycling Application Activates the central system fan for a © bubeen selectable ON time if it has ildin inactive for a selectable OFF time gsc i – Improved comfort control by enc © e.co periodic mixing bui
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Control of Moisture Pollutant • In cold climates, it is interior moisture generation – Air change with dryer outside air
• In hot humid climates, it is exterior moisture – Dehumidification through cooling or dedicated dehumidifiers
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Ducts in Conditioned Space - Mixed Dry Climate
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Ducts in Conditioned Space - Hot Dry Climate
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Cold Climate - Ohio
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Cold Climate - Ohio
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Cold Climate Integration
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Cold Climate Integration
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Cold Climate - Cleveland, Ohio
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Cold - Details
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Cold - Details
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Energy Efficiency
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• Structure only where ingsc ienc needed ©
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• Blown insulations that fill the entire void
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Cold Climate - Details
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Energy Efficiency - Ventilation
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i n – Air tight houses need gsc i enc controlled air change ©b e .com u – ERV’s can deliver savings, ildin but watch out for their gsc electricity consumption ien c e.co – Central Fan integrated m system among the simplest
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Cold Climate - Carbondale, Colorado
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Energy Efficiency Heating/Cooling - Gas/Electric ©
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Very Cold - Details
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Very Cold - Details
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Very Cold - Details
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Energy Efficiency ©Hot Water - Gas, Tankless
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Cold Climate - Details
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Cold Climate DAS Construction, Cleveland EcoVillage, OH
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Building America Toward Zero Energy Homes - Cleveland Cleveland EcoVillage Townhouses Project Highlights (1666 sf House)
Energy Performance
Building Enclosure
R-19 2x6 24 oc + R-5 walls R-38 vented attic Low E windows (U-0.36, SHGC-0.45) R-10: 2" XPS on basement walls R-8 2" EPS under entire slab BSC BA Airtightness (2.5 ins/100 sf)
Heating Cooling Hot water Light/Appl Sub-total
Mechanical
90%+ AFUE Sealed-Combustion Furnace 12 SEER Air Conditioner Split System 0.59 EF Power-Direct Vent Water Heater Fan cycler ventilation system
Solar Site Collection
3.8 kW Peak PV system
MMBtu/yr 38.6 5.4 21.4 n/c 65.4
Solar PV Collection
-13.5
Total Predicted Use
51.9
MEC 95 Predicted Use
130.8
% Savings vs MEC 95
60%
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Foundation Detail
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Division 6: Wood ©- bFSC-certified, focus on engineered wood uild products/efficient framing
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Cold Climate © b- Loveland, Colorado - McStain u ildEnergy Site Generated in - Heat , Hot Water
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Building America Toward Zero Energy Home Projects McStain Enterprises Discovery House (Boulder, CO) Project Highlights (2512 sf House)
Energy Performance
Building Enclosure
Walls: 2x6 24 oc R-19 + R-4 insul. shth. R-44 blown cellulose at ceiling Solar Low E windows (U-0.35, SHGC-0.34) Insulated foundation (R-11 wall, R-6 floor) BSC BA Airtightness (2.5 ins/100 sf)
Heating Cooling Hot water Light/Appl Sub-total
Mechanical
High Efficiency (92% AFUE, 20 EER) Combo system ASHRAE 62.2 ventilation by HRV Flourescent lighting
Solar SHW Collection
Solar Site Collection
96 sf drain back SHW system Integrated with heating system
MMBtu/yr 100.2 0.7 31.0 55.2 187.1 -27.2
Total Predicted Use
159.9
Benchmark Predicted Use
283.0
% Savings vs BA Benchmark
44%
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Site Generated Energy - Heat , Hot Water ©
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© bEnclosure Design uild ings cien ©b c e.co uild m ings cien ©b c e.co uild m ings cien ce.c om 54 RR-0504: Integrating Systems for Green Design
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Building America Toward Zero Energy Home Projects CORE/Fenton Construction: Blue Creek Ranch: Next Generation Homestead Houses Project Highlights (1256 sf House)
Energy Performance
Building Enclosure
R-19 2x6 24 oc OVE w. damp-spray cellulose R-56 blown cellulose (14" minimum) Low E windows (U-0.36, SHGC-0.48) Conditioned Crawl (R-10) BSC BA Airtightness (2.5 ins/100 sf)
Heating Cooling Hot water Light/Appl Sub-total
Mechanical
High Efficiency (92% AFUE) Condensing Boiler Integrated DHW / SHW / space heating system ASHRAE 62.2 ventilation by HRV Flourescent lighting
Solar PV Collection Solar SHW Collection Total Predicted Use
52 sf glycol solar thermal system 1.68 kW Peak PV system
% Savings vs BA Benchmark
Solar Site Collection
MMBtu/yr 66.8 0.0 28.0 44.6 139.4 -21.8 -22.8 94.7
Benchmark Predicted Use
173.0
45%
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© bClimate - Barley Phieffer Design Mixed Humid u ildin Homes - Dallas Anderson Sargent g ©b
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Building America Zero Energy Home Projects- Dallas Anderson Sargent Homes: Dallas Parade of Homes Project Highlights (3814 sf House)
Energy Performance
Building Enclosure
Durisol walls (R-14) Spray foam unvented attic (R-30) Solar Low E windows (U-0.38, SHGC-0.29) Insulated Radiant Slab (R-5) BSC BA Airtightness (2.5 ins/100 sf)
Heating Cooling Hot water Light/Appl Sub-total
Mechanical
High Efficiency (9 HSPF, 13 SEER) Chilled Water Heat Pump Tankless HWH back-up (0.82EF) ASHRAE 62.2 ventilation Flourescent lighting
Solar PV Collection Solar SHW Collection Total Predicted Use
64 sf SHW system 8.12 kW Peak PV system
% Savings vs BA Benchmark
Solar Site Collection
MMBtu/yr 17.4 18.2 19.8 66.5 121.8 -82.5 -11.8 27.5
Benchmark Predicted Use
329.0
92%
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© Climate Mixed Humid - Ideal Homes, - Oklahoma b uild
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Building America Zero Energy Home Projects - Oklahoma Ideal Homes, OKC, OK Project Highlights (1644 sf House) Building Enclosure
Mechanical
Solar Site Collection
Energy Performance
Walls: 2x6 24 oc R-19 + R-3 insul. shth. R-38 blown cellulose at ceiling Radiant barrier roof sheathing Solar Low E windows (U-0.39, SHGC-0.31) Insulated Slab edge (R-3) BSC BA Airtightness (2.5 ins/100 sf) High Efficiency (4 COP, 20 EER) Ground Source Heat Pump Tankless HWH (0.82EF) ASHRAE 62.2 ventilation by ERV Flourescent lighting 5.3 kW Peak PV system
Heating Cooling Hot water Light/Appl Sub-total
MMBtu/yr 26.8 11.6 14.5 54.5 107.4
Solar PV Collection
-82.5
Total Predicted Use
24.9
Benchmark Predicted Use
230.0
% Savings vs BA Benchmark
89%
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Energy Efficiency Heating/Cooling - Electric High efficiency ground source heat pump (GSHP) – Moves heat to & from the ground, instead of burning stuff – Year ‘round heating and cooling at high efficiency – No combustion risks – Option of de-superheater hot water system
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Building America Toward Zero Energy Homes- South Georgia GA DNR Admin Building SIPS Cottage (Fargo, GA) Project Highlights (1880 sf House)
Energy Performance
Building Enclosure
SIPS walls (R-23) & roof (R-38) Solar Low E windows (U-0.33, SHGC-0.33) Conditioned Insulated (R-8) crawl BSC BA Airtightness (2.5 ins/100 sf)
Heating Cooling Hot water Light/Appl Sub-total
Mechanical
High Efficiency (9 HSPF, 13 SEER) Air Source Heat Pump Marathon Electric HWH (0.94EF) Stand alone dehumidifier ASHRAE 62.2 ventilation Flourescent lighting
Solar Site Collection
2.9 kW Peak PV system
MMBtu/yr 16.5 26.9 16.7 50.6 110.7
Solar PV Collection Total Predicted Use
-48.9 61.8
Benchmark Predicted Use
180.0
% Savings vs BA Benchmark
66%
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Energy©Efficiency - Hot Water, Electric
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Building © Shell: Strategies Used
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Integrating Systems for Green Design
About this Report This presentation was presented at the 2005 EEBA Conference in Colorado Springs, Colorado. About the Author Betsy Pettit, FAIA, is the president of Building Science Corporation and is a registered architect with over 25 years of professional experience. Ms. Pettit has contributed to many procedural and technical manuals and papers published in building journals and elsewhere. More information about Betsy Pettit can be found at www.buildingscienceconsulting.com.
Direct all correspondence to: Building Science Corporation, 30 Forest Street, Somerville, MA 02143.
Limits of Liability and Disclaimer of Warranty: Building Science documents are intended for professionals. The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered. The author and publisher make no warranty of any kind, expressed or implied, with regard to the information contained in this article. The information presented in this article must be used with care by professionals who understand the implications of what they are doing. If professional advice or other expert assistance is required, the services of a competent professional shall be sought. The author and publisher shall not be liable in the event of incidental or consequential damages in connection with, or arising from, the use of the information contained within this Building Science document.