icf blower door aug 2010
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7/21/2019 ICF Blower Door Aug 2010
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Blower Door Testing of Insulated Concrete Form (ICF) HomesMarzena Kasia FYDRYCH1, Michael STREET1,2
1Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, 02139 Cambridge, United States. 2 Morehouse College ,Atlanta, [email protected]
OBJECTIVE
Evaluate the air tightness of Insulated Concrete Form single-family
homes
MOTIVATION
B
CONCRETE
SUSTAINABILITY
HUB
IMPACT
ACKNOWLEDGEMENTS
This work has been supported by the Concrete Sustainability
Hub at MIT, with sponsorship provided by the Portland
Cement Association (PCA) and the RMC Research &
Education Foundation.
REFERENCES
[1] ASTM E1827-96 Determining Airtightness of Buildings Using an Orifice Blower Door
[2] ASTM E779-03 Standard Test Method for Determining Air Leakage Rate by Fan
Pressurization
[3] ASHRAE 438RP-92 Evaluation of the Techniques for the Measurement of Air Leakage of
Building Components,D.G.Colliver, W.E.Murphy, W.Sun
[4] ASHRAE Fundamentals - 2009
• Infiltration of air through the building envelope is often a major variable
in a system’s heating and cooling loads.
• Air will flow through building elements such as walls, roofs, windows,
doors and bathroom and kitchen vents. The choice of wall materials,
windows and doors and the quality of construction affect the total
leakage area of the envelope. Air flow will depend on an envelope’s
leakage area and the pressures generated by winds and buoyancy
forces associated with indoor-outdoor temperature differences. These
natural forces vary with building location.
• ICF walls consist of a
solid, continuous and
seamless unit that
suggests tighter
construction than framedwalls.
• Infiltration is very difficult
to predict and is better
estimated with house-
specific air tightness tests.
Inadequate field tests have
been done to evaluate the
general potential for
reduced air infiltration of
ICF homes.
MIT in cooperation
with Concrete Industry
personnel has
scheduled airtightness tests of 40
ICF houses across
the United States.
To date,15 blower door experiments have been carried out in:
• Mississippi – 10 houses
• Florida – 2 houses
• Connecticut – 2 houses
• New Hampshire – 1 house
House floor area has varied from 800 to 7300ft2
METHODOLOGY
BLOWER DOOR TEST
Blower door tests have been
performed by certified home auditorsaccording to ASTM E1827-96[1] or
ASTM E779-03[2] using the
Minneapolis Blower Door with
TECTITE software.
Blower Door Methodology[3]
• A powerful variable speed fan is
placed in an opening in the building
envelope
• The air is blown into (pressurization)
or out of (depressurization) the building.
• A uniform, artificial, static pressure is
imposed across the entire building
envelope and the amount of air being
moved by the fan to create this
pressure differential is determined.
• The air flow rate through the fan is
usually determined from: a)
measurements of the pressure drop
across a known flow restriction, or b)
the fan rotational speed and a
calibration curve.
Building Data
1782.5 ft2 floor area
14082.1 ft3 volume
3962 ft2 exposed surface
KEY FINDINGS
Construction Classification Based on Unit Leakage Area[4]
• Tightness of tested ICF houses varied from good to tight.
• Mean air tightness was 0.016in2 /ft2 (1.05cm2 /m2)
Leakage area normalized by exposed surface area is a usefulmetric for evaluating air tightness, based on ASHRAE ratings.
• Measurement-based air tightness metrics indicate that IC F
houses are subject to lower amounts of uncontrolled
outdoor airflow than typical production housing.
• Tighter construction facilitates the use of mechanical
ventilation with heat recovery for low-cost and low-
environmental-impact building ventilation.
• Air tightness measurements allow us to quantify energy use
and carbon emissions associated with air leakage for
houses in different climate regions using building energy
simulation programs.
Building Leakage Curve
Airflow at 50 Pascals
Calculations
Air Change per Hour
Test Data Flow at 4Pa
AL total leakage area of the building
Unit leakage area
(per ft2 of exposed surface)
Example Blower Door Data