Insulation Overview
** Not for Distribution Outside NSF/UL 440 **
Stan Wolfersberger
August 2013
Insulation Overview for NSF/UL 440
• Start with some basics:
– What insulation products do
– Types of insulation
– Performance expectations for insulation
– Where insulation is used in buildings
• Insulation and Emissions: It Gets Complicated
– How a packed wall cavity behaves differently than insulation in a
dynamic chamber
– Thermal insulation, a temperature gradient is almost always
present
– Most insulation products are installed behind other products
– Simple models do not reflect in-use reality in most cases
What Insulation Products Do
• Thermal insulation is critical component for energy-efficient
buildings of all types (walls, ceiling/roof, slab, foundations,
etc. etc.).
– From NAIMA website, “The definition of “insulate” as it
relates to the flow of heat in homes, buildings and processes
means to slow or retard the flow of heat from warmer to colder
areas. This happens by surrounding the area with a material
with low thermal conductance – such as thermal insulation.”
• Building code often mandates the minimum required levels
of thermal insulation
– Note that adoption of the model energy code by states & local
governments may lag by several years from the most current
edition for Residential structures.
What Insulation Products Do
• Besides the “typical” thermal insulation uses in
buildings, commercial/industrial applications can
include high-temperature equipment insulation,
cryogenic equipment insulation, and so on.
• Acoustical applications of insulation are also
widespread; most thermal insulation types also offer
acoustic benefits.
• Certain types of insulation may be used as fire blocking,
fire safing, etc.
• Insulation can provide condensation control.
• Some types of insulation may be effective air barriers.
Types of Insulation
• Fibrous glass, mineral wool (rock wool, slag wool)
• Cellulosic materials
• Rigid foams (Expanded Polystyrene, Extruded Polystyrene,
Polyisocyanurate, Polyurethane, etc.)
• Flexible foams (Polyethylene, etc.)
• Spray foams (spray-in-place foams dominated by spray
polyurethane foams, can be open or closed cell)
• Other (foamed glass/cellular glass, aerogels, perlite, vacuum
panels, etc.)
Performance Expectations for Insulation – ASTM C665,
Mineral Fiber Blanket Thermal Insulation for Light Frame
Construction and Manufactured Housing
• Includes the following material property requirements:
– Thermal resistance (thermal conductivity aka R value)
– Surface burning characteristics (flame spread and smoke
developed)
– Critical radiant flux (critical radiant flux-flame propagation
resistance)
– Water Vapor Permeance (for products faced with a vapor
barrier)
– Water Vapor Sorption
– Odor Emission
– Corrosiveness (steel, copper, aluminum)
– Fungi Resistance (5 strains of fungus, compared to white birch
or southern pine control)
Other Expectations – Batt Insulation Example
• Contractor and installer requirements can include:
– Low dust
– Stiffness of batts
– Quick recovery to label thickness after opening compressed
packages
– Parting strength
– Value (Cost $$ vs. Benefit)
• Federal Trade Commission, “Labeling and Advertising of
Home Insulation: Trade Regulation Rule”, 16 CFR Part 460,
covers R-value tolerances, acceptable test methods for Rvalue, product labeling, etc.
Each Type of Insulation Typically Has its Own
Consensus Standard of Required Properties
•ASTM C739, Cellulosic Fiber Loose-Fill
Thermal Insulation
•ASTM C1289, Faced Rigid Cellular
Polyisocyanurate Thermal Insulation Board
•ASTM C578, Rigid, Cellular Polystyrene
Thermal Insulation
•ASTM C1029, Spray-Applied Rigid Cellular
Polyurethane Foam Thermal Insulation
Commercial Buildings & Insulation
Single-Family House & Insulation
Insulation in Wall Cavities
Insulation Behavior in a Wall Cavity –
Static Chamber Tests Give Insight
Explore Loading Impact on Product
Emissions with Static Chamber Tests
Typical Data – Emissions Go Down as Loading Goes
Up (Formaldehyde, Desiccator Test)
Loading, m2/m3
Emissions, ug/m2-hr
Product A
0.49
93.1
(~ 9:1 ratio from low to
high loading results)
1.78
24.8
2.83
10.6
Product B
0.49
68.2
(~ 3:1 ratio from low to
high loading results)
1.78
30.5
2.83
27.2
Understanding the Loading Effect
Loading Effect Has Also Been
Observed in Dynamic Chamber Tests
• Work done at Oak Ridge National Laboratory for CPSC by
Matthews and Westley (see “References – Insulation and
Related Products SJW 2013”).
• Also see work by Pickrell, et al. for CPSC, both static
chamber and dynamic chamber tests. This includes the
impact of testing products together. Loading impact studied
for wood products in static chamber tests (see “References –
Insulation and Related Products SJW 2013”).
Thermal Insulation – Almost Always a
Temperature Gradient Across Product
Most Insulation Products Are Not Directly Exposed –
Behind Other Products
Some “System” tests have been run, but
they over-simply real-life situation
• Simulated wall stud cavity tests, with
metal or wood studs, insulation,
with/without drywall, vapor barrier,
paint using dynamic chambers.
• These tests show that having products
over the insulation reduces emissions.
• However, there was no temperature
gradient, no path for emissions to go
“outside” vs. in, no differential
pressure driving force, etc.
• Trying to simulate actual in-use
emissions would overly complicate
the test procedure.
Understand the Limitations of the Simple
Models – Outside the Building Interior, They
May Not Reflect Reality
Vapor Barriers May be Integral
Components of Installed Insulation
• Pipe insulation example
• Manufacturers provide
accessory sealing tapes,
butt strips, mastic, etc. so
the insulation system is
protected by a vapor
barrier
• Such products may need
more specific sample
prep/testing instructions
if dynamic chamber tests
are to be representative of
installed products.
Some Key Take-Aways - Insulation
• Dynamic chamber testing can be used to determine emissions from
insulation products; however, the simple models in use are
generally overly conservative and do not reflect in-use dynamics.
• Once you go outside the interior space, application of simple
models may produce misleading predictions of indoor air quality
impact of products like insulation.
• When there are multiple models which differ in modeling
assumptions, then the required emissions for insulation can differ
(see my previous examples from CA SM V1.1 for E&P TG meeting).
• Simple model(s) are Ok for taking dynamic chamber emissions
results and producing predicted air concentrations to see if a
product meets low-emitting criteria. But keep in mind their
purpose – to compare products, not to predict actual VOC
concentrations inside a real building.
Additional Sources of Information
• Trade Associations
– North American Insulation Manufacturers Organization
– Cellulose Insulation Manufacturers Organization
– Extruded Polystyrene Foam Association
– Spray Polyurethane Foam Alliance
– Expanded Polystyrene Industry Alliance
• Building Science
– Manufacturer’s or Trade Association websites
– Building Science Consultants, Researchers including U.S. National
Labs such as Oak Ridge, Berkeley, as well as private and non-U.S.
labs (Building Science Corp; Fraunhofer Institute for Building
Physics; etc.) as well as organizations such as The Energy &
Environmental Building Alliance.
Thank You!
Any Questions???
*** Reminder, not for distribution outside NSF/UL 440 ***