Specification

Purpose
This technical bulletin is intended as a resource for design professionals, to promote more uniform criteria for plan review and jobsite inspection of projects. This bulletin indicates an
acceptable method for achieving compliance with applicable codes and regulations, although other methods proposed by design professionals may be considered and adopted.
Code Compliance
The information presented is correct to the best of our knowledge at the date of issuance. Because codes continue to evolve, check with a local ocial prior to design and
installation. Other restrictions and exemptions may apply. This is only intended as a quick reference.
Disclaimer of Liability
Technical information contained herein is furnished without change or obligation and is given and accepted at recipient’s sole risk. Because conditions of use may vary and are beyond our control, Owens
Corning make no representation about, and it not responsible or liable for the accuracy or reliability of data associated with particular uses of any product described herein.
I. ASTM C1104 Standard Test Method for Determining the Water Vapor Sorption of Unfaced
Mineral Fiber Insulation
II. ASTM E96 Standard Test Methods for Water Vapor Transmission of Materials
III. https://cdn01.rockwool.com/siteassets/o2-rockwool/documentation/research/research-
summary/drainage-balance-testing-and-wall-comparison---research-summary.
pdf?f=20190918071302
IV. ASHRAE 160 Criteria for Moisture-Control Design Analysis in Building
V. ASTM E331 Standard Test Method for Water Penetration of Exterior Windows, Skylights,
Doors, and Curtain Walls by Uniform Static Air Pressure Difference
VI. For test summary, please see Results for Steel Stud, Results for Wood Stud, and Results
for CMU.
VII. ASTM C518 Standard Test Method for Steady-State Thermal Transmission Properties by
Means of the Heat Flow Meter Apparatus
Pub. No. 10024383. Printed in U.S.A. August 2020.
© 2020 Owens Corning. All Rights Reserved.
© 2020 Thermaber, Inc. All Rights Reserved.
The color PINK is a registered trademark of Owens Corning.
All Rights Reserved.
THERMAFIBER, INC
ONE OWENS CORNING PARKWAY
TOLEDO, OHIO, USA 43659
888-TFIBER1 [834-2371]
www.owenscorning.com/thermaber
Evaluating mineral wool’s thermal performance after sustained
moisture exposure
In the absence of relevant test standards, such as a spray rack method,
Owens Corning evaluated the thermal resiliency of Thermaber
®
RainBarrier
®
ci using ASTM C518
viii
. The thermal conductivity of the test
material was measured before and after being submerged in water for
a period of 88 hours. The test samples were removed from the water,
allowed to dry, and tested per ASTM C518. The test showed the samples
maintained their original thermal conductivity performance.
Thermaber
®
RainBarrier
®
delivers exceptional all around performance
All performance attributes – re performance, sustainability, acoustic
performance, and vapor permeability – should be considered when
selecting a ci product. While mineral wool’s reputation for outstanding
re resistance has long captured the market’s attention, the three
performance attributes described above illustrate mineral wool’s
hydrophobic properties. The ability to perform in wall cavities where
moisture is present makes mineral wool well suited as a ci for exterior
wall assemblies.
For more information, please visit www.owenscorning.com/thermaber
Always follow appropriate safety and industrial hygiene
practices during installation. Wear appropriate personal
protective equipment. Review SDS and literature before
specication and installation.
Mineral wool is inspiring new material testing suggestions
Traditionally, submersion tests have evaluated the water
resistance of insulating materials including polyisocyanurate,
expanded polystyrene, and extruded polystyrene. However,
there is no consensus on a standard test method, as each
product uses a different submersion test to demonstrate
water resistant properties.
POLYISO EPS XPS
ASTM Standard for
Product Type
ASTM C1289 ASTM C578 ASTM C578
Corresponding
Moisture Absorption
Test
ASTM C209/
ASTM C1763
ASTM C272 ASTM C272
Time Submerged 2 hours 24 hours 24 hours
Drain Time 10 minutes 0 minutes 0 minutes
“Passing” per
Product Standard
1% maximum*
2-4%
maximum**
0.03% maximum
*For Type I, Class 1 and Type 1, Class 2 Polyisocyanurate Products (most common
continuous insulations)
**For Types XI, I, VIII, II, & IX Expanded Polystyrene Products (most common
continuous insulations
However, while submersion tests may provide some
insight into the performance of insulation in applications
where sustained moisture is possible (i.e. a ooding
horizontal protected membrane plaza decks or foundation
applications) they are not relevant for above-grade
exterior walls, which are not expected to experience such
extreme conditions. In fact, other exterior wall assembly
components, such as cladding and exterior gypsum, are
not required to be evaluated via submersion testing and
many air and weather barrier system disclaimers state,
“not intended for use below grade”. Instead, membranes
resisting such extreme pressures are referred to as
“waterproong” and may be used below grade or in
low slope roong applications based on a series of
waterproong tests. If the weather barrier is not expected
to perform in this application, it is unreasonable to expect
such performance for an above-grade ci.
Regardless of your continuous insulation choice Owens
Corning advocates for consensus-backed testing that
adequately and accurately assesses the moisture
performance of all continuous insulation types in above
grade walls.