Themax basement installCutting
THERMAX™insulation prod-
ucts may be cut with a straight
edge and utility knife or with
a small handsaw. See Figures
1a and 1b.
Figure 1a
Materials Checklist
To install THERMAX™
Sheathing or THERMAX™
White Finish insulation, you
will need:
• Utility knife or small
handsaw
• Straight edge
• Safety glasses/goggles and
gloves
• Ventilation or respiratory
protection for application
of polyurethane foam
sealant
• Measuring tape
• Pencil
• Construction-grade
adhesive such as
ENERBOND™MH or SF
Polyurethane Adhesive
• THERMAX
™aluminum foil
or white foil tape (for
Option 1)
• Mechanical fasteners
(optional for Option 1)
• Squeegee or soft paint
roller (for Option 1)
• PVC interlock joint closure
system (for Option 2)
• Polyurethane-compatible
construction-grade caulk/
sealant(for Option 2)
• Polyisocyanurate-
compatible insulating
foam sealant such as
GREAT STUFF™Pro Gaps
& Cracks
Before installing THERMAX
insulation on the interior
basement wall, be sure there
are no leaks or structural
cracks in the wall. THERMAX
products insulate the base-
ment wall; they do not stop
water leakage.
®™Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow
*See International Code Council National Evaluation Services Report NER-681.new homes/remodelingTHERMAX™Sheathing and
THERMAX™White Finish (WF)
insulation offer two quick and
easy options to insulate base-
ment walls. Lightweight and
easy to install, both products
are ideally suited for exposed
basement applications, whether
the desired result is a semi-
finished or finished appearance.
THERMAX Sheathing and
THERMAX White Finish are non-
structural, rigid boards consisting
of a glass-fiber-reinforced poly-
isocyanurate foam core with
solid aluminum facers on both
sides. The exposed surface of
THERMAX Sheathing is reflective
foil, perfect for use in areas such
as a laundry room or storage
space. THERMAX White Finish
insulation features an embossed
white acrylic-coated aluminum
facer on its exposed surface,
for a clean, finished wall that
is durable and washable.
THERMAX products can be
left exposed to the interior
without a thermal barrier in
most applications.* THERMAX
insulation products are Factory
Mutual approved as “Wall-
Ceiling Construction, FM
Approvals Standard FM 4880,
Metal Faced – Class 1 Fire Rated
to a max. 30 ft High.”
United StatesINSTALLATION INFORMATION RESIDENTIAL
INSTALLATION PROCEDURES
FOR THERMAX™INSULATIONS
Exposed Basement Applications
foundationsslabs
sillsatticswallsceilin
g
s
roofs
Figure 1b
Installation
THERMAX™insulations may be
attached directly to the basement
wall with construction-grade
adhesive or with the PVC inter-
lock joint closure system. Both
installation methods offer a
quick and easy alternative to
using studs, batt insulation and
drywall.
OPTION 1: ADHERE DIRECTLY
TO WALL
1. Provide proper ventilation
and wear gloves and eye
protection.
2. Apply heavy beads (min.
bead size 3/8") of ENERBOND™
MH or SF Polyurethane
Adhesive or appropriate
construction-grade adhesive
to the wall (Figure 2).Note:
Follow adhesive manufacturer
recommendations for
application pressure and cure
times for proper adhesion to
masonry walls.
2
INSTALLATION INFORMATION
3. Press insulation board
against the wall and butt
board edges tightly together
(Figure 3). Apply pressure to
board until the adhesive is
set. (Optional: Attach
mechanical fasteners to the
top and bottom of the board
to hold it in place until the
adhesive has set.)
4. For additional insulation
value and protection against
air infiltration, apply a small
bead of GREAT STUFF™Pro
Gaps & Cracks along board
seams. Take care that foam
does not get on insulation
facer during application.
Allow foam to fully cure,
then trim excess with a
serrated knife.
5. Cover seams between insula-
tion boards with aluminum
or white foil tape (Figure 4).
Before applying tape, wipe
the application area with a
damp cloth to remove foam
dust. Allow surface to air dry.
Use a squeegee or soft paint
roller to press the tape firmly
to the joint. Cut tape with a
knife or scissors. Do not tear
tape.
Figure 2
®™Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow
OPTION 2: PVC INTERLOCK
JOINT CLOSURE
For additional moisture control
and a more finished appearance
when insulating with THERMAX™
White Finish insulation, use
the PVC interlock joint closure
system. The PVC interlock
joint closure system is com-
posed of a 2" wide PVC base
strip that is attached to the
wall at vertical joint locations
and a top “T” section that
snaps into the base, holding
the insulation boards to the
wall. The top “T” sections are
available in sizes to accommo-
date board thicknesses of 1",
1.5" and 2". Select the correct
top “T” section size for your
application. Both the PVC base
strip and top “T” sections are
sold in 10' lengths.
1. Measure and mark vertical
lines for the placement of
the PVC base strips. Space
the PVC base strips for the
correct width of the insula-
tion board (Figure 5). Allow
1/8" between the insulation
boards to accommodate the
width of the PVC base strip.
2. Fasten PVC base strip to con-
crete or masonry wall every
12" with a pneumatic nailer
or equivalent (Figure 6).
Figure 5
Figure 6
Figure 3
Figure 4
3
Additional
Protection
Against Air
and Moisture
Use GREAT STUFF™Pro Gaps &
Cracks to seal gaps, cracks and
joints as well as to insulate the
area between floor joists along
the sill plate (Figures 11 and 12).
Note: GREAT STUFF™Pro foam
sealant products cannot be
removed from THERMAX™
White Finish insulation. Use tape
or protective film to protect
board surface from overspray.
Figure 10
®™Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow
3. Provide proper ventilation
and wear gloves and eye
protection.
4. Apply beads of ENERBOND™
MH or SF Polyurethane
Adhesive or appropriate con-
struction-grade adhesive to
the wall every 16" between
PVC base strips (Figure 7).
5. Press insulation board firmly
into position between the
PVC base strips (Figure 8).
Figure 8
7. Figure 10 shows three differ-
ent options for finishing at
corners: butting two panels
against one another, using
the PVC Clip Strip or using
the J-channel edge closure.
The method chosen depends
on the desired finished look.Figure 11
6. Apply a continuous bead of
construction-grade caulk/
sealant along the vertical
edges of the insulation
boards, then position and
press a PVC top “T” section
in the PVC base strip until it
snaps into place (Figure 9).
Figure 9
Figure 12
Figure 7
Utilities
Installation
Electrical and plumbing
utilities can be easily installed
behind or within the insulation
board. Cut openings in the back
side of the insulation board for
electrical boxes and access to
plumbing fixtures and other
utilities (Figures 13 and 14).
for Painting
If desired, THERMAX™
Sheathing and THERMAX™
White Finish insulation may
be painted after installation
and taping of joints. Visit the
online Answer Center at
www.insulateyourhome.com/
thermax for more specific
recommendations to paint
THERMAX insulations.
Recommendations
INSTALLATION INFORMATION
Figure 13
Figure 14
Form No. 179-07260-0506P&M
IN THE U.S.:
• For Technical Information: 1-866-583-BLUE (2583)
• For Sales Information: 1-800-232-2436
NOTICE: No freedom from any patent owned by Dow or others is to be inferred. Because use conditions and applicable laws may differ from one location to another and may change with time, Customer
is responsible for determining whether products and the information in this document are appropriate for Customer’s use and for ensuring that Customer’s workplace and disposal practices are in
compliance with applicable laws and other government enactments. Dow assumes no obligation or liability for the information in this document. NO WARRANTIES ARE GIVEN; ALL IMPLIED WARRANTIES
OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY EXCLUDED.
THERMAX products should be used only in strict accordance with product application instructions. THERMAX products, when used in a building containing combustible materials, may contribute to the
spread of fire. For more information, consult MSDS and/or call Dow at 1-866-583-BLUE (2583). In an emergency, call 1-989-636-4400.
WARNING: THERMAX insulation does not constitute a working walkable surface or qualify as a fall protection product.
Building and/or construction practices unrelated to insulation could greatly affect moisture and the potential for mold formation. No material supplier including Dow can give assurance that mold will not
develop in any specific system.
THE DOW CHEMICAL COMPANY
• Building & Construction • 200 Larkin • Midland, MI 48674 • www.insulateyourhome.com/thermax
Printed in U.S.A.®™Trademark of The Dow Chemical Company
(“Dow”) or an affiliated company of Dow
Habitat for Humanity is a registered service mark owned by Habitat for Humanity International
Insulation, when installed
according to ENERGY STAR
guidelines, can save energy.
www.energystar.gov