Installation Instructions
FeltBuster
®
High-Traction Synthetic Roofing Felt is a
UV-stabilized polypropylene underlayment designed to shed
water. FeltBuster
®
High-Traction Synthetic Roofing Felt
resists UV degradation for up to 90 days. Asphalt shingles
MUST be installed over FeltBuster
®
High-Traction Synthetic
Roofing Felt within 90 days.*
* NOTE: 90-day exposure period is based on standardized
testing concerning UV resistance. It is NOT related to how
long FeltBuster
®
High-Traction Synthetic Roofing Felt
can withstand water, snow, or wind. While FeltBuster
®
Roofing Felt is water resistant, it is NOT waterproof. DO
NOT USE FeltBuster
®
High-Traction Synthetic Roofing
Felt AS A TEMPORARY ROOF to protect property or
possessions.
CHECK FOR PROPER UNDER-DECK VENTILATION.
FeltBuster
®
High-Traction Synthetic Roofing Felt retards
moisture vapor movement. Humid air in the attic may
therefore condense as water beneath the FeltBuster
®
High-
Traction Synthetic Roofing Felt, resulting in deterioration of
the deck and growth of molds. A design professional must
ALWAYS address the potential for moisture entrapment,
excessive moisture build-up, and condensation. Moisture-
control solutions may include, but are not limited to, use of:
• a continuous vapor barrier in the ceiling
• soffit and ridge vents
• gable vents
• power vents
Be sure to review local building codes in your area for
ventilation requirements.
IMPORTANT: When fastening FeltBuster
®
High-Traction
Synthetic Roofing Felt, do not use nails or staples without
caps. Use only plastic cap, corrosion-resistant nails or
staples with plastic caps. Fasteners should be long enough
to penetrate at least 3/4" (19 mm) into wood decks or just
through plywood or OSB decks. Fasteners must be flush to
the deck and at a 90° angle to the roof deck.
PRECAUTIONS:
Always avoid scuffing. Normal walking on FeltBuster
®
High-Traction Synthetic Roofing Felt will not cause damage.
However, scuffing can damage FeltBuster
®
High-Traction
Synthetic Roofing Felt and compromise its performance.
Scuffing can be caused by twisting, kicking, or rubbing from
heavy shoes with weight pressing FeltBuster
®
High-Traction
Synthetic Roofing Felt against the deck.
If scuffing occurs, cover any scuffed areas with an
additional layer of FeltBuster
®
High-Traction Synthetic
Roofing Felt that exceeds the scuffed area by 6" (152 mm)
on each side. Adhere the additional layer of FeltBuster
®
High-Traction Synthetic Roofing Felt with a moisturecurable
polyurethane adhesive that meets or exceeds ASTM C557.
Follow the adhesive manufacturer’s instructions.
Cutting: Use a straight blade knife, scissors, or sharp hook
blade knife for cutting FeltBuster
®
High-Traction Synthetic
Roofing Felt.
SAFETY CONSIDERATIONS. As with all roofing projects:
• Be careful. Observe safe roofing practices and
requirements (OSHA). Use caution when walking or
standing on FeltBuster
®
High-Traction Synthetic Roofing
Felt. Wet and dusty conditions may make the surface
slippery. Failure to use proper safety gear and footwear
can result in serious injury.
• Placing materials on roof. Use roof jacks, toe boards, or
storage platforms secured to the underlying roof deck to
prevent slippage of stored roofing materials. Repair holes
in FeltBuster
®
High-Traction Synthetic Roofing Felt from
toe boards or roof jacks before installing primary roofing.
Repair small holes (<1/8" [3.2 mm] in diameter) with a
dab of asphalt roof cement or compatible sealant. Repair
larger damage following the instructions for scuffing
repair above.
ALL APPLICATIONS: FOLLOW STEPS 1–5
STEP 1: Prepare Deck Properly.
a) Clean deck. Remove debris and protruding
fasteners, which can damage FeltBuster
®
High-Traction Synthetic Roofing Felt and cause
leaks. Repair and replace any damaged or
rotted sections prior to installing FeltBuster
®
High-Traction Synthetic Roofing Felt.
b) Deck must be dry to prevent buckling of the
deck, which can result in deck movement and
damage the primary roof covering.
STEP 2: Install Leak Barrier.
a) Where a waterproof underlayment is needed,
install WeatherWatch
®
, StormGuard
®
, or other
GAF Leak Barrier at eaves, valleys, rakes, skylights,
dormers, and other vulnerable leak areas. See
appropriate GAF Leak Barrier published application
instructions for details.
b) Along the eaves and in the valleys, install the
Leak Barrier before installing FeltBuster
®
High-
Traction Synthetic Roofing Felt.
c) Along the rake, install FeltBuster
®
High-Traction
Synthetic Roofing Felt first, leaving at least 6"– 8"
(152 mm–203 mm) of the deck exposed along the
rake, and then install the Leak Barrier flush to the
rake edge and over the FeltBuster
®
High-Traction
Synthetic Roofing Felt.
d) In other areas, install the Leak Barrier over the
FeltBuster
®
High-Traction Synthetic Roofing Felt.
STEP 3: Lay Out FeltBuster
®
High-Traction Synthetic
Roofing Felt.
a) Apply FeltBuster
®
High-Traction Synthetic Roofing
Felt parallel to the eaves.
b) Install without wrinkles. Lay flat, cap nail flat. Do
NOT STRETCH during installation.
c) Over drip edge at eaves. Lay FeltBuster
®
High-
Traction Synthetic Roofing Felt over the eave metal
unless local building code requires otherwise or if
Leak Barrier is in place at eaves (see Figure 1).
d) Under drip edge at the rakes. Lay FeltBuster
®
High-Traction Synthetic Roofing Felt under the drip
edge at the rake to help prevent wind uplift at the
rake edge (see Figure 1).
STEP 4: STANDARD INSTALLATION INSTRUCTIONS
4:12 Slope Or More. Overlap FeltBuster
®
High-Traction
Synthetic Roofing Felt Before Fastening (see Figure 1)
a) Overlap 3" (76 mm) at side lap. Extend
FeltBuster
®
High-Traction Synthetic Roofing Felt 3"
(76 mm) over the preceding course. Use the line at
top of the printed grid to help align the 3" (76 mm)
overlap.
b) Overlap 6" (152 mm) at end lap. End laps should
overlap a minimum of 6" (152 mm) and be offset
from adjacent end laps by 3' (914 mm).
2:12 Slope To Less Than 4:12.* Install Double Coverage
(see Figure 2)
a) Overlap a full 25.5" (648 mm) over the
underlying course.
b) Continue up the roof using a 22.5" (572 mm)
exposure.
c) Overlap 6" (152 mm) at end lap seams and offset
from adjacent end laps by 3' (914 mm).
*Do Not Install On A Slope Less Than 2:12.
STEP 5: To Fasten FeltBuster
®
High-Traction Synthetic
Roofing Felt, use only plastic cap, corrosion-
resistant nails or staples with plastic caps.
a) Fasten side and end lap 12" (305 mm) on center
[use 6" (152 mm) on center for high wind areas].
b) Fasten in the field of the roll with two staggered
rows of fasteners spaced 24" (610 mm) on center
(use 12" [305 mm] on center for high wind areas).
SPECIAL INSTALLATION INSTRUCTIONS – FOR
MAXIMUM PROTECTION AGAINST EXPOSURE TO
RAIN/SNOW (ALL SLOPES 2:12 OR MORE)*
1) Side Lap Detail Must Be Taped.
a) For single coverage installations, increase side laps
to 6" (152 mm).
b) Fasten in accordance with Step 5 above.
c) Completely cover all side laps and all fasteners
with tape.
2) End Lap Detail Must Be Taped.
a) Overlap 12" (305 mm) at the end lap and fasten in
accordance with Step 5 above.
b) Completely cover all end laps and all fasteners.
3) Type of Tape. Use a butyl adhesive-based seam/
cover tape or a waterproof cloth duct tape. Follow the
tape manufacturer’s instructions. Note: The long-term
durability of these tapes varies by manufacturer and type.
Be sure to use a tape that is advertised to perform for the
full time that FeltBuster
®
High-Traction Synthetic Roofing
Felt will be exposed.
*NOTE: This product as installed may not be completely
waterproof even when these special instructions
are followed.
SPECIAL INSTALLATION INSTRUCTIONS –
IF ROOF MAY BE EXPOSED TO HIGH WINDS
1) Fasten side and end laps using 6" (152 mm) on center.
2) Fasten in the field of the roll with two staggered rows
of fasteners spaced 12" (305 mm) on center.
3) Always apply tape over all fasteners to help prevent
rain or snow from entering at the fasteners.
4) Leaking may result from exposed fasteners.
INSTALLATION INSTRUCTIONS FOR FELTBUSTER
®
HIGH-TRACTION SYNTHETIC ROOFING FELT
©2019 GAF 6/19 • #498
36"
(914 mm)
48"
(1.22 m)
48"
(1.22 m)
(572 mm)
22.5"
48"
(1.22 m)
(572 mm)
22.5"
Start with full 36" (914 mm) width Weather-
Watch
®
or StormGuard
®
Leak Barrier or a
full 48" (1.22 m) wide sheet of FeltBuster
®
High-Traction Synthetic Roofing Felt
(not shown).
Along rake, put
non-corrosive
metal drip edge
on top
of FeltBuster
®
High-Traction
Synthetic
Roofing Felt.
FeltBuster
®
High-Traction
Synthetic Roofing Felt
Note: Special application for low slopes is the same as drawing above except
side and end laps are taped.
* If leak barrier is required, use WeatherWatch
®
, StormGuard
®
, or other GAF
Leak Barrier.
* If leak barrier is required, use WeatherWatch
®
, StormGuard
®
, or other
GAF Leak Barrier.
Along eaves, put
leak barrier* on top
of non-corrosive
metal drip edge.
exposure
exposure
3' min.
3" side lap
6" (152 mm) end lap
(914 mm)
FeltBuster
®
High-Traction Synthetic
Roofing Felt
Along rake, put
non-corrosive
metal drip edge
on top of
FeltBuster
®
High-Traction
Synthetic
Roofing Felt.
Along eaves, put leak barrier* on top of non-corrosive
metal drip edge
between end laps
36"
(914 mm)
48"
(1.22 m)
48"
(1.22 m)
(572 mm)
22.5"
48"
(1.22 m)
(572 mm)
22.5"
Start with full 36" (914 mm) width Weather
-
Watch
®
or StormGuard
®
Leak Barrier or a
full 48" (1.22 m) wide sheet of FeltBuster
®
High-Traction Synthetic Roofing Felt
(not shown).
Along rake, put
non-corrosive
metal drip edge
on top
of FeltBuster
®
High-Traction
Synthetic
Roofing Felt.
FeltBuster
®
High-Traction
Synthetic Roofing Felt
Note: Special application for low slopes is the same as drawing above except
side and end laps are taped.
* If leak barrier is required, use WeatherWatch
®
, StormGuard
®
, or other GAF
Leak Barrier.
* If leak barrier is required, use WeatherWatch
®
, StormGuard
®
, or other
GAF Leak Barrier.
Along eaves, put
leak barrier* on top
of non-corrosive
metal drip edge.
exposure
exposure
3' min.
3" side lap
6" (152 mm) end lap
(914 mm)
FeltBuster
®
High-Traction Synthetic
Roofing Felt
Along rake, put
non-corrosive
metal drip edge
on top of
FeltBuster
®
High-Traction
Synthetic
Roofing Felt.
Along eaves, put leak barrier* on top of non-corrosive
metal drip edge
between end laps
Figure 1 – Standard Application For 4:12 Slope Or More
Figure 2 – Standard Application For Low Slopes
(2:12 Slope Up To But Not Including 4:12)