1. Pro-Master Roof Shield UDL™ must
be installed above properly ventilated
attic spaces (follow local building code) as it is considered
a vapor barrier.
Inspect, remove, and replace any defective roof sheeting.
The roof deck must be
clean, smooth, and dry before starting installation. A sharp
straight edge-cutting
blade is recommended to cut this material.
2. Install drip edge at the roof eave edges.
Pro-Master Roof Shield UDL™ is to
be laid horizontally (parallel to eave) with printed anti-slip
side up, starting at the
bottom of the lowest roof eave, with a 1.5" underlayment
overhang at the eave
covering the pre-installed eave drip edge. Overhang the
roof rake edge 1.5" and
cover the underlayment with a metal rake edge trim. Material
should be rolled
out evenly but not rolled tight or stretched. Lay loosely
over valleys to allow for
expansion and contraction due to temperature variation.
3.
Lap allowance – 3:12 pitch or greater
Horizontal: 4" minimum overlap of the higher course
over the lower course.
Vertical: 12" minimum overlap of the roll end
Lap allowance – 1.5:12 pitch
to <3:12
Horizontal: 6" minimum overlap of the higher course
over the lower course
Vertical: 20" minimum overlap of the roll end
4. ONLY USE 1" diameter plastic cap roofing
nails. Nail down squarely (90
degrees) into the deck to secure caps flush to the underlayment.
In normal wind
zones the nails should be driven at 6.0" O.C. (on center)
on both head and end
laps. Fasten the field area in the middle of the roll a
minimum of 24" O.C. in normal
wind zones. In high wind zones or coastal applications increase
the fastening
rate to 4.0" O.C. on head and end laps. The field area
should be fastened at
12" O.C. minimum. Plastic capped nails may be hand
or machine applied.
Optional lap method at first head
lap for enhanced protection in snow/ice areas:
Install first horizontal course at eave with 1.5"
overhanging bottom drip edge. Place a few cap nails 4"
from top edge to hold in place. Nail all other areas at
other edges and field nail per instructions. Place another
layer with the print side down over the first layer. Fold
over the 2 layers 2" at the top and nail every 6
inches in the middle of the fold area to secure the head
lap. Lift the loose material and position as the second
horizontal course. Nail all edges and field areas as instructed.
5. Overlap vertical roll end by 12" or 20" depending
on pitch. Overlap successive vertical courses by 4"
with the higher course lapping over the lower course, and
by 6" on roofs with slopes of less than 3:12. Lap at
least 6" over the ridge.
6. Use ASTM D4586 Type 1, Federal Spec SS153
Type 1 (Asbestos Free) plastic roofing cement on seams or
joints that require sealant or adhesive. Butyl rubber roofing
tape may be also used to seal lap seams. When the underlayment
will not be covered with roofing material for a prolonged
period or it will be exposed to wind driven rain, the laps
should be sealed with cement or taped. It should be nailed
in accordance with the recommendation for high wind areas.
7. Install a single vertical length of Pro-Master
Roof Shield UDL™ centrally
over hips and down valleys before weaving horizontal underlayment
across the
valleys and hips. This also applies to metal hip or valley
flashings that may be
specified.
8. Install underlayment a minimum of 6 inches
up roof protrusions or vertical
abutments. Seal with adhesive sealant or tape as described
in section 6. Install
final flashing material.
9. When underlayment is to be covered immediately
with battens, it can be
secured with a minimum of fasteners to hold it in place
while the battens are
installed. Care should be exercised to place the 1"
diameter plastic cap nails in
an area that will not interfere or be covered with the batten
strips.
10. Determine local building code requirements
and check to ensure compliance
of methods and materials required for the job.
