Kingspan Insulation
Kingspan Group

P Series Fanfold Underlayment

P Series Fanfold Underlayment header

When you need fundamental performance in an extruded polystyrene (XPS) siding underlayment, choose the P Series. Flexible plastic facers on both sides enhance durability, while an optional reflective facer enhances thermal performance. Both types of facers are perforated to allow moisture vapor to escape. A cut-and-fold hinge design ensures the underlayment lays flat.

TYPICAL PHYSICAL PROPERTIES
Property Test Method P1450 FP1450
R-Value1
(°F-ft²-h/Btu)
ASTM C 518
(@75°F Mean Temperature)
1.0 3.0
Water Vapor Permanence
(perm)
ASTM E 96
Procedure A
1.7 1.7
Water Absorption
(Max. % by Volume)
ASTM C 272 2.0 2.0
Compressive Strength
(psi @ 10% deflection)
ASTM D 1621 12 12
Fire Characteristics2
Flame Spread
Smoke Development
ASTM
E 84/UL 723

25
250

25
250
DIMENSIONS / PACKAGING
P1450 FP1450
Length3 50' 50'
Width3 4' 4'
Nominal Thickness 1/4" 1/4"
Square Feet/Pallet 9,000 9,000

1 Specimens were aged and tested in accordance with FTC Rule (16 CFR, Part 460). The R-values shown for GreenGuard®-FP1450, GreenGuard®-XFP14, GreenGuard®-FP38, and GreenGuard®-XFP38 are system R-values calculated in accordance with the “ASHRAE Handbook of Fundamentals” using a ½” uniform, parallel dead air space. The R-values of these products installed without the benefit of a dead air space are 1.0 (GreenGuard®-FP1450 and GreenGuard®-XFP14) and 1.5 (GreenGuard®-XFP38).

2 These numerical flame spread and smoke ratings are not intended to reflect hazards presented by these materials under actual fire conditions (core data).

3 These dimensions apply to each fanfolded bundle.