FanFold by Plasti-Fab® is designed to provide a continuous insulating underlayment that will help to reduce air leakage that can create drafts that carry dust and dirt into the building envelope.

FanFold by Plasti-Fab® consists of a Type 1, expanded polystyrene (EPS) insulation core material (R-value of 3.75 per inch) with a thin film laminated to both sides. The branded film includes horizontal & vertical gridlines spaced at 51 mm (2’’) on centre to assist with installation. FanFold is manufactured by Plasti-Fab® so that each piece folds into a stack that can be handled easily. On the jobsite Fanfold opens into a 1.22 m x 3.66 m (4 ft x 24 ft) section that covers a large area quickly.

All of these features add up to make FanFold one of the most versatile products on the market today.

  • Available in 1.22 m x 3.66 m (4 ft x 24 ft)
  • Insulation Thickness: 3/8, 1/2 in.
  • Bundle includes: 2 pcs , 192 sq ft total coverage
  • Superior lay-flat design provides smooth surface for installation of new siding over old
  • Quick and easy application for labor saving efficiency
  • Lightweight, easy handling and installation

Material Properties of FanFold® Insulation

Material Property Test Method Units Property Values
Thermal Resistance
Minimum RSI per 25mm (R per inch)
ASTM
C518
m20C/W
(ft2•h•0F/BTU)
0.65
(3.75)
Compressive Resistance
Minimum @ 10% Deformation
ASTM
D1621
kPa
(psi)
70
(10)
Flexural Strength
Minimum
ASTM
C203
kPa
(psi)
170
(25)
Water Vapour Permeance2
Maximum
ASTM
E96
ng/(Pa.s.m2)
(Perms)
300
(5.0)
Water Absorption3
Maximum
ASTM
D2842
% By Volume 6.0
Oxygen Index
Minimum
D2863 volume % 24
Density
Minimum
C303 pcf 0.90
Thermal Resistance for Some Common Thicknesses
Millimeters RSI Inches R-Value
19 0.49 3/4" 2.81
25 0.65 1" 3.75
38 0.98 1 1/2" 5.63
50 1.30 2" 7.50
75 1.95 3" 11.25
Other Standard & Custom thicknesses available upon request.
Standard sizes range from; 2x4,2x8,4x4,4x8.

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