Our Foil Scrim Kraft Faced Insulation (FSK Insulation) is a high-performance thermal insulation facing and vapor barrier engineered to optimize temperature regulation and moisture control across commercial and industrial building assemblies. Combining an 18-micron aluminum foil surface, a tri-directional fiberglass scrim mesh, and a high-strength kraft paper backing, this multi-layer material delivers maximum radiant heat reflection, high tensile strength, and low vapor permeability. It is the ideal choice for wrapping fiberglass ductwork, insulating exterior building walls, and sealing ceiling or basement cavities against moisture intrusion.
Engineered for mechanical insulation contractors, HVAC technicians, and building envelope specialists, Foil Scrim Kraft Faced Insulation provides critical protection against thermal loss and condensation buildup. The laminated construction functions as a continuous radiant heat shield and vapor retarder, preventing moist ambient air from entering porous fiberglass or mineral wool cores where condensation can lead to mold growth and reduced thermal resistance.
The outer 18-micron pure aluminum foil layer reflects up to 95% of radiant heat while presenting a clean, professional finish. Embedded directly beneath the foil, the 5mm x 5mm square fiberglass scrim reinforcement adds high tear and puncture resistance, preventing damage during handling, cutting, and jobsite installation. The kraft paper base layer acts as an effective secondary vapor barrier, ensuring structural stability and smooth adhesion to underlying thermal insulation materials.
|
Physical properties |
Test Method |
Value (English) |
Value (Metric) |
|
Basis weight |
Scale |
17 lbs / 1000 ft2 |
83 gsm |
|
Permeance (WVTR) |
ASTM E96, Procedure A |
0.02 perm |
1.15 ng/N.s |
|
Tensile Strength-MD |
ASTM D828 |
17 lbs / In |
75 N/25mm |
|
Tensile Strength-XD |
ASTM D828 |
17 lbs / In |
75N/25mm |
|
Burst Strength |
ASTM D774 |
50.8psi |
35 N/cm2 |
|
Low temperature Resistance |
ASTM D1790 4 hrs @ -40℉ (-40℃) |
Remains Flexible No Delamination |
Remains Flexible No Delamination |
|
High temperature Resistance |
ASTM D1790 4 hrs @ +240℉ (+116℃) |
Remains Flexible No Delamination |
Remains Flexible No Delamination |
|
Emissivity |
ASTM E408 |
-0.05 |
-0.05 |
|
Composition |
Description |
Value (English) |
Value (Metric) |
|
Foil |
Aluminum |
0.72 mil |
18 micron |
|
Reinforcing- MD |
Fiberglass |
1/5 inch spacing |
5mm spacing |
|
Reinforcing-XD |
Fiberglass |
1/5 inch spacing |
5mm spacing |
|
Heat-Activated Adhesive |
Polyethylene |
1 mil |
25 micron |
A: FSK stands for Foil, Scrim, and Kraft. It refers to the three-layer laminate construction made of an outer aluminum foil, a fiberglass reinforcing scrim mesh, and a kraft paper backing.
A: The fiberglass scrim provides high tensile strength and puncture resistance. This prevents the delicate aluminum foil from tearing during stretching, handling, and wrapping around sharp duct edges or mechanical corners.
A: Yes. The combination of pure aluminum foil and dense kraft paper creates an effective vapor retarder that prevents moisture vapor from penetrating into the insulation material, protecting against mold growth and thermal degradation.
A: FSK facing is typically wrapped over fiberglass or mineral wool blankets on ductwork and secured using mechanical fasteners or outward-clinching staples, then sealed along all seams using matching FSK aluminum foil tape for a continuous vapor barrier.
A: Yes. FSK facing is specifically designed to control moisture levels and reduce condensation issues, making it highly effective for basements, exterior walls, and HVAC systems in high-humidity climates.
