MAX 3.75-6 Panels Per Box

Product Overview

The MAX 3.75 interior/exterior insulation and framing panel. The Max 3.75 (R-Value 15.9) insulation panel is optimized for masonry or framed construction.  Order 6 panels or 3 panels.


SKU: FP-3.75-6 (6 panels 48 sq-ft.) 

Product Video

Engineered Features

R-15.9 Continuous Insulation

At 3¾ in thickness, the MAX 3.75’s closed-cell, injection-molded EPS foam body achieves R-15.9 insulation.

EPS is a non-toxic, inert insulation that maintains its R-value throughout the life of your building. Because it does not absorb moisture like open-cell types of bead board, it is rated highly for below-grade applications like basements. The EPS body has a fire-retardant material and serves as a Class III vapor barrier.

Strong Mold-Resistant Studs

Each panel is co-molded with three high-strength polypropylene studs that align every 16-in O.C. The anterior surfaces are fully embedded by a ½-in of insulation while the posterior surfaces feature ribbed dovetails for adhesive applications against interior concrete, stone, metal or brick walls.

They provide a straight surface that can support drywall attachment and exterior finishes as well as adornments like cabinets and TVs. They are not prone to moisture damage, and do not conduct heat along a wall system.

Self-Leveling Tongue-and-Groove Interlocks

Four tightly interlocking edges along each panel form a continuous, self-flashing seal. Unlike traditional flashing tapes, the interlock create a resilient seal that will not change shape, dry or crack over time. The interlocks eliminate the potential for mistaken thermal leaks and prevent water from reaching the face.  A notched alignment system ensures the panels and studs stay aligned during installation even when cut. Inset lines demarcate the location of wiring chases.

Moisture Control

Built into the back of the MAX panel is a network of shingle-style capillary channels. The channels are specifically-sized cavities that moderate wall pressure so that both interior and exterior wall assemblies can drain and be allowed to remain dry. The EPS foam features a permeability that ensures moisture is not trapped in walls and, with help from the channels, will “breathe” through to be handled by any standard HVAC system.

Electrical Raceways

Sealed electrical raceways runs vertically at 16 inches on center and horizontally at 24 inches on center.

This grid provides easy access to pull wiring to any location. Located at code-approved depth, the chases also provide the necessary separation from the drywall face to protect the wiring.

Double Thermal Disconnect

  • Uninterrupted continuous insulation (CI)
    • InSoFast goes beyond just “CI”. The fastener that attaches the panel is recessed a ½” reducing thermal shorts to near zero.
    • Fastening the cladding does not penetrate the water resistant barrier keeping your building secure and dry.
  • MAX 3.75 panel R-15.9 continuous insulation is the best choice for continuous-continuous insulation.
Physical Properties, Architectural Details

MAX 3.75 Insulated Flat Panel with Studs

FP-3.75 Panel Details dfx  – dwg – pdf
  FP-3.75 zip file
Architectural Submittal pdf
Panel Dimensions 24in × 48in × 3¾in
Sealed Horizontal Chase 24″ o.c.

 48in × 1in × ¾in

Sealed Vertical Chase 16″ o.c.

 24in × ¾in × ¾in

Drainage Channel 24in × ¼in × ¼in


8 sq-ft

R-Value ASTM C518



2×4 Wall/R-20 Batts

ASTM C578 Type II

     CAN/ULC S701 Type 2


injection-molded EPS 

ASTM C303 Foam Density

1.35 lbs

per cubic foot

ASTM E96 Water Vapor Permeability

 (Class III Vapor Retarder)


Maximum Service Temperature

(long term)

167°F = 75 Celsius (°C)

Co-Polymer Insulated Stud

Recessed ½in below Surface

Interlocking Edges

Service Raceways

Cutting Indication Lines

Designed Ready for Finishing Attachment


Exterior Rated Moisture Control


Section R703.1.1-approved 

Exterior Application

Interiors Application


Foundations Walls
Shipping Containers
Tiny Houses
Passive House
LEED/Green Build
NFPA Assemblies
Estimating Panels

Estimating and ordering is simple measure the square feet of floor, wall, or ceiling surface that the project requires to complete the job. Divide the total square footage (xx) by 48 sq-ft. this will determine the number of boxes required for your project, (round up to the whole box count). Don’t overestimate.

    • One (FP-3.75 Insulated Panel = (8 sq-ft)
    • One box of FP-3.75-6 (6 panels 48 sq-ft.
    • One box of FP-3.75-3 (3 panels 24 sq-ft.
Estimating Adhesive

Estimating Adhesive Quantity

Estimating adhesive has variables beyond our control, the condition of the wall, and how accurate the tradesmen is with a glue gun? The adhesive manufacturer’s technical sheet states, “A 3/8” (9.5 mm) bead extrudes approximately 38 ft. (12 m).

  • We recommend that you estimate approximately 10% waste or
  • 1 tubes of the adhesive = 50 Square feet of wall.

 To verify that enough adhesive is used, press the panel into place. Pull the panel back and check to see if the adhesive has spread out beyond the full width of the stud. It is normal for the panel to “float out” from the side of the wall when it is accommodating irregularities the adhesive will bridge gaps up to 3/8″. 


Rough estimate for  28 ounce tubes of adhesive required

Square Feet InSoFast Boxes LOCTITE® PL PREMIUM®3x
800′ 20 16
1200′ 30 24
2000′ 50 40
3600′ 90 72

Overview / Technical Data

Shipping, Purchasing & Returns

Please read all the current Shipping, Purchasing & Returns *

Freight Details / Dimensions Weight
Product Code

Number of Parts

Box Dimension

Cubic Feet Per Box

 Weight Per Box




MAX 3.75-6

6 Panels 48 SqFt





26 Lbs

MAX 3.75-3

3 Panels 24 SqFt





16 Lbs

Add R-Value with InSoFast PLUS

It’s easy to increase your R-Value beyond R-10 while maintaining the engineered benefits of the continuous InSoFast panels. Just start with a base of feature-rich InSoFast panels.