IKO IKOTherm Grade-II (20 psi) Polyiso Roof Insulation Board, 2 in. x 4 ft. x 4 ft. - image 1

IKO IKOTherm Grade-II (20 psi) Polyiso Roof Insulation Board, 2 in. x 4 ft. x 4 ft.

Regular price $19.27

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IKO IKOTherm Grade-II (20 psi) Polyiso Roof Insulation Board, 2 in. x 4 ft. x 4 ft.


This IKO IKOTherm Grade-II polyisocyanurate roof insulation board measures 2 in. thick, 4 ft. x 4 ft., with a 20 psi Grade-II compressive rating. Its kraft paper facer reinforced with glass fiber strands delivers high strength and excellent absorption for hot mop, adhesive, or mechanical attachment. Sold per piece; allow 16 boards per roofing square.


Key Features:

  • Broad system use: Designed to be part of modified bitumen, built-up, or single-ply roof systems.
  • High R-value per inch: Rigid polyiso foam with high thermal properties helps reduce heating and cooling costs.
  • Grade-II 20 psi: Grade-II compressive strength rated at 20 psi for low-slope roof assemblies.
  • Adhesion-ready facer: Kraft paper reinforced with fiberglass strands offers excellent absorption for hot mopping and adhesive attachment.
  • Mechanical fastening: Also performs well when installed with mechanical fasteners.
  • Easy handling: At under 7 lb per board, it is lightweight and easy to carry and cut on the roof.
  • Code-listed: Meets ASTM C1289 and CAN/ULC S-704, with FM Approval and UL Classification.

Specifications Table:

Specification Details
Brand IKO
Manufacturer model 4183013
Sell unit 1 board, 2 in. x 4 ft. x 4 ft.
Product line IKOTherm polyisocyanurate roof insulation
Profile / style Flat board, kraft/fiberglass-reinforced facers
Color Tan
Dimensions 4 ft x 4 ft x 2 in. thick
Coverage per unit 16 sq ft per board
Material Polyisocyanurate foam, kraft paper facer reinforced with glass fiber strands
Compressive strength 20 psi (Grade-II)
Applicable standards ASTM C1289; CAN/ULC S-704; FM Approved; UL Classified
Weight 6.752 lb per board
Algae resistance No
Intended use Modified bitumen, built-up, or single-ply low-slope roof insulation

Coverage & How Much You Need:

One 4 ft x 4 ft board covers 16 sq ft of roof deck. For one roofing square (100 sq ft), allow 16 boards (256 sq ft) to cover field cuts and staggered joints.

Fit and Compatibility:

Made for modified bitumen, built-up and single-ply low-slope roof systems; install per IKO and membrane manufacturer specifications. Other thicknesses, tapered variants, and attachment materials are sold separately.


Frequently Asked Questions (FAQ):

Q: How many boards do I need for 100 sq ft?
A: Each board covers 16 sq ft, so 16 boards give 256 sq ft, covering one square with joint stagger and cutting waste.


Q: What attachment methods work?
A: The fiberglass-reinforced kraft facer is designed for excellent absorption with hot mopping and adhesive attachment, and the board also performs well with mechanical fasteners.


Q: What is the compressive rating?
A: Grade-II polyiso is rated at 20 psi compressive strength per the ASTM C1289 classification.


Q: Which roof systems can it be used in?
A: IKOTherm is designed to be part of modified bitumen, built-up, or single-ply roof systems.


Q: What size is this board?
A: This item is 2 in. thick, 4 ft x 4 ft; IKOTherm is also offered in other sizes and thicknesses, sold separately.


Expert Verdict — Reviewed by the SuperArbor Pro Desk

A 2 in. Grade-II board is a versatile workhorse for base layers, upper layers in staggered two-layer assemblies, and re-cover work. Keep joints tight and staggered between layers, and verify fastener density against the project's wind-uplift design. Use the LTTR/aged R-value on the board label for code submittals.

Wear gloves and eye protection when cutting polyiso boards, and keep them clear of hot work and open flame during application.


Order the IKO IKOTherm 2 in. polyiso roof insulation board for your next low-slope roofing job.

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