All panels are manufactured in IPB climate controlled factory following a precise series of steps using specially designed equipment. Structural adhesive is applied in exact amounts to the gluing surfaces before the assembled components enter our 3000 lb. hydraulic press for a specified time for curing.

Detailed guidelines ensuring quality control are adhered to during every step. In house monitoring and periodic outside audits confirm that all procedures are strictly followed.

Individual panels are numbered and tracked for accountability. Adhesive sample records are taken for each panel run and permanently kept for quality assurance.

Panel Insulation Weight
Thickness R-value per inch RSI per inch Lbs. per sq. ft.
4½ inch 18 2.60 3.21 lbs
6½ inch 27 3.64 3.47 lbs
8¼ inch 36 5.06 3.61 lbs
10¼ inch 44 6.18 3.78 lbs
12¼ inch 52 7.67 3.94 lbs
Standard Panel Size
Thickness Width Length
4½ inch 4’ 8’ 9’ 10’ 12’
6½ inch 4’ 8’ 9’ 10’ 12’
6½ inch 4’ 8’ 9’ 10’ CCMC* Approved
8¼ inch 4’ 8’ 9’ 10’ 12’
10¼ inch 4’ 8’ 9’ 10’ 12’
12¼ inch 4’ 8’ 9’ 10’ 12’


IPB holds CCMC Evaluation Number 13672-R for its insulated wall panels. Issuance of a CCMC number means that IPB wall panels are compliant with the National Building Code, do not require engineering for 6 ½” walls 10’ or less.

CCMC issues an evaluation number upon successful completion of comparative tests using known construction materials. The IPB wall panel comparative test was a 2 X 6 wood frame wall; tests showed that IPB panels are stronger than the 2 X 6 wood frame wall by almost double.

In building construction any wall taller than ten feet high must have review and approval by either an Architect or an Engineer.

Panel Performance

The expanded polystyrene (EPS) rigid foam insulation used in SIPs provides insulation, strength, and fire resistance. Low VOC, precise thickness structural OSB is used for the facers and water activated structural adhesive ensures bonding.

We’ve never experienced de-lamination of a panel.


The Expanded Polystyrene (EPS) core of a SIP provides 30% more insulation for every inch than fiberglass batt insulation. A SIP structure has ten times the air tightness of a conventionally constructed building, making the insulation that much more effective.  Long-term studies demonstrate that EPS rigid foam insulation is stable and does not shrink over time.


Evaluation reports done by the Canadian Construction Materials Centre (CCMC) indicate that IPB Structural Insulated Panels are more than twice as strong as a wood framed wall section they were compared to during testing of IPB’s SIPs.

SIPs derive their strength from the combination of the structural OSB, bonding to and the compressive strength of the EPS. Lumber splines used to connect the panels provide load bearing properties as required by good building practices and the building code.

OSB used in manufacturing IPB wall panels is structurally rated sheathing. When it is pressure laminated using structural adhesive to the expanded polystyrene core, it creates three directions of strength; axial, transverse and racking to the individual wall panel. When the panels are assembled into whole wall sections, the strength is carried in these planes to the whole assembly.

After a wall section is stood up, glued and nailed off, it is very stiff and noticeably more stable than a wood framed wall.


It’s no wonder that antidotal evidence from catastrophic events; hurricanes, tornadoes and earthquakes around the world show that SIP constructed buildings are still standing while entire neighboring districts built with conventional wood framing are flattened.


EPS is a type 1 closed cell rigid foam approved as an insulating material in the National Building Code. It has an R-value of 3.85 inch (RSI of .65 per 25mm), and doesn’t shrink over time (the scientific term is non-drifting). Non-drifting also means that it does not off gas VOCs. In insulating foams, drifting occurs when gases used to form the foam insulation leave it, as the gas leaves the foam shrinks.


The Life Cycle Analysis of EPS shows it to be the most impressive of all rigid foam insulations based on insulation performance per dollar per square foot. Comparison studies show that SIP built homes will use 50% of the energy a conventionally built home would use in the same time period.  SIP construction also contributes to less overall emissions; directly from the home and indirectly from associated manufacturing benefits of EPS.

Fire Resistance

Building Codes require fire retardants to be added to foam insulations but it is the completed wall assembly that truly makes it fire resistant.

In the event of a fire originating inside a building, flame must burn through the inside wall surface covered with gypsum board before it can reach the inner face of the panels OSB . Gypsum board is proven to provide 30 minutes of fire resistance to the wall assembly (as per the building code). After 30 minutes if flame reaches the OSB face it must burn through the OSB’s 7/16″ thickness before it reaches the SIPs EPS foam core. The EPS foam will not sustain fire or burn when its subjected to a concentrated flame it only burns when the entire skin of the OSB is destroyed because it needs air to burn.

Empirical evidence demonstrates that a home constructed with SIP walls and a truss roof if involved in a catastrophic fire will have its roof destroyed but the walls will still be standing.

For SIP roofs antidotal evidence shows that in catastrophic wildfire events homes constructed with SIP roofs survive while homes built with truss roofs are lost. Eye witnesses to these events have told this writer that burning embers are sucked through the building’ roof soffits into the attics of the truss roof. The fire in the home actually begins in the attic where it cannot be fought. SIP roofs don’t have attics so they don’t suffer the same fate.

Custom Size Panels

IPB manufactures its panels to a standard size of 4′ wide and lengths from 8′ to 12′. When bigger or smaller panels are required Standard panels are cut down or joined together. Purpose panels such as panels with a door or window opening, header or corner panels are configured at the factory to be ready for onsite assembly.  See CUTTING and BLOCKING


Just like building blocks!

It’s true, it’s that easy. Prefabricated panels are delivered to your site ready to assemble.

Panels have recessed edges (grove) that connection lumber is inserted into, which also stick out and inch and a half, ready for the next panel to connect to . Once fastened the whole assembly is incredibly strong. Generally speaking it takes about half the time to put up SIP walls than it does to stick frame and about the same amount of time to drop and entire insulated SIP roof as it does to install standard trusses (without any sheathing or insulation).

We’ve seen the walls of 40 x 60, 16 ft. high shop up in less than six hours, walls of a 3,800 sq. foot home up in 8 hours.

  1. Standing panels is easy, the recessed bottom edge is laid onto the bottom plate lumber, plumbed vertically and nailed off.
  2. The next panel is stood up and slid into the first panel.
  3.  Corner panels are screwed to each other.

Cutting and blocking refers to the process of customizing a standard size panel to be site ready to assemble with other wall panels in a whole wall section. Panels have to be cut and blocked with lumber for window and door openings, corners and to accept headers and beams.

Generally, for most buildings the majority of panels used in the whole wall assembly do not require any cutting, it will have more standard sized panels than cut and blocked panels.

Cutting involves changing the size and shape of the wall and roof panels and recessing the panel edges to accept lumber when required.

Blocking is the insertion of lumber when required. Lumber may be required as a spline (to connect two panels together) or for structural purposes.

Cutting and blocking is usually done to transform a standard panel into a purpose panel.

Purpose panels:

  • Corner panels
  • Window and door RO panels
  • Header panels

After cutting and blocking, these panels are site ready to be assembled with standard panels into a whole wall or roof section.

Cutting and blocking is usually done by IPB distributors or can be done by an experienced SIP construction crew.