Preflex Panels
#1 SIP Manufacture in the West Coast



Interior & Exterior Sheating


Preflex Panel

Structural Insulated Panels for Builders

Replace your stick-frame walls, floors, and roofs with structural insulated panels for residential and light commercial builds. Each panel is made up of a rigid foam insulation core laminated between two sheets of structural OSB, creating a flange and web structure similar to the strength of a steel I-beam and offering exceptionally thermal performance.They’re versatile, lightweight, energy-efficient, and sustainable.

Finish a structure in days

30% less construction time

20% less construction labor cost

50% less construction waste


Faster Construction

Prefabricated panels can be deployed quickly, built in as little as one (1) day.

Material & Labor Savings

Off-site fabrication results in accurate material and labor costs with no overages.

Sustainable & Energy Efficient

Low carbon construction and superior insulation results in up to 50% energy savings.

Avoid Labor Shortages

Remove the need for skilled carpentry.

Zero Waste Production

All material and scrap from fabrication are either recycled or reused for another project eliminating fabrication and job site waste.

Increase Property Value

Increased Energy Efficiency reduces operating costs while increasing property valuation.

Healthy Home

No VOCs, Healthy Interior Air Quality


Our designs are minimalistic, modern, and flexible enough to customize to your own taste.

SIP Panels



Preflex walls offer framing, insulation, and sheading with more structural integrity than studs. Our walls come ready to install with most of the work done off-site, such as electrical chases and box cutouts, and rough openings for doors and windows with headers and seals. Our walls make the interior finishes easier by allowing for drywall and cabinetry to be placed on any part of the wall thanks to the tensile strength of OSB.


Preflex roofs allow for great design creativity by removing the need for trusses, this allows you to obtain high vaulted ceilings while protecting you from the elements with the most energy-efficient roof system.


Preflex floors are easy to install, they remove the need for concrete and only require beams in one direction. By using our floors you ensure an air-tight build throughout the whole building envelope


• All SIP panels sent toCalifornia will come with an FBH insignia stamp of approval and will be reviewed by a certified QAA and DAA specialist.

• PREFLEX structural insulated panels are compliant with Los Angeles, California, and USA building and residential codes.

• Easily obtain Title 24 energy efficiencies.

• Materials are treated with borate for extended protection against termites, rot, fungus, and mold.

• No Urea formaldehyde or any other off gassin 0 VOCs

• ICC and NTA certification

Preflex R-values are true to their listed values, so that an R-16 panel will perform as an R-16 value once installed in the field.

Having an experienced team on your side when you’re new to SIP can help ensure that your projects don’t suffer any unexpected delays. We’ll ensure accuracy, timeliness, and optimal efficiency with convenient support throughout the process. As an industry leader, we’ve built our reputation on the satisfaction of customers like you by staying dedicated to quality products and service.

PREFLEX isn’t just a supplier. We’re a team of engineers, designers, manufacturing experts, and installation specialists who are ready to work with you to get the maximum benefit from your structural insulated panels. Your SIP panel build will offer superior energy efficiency, superior comfort and air quality, flexibility in design, structural strength, and the ability to finish the build much faster than before.

In addition to the exceptional advantages ofSIPs over stick framing, PREFLEX offers a 25-year guarantee against structural damage on your panels. The warranty guarantees that your product will meet specifications and be free from any defects, including any materials provided for installation purposes.
We offer the most complete SIP kit in the Industry.

Your Kits will include:
• Architectural drawings
• Structural design
• Manufacturing and delivery
• All Dimensional Lumber internal to the panel pre installed
• Splines Preinstalled
• PREFLEX service and support
• 25-year guarantee for structural damage

SIP Versus Stick Frame

Tight Envelope Continuous Insulation

Environmentally sustainable

1 days assembly with 4 installers: 700sqft

Engineering included

21 year product warranty

Fixed cost

Zero on site waste

Thermal bridging and air cavities

High carbon footprint

15 day framing with highly skilled carpinter: 700sqft

Engineering cost 6-8K

Floating Material cost estimates

Expensive change in order cost

Continues cleanup and trash hauling

Learn More

Frequently Asked Questions

What are SIPs?

Structural Insulated Panels (SIPs) are high-performance building panels used on floors, walls, and roofs for residential and light commercial buildings. The panels are made by sandwiching a core of rigid foam plastic insulation between two structural facings, such as the Oriented Strand Board (OSB). Other skin materials can be used for specific purposes. SIPs are manufactured under factory-controlled conditions and can be custom designed for each project. The result is a building system that is highly robust, energy efficient, and cost-effective. Building with SIPs will save you time, money, and labor.

How much faster can I build with SIPs?

SIP homes go up much faster than traditionally framed buildings. A properly trained SIP installation crew can cut framing time by 55% compared to conventional wood framing, according to a third-party study conducted by R.S. Means.

How much money can I save with SIPs?

Builders can save money through decreased construction and labor costs. A high-performance building envelope often allows HVAC equipment to be downsized and ductwork to be minimized. Builders can also significantly reduce jobsite waste disposal and temporary heat during construction. Homeowners that incorporate other energy-efficient features into a SIP home can see utility savings of 50% or more.

How sustainable are SIPs?

SIPs are one of the most environmentally responsible building systems available. It provides continuous insulation, is extremely airtight, allows for better control over indoor air quality, reduces construction waste, and helps save natural resources.

How strong are SIPs?

The structural characteristics of SIPs are similar to that of a steel I-beam. The OSB facers act as the fiange of the I-beam, while the rigid foam core provides the web. The design gives SIPs an advantage when handling in-plane compressive loads.

How do I properly size HVAC equipment?

A high-performance SIP building enclosure often allows smaller HVAC equipment to be specified. It’s important to work with a qualified HVAC professional that can accurately estimate the low levels of air infiltration in a SIP home or commercial building.

How important is ventilation?

SIP buildings are extremely airtight with air leakage rates well less than three air changes per hour at 50 Pascals of pressure (3.0 ACH50) and require mechanical ventilation.

Can SIPs be repaired or replaced if damaged?

Yes! A structural engineer needs to assess the damage to determine what is cosmetic and what is structural. There are SIPA members who act as consultants to determine damages.

Pre design Kits

Model 8

R 140ft²‍ | L 176ft²‍ | XL 210ft²

Model 12

R 192ft²‍ | L 288ft²‍ | XL 384ft²

Model 16

R 542ft²‍ | L 640ft²‍ | XL 768ft²

Model 20

R 640ft²‍ | L 800ft²‍ | XL 960ft²

Model 24

R 768ft²‍ | L 960ft²‍ | XL 1152ft²

Preflex Homes

What's Included

Architectural drawings


Preflex Service and Support

Structural design

All Dimensional Lumber internal to the panel pre installed

Splines Preinstalled

25-year guarantee for structural damage

Preflex Homes

Turn your Kit into an ADU

Request a Quote

How It Works

Our Process

Choose one of our pre-design models, or design your ADU using our 3D configurator.

Select from our catalog your interior and exterior finishes.

Preflex obtains Engineering stamp, Title 24 compliance and submits permitting.

Preflex manufactures SIP panels for your buildings.

Site preparations, this includes clearing the area of debris, foundation work and pulling MEP to site.

Finally, panels are received on-site and assembled in one-day.

Schedule a call with Our Team

Our Team of Experts will accompany you throughout your process.

Tax Incentives

HPP Cares 40k ADU Grants

Inflection Reduction bill tax incentive 45L for low carbon energy efficient stuctures

Retrofit Insulated Panels

Preflex Retrofit Insulated Panels (RIPs) Are Code Compliant with Building Residential codes at the Federal, and California State levels for use as load bearing, wall, roof, and floor elements.

The Perfect Solution

Sheathing provides an excellent substrate for all types of wall or roof cladding.

You can upgrade old structures to be energy efficient.

Integrated water-resistive barriers (RIPs).

Optional water-resistant barrier eliminating the need for house wrap (Wall RIPs Only).

It's a proven high-performance system for upgrading existing structures.

Continuous rigid air barrier with no thermal bridging.

All Installation accessories are available.

Customer Supports Includes: Design details and installation guidance.

21 Year Limited Warranty

Increase your Sales & Profits

With the RIPs System, you can increase your sales. We offer direct manufacturing prices so you can increase your profit margins. Plus, technical assistance when you need us.

Contact Us

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