fbpx ThermaSteel FAQs | Thermasteel, Inc.

ThermaSteel FAQs

Frequently Asked Questions questions about ThermaSteel's composite, steel structural insulated panels.  If you can't find what you're looking for, please contact us by form or by phone. We'd be happy to take your call or answer by email!

What is the ThermaSteel Building System?

ThermaSteel is the leading manufacturer and innovator of composite, structural insulated panels. ThermaSteel panels are pre-Insulated light gauge steel framing, utilizing galvanized steel and EPS (both 100% Recyclable). ThermaSteel are the strongest, lightest SIPS (Structural Insulated Panels), or SSIPS (Steel Structural Insulated Panels) available in the building industry. They are “performance driven” structural components that have passed tests conducted by the Florida Hurricane Test Lab. ThermaSteel complies with the Department of Energy’s Model Energy Code, and are Energy Star Compliant. ThermaSteel is listed with the new International Code Council (ICC). ThermaSteel manufactures foundation, floor, wall, roof and ceiling components for commercial, industrial, and residential applications as well as infill or curtain walls for high-rise construction. ThermaSteel is the original manufacturer and developer of the system. Though many companies have attempted to duplicate the strength of ThermaSteel panels, the secret is in the steel to EPS bonding that creates a composite strength that cannot be duplicated by simply a steel framing structure with EPS for insulation.

The ThermaSteel Building System is a unique patented process utilizing the power of composite technology. A structural grade, opposing double steel framing members (G-90 galvanized, 24, 20, or 18 gauge) with rigid, fire retardant Modified Expanded Polystyrene Resin (EPS) bonded to the steel frames, forms a thermally broken, light weight (48-50 lb. for 5½” thick x 4’0” wide x 8’-0” high) composite building component that provides structural framing, insulation, sheathing, and a vapor barrier in one, fast, high-tech step. ThermaSteel components may be used for exterior and interior walls, partitions, floors, and roofs. Combinations of pre-insulated components are screwed together to form a unique high performance energy shell that is fast, lightweight and extremely strong. with superior thermal properties. Rough openings for doors and windows are formed during the manufacturing process.

ThermaSteel has completed over 70,000 projects around the world. Over 6 million square feet of structural panels were used in a commercial/industrial project in Mexico City. One thousand housing units for the US Government were constructed in Germany. The ThermaSteel system has been approved for use in all climatic regions and seismic Zone 9 in Russia. Senior Housing projects, hotels and condominiums are being constructed in many areas. A standard ThermaSteel panel with a modified exterior has passed the Hurricane Lab tests prescribed by Miami- Dade County, FL using protocol PA 201,202,203. There are projects in almost every state within the USA and many other countries around the world. The ThermaSteel System is being used in every facet of construction.

Return to top

What is Modified Expanded Polystyrene (EPS)?

The expandable Polystyrene resin used in ThermaSteel panels is modified by the supplier of the raw material to resist flame spread and is in full compliance with the ICC building codes and has received HUD approval. The use of EPS as rigid thermal insulation gives the ThermaSteel panel the following advantages:
• R-Values are consistent and stable due to the closed cellular structure, which contains stabilized air.
• Components are rigid and lightweight.
• Contains no CFCs or HCFCs. There is no off gassing.
• Contains no formaldehyde
• Resists fungus, decay and moisture gain
• Will not rot - highly resistant to mildew
• Environmentally safe.
• Lessens risks of cancer and of respiratory and skin irritations from certain other types of insulation.
• No food value for termites and other common wood eaters.

Return to top

What is the cost comparison of a ThermaSteel System vs. a traditional "stick built" structure?

Though it is not a budget building system, weighing all the factors such as speed of construction, strength to weight ratios, thermal efficiency, quality and consistency of materials along with reduced life cycle utility costs, ThermaSteel provides significant savings over conventional construction. ThermaSteel provides (1) structure, (2) vapor barrier, (3) sheathing, and (4) insulation, all at one time. Detailed cost comparisons can be furnished upon request.

Return to top

Why should I consider using the ThermaSteel Building System over conventional "stick built" structures?

It will save you big dollars. You will have a superior structure when you incorporate ThermaSteel components. We must consider the environment. The steel and EPS are fully recyclable. When you consider the waste on the typical job site, you can see the value of using ThermaSteel as costs are skyrocketing for landfill dump fees. The following are excellent reasons for using ThermaSteel Building Systems: Recently a five man crew, who had never seen ThermaSteel, installed 234 LF of 9’ wall in less than 7 hours. Another crew installed 1,250 LF of 18’-21’ high ThermaSteel walls in five days.

STRENGTH/INTEGRITY - Years in the field, not hours in the lab, give ThermaSteel Building Systems the advantage. Extensive structural testing has been performed by independent laboratories under ASTM E 72, C-518-76, E 96-80, E 119, E 90, E 413 to evaluate the structural integrity of the panels and to obtain building code compliance. ThermaSteel regularly performs the following tests on all sizes of the panels: Axial Compressive Load Tests, Racking Shear Load Test and Transverse Load Tests.

Hurricane Test: In August of 1998, a standard 5 ½” x 4’ x 8’ ThermaSteel wall panel assembly, reinforced on the exterior side with 24 gauge, G-90 galvanized metal studs closely spaced, was subjected to a series of test protocols required by Miami-Dade County, Florida, at the Hurricane Test Laboratory, Inc. in Riviera Beach, Florida. Three different specimens of ThermaSteel wall assemblies passed with flying colors.

THERMAL ENERGY PERFORMANCE: ThermaSteel wall panels are ENERGY STAR™ compliant. The ThermaSteel panel provides not only structural integrity, but excellent insulation properties as well. The EPS component of the panel is solid (except where wire chases are incorporated) and does not provide voids or allow air movement through the walls. The unique design and utilization of the steel structural members within the panel provides for a thermal break across the panel. In "stick-built" walls, each stud is a thermal conductor from one wall surface to the other. Quoted R-Values are only for the properly installed insulation between the wood studs. (Look at any thermal photo). Due to the low permeability properties of EPS (water resistance or ability of panel to breathe), ever-present moisture does not affect the R-Values or thermal performance. The unique design of the panel and the use of EPS as a component provide little or no R-Value drift or loss and results in a stable thermal performance for the life of the structure. Conventional types of batt and blown-in insulation may lose up to 50% of effective R-Value due to compression, dust and moisture retention. Even Urethane foam loses its R-Value over time. The R-Value of EPS remains the same in year 20 as on day 1.

The thermal insulating properties of expanded polystyrene are well known. In addition, ThermaSteel panels are designed with thermal breaks throughout. The steel studs are designed so as not to create a thermal bridge from inside to outside of the panel. Even the shiplap joints preserve the integrity of this thermal break. As determined by the Thermal Resistance Test (ASTM C 518-76 Aged R-Value):

US Metric @ 40F @ 75F Water Vapor Transmission
2¾” (70 mm) R-13 ; U or (k)=0.07 R-12 ; U or (k)=0.08
3½” (89 mm) R-16 ; U or (k)=0.06 R-15 ; U or (k)=0.066 .6 Perms
4” (102 mm) R-18 ; U or (k)=0.05 R-17 ; U or (k)=0.058
5½” (140 mm) R-24 ; U or (k)=0.04 R-23 ; U or (k)=0.04 .5 Perms
7½” (190 mm) R-34 ; U or (k)=0.03 R-32 ; U or (k)=0.03

Due to the following factors: Reduction of air infiltration, elimination of thermal bridges, effect of the interior and exterior cladding, effect of ship lap joints, the effective R & U-Values may be 34% over theoretical. E.g. A 3½” wall panel with no penetrating metal with exterior and interior finish is effective R-22; 5½” wall panel with no penetrating 2 x 6’s with exterior and interior finish is effective R-33 (k-value .030). 7½” is effective R-45.6 (k-value .023).

The R-Value only tells half the story for various materials used in wall assemblies and is not a measure of the thermal efficiency of a house. (Wood studs have an R-Value of approximately R-1 per inch and steel studs actually act as a heat sink). Rather, it is a measure of the resistance to heat loss by conduction, convection, and radiation of various materials. Heat loss occurs in other ways -- through cracks, poorly fitted windows and doors, and other forms of air infiltration. A conventionally framed house using batt insulation may experience considerable air infiltration. The ThermaSteel panel, due to its design and use of material, is extremely effective in limiting these forms of heat loss. A ThermaSteel home tested with the standard blower door pressure of 50 PASCAL’s was determined to have 35% lower air infiltration than a comparable wood frame house. Owners of ThermaSteel buildings have verified significant savings in utility bills when proper installation procedures are followed and the panels are utilized to their fullest extent. Example: A 180,000 SF senior living facility in Florida is saving thousands of dollars each month. Energy costs have been verified at $0.025 per SF of living area. A 28,000 SF single family residence is recording energy costs of $0.018 per SF of living area.

In a study conducted by energy scientists at the Oak Ridge National Laboratory* the stated R-Value of virtually every product on the market evaluated in the “real world” of thermal breaks such as, corners, windows, doors and stud walls was drastically reduced - EXCEPT Structural Insulated Panels. For example: A 2” x 6” stud wall 24” on center with R-19 fiberglass batts tested out with an R-Value of 13.7. A Structural Insulated Panel wall tested at R-21.7. That means that the Structural Insulated Panels out-performed a 2” x 6” stud wall by 58%. *ASHRAE Journal March 1996, Christian and Kosny

SOUND PERFORMANCE: Panels have been tested (ASTM E90, E413) as a wall system with gypsum wall board: 3½” panel STC 37, party wall STC 51, double 3½” panels with 2” air space STC 57. Other materials may be used on panels for other STC ratings.

PRECISION-QUALITY - ThermaSteel panels are manufactured in a controlled factory process. Each panel is inspected, measured and labeled. This assures In-Plant Quality Control along with third party inspection services (RADCO) and (OMEGA POINT LABS), in order to be in compliance with ICC Evaluation services and building codes.

CONSTRUCTION ADVANTAGES - Properly designed structures utilizing ThermaSteel panels speed up construction with resulting savings in labor costs and construction loan interest. There is also reduced site material waste, better site litter control, and reduced security requirements. Remember when a ThermaSteel wall is erected it is a structural load bearing rigid composite panel that provides structural framing, insulation, sheathing, and a vapor barrier in one high-tech step. Other advantages include:
1. Light Weight. Easy to handle.
2. Fast Assembly. Compare 64 sq.ft. of exterior load bearing wall assembled using self-tapping screws vs. 12 pcs. of wood, 6 batts of insulation, vapor barriers, corner bracing, 2 sheets of exterior sheathing, approx. 100 fasteners to produce 64 sq. ft. of wood load bearing wall . ThermaSteel panels eliminate an insulation day on the building schedule.
3. Dimensionally Stable. Walls are straight and true and will not shrink, twist or move the way wood does. Eliminates call-backs for nail pops and door adjustments.
4. Damage resistant. Because the EPS material between the studs is solid it makes it difficult to break the gypsum board. Conventional interior sheathing is easily damaged causing air infiltration problems and repair callbacks.
5. Quality. Finished walls are straight and flat. Appearance of exterior siding and interior drywall is significantly improved. Installing chair rail is actually a pleasure. Drywall installers prefer ThermaSteel because they have flat walls with a 3” target instead of a 1½” stud.

Return to top

How is electrical wiring and plumbing installed in the ThermaSteel Panel?

Pre-molded electrical chases can be provided in the EPS core of each panel as required. Electricians and plumbers familiar with commercial metal stud construction have no problem with the ThermaSteel System. A hot knife can be used to form custom raceways of various configurations for wiring and plumbing.

Return to top

Does the ThermaSteel panel require special or different materials for finishing the structure?

No. In fact most finishes require less work than old-fashioned "stick built" construction. The dimensional modules are compatible with standard 2x building materials. The 16" and 24" on-center metal stud members allow virtually all standard exterior and interior finishing materials to be attached and utilized with the panels. Cement based plasters can be applied following manufacturers' recommendations.

Return to top

What about changes and field modifications?

Using the right tools and techniques along with common sense and good construction practices modifications can be accomplished with ease. An assembly manual on CD or in printed form can be used as a reference and is available upon request. Technical assistance via phone or e-mail is available.

Return to top

Has the ThermaSteel System been tested and listed with the building codes?

Yes. Independent certified laboratories have performed extensive testing. Ongoing quality reviews and testing is conducted by a third party independent inspection service (RADCO) and (OMEGA POINT LABS). The ThermaSteel panel (also known as RADVA panel and Thermastructure/Wallframe panel) is currently listed with the new ICC-Evaluation Service. All current ICC-ES evaluation reports are "legacy reports," originally issued by one of the legacy evaluation services that came together on February 1, 2003, to form ICC-ES. Legacy evaluation reports may be accessed at the present time through the web sites of the legacy evaluation services that are still being maintained. Below is the list of evaluation reports originally issued by:
ICC-ES (International Code Council Evaluation Services)
ICBO - (International Conference of Building Officials) under the Uniform Building Code - ICBO # PFC 4216
BOCA- (Building Offices and Code Administration) under the National Building Code - Research Report #9140
SBCCI – (Southern Building Code Congress International, Inc.) – SBCCI # 2143

ThermaSteel also maintains listings with the following:
HUD - (Department of Housing and Urban Development) Bulletin No. 1072
UL - (Underwriters Laboratories) under Report #NC554
HURRICANE TEST LAB INC, Broward County, FL- Passed

Return to top

Have ThermaSteel Panels been fire tested as assemblies?

Yes. The panels have been systems tested with thermal barriers for surface burning characteristics; smoke development, room fire tests, and hourly fire test ratings, as per building code requirements. Panels have been tested as a wall system with gypsum wallboard thermal barriers for 15 minute, 1-hour, and 2-hour fire ratings. Most codes require a 15-minute minimum interior thermal barrier. Paper auto-ignites @ 451º F. Wood, depending on its species, auto-ignites @ approx. 500º F. EPS auto ignites @ approx. 904º F. Fire tests have proven that EPS gives off fewer toxins than conventional wood framing. UBC Std. 17-5, ASTM E 119. ThermaSteel panels have been tested as a wall system with gypsum wallboard thermal barriers for 15 min., 1-hour, and 2-hour ratings. Most codes require a 15-minute interior thermal barrier.
3½” , 1.5 PCF 5½”, 1.0 PCF
UL Flame Spread Rating 5-10 5-20
UL Smoke Developed Rating 65-300 125-175

Return to top

How do ThermaSteel panels stand up to termites, ants and wood boring insects?

The bottom line is insects just don’t feed on steel. The EPS portion of the panel is of a modified type, which offers no food value for insects. Certain species of termites will find ways to pass through minute cracks in concrete to get to their favorite food - wood. Likewise they have been known to bore their way through EPS to get to wood and ants have been known to nest in certain types of EPS. The problem has been corrected by soil treatment, by creating barriers between the panels and the slab, and by treatment of the panels. TAMBOR™ is an approved insecticide that can be applied into the bottom track to provide a barrier.

Return to top

Has the ThermaSteel system been patented?

Yes. There are various patents in USA in addition, several foreign patents apply and/or are pending.

Return to top

Have local building officials approved the use of ThermaSteel panels?

Yes! However, some regions have additional requirements for high wind load, heavy snow loads, high seismic activity, or any combination of these. ThermaSteel panels can be engineered to meet these additional requirements.

Return to top

Will I need special engineering?

Certain building designs and regions require a stamp or letter of recommendation from a licensed structural engineer. ThermaSteel, for an additional fee, can provide engineering on a case-by-case basis. Special designs and circumstances may require extra reinforcement. If special or specific engineering is required we can assist an engineer of your choice or recommend one who may be in your area.

Return to top

Who can I get to build for me?

If there were no experienced ThermaSteel builders in your area a competent builder/contractor would be able to complete the project. On site technical assistance can be provided. Commercial contractors, metal building erectors and drywall contractors are not afraid to work with steel and screws. Thousands of satisfied customers have built their own homes with a little help from friends and some technical support from ThermaSteel (see Question 17).

Return to top

16. How can I get an estimate done on my project?

Since project applications and structural load requirements often dictate the size and type of panels needed, our standard policy is to provide estimates from dimensioned architectural drawings that include floor plan, elevations and roof plan with rough opening sizes. We then adapt the plans to our system. Usually estimates are completed within a week of receipt of your drawings. The more detail we receive the more accurate the estimate, however, the estimate is based on drawings submitted for a material take-off. Prior to production we will submit a firm quotation for your approval.

Return to top

Once I decide to use the ThermaSteel, how do I place my order and arrange for delivery of my project?

Once you make the decision to use ThermaSteel on your project, your distributor will send a deposit and purchase order to ThermaSteel Corporation. At that time your architectural plans will be used to produce a set of shop drawings, which adapt our components to your plans. Due to the custom nature of each individual structure, a deposit of 10% of the estimated price is required before we begin shop drawings. Given the scope of the project and sufficient architectural details, a complete set of ThermaSteel shop drawings will be sent to you for final approval. At this stage, changes and additions can be made before the project goes into production. If your drawings require structural engineering, additional time will be required to complete the drawings and an extra charge will apply. Upon receipt of your signed approval of the shop drawings and an additional 50% deposit, the panels will go into production. Your project will be processed in the order in which it was received. Turn-around time is a function of demand and complexity of the project and can range from four to six weeks from the date of final approval. The panels will be delivered directly to your job site within this time period. Panels are typically shipped by common carrier or specialty carrier, which we arrange through a broker. Shipping charges are calculated from Radford, VA. You may also choose to arrange your own shipping. The balance due on your project must be paid before the panels are shipped.

Return to top

Does ThermaSteel provide technical support once my panels are delivered?

Yes. A representative of ThermaSteel will be available at our offices to meet with you and/or your contractor to review technical details and plans if needed. Your area ThermaSteel representative can provide local technical support. Additional support personnel can be assigned on a per diem basis. Call for a quote. A detailed set of shop drawings and an assembly manual will also be provided for ease in assembly.

Return to top