FAQ
Category 1: House roof framing, installation of prefabricated roof structures, and truss systems.
How are prefabricated roof trusses better than traditional welded steel?
Prefabricated Roof Truss: High-precision, computer-manufactured steel structural trusses designed for quick installation, durability, and superior rust resistance. Made from high-tensile G550 galvanized steel, the system is assembled rapidly using screws without the need for welding, minimizing the risk of corrosion.
Black steel frame (welded on-site): Requires skilled craftsmanship to build and install, precise material estimation to avoid surplus or shortage, and welding points can lead to future rust. Crucially, it takes significantly more time to construct than a prefabricated roof truss system.
What Is a Steel Roof Truss?
โครงถัก หรือโครงทรัส เป็นโครงสร้างหลังคา ที่มีการออกแบบ – ถอดแบบจากโปรแกรมวิศวกรรมโดยเฉพาะ โดยการนำเหล็กมายึดต่อกันเป็นรูปสามเหลี่ยม โดยนำชิ้นส่วนวัสดุมาประกอบกันเพื่อช่วยกระจายแรง และรับน้ำหนักได้มหาศาล โดยใช้ปริมาณวัสดุน้อยลงแต่มีความมั่นคงสูง
How Much Does a Sigma Truss Steel Roof Truss Cost per Square Meter? Is It More Cost-Effective Than Traditional Welded Steel?
Using Sigma Truss prefabricated roof trusses or steel roof truss systems can reduce overall construction costs by up to 25–30% compared to conventional welded steel roof structures. The savings come from lower labor costs and significantly faster installation.
The price of a prefabricated roof truss per square meter starts at
เริ่มต้นเพียง 250 บาท/ตร.ม. (เฉพาะโครงหลังคา)
Final pricing depends on the complexity of the roof design, the total project area, and the transportation distance to the construction site.
Roof truss design, engineering, and factory prefabrication.
On-site assembly and installation at the customer's project site.
The key advantage of a Sigma Truss steel roof truss is its excellent strength-to-weight ratio. It is lightweight yet significantly stronger than conventional steel roof structures.
For pricing, project conditions, and special offers,
please visit our Sigma Truss Prefabricated Roof Truss Promotion page.
Or chat with our team on LINE for a free consultation.
Why Should You Choose Sigma Truss Prefabricated Roof Trusses?
Sigma Truss is a trusted brand of prefabricated roof truss systems, widely recognized for its quality and reliability,Every roof truss is designed using advanced computer-aided engineering software to ensure exceptional accuracy,Manufactured from high-tensile steel for superior strength and durability,Engineered to meet professional engineering standards and backed by a long-term anti-corrosion material warranty.
• Precision Engineering: Every roof truss is structurally analyzed using advanced engineering software to ensure optimal strength and safety.
• Long-Lasting Durability: High-quality steel with anti-corrosion protection is designed to withstand Thailand's tropical climate.
• Trusted Professionals: Our experienced team provides complete steel roof truss solutions for residential, commercial, and industrial projects.
Choose lasting strength and peace of mind with Sigma Truss prefabricated roof truss technology. Trusted by homeowners, contractors, and developers across Thailand, Sigma Truss delivers proven quality backed by engineering expertise and successful projects nationwide.
How Strong Are Sigma Truss Materials?
Sigma Truss uses G550 high-tensile steel with a tensile strength of 5,500 ksc, making it approximately twice as strong as conventional G240 mild steel. Each connection is secured with corrosion-resistant self-drilling screws capable of supporting loads of up to 300 kg per screw. This combination creates a steel roof truss system that is highly resistant to strong winds and built for long-lasting performance.
How Long Does It Take to Manufacture and Install Sigma Truss Roof Trusses?
Sigma Truss provides a complete steel roof truss solution, from design and manufacturing to on-site installation. Every roof truss is designed using advanced engineering software to ensure precision, structural strength, and safety. The design and manufacturing process typically takes 7–14 days, while installation is usually completed within just 3–5 days, depending on the project size and site conditions.
What Areas Does Sigma Truss Serve?
Sigma Truss supplies and installs prefabricated roof truss systems throughout Bangkok and the surrounding metropolitan areas, with free delivery available under promotional terms and conditions. We also provide steel roof truss design, manufacturing, and installation services for projects across Thailand. Our goal is to deliver high-quality roof truss solutions with excellent value for residential, commercial, and industrial projects nationwide.
What Information Do I Need to Prepare for a Quotation?
To provide an accurate quotation for your steel roof truss system, please prepare your house floor plan, roof plan, roof type (such as a gable or hip roof), roof pitch, building cross-sections, and the type of roofing material you plan to use.
What If I Don't Have a Roof Plan?
Don’t worry. Sigma Truss has a team of professionals who visit the site to inspect and take accurate on-site measurements Roof Truss using precise computer-aided engineering software. (Service fees may apply depending on the travel distance.)
What is the installation cost for metal sheet roofing materials?
For steel roof truss fabrication and installation with metal sheet roofing, the installation service cost is approximately 50–80 THB per square meter, depending on the complexity of the roof design and the project site distance.
Do you also provide roofing material installation services?
Sigma Truss specializes in steel truss systems as its core expertise. Currently, we also provide metal sheet roofing installation services. For other types of roofing materials, customers can consult our team on a project-by-project basis.
How long is the warranty for the steel structure and installation work?
We build confidence for customers who choose Sigma Truss (Sigma Truss roof system) by offering warranties that exceed standard market levels:
Steel roof truss installation warranty: 5 years
Material warranty (rust-free protection): 10 years
★ Most competitors in the roof truss market offer only 1–3 years of warranty.
Category 2: Metal Sheet Roofing / PU Foam Metal Sheet Panels / Pricing
How much does a metal sheet roof with steel roof truss installation cost?
Sigma Truss provides metal sheet roofing installation services together with steel roof truss systems. The cost is divided into two parts:
Prefabricated steel roof truss price:
250–400 THB/sq.m.
Metal sheet roofing installation labor cost:
80–120 THB/sq.m.
(depending on roof design complexity and site distance)
★ Metal sheet roofing and complete roofing system prices vary depending on material type, thickness, and brand. Please contact our team for a free full quotation.
What is PU foam insulated metal roofing and its benefits compared to standard metal sheets?
PU foam metal sheet (also known as PU sandwich panel) is a roofing sheet with a layer of polyurethane (PU foam) insulation sandwiched between two steel sheets. Its main advantages compared to standard metal sheet roofing are:
Better heat insulation, reducing indoor temperature by 5–10°C
Better noise reduction, as PU insulation absorbs rain impact sound
Improved indoor comfort, suitable for factories, warehouses, cold rooms, and residential buildings that require cooler conditions
Higher cost than standard metal sheets, but more cost-effective in the long run due to reduced air-conditioning energy consumption
★ Sigma Truss also provides consultation to help you choose the most suitable roofing material for your project. Feel free to contact our team.
How is CPAC roof different from metal sheet roofing, and which one should you choose?
CPAC roof (concrete roof tiles) and metal sheet roofing are suitable for different applications:
- CPAC roof / concrete tiles: Suitable for residential houses. It offers a beautiful appearance and high durability, but it is heavier and requires longer installation time. The roof structure must support a higher load.
Metal sheet roofing: Suitable for factories, warehouses, home extensions, and buildings that require fast installation. It is lightweight, cost-effective, and easy to maintain and repair. - Sigma Truss roof structures are compatible with both systems, depending on customer requirements and budget.
Category 3: C Purlins, Purlin Sizes, and Steel Purlin Pricing
What sizes are available for C purlins, and how much do they cost?
C purlins (C-shaped steel purlins) are an essential component of steel roof structures, used to support metal sheet roofing or roof tiles. Sigma Truss offers various C purlin sizes depending on application:
- C75 Purlin (75 mm)
Thickness: 0.65–0.80 mm — Suitable for residential roofs, carports, and awnings - C100 Purlin (100 mm)
Thickness: 0.80–1.00 mm — Suitable for residential roofs with medium span spacing - C150 Purlin (150 mm)
Thickness: 1.20–1.90 mm — Suitable for warehouses, factories, and long-span roof structures
C purlin pricing varies depending on size and thickness. Our engineering team provides free design and selects the appropriate purlin size for every project.
★ Truss spacing: up to 1.60 m for metal sheet roofing / up to 1.30 m for general roofing materials
Category 4: Home Extension, Roof Repair, and Roof Replacement
Does Sigma Truss provide home extension services, roof repair, and roof replacement?
Yes, Sigma Truss provides complete roofing services, including:
- Home extension: Design and installation of steel roof structures for building extensions, kitchens, balconies, and awnings
- Roof repair: Inspection of existing roof structures and proposal of repair solutions for both structural frames and roofing materials
- Roof replacement: Removal of old roofing and installation of new prefabricated steel roof trusses with metal sheets or PU foam metal roofing panels
All projects include free structural design and quotation provided by our engineering team before decision-making.
In which areas does Sigma Truss provide roof repair and roof replacement services?
Sigma Truss provides steel roof structure services, roof repair, roof replacement, and home extension services, covering the following areas:
- Bangkok and metropolitan areas: Free delivery available under promotional terms and conditions
- All provinces across Thailand: Service available nationwide
(Transportation fees may apply depending on distance)
How long is the warranty for the steel structure and installation work?
We build confidence for customers who choose Sigma Truss (Sigma Truss roof system) by offering warranties that exceed standard market levels:
- Steel roof truss installation warranty: 5 years
- Material warranty (rust-free protection): 10 years
★ Most competitors in the roof truss market offer only 1–3 years of warranty.
Can Sigma Truss roof structures support solar panels?
Yes, Sigma Truss roof structures can support solar panels.
However, standard steel truss systems are typically designed to carry roofing materials and wind loads as the primary forces. Solar panel systems generally weigh around 12–15 kg/sq.m., which is higher than standard roofing materials. Therefore, customers must inform the engineer during the roof design stage so the structure can be properly calculated and reinforced according to engineering standards.
What information is required to request a quotation for steel roof trusses and metal sheet roofing?
To allow Sigma Truss to provide an accurate quotation for steel roof trusses and metal sheet roofing, please prepare the following information:
- House plan or roof plan (if available)
- Roof type, such as gable, hip, or lean-to, including roof slope
- Approximate roof area (width x length)
- Preferred roofing material: metal sheet / PU foam metal sheet / roof tiles
- Type of work required: new roof / home extension / roof repair / roof replacement
★ If no drawings or plans are available, our team can visit the site for on-site inspection and measurement at no cost (travel fees may apply depending on distance)