Looking for a truss system that balances strength and simplicity? The Warren Roof Truss Design might be exactly what your project needs. Known for its efficiency and clean triangular geometry, this design has stood the test of time in both industrial and residential builds.
In this guide, you will learn how a Warren truss works, what makes it special, its ideal applications, and even how to analyze and calculate it correctly. Whether you are building from scratch or exploring types of roof truss designs, this article will walk you through the essentials.
Table of Contents
- What is a Warren Truss Design?
- Key Components and Structure
- Span Capabilities and Ideal Angles
- Common Materials Used in Warren Roof Truss Designs
- Advantages And Disadvantages Of A Warren Truss
- Common Applications of Warren Trusses
- Types of Warren Truss Designs
- Warren Truss Design Example
- Warren Truss Analysis Tips
- Final Thoughts
- FAQs
What is a Warren Truss Design?
A Warren truss uses a series of equilateral or isosceles triangles formed by its web members. The design alternates diagonal elements to evenly distribute loads throughout the structure. This design is often seen in bridges but is also popular in roof truss applications due to its clean force flow and material efficiency.
Quick Note: The Warren truss was first patented in 1848 by James Warren and Willoughby Monzani. The design was first used for railway bridges, but it continues to be used in both bridges and buildings today.
Reminder: The term “Warren truss” applies to both bridge and roof structures, but the geometry principle remains the same.
Key Components and Structure
A Warren Roof Truss may look simple at first glance, but its strength lies in how each part works together. Understanding the role of each component helps explain why this design is so efficient and widely used.
- The top and bottom chords are the long horizontal members that define the overall shape of the truss. The top chord supports the roofing material, while the bottom chord handles the tension forces and helps keep the structure stable.
- Diagonal web members run between the top and bottom chords, forming a repeating triangle pattern. These diagonals distribute loads evenly throughout the truss, helping to manage both compression and tension across the structure.
- Nodes are the connection points where the diagonals and chords meet. These are critical spots that carry concentrated loads and transfer them efficiently through the rest of the frame.
Tip: The accuracy of these connections is vital. When nodes and diagonals are correctly aligned and joined, the truss remains rigid and performs reliably under various loading conditions.
Span Capabilities and Ideal Angles
One of the reasons the Warren Roof Truss Design is so popular is its ability to cover large open spaces with fewer materials.
In most projects, a standard Warren truss can span anywhere from 10 meters to over 30 meters. The exact span depends on several factors, including the material used, the structural loads it needs to support, and the overall design configuration.
A common question is: What is the best angle for a Warren truss? The answer usually falls between 45 and 60 degrees for the diagonal members.
This range offers the best balance between structural efficiency and material economy. Shallower angles may require more material, while steeper angles might not distribute loads as effectively over long spans.
Important: These measurements are not one-size-fits-all. A qualified structural engineer must be involved in designing the span and angle according to your project requirements for safety and compliance purposes. The best layout depends on local building codes as well as weather conditions and roofing system types.
Common Materials Used in Warren Roof Truss Designs
The selection of materials for Warren roof truss construction determines the overall performance of the structure. Each material comes with its own strengths and limitations, so the selection of materials depends on project size, environmental factors, and budget and load requirements.
Here is a breakdown of the three most commonly used materials in Warren truss construction:
| Material | Strengths | Limitations | Best Suited For |
| Steel | Strong, durable, allows long spans, resistant to pests | Heavier, more expensive, may require an anti-corrosion coat | Large industrial buildings, warehouses, and commercial structures. |
| Timber | Lightweight, affordable, easy to handle | Lower strength, not ideal for long spans or humid zones | Residential homes, garages, sheds, and small to medium-sized community buildings. |
| Aluminum | Corrosion-resistant, lightweight | Expensive, lower load capacity than steel | Coastal properties, temporary structures, or modern buildings where low weight is important. |
Tip: Material selection should consider both span needs and environmental conditions.
Advantages And Disadvantages Of A Warren Truss
Before choosing a Warren truss for your project, it helps to understand where it shines and where it may fall short. Here is a quick look at its key strengths and limitations.
Advantages:
- Distributes loads evenly across the structure
- Uses fewer vertical members than other trusses
- Ideal for long spans without internal supports
- Efficient in material use and visually simple
Disadvantages:
- Not suitable for heavy point loads in the center
- Joint connections can be complex and require precision.
Note: The Warren truss works best with evenly distributed loads. For point loads or uplift forces, consider adding verticals or extra bracing.
Common Applications of Warren Trusses
The Warren Roof Truss Design is a practical solution for buildings that need wide, open spaces without internal columns. Its ability to span long distances while using fewer materials makes it a top choice in many commercial and industrial projects.
You will often see Warren trusses used in:
- Aircraft hangars, where open interiors are needed for large equipment and aircraft movement
- Gymnasiums and sports arenas provide clear, column-free floors for games and spectator seating.
- Exhibition halls and convention centers, where flexible layout and wide-open event space are essential
- Greenhouses offer strong but light support systems that allow maximum light and airflow.
- School halls and auditoriums, where unobstructed space supports assemblies, performances, and community events
Reminder: Warren trusses are ideal when your design calls for strength, simplicity, and an open floor plan without sacrificing efficiency.
Types of Warren Truss Designs
Although the Warren truss is widely recognized for its repeating triangle shape, there are a few variations tailored to different structural needs. Each type is designed to handle loads in its own way, depending on how the forces are applied and the type of structure it supports.
| Type | Key Features | Best For |
| Standard Warren Truss | Uses only diagonal members forming a row of equilateral triangles | Ideal for structures with evenly spread loads |
| Warren Truss with Verticals | Includes vertical members at connection points to reduce deflection | Best for roof structures that carry point loads or a mix of loads |
| Modified Warren Truss | Features extra bracing or custom angles for greater load control | Suited for bridges, heavy dynamic loads, or custom designs |
Reminder: For most roof structures, the Warren truss with verticals is preferred. It gives you the structural support you need without complicating the design.
Warren Truss Design Example
Let’s take a simple example to see how a Warren roof truss works in a real-world setting.
Picture a steel-framed warehouse with a clear span of 20 meters. To support the roof efficiently, Warren trusses are installed at regular 6-meter intervals across the structure. Each truss is carefully engineered with diagonal members set at a 45-degree angle, which provides a strong balance between tension and compression forces.
For added strength and a clean finish, square hollow sections (often referred to as SHS) are used for both the top and bottom chords. These sections offer excellent load-bearing capacity and are easy to work with during fabrication and installation.
This setup creates an open, column-free interior that maximizes usable space while maintaining a strong and stable roof system.
Warren Truss Analysis Tips
Analyzing a Warren truss starts with understanding basic static principles. Before diving into internal forces, begin by calculating the support reactions. This gives you a solid foundation for working through the rest of the structure.
From there, use the method of joints or method of sections to find the force in each member. These techniques help you systematically solve the truss from one end to the other. In symmetrical designs, keep an eye out for zero-force members — they can simplify your calculations and reduce the number of active components.
A Warren Roof Truss Design Calculator can speed things up, especially in the early design phase. If you are working on more complex or larger-scale structures, tools like SkyCiv, SAP2000, and STAAD Pro offer advanced modeling and stress-testing capabilities.
Reminder: Even with software assistance, your final design should always be reviewed and approved by a licensed structural engineer.
Final Thoughts
The Warren Roof Truss Design provides builders with a dependable structural system that combines strength with efficiency. The repeated triangular pattern of this design provides excellent support while minimizing material requirements when properly engineered. This design works well for various construction projects.
Whether you are planning a warehouse, gymnasium, or light industrial facility, the Warren truss can provide the open space and strength your structure needs.
At Structural Wood Corporation, we specialize in helping clients create customized truss designs that match their goals and building requirements. From early planning to final checks, our team is ready to support you at every stage.
Need expert input on your truss layout? Reach out today for a consultation that fits your project.
FAQs
What is a Warren truss design?
It is a structure made of repeated triangles using diagonal web members, commonly used in both bridges and roofs.
What is the best angle for a Warren truss?
The ideal range is between 45 and 60 degrees to ensure a good balance between strength and material efficiency.
How far can a Warren truss span?
Warren roof trusses can span from 10 to over 30 meters depending on material strength and load conditions.
What are the advantages and disadvantages of a Warren truss?
Advantages include even load distribution and fewer verticals. Disadvantages include challenges with point loads and joint detailing.
Are Warren trusses easy to analyze?
Yes, using basic static methods, though complex designs should be verified with structural software or a licensed engineer.