Comprehensive Guide to Mono Trusses: Design, Applications, and Installation


Mono trusses, also known as monopitch or shed trusses, are a popular structural component used in construction for their simplicity and versatility. These trusses feature a single sloping surface, making them ideal for a variety of applications, from residential homes to commercial and industrial buildings. In this comprehensive guide, we will explore the design principles, applications, benefits, and installation considerations associated with mono trusses.

Understanding Mono Trusses

1. Definition and Structure

A mono truss is a type of roof truss characterized by its single-sloping surface. Unlike traditional trusses that form a triangular shape, mono trusses have a simplified design with a single pitch. The structure typically consists of horizontal bottom chords, diagonal webs for support, and a sloping top chord. This straightforward design makes mono trusses easy to manufacture and install.

2. Types of Mono Trusses

Mono trusses come in various types, each serving specific purposes and accommodating different architectural styles. Some common types include:

a. Mono King Post Truss

This type features a vertical post, known as the king post, extending from the center of the bottom chord to the peak of the truss. The king post adds stability and visual interest to the structure.

b. Mono Howe Truss

In the mono Howe truss, the diagonal members slope towards the center, meeting at a central vertical post or king post. This design provides robust support for the roof structure.

c. Mono Pratt Truss

The mono Pratt truss features diagonals sloping outward from the center towards the bottom chord ends. This design offers simplicity and efficiency in load distribution.

3. Advantages of Mono Trusses

a. Simplicity in Design and Manufacturing

One of the primary advantages of mono trusses is their simple design, which facilitates easy manufacturing. The streamlined structure allows for cost-effective production and quicker installation, making them an attractive choice for various construction projects.

b. Versatility in Roof Design

Mono trusses are versatile and can be employed in a range of roof designs, including lean-tos, pent roofs, and skillion roofs. This adaptability makes them suitable for both residential and commercial buildings with diverse architectural requirements.

c. Efficient Use of Space

The single-sloping nature of mono trusses allows for efficient use of space within a building. This is particularly beneficial in structures where maximizing interior space is a priority.

Applications of Mono Trusses

1. Residential Construction

Mono trusses find widespread use in residential construction, especially in homes with contemporary or modern architectural styles. Their versatility allows for the creation of unique rooflines and the incorporation of large windows, adding to the overall aesthetic appeal of the home.

2. Commercial and Industrial Buildings

In commercial and industrial settings, mono trusses are utilized for their efficiency in spanning large distances. Warehouses, storage facilities, and industrial buildings often feature mono trusses due to their cost-effectiveness and ability to provide ample interior space.

3. Agricultural Structures

Agricultural buildings, such as barns and equipment sheds, frequently employ mono trusses. The simplicity of their design makes them a practical choice for these structures, providing reliable support for roofs covering extensive areas.

Design Considerations for Mono Trusses

1. Load-Bearing Capacity

The design of mono trusses must account for the anticipated load-bearing requirements. Factors such as snow loads, wind loads, and the weight of roofing materials should be considered to ensure the trusses can withstand the environmental conditions of the location.

2. Material Selection

The choice of materials for mono trusses is critical to their structural integrity and longevity. Common materials include wood, steel, and engineered wood products. The selection depends on factors such as budget, design preferences, and local building codes.

3. Span and Pitch

Determining the appropriate span and pitch for mono trusses depends on the specific requirements of the building. Longer spans may require additional support, and the pitch influences the aesthetic appeal and functionality of the roof.

Installation Process for Mono Trusses

1. Site Preparation

Before installation, the construction site must be prepared to accommodate the trusses. This includes ensuring a level foundation and adequate space for maneuvering during the installation process.

2. Truss Layout

Careful layout planning is essential to ensure accurate placement of mono trusses. This involves marking the positions of trusses on the building’s frame, considering the predetermined spacing and alignment.

3. Lifting and Placement

Mono trusses are typically lifted into position using cranes or other lifting equipment. Precision is crucial during this phase to avoid misalignment or damage to the trusses. Once lifted, the trusses are secured to the supporting structure.

4. Bracing and Fastening

Proper bracing and fastening are critical for the stability and longevity of the mono truss system. Diagonal bracing is often installed to enhance lateral support and prevent movement.

5. Roof Decking and Covering

Following the installation of mono trusses, the roof decking is applied to provide a stable surface. This is followed by the installation of roofing materials, such as shingles, metal panels, or other selected coverings.

Maintenance and Longevity of Mono Trusses

1. Regular Inspection

Routine inspections are essential to identify any signs of wear, damage, or structural issues. Inspecting the trusses, connections, and roofing materials can help prevent more significant problems and extend the life of the structure.

2. Addressing Repairs Promptly

If any issues are identified during inspections, it is crucial to address them promptly. Repairs may involve reinforcing connections, replacing damaged members, or addressing issues with the roofing material.

3. Protecting Against Environmental Factors

Mono trusses are exposed to various environmental factors, including sunlight, rain, and temperature fluctuations. Applying appropriate coatings or treatments can protect the trusses from decay, insect infestation, and other forms of deterioration.

4. Load-Bearing Capacity Checks

Regularly check the load-bearing capacity of mono trusses, especially in areas prone to heavy snowfall or strong winds. Understanding the load limitations ensures the continued safety and stability of the structure.

Cost Considerations and Budgeting

1. Material Costs

The choice of materials significantly influences the overall cost of mono trusses. While wood is a traditional and cost-effective option, steel and engineered wood products may offer enhanced durability but at a higher price point.

2. Installation Costs

Installation costs include labor, equipment, and any additional materials required for the truss installation process. Choosing an experienced and reputable contractor is essential for ensuring a smooth and efficient installation.

3. Long-Term Cost Savings

While mono trusses may offer upfront cost savings due to their simplicity, it’s essential to consider long-term cost savings. Energy efficiency, maintenance requirements, and the lifespan of the structure should all be factored into the overall cost analysis.


Mono trusses stand as a versatile and cost-effective solution for a wide range of construction projects. Their simplicity in design, ease of installation, and adaptability make them a popular choice for residential, commercial, and industrial applications. Understanding the design principles, applications, and installation considerations outlined in this guide will empower builders, architects, and homeowners to make informed decisions when incorporating mono trusses into their construction projects. Whether seeking an efficient roofing solution or a design element that adds architectural interest, mono trusses offer a compelling option in the world of structural engineering.