Posts tagged: truss

Wooden roof trusses are engineered structural components designed to support a roof while efficiently transferring loads to the building below. For builders and contractors, trusses can also simplify the framing process because much of the design, cutting, and assembly takes place before the trusses ever arrive at the jobsite.

But what actually goes into making a wooden roof truss?

Long before lumber is cut or a truss is assembled, the process begins with the design of the building itself. Roof shape, span, loads, ceiling configuration, architectural requirements, and other project specifications all influence how a truss system is designed.

It Starts With Truss Design

A roof truss is made up of interconnected structural members that work together to distribute loads.

The top chords generally follow the slope of the roof, while the bottom chord spans the lower portion of the truss. Between them, a system of web members helps transfer loads throughout the structure.

These members connect at specific points, or nodes, using engineered metal connector plates.

The exact configuration depends on the requirements of the project. Different roof shapes, spans, loads, and architectural designs can require different truss configurations.

Modern truss design uses specialized computer software to model the truss and determine the dimensions and placement of its individual components before manufacturing begins.

How Truss Design Can Affect the Ceiling

The roof isn’t the only consideration when designing a truss system. The desired ceiling configuration can influence the truss design as well.

A conventional truss may accommodate a flat ceiling, while other configurations can be designed to accommodate different architectural requirements. Scissor trusses, for example, use sloped bottom chords and are commonly associated with vaulted or sloped ceilings.

This is why ceiling requirements should be considered early in the design process. The truss isn’t simply sitting above the finished space; the geometry of the truss can be an important part of creating that space.

For builders, architects, and designers, communicating these requirements before manufacturing helps ensure that the truss package corresponds with the plans and intended design of the building.

From Computer Design to Cut Lumber

Once the truss design has been completed and reviewed, the individual pieces of lumber must be cut to the specifications of that design.

Computer-controlled equipment allows manufacturers to make the precise cuts required for the chords and web members. Depending on the manufacturing equipment being used, this can include specialized saws capable of producing the angles and dimensions specified by the truss design.

The species and grade of lumber used can vary depending on the engineering and project requirements. Pine, spruce, and Douglas fir are among the species commonly used in wood truss manufacturing.

Accuracy at this stage matters. Each component needs to fit the engineered design before the individual pieces are assembled into a finished truss.

Assembling the Wooden Roof Truss

After the lumber has been cut, the individual components are positioned according to the truss design.

Metal connector plates are placed at the joints where the chords and web members meet. These plates contain teeth that embed into the lumber when pressure is applied, creating the connections between the individual members.

Manufacturing equipment helps position and press these components together according to the engineered design.

The result is a complete structural truss manufactured for a specific location and purpose within the building.

Quality Control Before Trusses Leave the Yard

Manufacturing doesn’t end when the final connector plate is pressed into place.

Completed trusses are checked to make sure they correspond with the required design and manufacturing specifications before they are prepared for delivery.

For a contractor, that means the trusses arriving at the project aren’t simply pieces of lumber that have been assembled into a roof shape. They are components that have gone through a process beginning with design and engineering and continuing through cutting, assembly, inspection, and delivery.

From the Truss Plant to the Jobsite

Once manufacturing is complete, trusses can be organized into packages and prepared for transportation to the project.

This is one of the major advantages of using manufactured trusses. Rather than constructing each roof component individually at the jobsite, builders receive structural components that have already been designed, cut, and assembled for the project.

Planning and coordination between the truss manufacturer and contractor are important here as well. The size of the trusses, project schedule, jobsite conditions, and delivery requirements can all affect how a truss package gets from the manufacturing facility to the building site.

More Than Pieces of Lumber

A finished wooden truss may look relatively simple, but there is a considerable amount of planning behind it.

The process brings together architectural requirements, structural design, specialized software, lumber, precision cutting, connector plates, manufacturing equipment, quality control, and delivery coordination.

And every project can present different requirements.

Stone Truss has been manufacturing roof and floor truss systems for Southern California builders for decades. From the initial plans through manufacturing and delivery, our team works with contractors to produce truss packages designed around the requirements of their projects.

Planning an upcoming project? Contact Stone Truss to discuss your roof or floor truss requirements.

The two most popular styles of roofing that utilize wooden trusses are hips and gables.  Both styles have advantages and disadvantages, and both can ultimately be a good choice for a home depending on the owner’s needs and preferences.  Either style can be strong and well-built using quality wood truss products, which will significantly reduce the cost and time spent on either style of roof.

Hip vs. Gable:  What’s the Difference? 

Hip and gable roofs are both quite common in today’s homes.  Gables, which feature two flat faces that form an “A” shape, may be slightly more common, especially on smaller homes, but hip roofs are often seen in areas where homes are custom built.  A hip roof has four sloping sides that meet at the top in a ridge.

From these basic definitions, there can be many variations.  For hip roofs, some of the varieties include:

• Pyramid hip. This is the simplest type of hip roof which creates a single peak at the top.  It is named for its pyramid shape and is often repeated in different sizes for a custom roofing look on a home.
• The mansard features two slopes on each side of the roof, with the bottom slope being steeper than the top.  A variation of the mansard, known as a combination roof, reverses this and flares the bottom slope wider than the top.  Both looks are popular in architectural styles that mimic certain historical periods.
• Hip and valley. A hip and valley roof is simply a series of hips that include low-lying areas known as valleys.  Care must be taken in constructing this type of roof to allow for proper water drainage so that rain and snow do not build up in low areas.

For gable roofs, varieties can include:

• Open or boxed gables. Most gables are either open at the end or closed in, with the roofline extending beyond the end of the gable.  These are known respectively as open or boxed gables and are common on ranch homes built in a straight, rectangular footprint.
• Cross gables. Another common method of utilizing gable roofing is to have gables make right angles to each other, forming a cross or even an L-shaped home.
• Gambrels and saltboxes. When gables are made with irregular shapes, the gambrel or saltbox is the result.  Gambrels are reminiscent of barn roofs, while saltboxes are popular on one-and-a-half story styles that slope down sharply in front but leave room for a second floor in the back.

Advantages and Disadvantages of Hips and Gables 

Both hip and gable roofs have advantages and disadvantages, based on their structure.

Advantages of hip roofs:

• Better performance in high winds. Because hips do not present a flat end surface to the wind, they are less likely to suffer from shear in high wind situations.
• Easier to build. Hip roofs are often easier to build than gable roofs and save time on construction jobs.  However, they often cost more than gables.
• May save on insurance. Some insurance companies give slightly lower rates for hip-roof houses because of their resistance to wind and stress.

Advantages of gable roofs include:

• Better snow performance. Gables are often used in cold-weather climates because they can handle snow load much more readily.
• Less expensive. Gables are usually cheaper to build than hip roofs, depending on size.
• More attic room. Gables offer more opportunity to utilize attic space, since headroom is more consistent throughout the roofline.

If you are considering a new roof or building project, let the professionals at Stone Truss help you decide on the right roofing trusses to make your job easier!  We can offer you experienced advice on choosing the right trusses for your job.  Give us a call today!

Many people have heard of wood trusses and know that they may save a great deal of time and money for builders on many different job types.  Whether the construction involves a small home, a commercial building, or even a large apartment complex, trusses are often used to cut the cost of materials and labor compared to conventional framing.  However, even though many people know that trusses save money, they may not understand the basics of what trusses are made of or how they work.  In fact, many people think that a truss building is quite complicated and that trusses are extremely difficult to design and build.

In reality, trusses are relatively simple structures that, nevertheless, are incredibly versatile and functional.  The basics of a truss roof allow for almost limitless variations, making roof trusses one of the most adaptable components on a construction job.

What Is A Wooden Roof Truss and How Is It Built?

A wooden roof truss is, at its simplest, are pieces of wood connected with metal plates and either nails or screws.  Some form of truss construction has actually been used for thousands of years, but the modern truss has been produced since about the 1960s.  By making trusses very uniform and easy to create, mass production was made possible. 

Wooden trusses that are connected with metal plates are by far the most common type used in residential applications.  The lumber used is typically 2 x 4 or 2 x 6 timber, often Doug Fir or Spruce Pine.   

The Parts of the Truss

A truss generally has three sides which make up its perimeter, although specialty trusses may have more.  The typical truss has a triangular shape made of members called “chords.”  Between these, a varying number of pieces called “webs” connect each of the chords together.  These are all held together with toothed metal plates that are pressed or screwed in place.  Once a truss is fabricated and put together, it is incredibly strong.  The metal plates provide security and anchoring, while the wood allows for a certain amount of flexibility, meaning that trusses can bend and flex to a degree in high winds or under stress, avoiding breakage.  Truss roofs often last for many years thanks to this durability.

Trusses are typically categorized two ways:  as parallel chord trusses, which are used in flooring or for flat roofing; and in the more common pitched chord trusses, which are used for sloped roofing.  With pitched chord trusses, variations in the angles of the members can create any roof pitch needed, allowing builders a wide range of creativity in roofing options. 

If you want to know more about truss roofing or flooring, the professionals at Stone Truss are happy to help!  Give us a call today to learn more about how we can help you save money and time on your next building project.