Ridge Board Vs. Ridge Beam: What’s the Difference?

Choosing between a ridge board and a ridge beam is crucial for your roof’s stability and longevity. Ridge boards are non-structural and work well for standard sloped roofs, while ridge beams provide critical support for low-pitch or vaulted ceilings.

Most homes with a roof pitch between 3/12 and 12/12 use a ridge board because the rafters naturally support the load. However, if your home has a shallower pitch (below 3/12) or an open-concept design, a ridge beam is required to prevent sagging or structural failure.

In this article, we’ll break down the differences between ridge boards and ridge beams, including when to use each, installation requirements, and key cost factors so you can make the best choice for your roof.

Understanding Roof Ridges

The ridge is the highest point of your roof, where the two sloping sides meet. Think of it as the roof’s peak, running along the top of your home.

To support this ridge, builders use either a ridge board or a ridge beam, depending on the roof’s design.

• Ridge boards are non-structural and mainly help align rafters during installation.
• Ridge beams provide critical structural support and are required by building codes for certain roof types.

The right choice depends on your roof’s slope and design.

What Is a Ridge Board?

A ridge board is a non-structural piece of wood that runs along the peak of a roof, acting as a guide to help rafters stay in place during construction. It doesn’t carry weight but makes the roof-building process easier and more precise.

Why Ridge Boards Matter

A ridge board’s main job is to keep rafters properly aligned. Without it, builders would have to balance and secure rafters one by one, increasing the chance of errors. A well-installed ridge board ensures the roof stays even, stable, and properly supported by the walls over time.

What Are Ridge Boards Made of?

Most ridge boards are made of lumber, usually 1×8 for smaller structures and 2×8 or larger for bigger roofs. Some are made from treated wood to resist moisture and pests, which helps extend the roof’s lifespan.

When Should You Use a Ridge Board?

Ridge boards work best for roofs with a slope between 3/12 and 12/12. In these cases, the rafters naturally transfer weight to the walls, so extra support isn’t needed. That’s why most residential homes use ridge boards instead of ridge beams.

How To Install a Ridge Board

Since ridge boards aren’t load-bearing, they don’t require extra support. However, proper installation is still important to prevent future problems:

• Use a board that’s at least 1 inch thick.
• The board’s depth should match or exceed the cut ends of the rafters.
• Rafters must be securely attached to the ridge board for stability.

What Is a Ridge Beam?

Unlike a ridge board, a ridge beam is a structural support that carries the weight of the roof. It’s required by building codes for roofs with a slope less than 3/12 because these roofs don’t have steep enough angles for rafters to naturally support the load.

Why Ridge Beams Matter

A ridge beam acts as the backbone of the roof, transferring weight to strong supports like walls, posts, or masonry structures. Without it, roofs with low slopes or open designs could sag or collapse under heavy snow, wind, or long-term wear and tear. Ridge beams are common in A-frame, gable, and vaulted ceiling designs, where rafters need extra support.

What Are Ridge Beams Made Of?

The material and size of a ridge beam depend on the roof’s weight and span. Common materials include:

• Lumber – Typically 2×10 or larger, depending on the structural needs.
• Engineered Wood – Stronger and more resistant to warping or moisture damage.
• Steel – Used in larger or more complex roofs for maximum strength.

When Do You Need a Ridge Beam?

You’ll need a ridge beam if your roof has:

• A slope less than 3/12
• Vaulted ceilings or exposed beams
• An open-concept design that maximizes attic space

How Ridge Beams Are Supported

Since ridge beams carry weight, they must be properly supported. This is usually done with load-bearing walls, steel posts, or masonry structures.

A structural engineer should verify the beam’s design and installation to meet local building codes.

Can a Ridge Beam Be Spliced?

Yes, but it must be done carefully. If your roof is longer than a single beam can span, splices must be placed between rafters, not at the rafter connections. Attaching a rafter directly to a splice creates a weak spot that could compromise the roof’s strength.

How To Choose Between a Ridge Beam and a Ridge Board

The right ridge component is key to your roof’s strength, stability, and lifespan. Ridge boards are simple and cost-effective for most standard homes, while ridge beams provide essential support for low-slope or open-concept designs.

Some key factors to consider include:

✔ Roof Slope – If your roof is steeper than 3/12, a ridge board is enough. If it’s shallower than 3/12, you need a ridge beam for structural support.

✔ Load-Bearing Needs – Ridge boards don’t carry weight, while ridge beams support the roof’s load and must be properly reinforced.

✔ Home Design – If your home has vaulted ceilings, exposed beams, or a modern open-concept layout, a ridge beam is required. Standard homes with traditional attic spaces can rely on a ridge board.

✔ Attic Space – A ridge beam allows for more open attic space, while a ridge board is fine if you don’t need extra headroom.

Common Roof Types and Their Ridge Components

Different roof styles require different ridge supports. Here’s how to determine whether your roof needs a ridge board or a ridge beam.

Gable Roof

✔ Two sloping sides meeting at a peak
✔ Support needed: Ridge board for steep slopes, ridge beam for lower slopes

Gable roofs are one of the most common styles. If the slope is steep enough, a ridge board is sufficient. However, if the pitch is low, a ridge beam is needed for extra support.

Hip Roof

✔ Four sloping sides that meet at a ridge
✔ Support needed: Ridge board

Hip roofs naturally distribute weight across all sides, making a ridge board the best choice. Their steeper pitch also helps with water drainage and wind resistance.

Gambrel Roof

✔ Two-sided roof with two slopes per side (barn-style)
✔ Support needed: Ridge beam

Gambrel roofs often require a ridge beam because of their larger spans and heavier loads, especially in farmhouses and barns.

Mansard Roof

✔ Similar to a gambrel but with four sides
✔ Support needed: Ridge board or ridge beam, depending on height and slope

If the upper slope is steep enough, a ridge board can work. However, a ridge beam is better for taller mansard roofs with a more complex design.

Shed Roof (Skillion Roof)

✔ A single sloping plane
✔ Support needed: No ridge component needed

Since a shed roof doesn’t have two sides meeting at a ridge, it doesn’t require a ridge board or beam. This simple, modern design is popular in minimalist architecture.

A-Frame Roof

✔ Steep triangular shape (resembles an “A”)
✔ Support needed: Ridge beam

A-frame roofs are built with extreme angles and require strong support from a ridge beam to prevent sagging. This design is common in cabins and vacation homes.

The Importance of Professional Assessment

Understanding the basics of ridge boards and beams is helpful, but roofing is not a DIY job. A poorly supported roof can lead to sagging, leaks, and costly repairs down the road. Consulting a professional ensures your roof is safe, durable, and built to code.

A qualified contractor or structural engineer can:

• Evaluate your roof’s needs based on its design and load requirements
• Ensure compliance with local building codes and safety regulations
• Recommend the right ridge component to prevent structural issues
• Oversee proper installation so your roof lasts for decades

Cutting corners on your roof’s structure can lead to serious long-term problems. Hiring a pro from the start saves money and protects your home.