Ridge Beam Support Options for Stronger Roofs

A strong roof is crucial for any building, and one key component that ensures its stability is the ridge beam. In fact, a well-designed ridge beam can support up to 50% of the roof's weight.

The ridge beam is the longest beam in a roof, running along the peak where two slopes meet. Typically, it's made of wood, but can also be constructed from steel or other materials.

To provide additional support, ridge beam hangers can be installed at regular intervals, usually 16 to 20 inches apart. This helps distribute the weight evenly and prevents the beam from sagging or collapsing.

By choosing the right ridge beam support option, you can ensure your roof remains sturdy and secure for years to come.

A structural ridge beam is a crucial element in supporting the weight of your roof, and choosing the right size is essential to ensure it can handle the load. For our example log cabin, we assumed a total load of 30 psf, which translates to 390 plf (pounds per linear foot) on the ridge beam.

To determine the required size of the LVL (laminated veneer lumber), we consulted the table under the "Span" column and found that a 3 ½" x 11 ¼" LVL beam can carry 407 plf, making it a suitable option.

In some cases, you may need to double up two LVLs to achieve the desired load capacity, as was the case in our example where we needed to order four 1 ¾" x 11 ¼" LVL beams to make up the structural ridge beam.

When installing the LVL, it's essential to ensure a minimum of a 4" x 4" bearing surface is provided over the center joint, as per the bearing requirement. This will help distribute the load evenly and prevent any potential issues.

If the width of the ridge beam is not sufficient to accommodate the angled cut on the upper rafter ends, you can fill in the bottom with a 2" x 4" to prevent the rafter from twisting.

Structural Considerations are crucial when it comes to ensuring the integrity of your roof. A dead weight of 10 psf and a live weight (snow load) of 20 psf can result in a total load of 30 psf, as seen in our example log cabin.

The span of the roof is ½ of the width, so 26’/2 = 13’, and the length is ½ of the overall length, so 36’/2 = 18’. This results in a total load per lineal foot of 390 plf, which must be supported by the ridge beam.

To ensure the correct size of the LVL, you need to check the allowable uniform loads under the left-hand column labeled “Span” and find the row corresponding to the 18’ span. The largest single 1 ¾” x 14” LVL beam will only carry 386 plf, so doubling up two 1 ¾” x 11 ¼” LVLs is required.

Here's a breakdown of the required LVL beam sizes:

It's essential to provide adequate tie-down connections between the ridge beam and its supports to resist wind uplift forces from rafters. Steel strap ties or wood side-pieces extending up alongside the ridge beam from the ridge supports or columns can be used.

Strengthening stick-frame roof connections is crucial for building safer and stronger homes. Using connectors can simplify construction and eliminate complicated toenailing.

Connectors provide a tested means of making critical connections, which can be challenging to consistently install correctly with toenailing. They also offer more reliable load paths and can be used in certain applications where traditional methods are not possible.

In a cathedral ceiling, for example, rafters require a secure connection to the ridge beam. A connector like the HHRC field-slopeable connector can be used to attach hip and roof beams to the end of a ridge beam, accommodating heavier hip loads and achieving optimal allowable loads.

Using connectors can also help improve job efficiency by eliminating mismatched angles in the field and lead times associated with special orders. The LRUZ face-mount rafter hanger, for instance, can be installed either before or after the rafter is in place, and its field-adjustable seat helps improve job efficiency.

To ensure a strong and secure roof connection, it's essential to consider the load path and provide adequate tie-down connections between the ridge beam and its supports. Steel strap ties or wood side-pieces extending up alongside the ridge beam from the ridge supports or columns can be used to resist wind uplift forces.

Here are some common types of connectors used in stick-frame roof connections:

These connectors can be used in various applications, including cathedral ceilings and roofs with heavier hip loads. By using connectors, builders can ensure a stronger and more reliable roof connection, which is essential for building safer and stronger homes.

Calculating the size of a structural beam is crucial to ensure the stability and safety of a building.

To determine the required load conditions, clear opening, and span of the trusses or other members framing into the header or beam, you'll need to consider the design roof snow load, dead weight, and live weight.

The design roof snow load is derived by reducing the ground snow load in accordance with the provisions of Section 7.3 in ASCE 7-10. For example, a design roof snow load of 0.70 times the ground snow load, with a required minimum of 20 psf, is used in the size selection tables.

You'll also need to calculate the total load per lineal foot that the ridge beam needs to support, taking into account the dead weight and live weight. For instance, a total load of 30 psf was used in Example 2.

The Southern Forest Products Association's span tables for Southern Pine headers and beams provide an easy method for selecting the proper Southern Pine header or beam for its intended application. These tables are based on standard engineering formulas for beams supporting uniformly distributed loads.

Here's a summary of the four design parameters considered in the span tables:

By considering these parameters and using the span tables, you can determine the required size of the structural beam to support the loads and ensure the stability of the building.

Hanging rafters from the ridge beam can be a bit tricky, but with the right approach, you can get it done efficiently. You'll want to balance the installation by matching rafters on both sides as you work along.

It's essential to install several matching pairs spaced out along the ridge beam span to keep it straight. Then, you can go back and fill in the remaining rafters.

You can hang rafters from the top or from the bottom, using two different types of rafter hangers. Top rafter hangers are installed 24" o.c. before doing anything else.

Using bottom rafter hangers, you'll hold the rafter in position and nail it through the top edge to hold it, then install the hanger by pushing it up flush on the bottom and nailing.

For top rafter hangers, you'll need to use 1 1/2" long 9-gauge galvanized nails that won't split out the opposite side. These nails are specifically designed for rafter hangers.

It's worth noting that top rafter hangers can be a challenge if your ridge beam isn't thick enough for two hangers meeting on top. In this case, you may need to adjust your installation strategy.

Specialized nails like positive placement nailers or palm nailers can make the job faster and more efficient.

Glued laminated timber headers and beams are stock items that can be purchased from a local building material supplier. They're available in a variety of standard widths and depths, strength combinations, unbalanced or balanced beam layups, cambered or non-cambered beams, four different appearance grades, and stock or custom members.

A common type of glulam timber is the unbalanced layup, which has a distinct top and bottom. This means there's a clear "TOP" mark on the beam, and it must only be used with the "TOP" mark facing up.

Using an unbalanced glued laminated timber upside down or in a continuous span across supports can cause a strength reduction. An appropriate balanced beam combination, such as 24FV5, may be used for either simple-span or continuous span applications.

Georgia-Pacific Engineered Lumber is made from high-grade wood fiber and specifically formulated resins, producing virtually defect-free engineered lumber.

This manufacturing process enables G-P engineered lumber to resist shrinking, twisting, and warping, making it more consistent and having more load-carrying capacity and spanning ability than regular sawn lumber.

LVL, or laminated veneer lumber, is an engineered beam made up of multiple plys of wood, with all strands oriented in the same direction, giving it enormous strength vertically.

However, this also means the LVL is quite flexible side to side until the rafters are installed and stiffen it laterally.

To use Georgia-Pacific Engineered Lumber for a structural ridge beam, it needs to be installed on edge with the flat side running vertically, which can actually make it easier to install.

The LVL can be passed up by hand, resting it on top of the log walls or scaffolding and bending to rest on the next support, and then rotated until it's on edge and becomes very rigid.

The "Roof 115% (Snow)" chart on page 44-45 in the GP booklet is used to determine the load-carrying capacity of the LVL, and it's essential to use the "Non-Snow" chart only if the roof angle is greater than 54 degrees to ensure no snow builds up on the roof.

Glued Laminated Timber is a type of engineered wood product that can be purchased from a local building material supplier. It's available in various standard widths and depths, strength combinations, and appearance grades.

You can find glued laminated timber headers and beams in stock, or you can order custom members. Some common combinations use an unbalanced layup of laminating lumber grades, which means there's a distinct top and bottom to the beam.

All unbalanced glued laminated timber stock beams must have a "TOP" mark and should only be used with the "TOP" mark facing up. Installing an unbalanced beam upside down or in a continuous span across supports can cause a strength reduction.

Some stock glulam timber is manufactured with camber, while others are made without it, especially balanced layup combinations. If you're unsure about the specifics of a particular product, it's best to contact APA – The Engineered Wood Association or the Pacific Coast Lumber Inspection Bureau for more information.

If you're building a log cabin with a cathedral ceiling, you need to know about structural ridge beams. A structural ridge beam is much stronger and more stable than a conventional ridge board held in place with rafters.

For roof loads, the LVL (laminated veneer lumber) carries the weight and transfers it down the load path via end supports and posts.

In conventional construction, a ridge board is used for ease of construction, but it's not suitable for roof slopes less than 3 on 12.

A structural ridge beam is required for roof slopes less than 3 on 12, according to the International Residential Code (IRC) and International Building Code (IBC).

You can use a structural ridge beam when installing structural insulated panels, or SIPs, on a cabin roof.

To find more information on building codes, check out the International Building Code and International Residential Code, available on Amazon.

Here are some key differences between a ridge beam and a ridge board:

Using a structural ridge beam can save you from costly repairs down the line.