Ridge Beam Support Post Materials and Installation Guide

When choosing materials for your ridge beam support post, consider using pressure-treated wood, such as Southern Yellow Pine or Hemlock, which can withstand the elements and last longer.

Pressure-treated wood is a popular choice due to its durability and affordability, often costing between $10 to $30 per linear foot.

For a more rustic look, you can opt for reclaimed wood, which can add character to your structure, but keep in mind it may require more maintenance.

Reclaimed wood can be sourced from old barns, fences, or other structures, and can cost anywhere from $20 to $50 per linear foot.

When selecting the right size for your support post, ensure it's at least 8 inches square and 8 feet tall to provide adequate support for your roof.

A structural ridge beam is a must-have for certain types of roofs, like those with slopes less than 3 on 12 or cathedral ceilings in log cabins.

The International Residential Code (IRC) and International Building Code (IBC) require independent support for the high ends of rafters, which is where a structural ridge beam comes in.

Using a structural ridge beam allows you to span long distances and provides a stronger and more stable roof than a conventional ridge board.

The roof loads are carried by the LVL (laminated veneer lumber) and transferred down the load path via end supports and posts.

A structural ridge beam is supported on both ends, which means the rafters are supported independently of each other by the ridge beam itself.

This prevents the bottom ends of the rafters from pushing out and causing the roof to collapse, especially in cases where there's no attic floor or ceiling joists.

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

When designing a ridge beam support post, it's essential to consider the structural load it will bear. The total load per lineal foot (plf) that the ridge beam needs to support is crucial in specifying the correct size of the LVL.

The span of the roof is typically ½ of the width, and the length is ½ of the overall length since an intermediate post is used. For example, a 26’ deep and 36’ long log cabin with a supporting post halfway along the length of the cabin would have a span of 13’ and a length of 18’.

To calculate the total load, multiply the square footage of the roof by the total load per square foot (psf). In our example, the total load is 7020 lbs, which is calculated by multiplying 234 sq ft by 30 psf.

The total load must be met or exceeded by the allowable uniform loads listed in the LVL beam specifications. For an 18’ span, the largest single 1 ¾” x 14” LVL beam will only carry 386 plf, which is not enough. A 3 ½” x 11 ¼” LVL beam, however, can carry 407 plf.

To achieve the required load, you can use two 1 ¾” x 11 ¼” LVL beams, which are then doubled up to make up the structural ridge beam. This method is stronger than using a conventional ridge board supported by rafters.

The center joint of the LVL beam must be located over a minimum of a 4” x 4” bearing surface to meet the bearing requirement. Additionally, if the width of the ridge beam is not high enough to accommodate the entire angled cut on the upper rafter ends, you should fill in the bottom where the heel of the rafter rests with a 2” x 4” to prevent rafter twisting.

To resist wind uplift forces from rafters, you must 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 for this purpose.

Ridge Beam Design Requirements:

Note: The allowable uniform loads listed are for a 3 ½” x 11 ¼” LVL beam.

For a ridge beam support post, you'll need to choose the right materials to ensure it's sturdy and long-lasting.

The most common materials used for a ridge beam support post are pressure-treated lumber and galvanized steel.

When selecting materials, consider factors such as durability, weight capacity, and weather resistance.

A typical ridge beam support post is made from 4x4 or 6x6 pressure-treated lumber, which can withstand heavy loads and harsh weather conditions.

Steel posts are a popular choice for fencing and other outdoor structures due to their durability and low maintenance requirements.

They can withstand harsh weather conditions, including high winds and heavy rainfall, and require little to no upkeep.

Steel posts are typically made from galvanized steel, which provides a protective coating against rust and corrosion.

This coating helps extend the lifespan of the post and reduces the need for frequent replacements.

A standard steel post is usually 3-4 inches in diameter and 8-10 feet tall, but can vary depending on the specific application and design.

They are often used in combination with wooden or metal fencing materials to create a sturdy and long-lasting fence.

The installation process for steel posts involves digging holes for the posts, setting them in concrete, and securing them with wire or brackets.

Proper installation is crucial to ensure the stability and safety of the structure.

The depth of the hole should be about 12-18 inches, depending on the type of soil and the weight of the post.

This will help prevent the post from shifting or toppling over in strong winds or heavy loads.

Concrete should be poured around the post to provide additional support and stability.

The concrete should be allowed to set and cure before the post is secured with wire or brackets.

Georgia-Pacific Engineered Lumber is made from laminated veneer lumber, or LVL, which is an engineered beam composed of multiple layers of wood. This makes it extremely strong in one direction but not the other.

Georgia-Pacific's engineered LVL's are virtually defect-free and resist shrinking, twisting, and warping due to a manufacturing process that combines high-grade wood fiber with specific resins.

Using LVL for a structural ridge beam requires installing it on edge with the flat side running vertically, providing enormous strength vertically but making it flexible side to side until the rafters are installed.

This flexibility can actually make it easier to install, allowing you to pass the LVL up by hand and resting it on top of log walls or scaffolding before rotating it into place.

To use the "Non-Snow" chart, the roof angle would have to be greater than 54 degrees to ensure no snow builds up on the roof.