Deck Framing

Steel Deck Framing

When wood deck framing fails, the next logical material to consider is metal. Steel is a common choice.

• The least expensive metal deck framing option
• Stronger and more durable than wood
• Resists warping and twisting
• Resists decay and insects
• Non-combustible
• Allows for long cantilevers
• 50-year lifespan

However, steel deck framing does have a few downsides:

• Extremely heavy
• Susceptible to corrosion; cannot be installed within 3000 feet of saltwater bodies
• More expensive than wood framing

Shop Steel Deck Framing

LVL Deck Framing

Laminated Veneer Lumber (LVL) is an engineered wood product that combines the strength of multiple thin layers with the durability of pressure treatment. Think of it as a heavy-duty form of plywood.

• The least expensive alternative framing option
• Stronger and more durable than modern pressure treated pine
• Resists warping and twisting
• Resists decay and insects
• When properly flashed with joist tape, can last up to 25 years

Composite Deck Framing

Composite deck framing, like composite decking, is made from a mixture of wood fibers and recycled plastic. It comes with all the same advantages and disadvantages as the composite decking it’s based on.

Pros:

• Low-maintenance
• Resists decay, insects, and warping

Cons:

• More expensive than wood or steel
• More flexible than wood or metal
• Can only accomodate short cantilevers

Aluminum Deck Framing

Aluminum is a higher-end metal deck framing option. It has all the mechanical advantages of steel, but without many of steel’s drawbacks.

• Stronger and more durable than wood
• Resists warping and twisting
• Resists decay and insects
• Lightweight
• Resists corrosion, and can be installed near saltwater
• Non-combustible
• Allows for long cantilevers
• 50-year lifespan

However, aluminum is also the most expensive alternative deck framing option.

Pressure Treated Deck Framing

Pressure Treated Pine has long been the go-to for deck framing, but that’s starting to change. The quality of pressure treated products has dropped in recent years, resulting in decks that are less durable.

This degradation is caused by a variety of factors:

• The use of different chemical treatments that are safer for people and the environment, but aren’t as good at protecting the wood
• The use of younger trees that yield softer timber

Where once a pressure treated deck frame could be expected to last 25 years, that life expectancy has dropped to 10 years or even less! In short, pressure treated deck framing is not what it used to be. Because of this, many builders are turning to alternative framing options.

Deck Joist Size Calculator

This calculator will tell you what size (thickness x height) joists you need based on the spacing of your supporting beams (“beam spacing” or “clear span”) and the spacing of the joists themselves (“joist spacing”). It will give you the smallest joist size that will work for your specifications. You can reduce the required joist size by adding more supporting beams, thereby reducing the beam spacing and shortening the clear span, or by using a tighter joist spacing.

Deck Joist Span Charts

Deck Beam Span Charts