what is a beam on a deck

A deck beam is a board or collection of boards that support the deck joists and decking. Beams are made out of a variety of treated dimensional lumber

. They may be a single plank, or consist of two, three, or even four 2x8s, 2x10s, or 2×12 boards fastened together with bolts or nails.

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How to install deck beam?

Installing Beams for Cut Corners

• Run the inside front beam (3) into the backside of the front beam (2) this allows more fasteners to help secure beam (2).
• Install a 4x4 spacer block between the beams to help secure beam (4)
• Miter the end of beam (4) to fit snugly into the back face of beam (3).

How to support deck beams?

Working with Pressure-Treated Lumber

• Use fasteners and hardware labeled for treated lumber — stainless-steel or hot-dipped, galvanized screws.
• If the lumber is wet — it typically is when delivered from the store — butt it together tightly when building. ...
• Drill pilot holes in the ends of boards to prevent splitting when you nail or screw them together.

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How far can a deck beam span?

When the deck joists are 8 ft. long, the beam can span 7-7. When building a deck with 7-ft. joists, you know the beam can span somewhere between 7-7 and 8-0, but you don’t know exactly where. Check with your local code official, or simply drop back to the shorter value in the table and assume the allowable span is 7-7.

What is deck support beam?

Deck support beams are a critical ingredient to making your deck safe for years to come. An improperly supported deck can result in collapse – there’s a reason deck codes exist and you don’t want to invite thirty people over to a barbecue to find out that your deck can’t support that many people.

Do I need a beam under my deck?

Beams are a crucial part of any deck, so it's imperative that they're properly installed. A beam runs across the posts, parallel to the ledger, and supports the joists.

What are beams on a deck called?

Joists. Joists are one of the most prominent parts of the anatomy of a deck as provide structural support to your deck floor. Joists are installed between beams and are typically spaced at 16” on center, but can be spaced 12” for a sturdier foot feel.

How do you build a deck beam?

How to Build a Deck Beam.Step 1: Stack and Square Deck Beams.Step 2: Cut and Attach Spacers.Step 3: Clamp and Screw Deck Beams Together.Optional: Sandwich a Post Between Beams.Step 4: Drill Holes for Bolts.Step 5: Tap in Bolts.What to Do if the Deck Is Too Close to the Ground.

What is a single deck beam?

What is a Deck Beam? A deck beam is a board or collection of boards that support the deck joists and decking. Beams are made out of a variety of treated dimensional lumber. They may be a single plank, or consist of two, three, or even four 2x8s, 2x10s, or 2×12 boards fastened together with bolts or nails.

What are parts of a deck called?

Parts of a DeckFlashing. Flashing is a sheet of material cut into strips and affixed over any cracks, joints, or exposed areas to prevent moisture from getting through. ... Ledger. The ledger is the most important part of the frame of the deck. ... Joists. ... Rim Joists. ... Bridging. ... Railing Posts. ... Footings. ... Support Posts.More items...

How do you support a deck beam?

3:336:00Options for Fastening Beams to Deck Posts - YouTubeYouTubeStart of suggested clipEnd of suggested clipYou can drive some through bolts all the way through the holes that are provided. That will giveMoreYou can drive some through bolts all the way through the holes that are provided. That will give some additional support. You would just look at the load tables for the piece of hardware.

How far apart are deck beams?

How wide apart should decking joists be? In North America, joist spacing for residential decks is 12″ to 16″ apart, or according to local building code. Most decks require 16″ spacing for the deck itself, with 12″ spacing used for special applications, such as stairs or commercial structures.

How do you make a beam?

0:342:04DIY Shed AsktheBuilder How to Make a Wood Floor Beam - YouTubeYouTubeStart of suggested clipEnd of suggested clipRight about in the center of that 12 footer and then all we're going to have to do is cut upMoreRight about in the center of that 12 footer and then all we're going to have to do is cut up approximately two six-foot pieces at the end to make this one the twenty.

What is a built up beam?

built-up beam on a post. 1. A beam made of structural metal units (such as plates and angles) which are riveted, bolted, or welded together. 2. A beam of precast concrete units which are joined by shear connectors.

How thick should a deck beam be?

Now, deck beams with a thickness of 2” are acceptable, giving you the option to double up or triple up the boards to create beams at the job site from 2×6, 2×8, 2×10, or 2×12 lumber depending on your construction plan.

How can I make my deck stronger?

2:054:34Build a Safe, Strong Deck - YouTubeYouTubeStart of suggested clipEnd of suggested clipThe wood joists. Should always be attached with metal joist hangers to the ledger and at the otherMoreThe wood joists. Should always be attached with metal joist hangers to the ledger and at the other hand when the wood joists run over the beam they should be secured with hurricane ties or clips.

What size beam do I need for an 18 foot span?

Thus, for a 18 foot span, you will need atleast 3-2×16 or 6×16 size of wood beam. For a 18-foot spans, the wood beam has to be at least 16 inches in depth and 6″ in width (3-2×16) used for residential building, wood frame structure or projects.

What is a fascia board on a deck?

A DECK FASCIA BOARD is the board that runs around the perimeter of the deck for a seamless look. Fascia covers the wood perimeter joist of the deck frame and is sometimes called “rim joist cover.”

What are the parts of a deck frame?

Components of the DeckFooting. - Most decks begin by pouring concrete footings and attaching post anchors. ... Post. - Posts are attached to the footings and hold the support beams up off the ground. ... Beams. ... Joist. ... Ledgers and header joists. ... Deck boards. ... Drainage system. ... Hidden fasteners.More items...

What is a deck ledger?

The deck ledger is the deck floor rim board attached to the house, and it should be positively connected to the floor structure of the main building with bolts or lag screws, not nails. The main objective of this article is to alert property owners and code officials to decks with “nailed-only” deck ledger connections.

What is a deck rim joist?

Rim joists are the perimeter joists of a deck. The two outside parallel joists, plus those that run perpendicular to all the joists, form the rim of the deck or a band that ties the structure together. Hence, they are known collectively as band boards and rim boards.

How wide is a post and beam deck?

Sorry. Instead of lots of skinny sticks and plywood panels, decks use thicker 4×6 (and 6×6) posts and stronger beams that span openings 6 or 8 feet wide and 8 or more feet high to create an open frame. And most of that frame is below the deck floor, so you get great views from your deck. Here’s the frame of a simple Post and Beam deck:

What is post and beam?

Post and Beam puts a double (or even a triple) beam under the joists, where it supports the joists directly. Joist hangers become unnecessary. Wood joists on top of the wood beam are inherently strong. A carpenter can screw each joist to the beam below, so it cannot slide.

How deep should a girder deck be?

Thus, for example, #2 Pressure Treated 2×8 joists, placed 12” apart, can safely span 13’ 6” out.3 To make your Girder deck larger, say, 16 feet deep, you must upgrade your joists to 2x10s, which adds considerable cost. But the joists in Post and Beam sit on top of the beam, so you can keep the beam at 13’ 6” and extend the joists 2’ 6” further to reach the 16 feet you want.

How many footings are needed for a post and beam frame?

Thru-Post or Girder frames require 5 footings here, but Post and Beam solves this configuration with only 3 footings.

What do decks want?

Backyard decks want an airy feel, they want to bring you close to your yard, close to nature.

What is OSB sheathing?

Plywood (or OSB) sheathing reinforces and ties the stick framed walls together. And there are variations: Balloon framing, Structural Insulated Panels (SIPs), even modular houses built in a factory….

Is the shallow notch stronger than the full notch?

Choose your poison: The full notch is strong vertically. But it is horribly weak laterally. The shallow notch is stronger laterally, but fails in its primary purpose — supporting the weight of the deck and people.

What are the beams on a deck?

Beams are an essential part of a deck's support system, so if you're building your own deck, you want to make sure these elements are as sturdy and long-lasting as possible. Many older decks were built using massive timbers, such as 4x6s or 4x8s, for beams, which support the underside of the deck horizontally.

How to build a beam?

Instead of stacking three beams on top of each other, sandwiching deck posts between two 2x10s is another common way to build a beam. Begin by cutting your posts about 1 foot longer than needed. Set them in place with temporary support. Position the members and fasten them with carriage bolts.

How to make a flush beam?

The solution is a flush beam, which is essentially a header that has been doubled for strength. Cut two headers (the boards that will be perpendicular to the joists) and mark lines on them indicating where the joists will go. Fasten them to the posts so they are level. Double up the headers to make them flush beams.

How many 2x10s are needed for a deck beam?

A singular deck beam saves time, but fashioning your own out of three 2x10s will create a stronger, longer-lasting beam for your DIY deck.

Can you use 2 inch thick lumber to make a beam?

Alternatively, fastening multiple pieces of 2-inch-thick lumber together can create a beam that is stronger than a single piece of 4-inch or 6-inch lumber.

Can you attach a beam to a post in Washington State?

In Washington state, building code since 2015 does not allow the beam attached to posts in sandwich method. The beam must rest on top of the post by notching or (engineered) post cap hardware. That spec comes from the IRC. New info to me, passing it on ...

How to nail a beam?

Nail them at an angle so the point of the nails won't go through the beam. Reverse the angle of the nails at the ends of the beam to lock it into place for strength. Start at about 4" from the ends of the beam. Nail both sides of the beam. Do not use screws.

How many nails do you need to join 2x10 beams?

A 2x10 Beam should use a minimum of (4) - 3” nails fastened in a vertical pattern from both sides of the beam every 16” on center. Be on the safe side when in doubt and use extra nails, ...

What is a header beam?

A flush or header beam is a structural member positioned at the same level as the joists and uses joist hangers for attachment just as you would at the ledger board.

Why do you need flush beams on screened porches?

Screened porch frames must use flush beams in order to transfer roof loads effectively to the footings placed at the edges of the deck. Overall flush beams perform below the standard of cantilevered beam construction because a composition of hangers and fasteners are less reliable than the positive connection of wood directly supported by wood.

What determines the force that bears upon a beam?

The length of joist span actually supported by a beam is what determines the force that bears upon that beam and therefore the distance that a given size of beam can span before another post is required to support that beam.

How to determine the length of a joist supported by a beam?

Determine the length of the joist actually supported by the beam. This distance is half the distance to the next beam in either direction. If a joist is attached from a ledger to a beam, then the distance is the midway point between the supported ends (either a ledger or beam) of the joist plus any cantilevered portion of the joist past the beam.

How to determine beam span?

For determining beam spans (distance a beam can span between supporting posts), consider the following concept. The more weight, or the longer the supported length of joist that a beam must carry, the shorter the span of the beam – for a particular size of beam.

How far should a 4x6 beam span?

Obviously, the larger the beam, the greater the distance it can span between posts. A Redwood 4x6 beam should span no more than 6' between supporting posts. Beam Span Table. Beam Span between Posts or Ledgers. Wood Species.

What Is a Beam?

A beam is the main load-bearing element for the structural soundness of your deck’s roof. It’s not only responsible for supporting the weight of the joists, but other building elements, as well.

What is a joist in a deck?

Joists are the repeated structural members that are used to build a deck frame. The minimum size joist to be used in deck construction depends on the number of footings and beams that will be installed.

What is center to center spacing for deck joists?

The layout term for joists is “On Center,” which is the center-to-center measurement from one joist to the next. Most decks use 16" on center spacing for joists. Most decking is not strong enough to support longer spans than 16". Some builders reduce joist spacing to 12" on center to strengthen the deck frame or to increase maximum allowable joist spans.

What is a joist hanger?

Joist hangers are used to attach the ends of joists to the face of a beam or a deck ledger board. If you identify a crown in the board, you should always install it upwards. The crown will eventually settle after completing construction and should stiffen in the proper position after drying.

How far apart should joists be on header?

Marking joist locations at 16" on center spacing on the header with a marker.

Why is it important to have a deck?

And while it’s important to have a deck that’s aesthetically pleasing to you, the most vital part about your deck is making sure it’s structurally sound. That includes knowing the difference between a joist and a beam and what purpose they serve to your deck and its functionality and safety.

Can you stretch a string across a composite deck?

This can sometimes cause an uneven surface. That’s why stretching a string across the joist spacing for composite deck boards can help detect spots that may be higher than others. These spots can be addressed with a power hand planer to give you a nicer, smoother surface for the deck of your dreams.