What size joists should I use for decking?
What Screws Should I Use for Decking?
- Types and Sizes of Decking Screw. Deck Screw is a crucial and essential part of decking. ...
- Things to Consider Before Choosing Deck Screw. One of the biggest mistakes people often make when building a deck is to save money with low-quality screws.
- Conclusion. ...
How far can you span a 2x6 deck joist?
The maximum distance a 2×6 can span, according to the 2018 IRC, for a floor joist, is 12’-6”, ceiling joist 20’-8”, rafter 18’-0”, deck board 24”, deck joist 9’-11”, deck beam 8’-3”, and 6’-1” as for header. Always check the codes for determining factors or consult a Structural Engineer.
How wide should the floor joist be for a deck?
Tips for Properly Installing Composite Decking Joists
- Make sure your joists are as level as possible. As you’re installing them, run string lines across the tops of the joists frequently. ...
- Support your joists with blocking. ...
- Check for protruding nails and screws. ...
Can I use 2x6 for deck joists?
One can use 2×6 for deck joists depending on where they want to put the deck. If the deck is going to be put near the ground, 2×6 joists may work perfectly. In other cases, it might not give much strength. Even the spanning of the deck joist must be considered, which would be 16 inches.
How many joists do I need for a 12x12 deck?
For example, a 12-foot x 12-foot deck of 5/4 x 6 pressure treated wood decking on 16 inches on center spacing of joists will require: A 12-foot long deck with joists 16 inches on center will require 10 joists.
Can deck joists be 24 inches on center?
Softwoods should be at least 1 1/4 inches thick for a 16" on center span. 2 inches thick will allow for a 24" on center span.
How far apart should Supports be for a deck?
Ideal deck post spacing is 8 feet or less. The distance between deck support posts depends on the type of wood species used and the size of the joist and beam. There is no minimum span, and maximum spans can reach up to 15'.
Can you use 2 by 6 for deck joists?
You can use 2×6 as deck joists if the deck is low enough to the ground as not to require guard railing. When using S-P-F 2×6 deck joists, the span must not be greater than 9'0″ (2.73m) with joists at 16″ o.c. (400mm), and 9'10” (3.01m)with spacing at 12″ (300mm).
Can I use 4x2 for decking frame?
4 x 2 Timber Rail / Joist. Pressure treated timber joists. These decking joists are the most common sized framing timber for decking. They provide a solid structure for fixing your decking boards too.
How far apart should decking joists be UK?
Decking joists should be spaced at 400mm centres. Structural posts should be positioned no more than 1800mm apart. Use a joist and spirit level to mark the ledger height at the wall. Joists are attached to the ledger or double beam with galvanised joist hangers.
How many joists do I need for decking?
For example, when you space joists 16″ apart — which is standard for residential decks — a deck spanning 9 1/2′ would require 2-by-6 joists, a 13′ deck would need 2-by-8 joists and a 16′ deck calls for 2-by-10 joists.
How far apart are beams for a deck?
How to Space Deck Beams. To properly space deck beams, you need to consider the joist span. The limitations of how far a joist can span determines just how many beams you'll need. Joists spaced the standard 16 inches apart can span 1.5 times their depth in feet.
What size bearers and joists for a deck?
The bearers have to carry the weight of the entire deck and whatever is put on top of it, so they need to be strong. A 140×45 treated pine bearer will usually do the trick. Every 1.2 metres, a 90×90 H4 treated pine post will be needed. Treated pine is the easiest to work with.
How far can a 2x6 decking span without support?
How Much Weight Can a 2×6 Support Horizontally? A 2×6 can support up to 50 pounds per square foot of weight without sagging with a maximum span of about 12 feet when spanning a distance horizontally, with the 2×6 standing in a vertical position. This number includes both live and dead weight.
Should I use 2x4 or 2x6 for deck?
Most builders stick to using a minimum of 2x6s for deck floor joists. If you want to add guardrails and stairs, you need at least 2x10s. 2×4 and 2×6 joists are ideal for ground-level decks without guards.
Which deck is better 2x6 or 5 4?
Many professional deck builders prefer to use 5/4 decking as it is lighter, less expensive, and typically of better quality and appearance than 2×6 decking. Additionally, they also prefer joists spaced at 16” O.C. for strength and durability, regardless of lumber dimensions.
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 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.
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.
Do you need to install stair stringers on composite decking?
If you are installing composite decking over an existing frame, you may need to install new intermediate joists or stair stringers to meet the installation requirements. Since most composite products aren’t as inflexible as their wood counterparts, they don’t hide imperfections in the framing quite as well.
How many inches between joists for composite decking?
Most composite and PVC decking brands, like Trex and Azek, recommend a maximum joist spacing of 16 inches OC. Some brands, like WearDeck, let you get away with more – reinforced with a layer of fiberglass on both the top and bottom, WearDeck boards easily allow for spans of 24 inches OC.
Why is joist spacing important?
If the floor joists that span the length of your deck are installed too far apart, the boards on top will sag. If the joists are not all the same exact height, the deck’s surface will be uneven.
Why do composite decks last longer?
Composite decking, which is made from a combination of wood and plastic, lasts longer than traditional wood because it’s less prone to rotting, splintering, and insect damage. But to truly get the most out of your new composite deck, you have to start with a strong frame. Composite decking brands like Trex and TimberTech generally have their own ...
What happens if you space joists too close together?
However, if you space your joists too close together, it will be difficult to install supporting elements such as joist hangers, blocking, and flashing .
What does "on center" mean on deck joists?
What Does “On Center” Mean? The distance between two deck joists is measured in inches “ on center”, commonly abbreviated as “OC”. If you were to draw a line down the center of two joists and then measure the distance between them as 16 inches, that measurement is 16 inches on center.
How much OC do you need for composite?
Composite materials have changed drastically over the years, improving in both performance and appearance. At the same time, local building code requirements have also become stricter. For example, towns that once required a maximum of 16” OC for composites may now require 12” OC.
Can you use hidden fasteners on composite decking?
For a cleaner finish, use hidden fasteners to install your composite deck boards instead of screws. Finally, you can add the finishing touches – posts, railing, skirting, and anything else you can dream of. From frame to finish, Decks & Docks has everything you need to complete a composite decking project.
What happens if a deck isn't level?
Joists that aren’t level can result in high or low spots throughout the deck, resulting in a wavy-looking deck. TimberTech decking will conform to the contour of the joists to which it is attached. DOUBLE CHECK YOUR LEVELING.
What is required to secure existing framing?
Ensure the framing is held with exterior-grade fasteners; additional exterior-grade fasteners may be required to secure existing framing, as well as fastening reinforcement. Inspect framing for contraction of structural lumber and ensure all fasteners are sound and showing no signs of corrosion.
Why should I block wood edge to edge?
Blocking should be installed edge to edge to allow for fastening of the interior blocking. WHY BLOCKING MATTERS. Solid wood blocking helps reduce up or down movement and the twisting of joists. Limiting joist movement also helps prevent gapping between deck boards for a uniform finish.
Do you run string line before installing decking?
Before installing any decking, run string line frequently to ensure that the tops of the joists are in plane and level. While a particular joist may be level itself, the top of that joist may still not be in plane with surrounding joists.
Do you need extra framing for deck boards?
Different deck board patterns can require extra blocking / framing (for example, picture frame borders or diagonal inlays). Confirm your design and planned orientation of your deck boards before you begin deck joist work.
How Far Can Floor Deck Joists Span?
The length of a joist defines the deck joist span. For example, the maximum span length of a Douglas fir-larch, 2×12, supporting a 40 (PSF) live load and 10 (PSF) dead load, with 12″ spacing, is 18 feet 3.
Is There a Standard Floor Joist Span?
Because every house is unique, there is no standard floor joist span. There are just too many variables present to establish a standard for floor joist span.
Deck Cantilevers Explained
A deck cantilever is a deck section that projects out beyond the supporting joists. You can use this to create a covered porch or extended seating area. The maximum cantilever distance is 4 foot 6 inches, but it’s best to keep it within 2 feet for most decks.
Conclusion
Deck joist sizes and span can be a complicated subject, but we’ve done our best to simplify it. You can use these tables to determine deck joist sizes, spacing, and span based on wood species.
What will attract you first when choosing a composite decking?
What will attract you first when choosing a composite decking is the colors. The other best thing about these products is how they require low maintenance with less surface treatment.
Why is composite decking not safe?
For instance, a wet composite surface is not safe, especially on pool sides. The reason is that the material has a composition of oil-based plastic.
What gives composite decking a soft texture?
What gives the composite decking a soft texture is that it contains more plastic than wood fiber. With such a surface, you’ll realize that sanding is not an option as in wood. The only best solution is to replace the board completely. Other problems with the composite decking include. They aren’t natural.
Why is my deck shrinking?
If your deck is constantly exposed to moisture, you’ll realize some effects such as shrinking, warping, shifting, swelling, and many more. All these are caused by the composite nature of the deck that lets it be more sensitive to humidity, temperature, and sun exposure.
Why does moisture get in my deck?
With a waterproof surface, the water may not get absorbed. In such a scenario, it becomes stagnant hence causing mold growth. It even becomes worse if you live in areas with high humidity.
Can you use butt joints on composite decking?
Also, it’s not recommended to use butt joints on composite decking due to the significant thermal movement.
Can composite decking be used on wood?
Yes, composite decking is ideal for wooden joists, especially when you are working on your decking. Even so, ensure you go for the pressure-treated joists for durability purposes. Also, work on a strong foundation that can withstand the deck’s weight.
How far apart should deck joists be?
The spacing of your joists indirectly affects how far apart you place your deck support posts. For example, most decks have joists that are spaced 16” on center. However, if you opt to space your joists only 12” on center you can have a much longer deck span – up to 2’ longer.
How far off the ground can you use 4x4 deck support?
4×4 deck support posts cannot be used if a deck is more than 5’ off the ground. Some jurisdictions do not allow them at all, so check with your local building services office. 6×6 support posts require a minimum of 10” diameter footings. Beams must sit on top of deck support posts, using code-approved fasteners.
What does a deck beam span tell you?
What they do tell you is the maximum length of a beam for a particular joist span. For example, the table will be called something like “deck beam spans”. This is confusing because it is not only telling you the beam span but also telling you maximum distances you can space your deck support posts.
What is a 2 ply deck?
You are limited to two-ply beams – that means two pieces of lumber, such as two 2x8s nailed together for use as a deck support beam. When using a two-ply deck beam atop 4x4s, you are limited in terms of how far you can space your deck support posts.
How long can a 2x12 beam span?
Because the maximum span a two-ply 2×12 can run is just over 9’. The maximum span indicates how long a beam can run supported by two deck support posts. A three-ply 2×12 would allow you to use only two deck support posts for the 10×10 deck. A beam of that size can span nearly 12’ while supporting 10’ joists.
How high can you build a deck?
As mentioned above, code will also inform you how high you are allowed to build a deck using 4×4 support posts, which is usually never above 5’ from the footing to the deck surface.
Do you need a deck to fit a circular pool?
For instance, if you want to build a deck to fit your circular, above-ground swimming pool, then you are going to need a number of posts to fit the curve of the pool. However, you can still orient your joists to ensure the fewest amount of deck posts are required.
