QA

What Is A Deck Joist

A decking joist is a repeated board used as the structural base for your deck frame that is attached to the ledger via galvanized joist hangers. Typically, joists run perpendicular to the house, while the decking on top runs parallel to the house.

How far apart are joists on a deck?

Step 4: Make Sure Your Joists Are Spaced Correctly Deck joist spacing should never exceed 16″ on center (with the exception of MAX deck boards, which allow for maximum 24″ on center). For a more rigid feel, 12″ or less may be preferred.

Can I use 2×6 for deck joists?

2×6 joists should only be used on ground-level decks that do not require, and will not provide for, any guards. Most decks use 16″ on center spacing for joists. Most decking is not strong enough to support longer spans than 16″.

How many joists do I need for a 12×12 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 I use 4×2 for decking joists?

4 x 2 Timber Rail / Joist These decking joists are the most common sized framing timber for decking. They provide a solid structure for fixing your decking boards too. When making your decking frame you should use a 400mm spacing between your timber joists.

Do deck joists need to be pressure treated?

Do Deck Joists Need to Be Treated? Pressure-treated lumber is ideal for deck framing. We also recommend using joist tape or a wood protectant to help shield cut ends from moisture damage.

Should deck joists be 2×6 or 2×8?

That’s a model deck code which includes joist span tables. If there is to be a railing, you need the joists to be at least 2x8s. 2x6s don’t have the depth needed to resist the leverage that can be placed on a railing post bolted to them.

Can I use 2×8 for deck joists?

2×8 for joists will be fine, with 16″ OC. Should use 2×10 for beams but 2×8 will be fine as well. If you are worried you can triple the 2×8 for the beams but double will be sufficient. You should put the beams at 7 and 14 feet out from the house, with the piers you should do 3 per beam with spacing of 1, 7, 13.

Can I use 2×8 for deck boards?

Q: Can I use 2×8 treated lumber as deck boards? A: No, that’s a not a good idea. Lumber wider than 6 inches should not be used as a flat surface. Wide, flat boards have a tendency to pool rain water, which can lead to cupping problems.

How many Trex boards do I need for a 12×12 deck?

(Choose from 8, 12, 16, or 20 ft board lengths. Choose which board best fits the dimensions of the deck.Decking Materials. Board length Boards required 8 FT 206 12 FT 137 16 FT 103 20 FT 83.

Can you use 4×4 for deck joists?

For most decks, 4×4 lumber is strong enough for structural posts. If a deck is raised more than 6 feet above the ground, codes may require 6×6 posts.

Should I replace my deck joists?

Joists are hard to replace without tearing up a portion of your deck, so if they show damage, it’s probably time to replace and rebuild. Also, damaged joists can be the result of more than just age.

How much does it cost to replace a deck joist?

(see minimum charge section below): Joist replacement $185.00 – $285.00 (per) Decking replacement $12.00 – $15.00 per LF or approx $30.00 per SF Stringer replacement $245.00 – $375.00 per stringer Footing installation $325.00 – $475.00 per footing Basic staining of deck/rail $5.00 – $6.50 per square foot of deck.

How do you fix a rotted deck joist?

A: The easiest way is to repair a joist is to install a sister joist to strengthen the damaged area. Use a hammer and chisel to chip away the damaged wood. Liberally apply two coats of waterproof sealer over the damaged joist. Cut a reinforcing sister joist from lumber that is the same dimension as the damaged joist.

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.

Is 4×2 strong enough for decking?

2×4 Deck Joist Can Only Span 5’8″ (1.72m) Between Supports. Either you are limited to a small deck, less than 6′ (1.8m), or you will need a mid-span beam. Three 6×6 posts, one on each end plus at mid-span, allow you to use 2×4 joists but is still strong enough to not flex with every step.

Can you use 3×2 for decking base?

3×2 can be used but you’ll have to support it more frequently throughout its length, say every five feet or so.

How long do decking joists last?

With the right materials and good design and installation practices it is possible to design a timber deck to have extremely long service lives but 15 years is the industry norm. TDCA advises that you ask for written evidence to support the durability claims and standard of the timber you buy.

How long do treated deck joists last?

Whether for framing only or the decking too, pressure treated lumber lasts a long time. Pressure treated lumber exposed to freeze-thaw and wet-dry cycles without care or maintenance will last about 9-years. With proper maintenance and treatment, the same deck will last 40 plus years.

Can I use untreated wood for deck joists?

Yes, you can use untreated wood to build a deck, but not without preparing it first. You can’t, of course, pressure treat it yourself, but you will need to seal; the wood and stain/paint it to ensure the wood is ready to take on the harsh external weather.