# Deck screws how many per board per joist



## MHW

Do I really need 2 screws per joist on my deck boards rather than doing 2 screws for one joist and then one on the next joist? 10 ft p/t boards on 16" joists.


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## crank49

Two screws to prevent cupping of deck boards.


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## dday

> Two screws to prevent cupping of deck boards.
> 
> - crank49


this


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## JCamp

2 is fine as long as its a 6inch wide board. I have, and have known ppl, that swear by using 3 screws in a 6in wide board. Slightly over kill but they will not move


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## johnstoneb

You don't say how wide. 4" 1 screw alternating side would work. 6" you need 2 per joist.


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## LiveEdge

If you are going to go through the work of doing your own deck, pay the extra $10 in screws and do the extra time to put the additional screws in. It's not the place to try to cut corners.


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## DrDirt

Depends - There are also hidden fastners which is what I did with my decking… where there is a biscuit made out of plastic with a built in spacer, so that you would hold the board by its edges

https://www.mcfeelys.com/screw-fastener-web-store/deck-clips-deck-plugs/live-cylinder-eb-tys-with-screws-100-pk.html

Then I use two screws per board on the joist at each end.

For direct screw down… the screws hold the board in place, and prevent cupping, thus 2 is standard.


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## OldCoach

Not to change the subject, but I built a deck 16 years ago using deck screws, the green ones. Never have I been so disappointed in a product. I cannot tell you how many screws failed due to rust and decay. I used two per joist on 6" wide boards by the way.

Last fall I removed this deck and replaced it with concrete. I would estimate that 90% of these deck screws were decayed to the point where they were no longer doing the job they were designed for. Plus the fact that now I have all this deck wood that I have to spend so much time just trying to get pieces of screws out in order to reuse for planter boxes or any other projects I want to use it for. I used 35 pounds of screws to build this deck. After demo, I have less than 5 lbs of screws that are not decayed that I can reuse on these other projects.

If I had to do it all over, I would use nails. Just my experience.


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## matthww

Built about 20 decks start to finish with a crew, and we always used 2 screws on wood decks, (torx head outdoor screws, predrilled with an 1/8" pilot hole) UNLESS we were using composite decking boards with hidden fasteners. Hidden fasteners required 1 screw per joist, but these boards were not prone to cupping.


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## rwe2156

Countersink/predrilling make for a professional job. This is especially critical on butt ends.

And don't over screw the screws even counter sinking this can result in splitting.

I think sanding and using a stain/sealer really makes it a good job, even with PT wood.

I've built quite a few decks and I really think 12D stainless steel ring shank nails are worth considering.


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## ArtMann

All I want to say is that I have built several decks and I agree 100% with rwe2156. Ring shank nails are great but I would shoot them with a pneumatic nail gun. I am too lazy to hammer them in.


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