Some deck questions...

[Innovate1]

Talking to some contractors about deck replacement. One said they used cedar posts rather than treated posts as the treated posts can bow. I know the posts often have knots and grain that may cause bowing but all the 6 x 6 posts on the current deck still look straight. Said something about cedar beams also but thinking cedar isn't nearly as strong as treated lumber. Strength is more of an issue for beams than posts. Also mentioned they could paint the frame before the deck went on. I have seen this done in joist space in unfinished basements but never on decks. I question how well the paint will stick to treated lumber. Wanted to get some feedback here on both items. TIA.

 

[Old tool guy]

Ask them to give a quote for steel posts.

 

[matt_i]

I think cedar is a dodge for posts. What I would buy is UC4B aka Critical Structural posts. Use the peel + stick to exclude moisture from the horizontal pieces.

I also drew up a design to use reinforced concrete posts with a shimmable bolted saddle at the top, but you have to get very close on your elevations.

 

[steves_001]

Use green treated. It will grey up in a few years anyway same as cedar. Structural cedar is big money too.

 

[PCustoms]

PT is a tossup

I've bought pieces that should have twisted (based on grain/growth rings) stay dead straight and stuff that should have been fine twist.

I used over 10 6x6x10 and 4 4x4x8 on my deck 3 years ago and nothing went crazy. The 6x got some checking but that's all.

The 5/4 went noodly in a few spots and the 2x6 cap looks like **** with raised grain in more spots then not, plus one has a weird wave to it that I probably should replace

 

[couch67]

I'd stick with PT framing for a basic deck. The understructure doenst need paint - Is it going to be visible, and that is why they suggested?

Make sure it has good ventilation underneath, that is key for it to last. I like using deck tape on top of the joists.

 

[jar944]

Get treated clear (as possible), centered heart 6x6s and they shouldn't bow. You might (will) be picking through the pile to get them

 

[Rusted Nut]

Cedar is very seldomly used as structural lumber. Fence posts yes, deck post or beams probably not. Ask contractor to show the span tables in the building code that allows this.

 

[Burt Shaver]

The few decks I have built I have used PT, green PT is not available here anymore so it was the brown PT, forget what it’s called. I used synthetic roofing underlayment to cover the tops of the beams and joists. I seen someone mention deck tape for the tops of the joists here, that might be easier than the synthetic I used but the idea is the same, don’t wrap the entire joist or beam, just keep the water from laying on it and the frame should last many years.

 

[YeCats]

How old are you and/or how long do you plan to stay at this house?

At 65, I built my deck with PT. Figed it would outlast me.

 

[mikedodge]

I haven't seen PT posts bow but maybe that's a regional thing depending on where they are from or how long they need to be?
It usually comes down to cost, they both have similar life span.

 

[Viper98912]

I've seen cedar for fences, playsets, and decorative pergolas, but never for a deck structure. But, I'm not a deck expert and don't do it for a living. But I did build my own deck from 6x6 PT and I did stay at a Holiday Inn once.