Deck Resurfacing

[Buckaroo5]

I am working on a 28 year old deck. Tore off all the wood decking and installing Trex. Their is some variability in the height of the joists - 1/4" over 16" so I don't think that is too bad. I am installing some new joists (2x8's resting on 2x8 cross members supported by 4x4's) as my design includes some breaker boards. There is a little bowing on the new lumber but I have pulled it down with clamps and there is still elevation difference of 0- 1/4" for two joists within 6" along the 12' joist - seems like a lot and I think it would be noticeable. Perhaps this is due to shrinkage on the old joists. I could get it closer with my DeWalt planer but am concerned about what happens when new lumber shrinks. What do you guys think?

 

[65ranchero]

I know for sure that PT decking will shrink up to 1/4" or more after it sits for a year installed.

 

[mm08822]

Can you double up 2 of them with opposing crowns, and then clamp them flush to each other and nail both together while clamped? Then secure ends.

This should keep them both closer to straight between end points and being doubled up would also eliminate some bounce.

Don't forget the tape.

 

[Skiff Builder]

What is the height of deck off the ground?
Reason I ask is at 5' elevation, wavy decking is very noticeable to an eye of someone standing on the ground.
At 10' elevation it's only noticeable when on stairs , if attached to side of deck.

Try to eliminate at least half the variation by sorting through joist sizes before placing them or using your planer, let the air drying take care of the rest of the variation.

 

[larry4406]

At the day job, the excellent framer crown side up and then slides an 8’ level across deck joists and power plains them flat.

The lesser framer eyeballs crown only and calls it quits.

Oddly we do not apply flashing tape to top of PT joists before decking.

 

[Buckaroo5]

At the day job, the excellent framer crown side up and then slides an 8’ level across deck joists and power plains them flat.

The lesser framer eyeballs crown only and calls it quits.

Oddly we do not apply flashing tape to top of PT joists before decking.

This is what I was thinking

 

[Buckaroo5]

What is the height of deck off the ground?
Reason I ask is at 5' elevation, wavy decking is very noticeable to an eye of someone standing on the ground.
At 10' elevation it's only noticeable when on stairs , if attached to side of deck.

Try to eliminate at least half the variation by sorting through joist sizes before placing them or using your planer, let the air drying take care of the rest of the variation.

it's only 22" off the ground. I think I will do the planing.

 

[Buckaroo5]

I know for sure that PT decking will shrink up to 1/4" or more after it sits for a year installed.

This doesn't surprise me but what do when you are throwing in a few new joists?

 

[Skiff Builder]

When I build a new deck, I sort the joists by actual width in 1/8" increments. Say, 9, 9-1/8, 9-1/4, etc. I than lay those joists starting from narrowest to widest. In essence the deck may slope as much as 1/2" from right to left but it is at least in plane and not really noticeable.

 

[wssix99]

I had this same problem with the same material. I built my deck just over 10 years ago. It looks OK, but I still regret not leveling off the top of the joists. The install was a ***** and water pools on the deck.

 

[jack stand]

I am working on a 28 year old deck. Tore off all the wood decking and installing Trex. Their is some variability in the height of the joists - 1/4" over 16" so I don't think that is too bad. I am installing some new joists (2x8's resting on 2x8 cross members supported by 4x4's) as my design includes some breaker boards. There is a little bowing on the new lumber but I have pulled it down with clamps and there is still elevation difference of 0- 1/4" for two joists within 6" along the 12' joist - seems like a lot and I think it would be noticeable. Perhaps this is due to shrinkage on the old joists. I could get it closer with my DeWalt planer but am concerned about what happens when new lumber shrinks. What do you guys think?

Today's "dimensional" lumber seems to be more of a rough approximation of said dimensions anymore.
Thankfully it so cheap to buy!
PT seems even worse.

 

[CraigStu]

But if you plane the wood don't you remove the treating?

 

[manwithtools]

But if you plane the wood don't you remove the treating?

No, not if it's SYP found east of the Rockies. That treated wood is "pressure" treated and the treatment fully penetrates the wood.

 

[jack stand]

^^^ not true beyond about 1- 1 1/2 inches. I've never cut a 4x4 (3.5x3.5) that didn't have a 1"+ white wood un treated circle in the middle.

 

[manwithtools]

not true beyond about 1- 1 1/2 inches.

And how thick is framing lumber?

BTW, I've cut plenty of 4 x 4's that were fully treated. The center is the heartwood of the tree and will have a different appearance even if the treatment penetrated it.

 

[Shiftless]

When I tore off the old redwood 2x6s, I installed new framing with 12 inch centers to better support the new Moisture Shield synthetic deck boards.
A neighbor installed Trex over 24 inch spaced joists and it looks like a roller coaster.

here is what Google told me about Trex…

Pro-Tips for the Best Results

• Consider 12-inch OC for standard decks: While 16-inch spacing meets the basic minimum requirements, many professional deck builders recommend reducing to 12-inch OC even on straight decks. This yields a much more rigid, premium feel and prevents bowing in hot, direct sunlight. [1, 2]
• Picture Framing & Blocking: If you plan to "picture frame" the perimeter of the deck, or if you are doing complex board patterns, you will need to install extra framing/blocking underneath so that every board end has a joist to secure