Pressure Treated what to do about cupping etc

[PaddyO]

Hello,
Perhaps this is not the correct forum for this but here goes.I subbed out the framing of a 400sf deck ordered the materials,and made the mistake if leaving the job unsupervised.The materials were delivered (2x10 Pt,6x6 posts) and the framer who I have used on a few occasions (with good results) went to work.
Bottom line is when I returned ten days after the framing jobs completed I noticed a few issues.
1 Some of the double and triple joists were chiselled away so they could all sit on the hangers uniformly.
2 Where the doubles and triples made contact with the tops of the posts there were PT shims in place because again the 2x10 were not making proper contact with the post.

The framer told me that there was such a difference in the depth of the material from 9 1/4" to 9 1/2"(which I verified) that this was the only way he could make it work.Now the Pt has begun to cup and the outer rim has almost pulled away from the structure.Client is flipping out.
The framer has laid the blame on the poor quality of the PT and the supplier is saying nothing except this is to be expected with PT.Can anyone point me in the direction that can get the issue resolved.
I have a tendency to side with the framer but I could be wrong,but i think also the material if it was such junk should not have been used in the first place.

[davenorthup]

Re: Pressure Treated what to do about cupping etc

When building decks I use beams instead of 2x or 3x built up beams.

For deck joists we have to order 150% of what we need. We measure the heights and use all the same sized ones. we generally use 2x8 and usually measure 7 1/8" - 7 1/2".

Sounds like your framer did not take the proper care in selecting the materials. I bet the deck joists are worst if he did not plane them.

PT wood out west has been like this since I ever first touched a piece of it.

[jimAKAblue]

Re: Pressure Treated what to do about cupping etc

Isn't being caught in the middle of this no win situation great?

While the framer could not possibly know which members would warp, twist, cup, etc excessively, he could have constructed everything with the worst case scenario in mind. Often, if you lock in items like the rim with enough fasteners (and technique) it can minimize the drying out effects. Sometimes, it's impossible though.

Have fun replacing the bad parts under your warranty clause.

The lessons learned will last you a lifeti...er...a few weeks.

[Happy Home]

Re: Pressure Treated what to do about cupping etc

You are the quality control dept. We all know pt has its problems. I'd look at the stock in the yard to see how its running. I still would be at the job and cull through the delivery and remove what is not suitable to you and get replacements in the first day or so.

We talk here about not being responsible for owner provided material, inspect, etc. You're framing sub assumed you knew what you were doing. He has 2 - 3 guys to work.

I think its difficult to put it all on the sub for various reasons. This would not be the first load to go back to the yard. This is why I charge 1 day to load the job.

Got the Tools of the Trade mag email a few days ago. Greg Di has part of an article about steel framing in it. Something to think about ?

http://toolsofthetrade.net/

[dlhunter]

Re: Pressure Treated what to do about cupping etc

I have worked with PT 2x10's enough to know there is about a 10% chance of them all measuring 9 1/4". I always toe nail the joists to ledger and hanger afterwards so it isnt an issue. Just curious, what is cupping? The decking material? Do you have good ventilation underneath?

[tomthetoolman40]

Re: Pressure Treated what to do about cupping etc

Did you supply enough material that the framer could have culled better pieces, or only enough to do the job and he had to use every piece that was delivered? Also could he have called you, or were you unavailable for the ten days?

PT always varies in size and usability. I also use beams instead of build-ups.

[PaddyO]

Re: Pressure Treated what to do about cupping etc

More Than enough about 30-40% more than required.Was out of the country for the ten days(not something I could have avoided unfortunately).What I mean by cupping is that the outer rim has cupped away from the ends of the joists.
To be honest about it I should have held the job up till I got back but it would have screwed up the project timeline.Man I got to tell ya I'm done with PT,too unpredictable,a potential headache I could do without.Lesson learned.

[jimAKAblue]

Re: Pressure Treated what to do about cupping etc

Paddy, it sounds like you had sufficient material to get the job done. There's a good chance that the framer didn't understand which members would be best for the rim. Typically, the clearest pieces come from the center of the tree. They look pretty but are more prone to cupping. To combat that, the framer should either select the others (have more knots) or combine them with the cupping side opposing one another. Of course, they don't usually do that because it's much easier to spoon them and get them nailed tight.

It sounds like you have this lesson down...now, onto the next disaste...er lesson!

[NW Architect]

Re: Pressure Treated what to do about cupping etc

KDAT - worth the extra material cost

[PaddyO]

Re: Pressure Treated what to do about cupping etc

NW Architect,
You know its next to impossible to get KDAT in Boston and its 250% the price of the regular PT.Special order from lumber supplier,its nuts.And is there any guarantee it wont go to shyte after installation?

[Happy Home]

Re: Pressure Treated what to do about cupping etc

Some interesting const details on resi steel decks.

http://www.deckmagazine.com/article/363.html

Here's the guys website.

http://www.cdfcontracting.com/

[dlhunter]

Re: Pressure Treated what to do about cupping etc

I'm curious if anyone has been using steel framed decks. I was going to look into it but it just seemed like cost and availability would be issues. Also had some concerns about the longevity of the new products geared towards residential decks.

[Deansocial]

Re: Pressure Treated what to do about cupping etc

I was curious about steel for decking but not really found anything in the uk

[Dick Hackbarth]

Re: Pressure Treated what to do about cupping etc

PaddyO:
If everything else is o.k., or at least can be lived with, I’d use some through bolts or some of the newer structural screws from both sides, to gradually (over several months) pull the 2x’s back together. This will also make them act better, more like one integral beam member. This will take a little thought for the proper location and spacings, edge and end distances, etc. When I use multiple 2x’s for a built up beam, or any exterior beam for that matter, I like to cap the beam with some peel-n-stick or ice and water guard to keep the water off the top and out from btwn., where it never dries. Let this cap hang over .5" on each side to shed water, then install the decking. The decking only has to be nailed/screwed to one 2x, so I would prefer to have my member edges line up at the beam bearing locations, at the max. bearing loads and stresses, rather than the top. You should cut post notches separately for each 2x if widths vary much. Also, the uniform top doesn’t matter for hanging other joists, just match to top most edge of the beam. If the members are properly joined together they will act as an integral beam, and provide proper bearing at all the right places. I agree with NWA that you can get kiln dried PT material, but it is more expensive, for the extra cycle of processing. Alternatively, get this lumber early and sticker it, and weight it down, and let it air dry for a few weeks, that helps too. I’ve seen this stuff come out of the lumber yard so wet it would splash in your face if you hit it with a hammer.

[NW Architect]

Re: Pressure Treated what to do about cupping etc

#10 PaddyO I guess we are spoiled out here where the tall trees grow. Don't know what the markup is on KDAT, but it must not be too bad since its use is not uncommon. It DOES make a difference in the long run, because whatever movement is going to happen HAS happened, before installation, so you can manage things as you build and know what the result will be.