Deckboards buckling after 1 year!?

[tom_matthews]

I'm logging on and asking this question for a co-worker. She wants help fixing her deck. Here's what she says:

"Last year, I had a new deck built at my townhouse. About two months after construction I coated the wood with a BEHR waterproofer. I thought followed the instructions on the can. A little over a year later, and the wood is buckling on the deck surface and handrails. I asked the deck-builder to take a look at it, and he told me I must have put the stain on wrong. I'm not sure what to think.

Any idea on what the problem is, how to fix it, and how to prevent it from happening again?"

[Java_Bob]

sounds like cheap/non pressure treated lumber, what was in the bid for the job??

[cirino.ed]

pressure treated wood is usually very wet when it is purchased. I've learned it is a good idea to let the deck age for several months to let the wood dry completly. When the wood is dry it will let the new treatment absorb.
nailing decking down often allows it to buckle as the wood dries. using screws helps keep decking where it belongs.
wood has a natural cup to it. on the end of the board look at the rings. the board should be laid so that the rings are convex or an upside down cup. this will allow water to run off the decking instead of getting trapped in a cup as the wood dries
good luck

[pushkins]

What cirino.ed said in the previous post about "cupping" is correct most good deck builders will be careful of the grain of the wood to lay it cup side down. Decks should also always be screwed down NOT nailed as the wood dries the nails always have a tendency to pull out allowing the wood to buckle ( I saw a deck yesterday that over a space of 24" the deck board has buckled upward 8").

Is the deck treated lumber?, Java_bob has a great point about the type of material and the quality, I always tell this to everyone.....There is cheap wood and there is good wood, usually the job price is a good place to start with quality comparisons.

As for fixing it, have the deck and handrails screwed down if it is not already, (I doubt it is if it is buckling so badly). Have any very bad pieces of deck and handrail replaced, have the deck power washed down and after it has dried ( couple of good drying days) re coat the deck with a good quality sealer.

I like Cabot's (not cause it comes from where I once came from ) but because I have had very good success with their products over a long time span. Most of the upper end sealers are pretty good.
Sealers are like paint, you get whet you pay for.