No problem, install cup down. That board was most likely on top of the stack as it sat in the lumberyard and the top dried out more than the rest of the boards. Since you are seasoning the Ipe for a month, the wood will be drier than if you installed it right away. The wood will continue to dry out after installation, especially in the sun. All the boards will cup (just slightly) as the wood dries out quickly, but the decking will flatten out as it reaches a stable moisture content. So don't panic. The wood may not look so great as it is drying out. It will show considerable surface checking (small cracks) and some minor cupping during the first season as the hot sun dries out one side. The surface checking is how the wood breathes. The cracks close up and the cupping flattens out (if the decking is installed correctly) once the wood reaches a stable moisture content. So keep these properties in mind as you design & install the deck. The boards have to be able to reach the stable moisture content. That is why cross ventilation is essential. Both sides need to dry out. The decking needs to be screwed very securely to the joist and a little adhesive will help keep the board flat. After a couple of seasons the boards will not want to cup anymoore, so by the time the adhesive wears out it has done its job.

Thanks for the response Aidan. I feel much better now, as I've been worried sick about my Ipe just sitting there waiting until it can be installed. I had it delivered beforehand fearing that I wouldn't be able to get it locally when the time came to start the deck.

Can you answer one other question? I'm planning on plugging with a forstner bit. How far ahead can I go before I circle back and put the plugs in? One board at a time? Several? A day's worth?

thanks,
Kim

A forstner bit. Any reason you'd choose that over a countersink bit?

Just finished my Massarenduba (Brazilian Redwood)deck last year. You'll need to use a carbide bit as the wood is so dense it will dull a regular bit. Same goes for saw blades.

Good luck and have fun.

From what I've read the forstner leaves a much cleaner hole. I have purchased the forstner bit (carbide tipped)and have to agree. Did you plug your Massarenduba? Any advice?
Kim

Are you planning on predrilling the screw holes? I'd certainly recommend it, otherwise you'll run the chance of splitting the wood. If you use the forstner it will double your work per hole, as you would need to drill a second time with an 1/8" bit before inserting the screw.

I would advise to use SS screws for the best results.

Yep, I plugged the deck. I bought a plug cutter bit and made my own plugs from the scrap deck boards. I had originally bought pre-cut IPE plugs but there was a substantial color difference that would have really highlighted the plug holes.

Just remember, take your time and enjoy the process.

Thanks Trublue55.
Yes, I do plan on pre-drilling the screw holes, and I do plan on using stainless. I just haven't decided on which. I'm leaning towards a Promax screw from McFeely's.
I don't have a drill press, so I'm going the pre-made route for the plugs. I ordered a small package to mess around with before making the plug/no plug decision, and the plugs surprisingly match pretty well. Who knows if that will be another story when I order the full amount that I will need.

How far ahead did you go before you circled back to plug your holes? I can't seem to get a response to that question.

Thanks,
Kim

No need for a drill press to make plugs. Just clamp the wood down and start drilling. The plug cutter finds a center. Remember the end you see will go into the hole, so it need not be perfect. When I make plugs in the field, I clamp the wood to the truck bed rail and drill horizontally into the end grain (much easier than trying to hold the drill like a drill press). Release plugs with saw; repeat. Ipe is tough enough to make plugs from the flat grain, which will blend perfectly with the deck, but you need to rip the board on the tablesaw to release the plugs. Remember to line up the grain of the plug with the grain of the wood before tapping it in. I use a small japanese pullsaw to cut the plug flush. Sand with 60 grit orbital sander to finish Ipe. You should plug soon after screwing before the holes get nicked around the edges or fill with debris.