I guess I don't have to tell you the reason...the wood wanted to cup and the clips just sat there and watched. Pull the boards, flip them, and face screw into the joists.

or, you could rent a sander. sand it flat, and then face screw.

steve

O Man,,I am really sturgling here...OOO the preasure,,,OK Im good I am not going to go into a rant about those stupid clips or wonder why they are still being sold.Halper my Man there is no fixen those clips I agree with the Steve Mon on what you can do now,you might get away with face fastining what you have but be carefull dont try to take all the cup out just snug the ss screws down with a slight countersink and mabey use a 5'' orbital with 60 grit and just take out the high places.Sorry Man I know it was a lot of work to put the stuff down that way you have joined a long list of clip using folks who have the same problems. John

John,
I'm sorry to hear that you are sturgling. Hope you recover soon :-)
you're right though...my plan B was a bad idea. you face screw severely cupped boards, they can split down the middle and end up being expensive firewood.

I still think that renting a floor sander and flattening out the deck might work. then he wouldn't have to do anything else...maybe.

steve

Well, it looks like I have a bit of work to do.

Assuming I don't go out and rent a floor sander, which I might end up doing, what are the pros and cons of orbital vs. belt sanders for this kind of job? I have a 1/4 sheet pad sander, but my hand goes numb after a minute or so of using it. Are the 5" random orbital sanders any easier on the hand and arm? A belt sander wouldn't have the vibration problem, but they're quite a bit more expensive and might be overkill for a 17'x15' deck.

Your advice?

The belt sander is defffently out that tool would cause a lot more problems.The floor sander would be really hard to control on an uneven surface like your talking about, its hard to control at all, and it wouldent get close to your hadrail if you have any.The makita 5'' orbital has the least vibration of any I have tried but after using one for a while you will feel the effect, there are gell gloves that are made for that, daluthtrading.com still sells them I think but you can probley get them local. Anyway I still vote for the orbital and dont try to take out all of it,just hit the high points. The BRW will coutinue to move around until you fasten it to the frame so you better do something kinda quick. John

Thanks guys for your answers. I've been up playing by Lake Tahoe for the last week and didn't have a chance to get back to you...

I'm going to go with the orbital sander. I really didn't have anything else to do for the rest of the summer!

After sanding it flat, I'll gingerly face screw it. Another question...If I use the small headed screws, won't they pull through the hole when winter comes and the boards try to cup again? Or doesn't that happen in practice? I have a couple hundred of regular 2.5" SS FH screws, which would eliminate that problem, but I think I'll be ready for a straight jacket after drilling & plugging that many holes.

I dont use the flat head srews at all,the square drive trim head ss screws have really wide threads,its the threads that keep the fasteners in not the head.Use a 1/8'' bit for the predrill and the counter sink,its possible to use a 5/32'' bit but be carefull not to pre drill into the frame just the ipe.Dont try to sand the whole thing flat just take out the high spots. J

The straightjacket loosened up and I can finally reach my keyboard again...I thought I'd give you guys an update...

After the sanding dust got to me, I pulled out my Stanley jack plane from the garage. It only took a couple of hours (days?) to knock the ridges down and make the deck roughly flat. At that point, I hired one of the guys who stand in front of our local Home Depot to finish the sanding...80 followed by 120 grit. Asthma and sanding just don't mix, even with a mask and a shop-vac hooked up to the sander.

This weekend, I'm top screwing using the trim head screws. I'd like to set them deep enough to fill the hole with a plug, but I'm not sure how far below the surface that should be. 1/4"? 3/8"? Or should I just forget about it and leave the screws exposed??

That planer was a good idea BH,pluging the holes is a different go around involving a forester bit, pre made plugs, and sanding the whole thing down again.It is possible to use the same drill bit for the counter sink and the pilot hole by routing out the very top of the hole with a little swerel and trewel thing, you will only need 3/16'' or so. Then when you put the finish on you flood these holes and they all but disapear. As a given this is not the look you were going after but its not bad. Hang in there ol Son. J

Just a little caveat. If you are planning on sealing the deck, 120 grit paper is too fine. 80 would be the absolute highest I would go.

Can any of you pros provide CLOSE-UP pictures of your face nailed decks (multiple shots please). I used the clips, and have slight cupping, but another Ipe deck I have seen that was face screwed also has cupped, really badly. I don't think with the 3/4 you can really stop it by just facing screwing it.

Provide multiple pics to prove me wrong. Thanks!

Nuts,,there are a lot of reasons for ipe to cup, could be the frame, could be the material came from a low baller,could be no cross ventalation, might be the project needed counstruction adhesive,things like that. Bottom line>>> the clips cause more problems and take a lot more $ and dont really fasten the decking to the frame. I dont nail ipe so cant help you on that one. We do face fasten ipe with ss screws, use con adhe on the joist and I have never had a call back for cuping there are a few of those projects on my site but as far as proving anything,thats not my job far as you go,if you wanta go the clips use em. J

Nuts,

I respect that you have your opinions on certain issues but what you ask is a little unreasonable. Some of us have spent a few years on this website volunteering our time to help savvy DIY'ers get their project complete. My email baskets are filled with 3-5 email requests per day seeking advice. If I am qualified to offer the help, I spend time answering every one with detailed instructions in addition to coming here and offering the same. I find it a little petty that someone would ask me (or John or any professional) to spend a whole day going to projects and snapping multi angle pictures so we can debate procedure with a knowelegable, but still inexperienced, homeowner.

I have made many friends here and many of these friends have become my customers. I am certain any one of them will attest to my advice being sound and that I do my best to offer above and beyond customer service. I have built a total of maybe 15 decks in my lifetime so for the most part I leave tech questions to Brooklyn, John Hyat, or Al as they have much more experience in that arena. You have built one deck and its completion is recent. Is this correct? With all due respect I have to ask you outright how this qualifies you to give advice. I am not trying to be mean and I ask the question with respect to your passion for learning and understanding wood work. Please don't take my post the wrong way, but I'd like you to reassess the gauntlet you have bravely thrown down. What is it you hope to accomplish?

You both need to calm down. I try not to type huge posts, so my quick phrase of "prove me wrong" has been misinterpreted completely. I never asked either one of you to spend a day snapping pictures, and would only expect that if I were paying you to do my deck. What I am asking (which I figured was easy enough in some free time, which I know most of us have little of) is to take two or three shots of your own deck (I am sorry, but I cannot remember which one of you has the deck in your own back yard). I want some close-up shots of the boards and face screws. Not a standing-back shot of the whole deck. I have seen many pics from you guys of your work, and i know that it is all quality. I just have never been able to see the close up shots, like I would be able to physically look closely as if I were there. I am purely trying to do this to compare it to my own results on my project. That's all. You both seem to think I am trying to rebunk your time proven results and efforts, and that is completely wrong. I am sorry that you guys felt I was attacking you, but I wasn't. Nobody around me here knows what they are doing with Ipe (the local lumber yards guys cannot even pronounce the word properly...what does that tell you!?!). One deck I looked at, they guy used a nail gun to put it down!!!

I want to see if the results I got from the clips are bad, liveable, or if I will need to (god I hope not) sand like some others here have decided on. I just did not want the look of the face-screws, and plugging the entire deck was not an option I liked either. I did use plugs, and liked the look, but at every joist would have been a nightmare of work.

way out question.. but the boards you saw cupping.. did the guy use 2 screws, per joist.. Spaced evenly apart? If you put 1 screw, or 2 screws mostly in the center, you're leaving an opportunity for the board to curl like a book page.
Also, pre-drilling is important and the bit has to be correctly sized and just through the ipe. The screw should be put in moderate speed so as not to strip or barely grab... Again, another way a board can just curl up without any resistance. Also, was it ipe or a board that looked like ipe... maybe Philippine Mahogany, that has a variety of dark red which looks like ipe.

gorilla... I do not recall to be honest. I know there were two screw per joist, but as to the location, I don't know. I would assume that most would be to the outside, but since they were cupping, it could have been a less-than-perfect install? I am sure it was Ipe too.

My project has a small area (a 12 x 14 deck area) with about 25 or so 14' boards. Out of those 25 or so, I would say four are cupping. Not badly, but enough that I notice. I know I was careful with my install, but I used clips, not face screws (except on end boards). The one Ipe deck that is nailed is a nightmare. Nail pop-ups, cupping, everything you can imagine. Horrible workmanship. It was a nail-gun job too. I don't know how they got the gun to do it, but they did. It looks like sh*t!
I am just curious if my slight cupping is bad (and may get worse in time) or if it is the "norm" somethimes. That is why I was looking for pictures. Just so I can compare. Cheers.

Nuts,
Nails won't ever stop wood from cupping...clips won't either.
I face screw with 2 screws at each joist. I usually plug, so I use #10 2.5" bugle head screws. If I don't plug, I use #8 2.5" brown headcote SS trimhead screws. When you buy wood that has been stored inside, and lay it down horizontally in the sun/rain/snow, it's gonna want to cup and move. My job is to make sure that it won't...and face screwing is the best way to accomplish that.

steve

"If a board is going to cup-it will."
Boards that have propensity to cup usually do so for a variety of reasons, none of which have to do with the fastening systems. No fastening system can prevent, delay, or otherwise stop a board from cupping except over the joists- by virtue of the fact that the cupping occurs between the joists.
The main reason boards cup is from moisture, either within the board or the immediate surroundings. Ventilation of the deck is a key factor. If the deck is low to the ground and the ground does not drain fast enough, the evaporating moisture rises and is trapped underneath the deck.
When the bottoms of the boards, especially hardwoods, dry more slowly than the top of the board which has free air flow and sunlight, the boards will cup. Hardwoods need to be fully seasoned before building the deck per the suppliers web site notes. (fine print)
The best prevention is to allow ventilation by spreading a healthy layer of coarse gravel or other material that allows the rain water to soak through and then dry. Skirting the lower sections of the deck also enables moisture to be trapped under the deck. Tops dry, bottoms don't= Cupping. Well ventilated + seasoned board= less oppotunity. But, if a board is going to cup- it will. All you should do is design the project to diminish the opportunities.

Boards which are dimensional unstable, 3/4" x 5 1/2", IPE for instance, are more like to cup and more severely. Massaraduba, too, has the characteristics of absorbing moisture and expanding in such direction and strength to shear 10 ga. wire screws. When the deck fasteners fail due to the abnormal movement from moisture absorbtion, nails pull up, screws shear and it's "decks gone wild!". Design and execute your project to avoid expensive and labor intensive repairs.

see you're new to the site Jim, welcome aboard.

X 2 from me Jim. Design and execute sounds good to me. J

Execute is the right word.

REMEMBER: FACE SCREW, PLUG, THEN SAND! FACE SCREW, PLUG, THEN SAND!

Sanding, then screwing doesn't exactly result in a flat deck :>(

Oh well, back to sanding...

Deck Master Jim - nice post. Jim, John, Pressure, et al,

My framing is down, low deck 18" - 24" Im in so Cal. Below my framing is .4 mil landscape film (plastic) covered by 3/8 - 3/4 gravel. Below that is soil. Is the plastic helping or hurting me? It will prevent upward moisture during dry times (most of the time), but will it be a problem during rain? Should I remove the plastic and and just go with gravel over soil? I won't have a problem with good cross-ventilation, I don't need to skirt, or can vent it well.

Erik

Remove the plastic. John

Thank you Sir, If I may, my other pressing issue is wether to user 1X6 or 1X4. Is 1X4 much safer in regards to the possibility of cupping/warping?

Erik

Since another winter has now passed (and somebody dragged this thread up from the depths!) I thought I'd post a follow up note.

Basically, the deck stayed almost perfectly flat throughout the winter rains. Face screwing did the trick. My boards are 1x6 and fastened with two #10 x 3" screws per joist. The joists are 4x6 and spaced roughly 16" apart. The screws are 1" in from each edge and countersunk about 3/8" below the surface. The way it's built now, the house will fall down before the deck will...

Glad to hear the project finally laid down BH. There is no real differance between 1x6/1x4 far as cupping goes,its just easier to see with 1x6. J

I wish I had found this thread before I spent thousands on a massaranduba deck!

I used 3/4" x 6" boards over 2 x 10 pressure treated wood and predrilled all of the holes. I used brass (color only?) screws with a hidden head (allen drive) and left-handed threads at the top 1/2", just below the head. Screws are about 4" apart over the joists, which are 16" apart. The deck is skirted.

After the first rains, the cupping started with a vengence, and it is due to the moisture. The boards snapped the screws in many places, and a few of the boards just popped up. I put a fan under the deck with the recent dry weather, and it's helped, but cupping is still there.

A contractor friend recommended different screws placed farther apart to reduce the cupping.

What type and size of screw would you recommend for this? Anything else I should do?

Well, it's been three years and my deck is still flat. As I mentioned in one of my earlier messages, it's screwed down with stainless steel (one of the stronger grades, but I don't remember which (304? 306?)) #10 x 3" screws, two per joist, spaced 1" in from the sides of the boards. All the holes are sealed and plugged...it was a great excuse to buy myself a drill press to cut the matching plugs.

Incidentally, I've been putting it off long enough...it's time to rebuild my other deck. Anybody in the San Jose, CA area want a small job?