I am an apprentice carpenter and recently I was at a lumberyard and I was told that green deck screws were not sold anymore because the ceramic surface cracks whens your screw gun screws it in leaving it to rust within weeks. Can anyone tell me if this is true?
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
Fine Homebuilding is excited to be the official media partner of the 2024 Building Science Symposium series! This event offers builders, tradesmen, architects, designers and suppliers to discuss topics ranging…
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
That has not been my expierence, although green screws is kind of a generic term. I used to build decks but am in another line of work now.... However my favorite screw was/is Deckmate - and yes, they are green.
That may be as a result of the newer pressure treated wood chemicals, which the green were for. The ceramic can come off, but there is still a zinc coating layer under that. But against the new formulation, it might well be true that it starts disolving right away.
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
2nd the Deck Mates. Very strong and quite corrosion resistant.
They are not stainless, but very good.
Driving them once barely scratches the coating, but they still resist rust.
Driving them multiple times can chew up the heads. More of the coating stays on the threads if you use a lube, like toilet wax.
How do you incorporate toilet wax? I mean, rub it on the threads of the screw before you drive it in or what?
Just curious, sounds interesting...Justin Fink - FHB Editorial
How do you incorporate toilet wax? I mean, rub it on the threads of the screw before you drive it in or what? "
Justin,
Never heard of using "toilet wax" but I suppose it would work. There are semi-rigid grease compounds sold for this purpose that also do double duty as anti-clogging grease used when grinding (with a disk sander) softer non-ferrous metals.
Jon
"How do you incorporate toilet wax? I mean, rub it on the threads of the screw before you drive it in or what? "
That's right. Toilet wax ring has the perfect consistency to be a thread lube, plus it is super cheap. One 99 cent (or less) ring will last a very long time.
The screws go in with so much less effort that batteries will last much longer, the bits will last longer, you are less likely to get cam-out, and fasteners are less likely to snap. (Cam out and snapping are not a problem with Deck Mates)
Particularly useful for temporary assemblies, since the screws will come out with less effort as well.
I have no scientific proof, but I theorize that the wax adds a bit of water repellancy to the wood around the fastener as a secondary benefit, thus rot resistance.
You can buy specialized thread lube compounds, but the lowly wax ring is much cheaper, readily available, and works great.
I keep a chunk of beeswax handy. It is not so messy and will not melt in the California summer. I sink the screw most of the way and back it out. Now the screw is hot. I touch the wax to the shank and the wax melts onto the shank. Now drive the screw home.Mike Callahan, Lake Tahoe, Ca.
" I sink the screw most of the way and back it out. Now the screw is hot."
An interesting technique, but I would find the double-drive to be too much work.
A small price to pay in the pursuit of quality craftmanship.
'Nemo me impune lacesset'No one will provoke me with impunity
Don't use Deck Mates!!! I'm having to replace all the screws on two decks because after 6 months 80% have broken where the threads meet the shank. They don't work on the new treated lumber. Use SS only!NCtim
Holy cow! Is that down there in North Carolina?
Were these the same Deckmate screws that say for use in ACQ?
Be some real news here!
'Nemo me impune lacesset'No one will provoke me with impunity
Yes! They still sell them at the big box stores, right in the pressure treat aisle.
When you say "broken", you mean physically snapped off?
In my testing, the wood always failed before the screws in tension.
Snapped right off. I found the problem reading another thread here. I went out and checked my brand new porch and thought some of the screws looked like they had backed out. Went to tighten them and they just spun. So, I get a small pry bar and started popping those suckers out. 8 in 10 just came right out.
Check out the other discussion here about a month or so ago.
Very curious about your results.
Were the screws holding down deck boards (in tension), or holding together something structural (probably shear)?
Also, did the threaded section break, or was it in the shank?
What length were the screws, if you can recall?
2½" Deck Mate screws holding 5/4 decking to joists. Broke in the minimal airspace between deck board and joist. Usually the second thread after the shank. BTW, this deck is a screened porch under a vaulted roof.
The deck outside in the weather had about a 60% failure rate. Not sure what this construes. Either way I'm never using them again and I've told all my buddies to throw them away. I've got a red face because I talked quite a few of them into these things over the past five years.
Sure wish someone would do their *&$% homework before they change stuff. I have a close friend who owns a pressure treating company and after thirty years he's had no problems with employees. They change the formula and all of his long timers have quit. Reactions, allergies, health care costs . . .
Government in action, or I should say, freakin eco nuts. Same with the soy craze in printing. All that soy bean ink is worse to get rid of than the linseed oil ink. It's both organic but the bean oil doesn't ever dry to a hard film. Which means it leachs into the ground water at a faster rate when you throw that piece of junk mail away.
Don't get me started . . .
"2½" Deck Mate screws holding 5/4 decking to joists."
Wow, and the 2 1/2 ones have the thicker gauge (thicker than the shorter screws). Very disturbing.
were those screwed in with impact drivers, it is not hard to shear them that way .. see current thread on Help me choose an impact driver ...
Those were DeckMate Square Drives right, definitly not the Grip Rite?
What kind of wood, what thickness was it, and what size (# and length) did you use? Also, what did you use to drive them in?
I'm very curious about this too - you seem to have an obnoxiously high failure rate there.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
The screwman returneth.
Now we'll get to the bottom of the story.
View Image
'Nemo me impune lacesset'No one will provoke me with impunity
Is that classic Al Jaffe?Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Close.
be a Sergio Aragones
'Nemo me impune lacesset'No one will provoke me with impunity
Hey Paul, see above for most of the answers. The wood is southern yellow pine treated with the new ACS or ACQ treatment. Nasty stuff, don't get it on you.
Used a Deck Mate driver chucked in a drywall driver, predrilled every hole with a counter sink bit, (I know, I'm a fanatic), I like clean installs and tight deck boards.
BTW, this wood shrinks way more than the previous treated wood.
It sounds like:
A: You had a bad batch of screws
or
B: The wood shrunk so much that ANY fastener would have failed.
SS is alot weaker than the Deckmates, I doubt they would have fared any better. Nails would have pulled right out. 80% failure rate is so dramatic the manufacturer has to know.
You should call the people at Phillips who make Deckmate. They also make fasteners for aerospace - they might be REALLY interested in what happened to you.
William St. Angelo Phillips Screw Company President, Commercial Licensing Division P.O. Box 869Bellingham, MA 02019 Tel: 774-396-6190 Fax: 508-966-2326 E-mail: [email protected]
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Edited 12/9/2005 2:37 am ET by xxPaulCPxx
SS is alot weaker than the Deckmates, I doubt they would have fared any better.
That is exactly what I've been thinking as I follow this thread.....
Good idea, Paul. Thanks for the contact info.
So, do you feel like the failure was due to corrosion or just weak metal?
I definately agree that the manafactuere needs to be involved. Is it too late?
Edited 12/9/2005 6:41 am ET by Matt
You probably had a bad lot of screws. The correct processing for screws with a zinc plating require a pre and post bake for a minimum of 4 hours at nearly 400 degrees. If this is not done properly there is a good chance the screws will experience a delayed brittle failure due to hydrogen embrittlement. You will usually see the failure occur within 24 hours installation.
However, if the failure mode was due to torsion there may be other metalurgical reasons. The point is that the ASTM standards have been relatively unchanged for decades. The engineering behind the design of fasteners is very fine tuned. You had nothing more than a bad lot of screws.
I'd like to think so. Even though they're going to give me replacements, would you go back and install the same thing? You know what they say, "fool me once, . . . "
I was out measuring the shank on their #9 3.5" screw, and that came out to be 1"... which would be the same thickness as the 5/4 decking material you laid. I'm thinking that you may have inadvertantly chosen the wrong screw for this.
If the #8 2.5" screw has a shank of .5", that places it at the middle of your decking. Shrinkage will cause shear forces on the weakest part of the screw - the threads.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Speaking from a non-theoretical point of view no one who's time is important uses 3.5" screws for installing 1" thick decking.
I wasn't suggesting that - besides which Phillips doesn't provide HD with the 25lb boxes that the other screws come in.
The #8 3" screw does have the same 1" long shank though, and does come in the large qty boxes. Looking around, I see that 2.5" for 5/4 decking is standard... still that seems thin to me. I would think the 1/3 - 2/3 rule would still apply there.
View Image
So how much time is saved using 2.5" screws rather than 3" screws?Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Paul, Matt was speaking of 3.5 inch screws, not 3 inch.
'Nemo me impune lacesset'No one will provoke me with impunity
Paul:
I have found that the 3.5" #9 screws are significantly harder to drive and require predrilling both in the "attached piece" as well as the "attached to piece". Also, many professionals use Quick-Drive (sp?) systems for decking board installation and I believe they do not come in either 3.5" and maybe not even 3".
The 1/3 - 2/3 rule of thumb is a good one and a sound theory, I'm just talking reality here...
As far as your statement >> So how much time is saved using 2.5" screws rather than 3" screws? << I have one Q for you that I'd like you to answer honestly: How long have you been working on your garage rehab project of yours? Granted, I'm sure the strength of what you have built is rarely seen in residential construction, but I think the real difference might be doing it as a hobby VS working in a competitive environment with actual customers. Don't get me wrong - nothing is too good for my customers, .... but they have to pay for what they get too. Building superior homes is not so much the challenge - delivering value is.
I agree that the #9's are harder to drive. I wish that Phillips would make some changes to that line... like giving them a self drilling point AND making the #9 size available in shorter lengths. But that's just me geekin out on screws;)
I do understand trying to balance performance and value, but I don't understand how going with a slightly shorter screw pays off in the long run. It might be a little cheaper per box, they might go in a little faster, and it might weigh a little less to transport. But wouldn't that all get eaten right up again with one callback due to shrinkage breaking them across the threads?
Really, I'm not trying to bust your nuts here Matt. I do really want to know how this works. Do 2.5" screws really normally never break across their threads like what happened to the poster here? You're right I'm being theoretical here... theoreticly a wood deck exposed to the elements would go though more stress than a covered installation.
Thanks for asking about my ongoing project:) Slowly but surely... actually driving the screws is the fast part. The rest of the time is spent trying to figure out what I want to do, where, with what. I always wish I knew as well as you guys how it all goes together!
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
This is the first time I've heard about screws breaking off - other than at the time they are driven. I still gotta wonder if it was simply a bad lot, or maybe even there was an installation mistake - like maybe they were overdriven. I think the manufacture should definitely be involved.
You can mail order #10 in any length you want from McFeelys. Check out their Promax screws, optimized for particular apps (screwing 5/8, 2x).McFeelys did a comparison of torque strength of their screws with "Big Box" screws, assuming this was not GripRite excrement, their screws were significantly stronger (more extensive heat-treating, they claim). I don't think they published it on their web site, I read it in one of their catalogs.BTW I finally found a place in Northern Joisey that carries GRK screws.....Got some #12 screws.....Their RSS structural screws look pretty serious and the shear ratings on them are very impressive.....
Yes, I have some of the ProMax screws already - love 'em, love 'em, love 'em,!Rebuilding my home in Cypress, CA
Also a CRX fanatic!
If you use anything longer than 2.5" screws for 5/8" decking you're just asking for pucker.
If ignorance is bliss why aren't more people
happy?
Well, for 5/8 the 2.5" screw would be the right length, theoreticly.
What is pucker, BTW?Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Imagine that you drive a screw two inches into a piece of wood, and let's assume, for the sake of argument, that the entire imbedded length of the screw is threaded. Now visualize the wood shrinking, say, 1/8" in 2". What happens to the screw, given that what was 2" of screw is now imbedded in 1-7/8" of wood?
What will happen, approximately, is that the screw will "split the difference" -- on one end it will go 1/16" deeper into the wood, while on the other end 1/16" will be pushed out. This will cause whatever's being secured by the screw to separate from the surface by 1/16" -- pucker.
Note that if the imbedded thread length is only 1" then only 1" will shrink, there will be only 1/16" of shrinkage in the wood, and only 1/32" of screw pushed out of the woood.
If ignorance is bliss why aren't more people happy?
Edited 12/11/2005 9:53 pm by DanH
That is a really interesting idea of what happens. I wouldn't have guessed the directional nature of the shrinkage and assumed it would shrink uniformly in from the two sides and therefore expose screw at both ends as the wood contracted. why do you think the screw "moves" in one direction?
I used 3" ss bugle head screws for holding down 2x6 green and kiln dried cedar on ACZA treated green douglas fir. i'm curious to see what happens as things come into (moisture) equilibrium, both during this (wet)/rainy) winter and in the later months of the (dry) summer.
has anyone seen good literature on the topic of deck design with respect to wood dimensional/moisture fluctuation?
I **did** assume uniform shrinkage, which is why only half (roughly) of the shrinkage results in movement of the screw. The point is that the wood shrinks and the screw doesn't, and the longer the screw the more of this shrinkage difference you'll have. This is why you want to use the shortest screw that will be effective for the job at hand, whether installing decking or drywall.
If ignorance is bliss why aren't more people
happy?
Thanks for clearing that up. i wasn't properly visualizing the scenario. it makes sense when you think of it in terms of screwing down a 2x6 onto a joist. i took you literally and just imagined a piece of screw 2" long in a 2" thick piece of wood, in which case i'd expect 1/16" protrusion of the screw on both ends due to the shrinkage. i've got a lot of this deck work to do, so, am interested in the concepts, which aren't clear or discussed well in any literature that i have found. and looking at the "pro" work in my neighborhood has not helped either. aaaah the joys of a DIY'er... beats going to the gym.
The main point is that if a 2-1/2" screw is good, a 3-1/2" screw isn't necesarily better -- never use a longer screw than is needed in terms holding power.It is unfortunately true that it's often difficult to find a screw of sufficient diameter in an appropriately short length. The big box stores don't tend to carry a complete selection, and you may occasionally have to use a longer screw just to get sufficient diameter, if you can't arrange to get the right screw from a better-equipped supplier.
If ignorance is bliss why aren't more people
happy?
Ditto on the broken Deckmates. Must be a southern thing. Here in Sw Va
I have 1600 sq. ft. of 5/4 x 6 popping screws like toothpicks, I used three on the ends and 2- 1 1/4 in from edges at the joists. I first assumed it was just screws that were too small for the job. 60 to 80 per cent appears to match my experiences. I believe I should have used 2's. I'm just glad this mistake was on my own personal project. Am I going to replace all the screws. H&*% NO!! Am I going to use or recommend Deckmate Screws, H&*% NO!! A junkyard guarantee is a very small reward!!! I'll Buy the new screws if Deckmate will replace them.
Edited 12/12/2005 10:17 pm ET by xanvil
I used deckmate 2.5" sq. screws with my dewalt 18v drill on 5/4 composite decking. Had no problem considering I used about 1800 screws. We will see in time but overall I was very pleased with the results. Keep us posted with the deckmates.
I 6thought I'd replace some and see what happens. To answer others' questions here, I predrilled all the holes because I knew there would be a shrinkage issue.
I also replaced some screws, on the ends mostly, where all were
broken and the board had curled. I had more breaks on the uncovered sections of the porches.
Please let us know what Deckmate says. Dito to NC Tim
Edited 12/14/2005 6:58 am ET by Matt
Fasteners are my business. I had an issue with installation screws for a major cabinet maker. The issue involved the potential for cabinets to fall off the walls after installation. They are still using the same screws from the manufacturer...just different lot. So to answer your question, Yes, I would use the replacements.
Good thing I predrilled all the holes so they're easy to pull out.
I've used the square drive SS screws on mahogany decking recently and did not love them. The drive strips quite easily. You will half of the time strip them if you ever need to take them out. Once that happens you have a darn hard time drilling them out just to remove the board. The SS seems to be just tooo soft for me to fall in love with it. The only reason I do like them is that they are very thin. I'm tempted to go back to common nails.
Everything rusts eventually except for stainless. I don't like using screws. Most of the time I use nails. It's just a personal preference.
Screwing the deck down has been in the vogue for about 15 years now and we are just now realizing that to refinish a deck is not an option with most screws because the boards will be ruined when you try to remove them because every other screw will strip or break.
If you insist on screws than use square or torx drive stainless. Only an amateur would use a phillips drive screw. Only an old fart would use nails.
Another vote for deck screws. I've almost quit using drywall screws - except for actual drywall work - lol.
I've never seen green deck screws. Around here they're either a tan color, or red. I used them (the red ones) to screw down my deck boards about three yrs ago and they're still in great shape.
If you use Deck-Mate screws, make sure you use their bit. They may look like a standard phillips, but they aren't. A standard #2 phillips will cam out of a Deck-Mate in a heartbeat - their bit doesn't.
A number 2 square bit works even better on the deckmates than the supplied bits do.