Pressure Treated and Simpson Hangers
hotwheels
| Posted in Construction Techniques on
I am using pressure treated 4×4 in a shed foundation — because of how I made the girders, I need to use a Simpson Strong Tie HCC (concealed hanger)to hang the four corners, but this connector is not made in their Zmax series for use with pressure treated wood.
I was advised by one person that if I paint the non-zmax hanger with Rustoleum that I can use them with pressure treated wood. Will this work?
Replies
I'd suggest an isolation membrane, Grace or maybe 30# felt, then use SS fasteners. Even the SS will react with the galvanized, but I think you'd be okay. Paint ? I wouldn't count on it.
Greg
Thanks for the replies ... I think I will use the Grace barrier. I have already painted the hangers, so I can use the Grace barrier with that and use Hot Dipped nails and ACQ screws. At first I was just going to use some 6 mill plastic, but I think the Grace barrier will be more sturdy and provide a more effective barrier.Thanks!
Instead of paint, I'd suggest spraying the hangers with cold galvanizing compound. It's easy to find and works well. Then wrap the ends of the PT with Grace Vycor or similar. Also, do not mix galvanized hangers/hardware with SS fastener or vice-versa.
I've used the galvanizing cold spray on foundation bolts when I've shown up to frame a house and the mud guys didn't use hot dipped foundation anchors.
When Plan A isn't possible, the cold spray is a decent Plan B.
View ImageView Image
Galv spray still reacts with the new P.T. lumbar.
Right, that's why I suggested isolating the PT from the hanger itself with Vycor. What would your suggestion be... seeing as the piece of hardware he needs isn't available with Z-max coatings or SS?View Image
Its hard for me to give a good suggestion without a picture or drawing, but I would use epoxy paint since it has no reaction with the metal or wood. Epoxy is also much more durable than rusto or galv spray. I should have been more specfic in my post to you. Two questions. Why would you paint a galivanize hanger with galivanize paint? And how do you isolate the anchor bolts? Even if you do isolate the bolts water could still get trapped below where you painted and rot the anchor from with in the concrete.
My point was that sometimes you have to play the hand you get dealt. If I show up to frame a house and the GC or his subs weren't on the ball enough to use the appropriate hardware, I can make the decision to do nothing, or make some sort of a compromise. Like I said, in both the situation I've described and the situation of the original poster, neither "plan B" is ideal... it's a compromise. If it wasn't.... it'd have been Plan A... which is planning accordingly and using the best materials for the job.
And to answer your specific question, I would add additional galvanization to a galvanized hanger to increase the working life of the piece of hardware in question. Since he can't get the piece of hardware he truly needs, he's looking for some sort of compromise. Galvanized hardware is perfectly acceptable to use with ACQ lumber..... if the ACQ and it's corrosive properties are sufficiently isolated from the hardware in question.View Image
Very useful suggestion ... I will get some of the galvanized spray to use with some other hardware I already bought for joist hangers ... the ones I prefer to use are not made in zmax. The zmax hangers are more appear to be more awkard to nail unless I use a plam nalier. At this point I have invested enough in the Simpson hardware that using the Grace barrier with what I have plus the galvanized spray will give me some comfort the foundation will be firm for awhile.I did use the Grace ice and water shield stuff I had in the garage for the HCC hangers and although it was time consuming to get the 4x4s level/flush with one another, it did work out and I think this solution works. I would not make sense in a production environment, but I think it will work for this situation.Thanks for the help!!! I don't work much with pressure treated lumber so this has been a learning experience.
I understand where you are coming from you have to improvise for others poor craftsmanship. (kudos for fixing instead of doing nothing) I just know from my experience in bridge construction and fabricating that cold galv does not work all that good for preventing corrosion. Epoxy on the other hand does. Plus there is no extra steps to isolate the P.T. from the hardware. Paint it and forget about it. You asked for my suggestion and I gave take it or leave it.
Someplace in the archives is a post about acq screws with a picture posted of a 'for acq' coated screw which had been left inside a covered garage laying on top of a acq 4x4 end I believe it was and left for several weeks.
That screw tho' protected from outside weather had serious rust forming on it.
Just a note to compare various claims of hot dipped and acq rated screws.
No easy answers.
Peaceful,easy feelin'.
92277.1
ACQ vs nail.
Didn't find any photos of a screw - just the smallish bright common nail. 3d? 4d?
JimNever underestimate the value of a sharp pencil or good light.
That was the thread I was thinking of. Quick comment. My bad.
I'm still hesitant over the use of some bigbox purchased 'coated for ACQ use' screws
recalling my own experience removing some ACQ decking boards on a small exposed porch and finding, tho' not to the degree of the bright common in reference, rust corrosion on the screws after less than a year.
Peaceful,easy feelin'.
Ummm... I am using nails in most places. I was using the ACQ screws that I bought at my lumber yard, not a box store, although they appear to be the same brand. I bought a palm nailer this morning so that should encourage me to use nails more than screws.
does anyone think that ACQ that rust through nails in less than one year might be worse for the enviroment than previous pt? I think somehow we have been sold a bill of goods.
You're just imagining that overall costs went wwwaaaayyyy up.
Double dipped hot zinc or stainless fasteners I believe is the recommended schedule for exposed exterior environments
and some have recommended that in addition to painting the hangers that a gasket of felt paper or something akin be placed between the PT and the hangers
to prevent or retard the corrosive spread of the chemical leaching reaching the metal.
Peaceful,
easy feelin'.
Grace works really well. If you have multiple fasteners just cut a pattern since they are all the same, peel and stick, and frame. Couldn't be easier.
Update: I have been wrapping the hangers and pressure treated lumber with A grace product, but in looking online for something completely unrelated, well sort of unrelated -- a mini grip palm nailer -- I found these "joist jackets." Although they are for a different purpose, it might work for my application: http://www.joistjacket.com/
Try 3M spray car under coat that you can purchase at most good auto supply houses. Much better choice than any paint and easy to use. Jay
My experience (many years ago) with the undercoat materials is that at least some are pretty soft and can be easily scraped off - I would worry that you would scrape off too much of the undercoat when you insert the 4x4 into the hanger. As suggested above, I think the epoxy coating would be the best solution, although perhaps something like the material that they sell for spraying on pickup beds would work.
Your correct some products are junk. I got the idea a year back from some car nuts I know. All swore by 3M undercoat they said stay away from everything else. I have used it now on joist hangers, and the back of exterior metal door frames that may see moisture. Only time will tell but it seems like some tough stuff. Jay
Isolate the hanger with vinyl coil stock scraps or something similar.
mike
Although some of the ideas posted here will work I still would stick to epoxy rebar paint. It's cheep, it's fast and it's reliable. No question as to weather it will last, rub off or have any reaction to the chemicals in the P.T. It will actually bond to the hanger, as long as it's clean. Paint will just coat it and all other options you have to cut something to fit. If I had a lot of hangers I sure wouldn't take more time than I had to if I could get the same or better result with another method.
Cutting the Grace stick on product does take a little time, but not awful. If it was production, then that would be another issue and I might look for another solution. The hangers I painted with Rustoleum would not have been a good solution on their own, since when I put in a few of the joists, the paint came off. Fortunately, the Grace product provides the backup.But, it does take time.Do you think the epoxy rebar paint would hold up to pounding a tight fitting 4x4 into a joist hanger?Thanks
JR
Yes, as long as the hanger is free of any oil before applying. I use the stuff all time in constructing bridges. As long as it's applied properly it is almost indestructible. I also have used it in your application with much success. It's the same thing as garage floor paint accept it's not 2 part, it comes in a spray can.It has a more adhesive property than regular paint.
I have a few hangers to finish, so I think I will try this ... good suggestion.
thanks,
JR
Where do I buy rebar epoxy paint? Thanks
I have bought it at H.D. Any commerical builder supply or steel supplier should have it. I say rebar paint because that is what I have used, any epoxy spray paint should do the trick.