I have to repair a pump house where my well sits. The existing wood has rotted out. Obviously, it’s a damp environment. I want to glue and screw some pressure treated plywood to some PT 2×8’s. I figure I could use Gorilla glue or construction adhesive. Any advice would be appreciated.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
Skim-coating with joint compound covers texture, renews old drywall and plaster, and leaves smooth surfaces ready to paint.
Featured Video
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
You could glue with a waterproof construction adhesive, like PL-Premium.
However, in a damp environment, you may need to repair the structure again.
Glued components would complicate a future repair.
Why not use stainless steel screws instead?
Gord
A legitimate question. But I need some good strength and stiffness because a hinged door for access will be hung off it. Also, I figure if one of the glued up pieces decays the other will right along with it.
By the way, just to clarify, the operating environment will be damp but the plan is to assemble the details dry and then put in place. So the glue itself doesn't have to cure in a damp environment
It sounds to me like you are looking for a glue that will provide (or enhance)structural integrity for some door components. Glue is not the best choice for ensuring structural strength, especially in an outdoor environment. While PL Premium is rated as an exterior glue, the wood to which it's adhered will likely fail before the glue itself does.
Re-consider mechanical fastening techniques, such as screws. There really ought to be a way to do it without using glue. If you NEED the glue to hold this thing together, then maybe the original design is a bit marginal.
I agree that adhesive alone should not be used in this application. that's why I want a combination of adhesive and mechanical fastening. I'm a structural engineer for an aerospace company and adhesive + mechanical fastening is commonly used.
Wow, this thread has legs.
As Piffin and others mentioned, PL-Premium is an excellent all around adhesive, wet or dry.
I read about a test on adhesives where they submerged glued planks in the middle of a lake for 6 months. I believe only the boat building adhesives faired better than PL-Premium.
Gord
PL Premium is a polyurethene construction adhesive that cures with moisture. Made to order for you
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Doesn't Gorilla Glue also cure with moisture?George Patterson
Yes, it is also a polyurethene glue, but it is not a structural adhesive - more of a bonding glue.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I have not had good luck with Gorilla Glue and PT lumber.
"PL Premium is a polyurethene construction adhesive that cures with moisture."
are you sure about that part?
I'm going to go downstairs and read the label. I know Gorrila glue and other brands like it require moisture to cure. But I sure don't ever recall having to dampen my floorjoists before laying a bead of PL for it to cure. View Image View Image
You don't have to dampen them. There is enough already in the wood and in the atmosphere. gorilla and the premium are both polyurethene glues. GG has more expansion agents and is a woodworking glue typically used on dryer lumber and in woodworking projects often nofasstener other than the glue. the PL has more solids and does not expand as much, nor need to, but it is designed for a cconstruction adhesive to take the needed moisture found naturally and to be acceptable for damp joists normally found on contruction framing, which this job appears to be. The older constrution adhesives would often not adhere at all to damp wood or in old temps so it became more of a shim when cured than an adhesive glue joint.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
View Image
I just did a search, I think you should take over the PL website, you seem to know more about their glue than what they are willing to tell.
my opinion is that it is more accurate to describe PL construction adhesive as not being affected by moisture. as it cures in both dry and moist environments. But what do I know, I didn't make the glue, I just use the stuff.
Actually, I did find a PL glue online ( above) that I have not seen before. it's a polyurethane wood glue, but it requires surfaces to be dry - not moist like GG - interesting. View Image View Image
What you are showing is PL Premium WOOD GLUE and I have been speaking of PL Premium CONSTRUTION ADHESIVE - two diferent products but both are polyurethenes. Their wood glue similar to gorilla.http://www.stickwithpl.com/Products/detail.asp?PLProductID=14In responce to your suggestion, I took over their website and created this page for you...;)
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
"What you are showing is PL Premium WOOD GLUE and I have been speaking of PL Premium CONSTRUTION ADHESIVE - two diferent products but both are polyurethenes. Their wood glue similar to gorilla."
yes I know...sorry, did not mean to confuse things. I wrote that I found something I have not seen before, and thought i would post a pic of it.
I have also been talking about PL premium ( also known as construction adhesives) I believe that PL works just as well in the Arizona desert as in the damp BC coast that I live in. I stand to be corrected however, if I am shown solid evidence of the contrary. View Image View Image
LOL...dude that's the same site I got the picture from. if you click on did you know and scroll down you will find it under the wood glue.
They don't say anything on the site about PL Premium requiring moisture to cure, which is why I thought you should take over the site. View Image View Image
Notice the name of it is PL Polyurethene Premium?That is a fact of polyurethene - that it takes moisture to cure!The desert is definitely drier, but moisture still exists there
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
well...if that is indeed the case for all polyuerathane glues. that is something I did not know, and would have to take your word for it. where did you learn that? View Image View Image
I read a lot and subscibe to a newsletter on adhesives. The name of which is in the other PC right now, but I'm sure you could do a bit more google type research
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Maybe I should ad that construction related polyurethenes are of the moisture curing type - simply because there is moisture available and it is much easier than mixing with another kind of catalyst cureing agent.There are other kinds of polyurethenes availabl;e. You are just not likely to see them outside of an industrial setting.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Piffin,
I'm using the PL Premium on my stair stringers, where they attach to the first tier and the top headers.
Here in North Texas, at both Home Dep. and Lowes, a large cartridge of PL cost about $7...any idea where to buy it cheaper?
I also was wondering about how you get the stuff off your hands?
Thanks, Bill
geez Louise, it looks like your risers are only about 5" each!When You say large, I assume the quart or whatever that is, vs the 11oz one that I use mormally, which costs me about four bucks. You are getting a good price, it you are using the whole tube. If you are only using partial tubes, you are wasting a lot with such big ones.the PL Pr goes a lot further than typical construction adhesives because it flows well, needing a smaller hole cut in the tip and because it expands modestly. I get 60-80% more use from a 11oz tube on subfloors than I used to with PL 200 or 400 or whatever it was. That alone makes it quite a value.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Piffin,
The rise is actually 6-1/2"...You see, last year my wife fell and broke her ankle and the small bone in her leg, plus she has seen me crawl up and down those foldup-style stairs as I store things upstairs in my workshop...
So, knowing that old age will soon catch up to the both of us, I'm building a permanent staircase, with the stairs 48" wide and with "Old Folks" stairs. It takes out what seems like a lot of floorspace in the bottom level and taken from the top level, but when we carry things upstairs it will be safe and a lot easier...
I was wondering what a person uses to get the PL Premium off ones hands?
Thanks,
Bill
"I was wondering what a person uses to get the PL Premium off ones hands?"Me too, LOLI use a pumice stone in the shower. You can probably use something more potent on the job if you hit it within a couple of minutes after getting it on, but if you are a doctor or have other reason to keep especially clean without waiting for it to just wear off, wear gloves when you use the stuff
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
time
or a sand blaster
No matter how careful I am using PL Premiun, I always seem to get it on me. And despite what they say on the tube, any type of solvent just seems to spread it around.
thanks for the info Piffin View Image View Image
On the sell page they have "PL Premium's reactive nature allows the formation of high strength bonds quickly.".But they don't say what it reacts to, but as it is a one part product that can be used on multiple surfaces (air) moisture is the best suspect.But if you go to the technical data it has;"PL ¯ Premium Polyurethane Construction Adhesive is a polyurethane based one-component, moisture-curing adhesive.".
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Since your PT is going to be in a damp environment, in contact with the ground or whatever-
get the PT that's rated for ground contact. Its got a higher concentration or chemicals, and will last longer. You may have to search a bit for it, but I'd consider it.
There are construction adhesives (I think Liquid Nails is one) that are made especially for use on PT lumber. Usually have a sort of olive green color on the label.
Hopefully you have already solved this problem with PL Premium. I'll just say that my brother is now doing the exact type of construction (gazebo) and is having great success now that he is using the PL Premium that I recommended to him. He started trying just mechanical fasteners and was having large gaps open up even with screws spaced 6" apart as the PT wood dried out. The PL seams are tight. As Piffen quoted, their tech data sheet http://stickwithpl.com/pdf/PLr%20Premium%20Polyurethane%20Construction%20Adhesive%20Tech.pdf says "Premium Polyurethane Construction Adhesive is a polyurethane based one-component, moisturecuring adhesive. It is VOC compliant and contains no chlorinated solvents or water. PL Premium provides superior adhesion to most common construction materials. It can be used for interior or exterior projects and is three times as strong as conventional solvent base construction adhesives."
Edited 7/1/2007 8:07 pm ET by RichMast
appreciate it. thank a bunch.
I had a client last year who asked me to build a replacement well house for thier shallow well. Just an 8x8 doghouse type thing with a simple gable roof and an access hatch. Because it's a shallow well, only about 8' to water, my main concern was metals from the wood leaching into ground, and eventually into the water. I got the contact # for the PT manufacturer from my lumber yard and asked about using PT lumber in this application. I got a quick, stern, very legal sounding response..."PT lumber should NOT be allowed to come in contact with, or used in close proximity to potable water supplies". I questioned them in this, asking if it's only copper, what's the deal? They would not even entertain the discussion, just reiterating their original response, which I'm sure is their basic CYA position. I shared the info with the client and we decided to go with KD lumber and lots of ventilation in an effort to kept the moisture levels down inside the pump house. Just my 2 cents.