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Concrete form release agent

ncproperties's picture

Anybody know a good home version for concrete release agent?

I know diesel fuel has been used but guy I’m working with swears it gets cut with something else but we just know what. So any ideas?

(post #108236, reply #1 of 25)

I have heard old timers say they mixed it with used motor oil or just used motor oil  on the forms the day before they set them.  He said it ran off over night and left a light coating.  We are doing a lot of structural grouting recently and have been spraying the base plates of the columns with Pam.  The grout wipes off easily and make cleanup the next day a breeze.  I have also used turtle wax or bowling alley wax ,and wd-40 on small form jobs.   The last three weeks we have been using epoxy grout, what a mess.  The forms have to be wrapped in poly, caulked to the base and at all joints.  You have to cover the everything with plastic.  This stuff sticks to everything and doesn't come up without taking concrete with it.

(post #108236, reply #2 of 25)

wood forms for flat work?  or molds for countertops?  form material?   the slicker your form the less need for a release agent... and what if any finish will be applied to/on your concrete after will also affect your choice now... or you will fight it later


(post #108236, reply #3 of 25)

I'm with spike - motor oil and diesel mixed ~1:1.

I did the forms for short stem wall that way a few years ago. Worked okay. It would probably work even better if you use MDO for your forms.


(post #108236, reply #4 of 25)

no no no no , oil effects the concrete, get some form release from your local construction materials dealer. everybody building green now. dont do something stupid using motor oil or diesel. well we been dong it that way thirty years. you been doing it wrong for thirty years.

Edited 4/23/2009 11:19 pm by brownbagg

If not not not then what? (post #108236, reply #25 of 25)

I also feel this may make a mess and possibly pollute/stain/destroy things it comes in contact with. I also think no no no. Do you know what is a good release agent?

(post #108236, reply #5 of 25)

I've used Mazola corn oil spray a number of times with pretty darn good results.



(post #108236, reply #6 of 25)

I've seen it here on BT that some have used Pam.

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(post #108236, reply #7 of 25)

I have used pam on some concrete sample forms, and even during cleanup. I have drop the mold in acid, the pam does not come off

(post #108236, reply #8 of 25)

No, nothing special that's why we don't want to bother getting real release agent, just wanna use something on hand. Small residential addition, site built ratty scrap 3/4" ply for wall and same on 2x12 footing plank. Never visible for inside existing basement or out side.

(post #108236, reply #14 of 25)

Brown bag got it right, if you don't want to do it correctly ,then throw the formwork out in the dumpster when your done. Diesel oil stains forever and stinks too. All the other ridiculous posts are just as dumb as being too lazy to buy a pumpsprayer and a couple of gallons of form release.I am sure throwing out the form work is much cheaper than spending ten minutes or so with a pump sprayer.

Pam,you nuts,how bout wd40 or johnsons paste wax.I 'm going now before I come up with a dozen more stupid comments.


(post #108236, reply #15 of 25)

I've worked heavy high end commercial concrete, structural/flat/architectural for over 10years, stadiums, hospitals, universities, for one of the top 100 rated concrete contractors in the country. All obviously very detailed spec jobs. It hasn't been until just in the last 5yrs. that true "enviro" friendly form release agents have been showing up on site. Right or wrong, cut or uncut with oil, diesel in a pump spray is what was used.

Now for this thread I asked the question of a substitute for release agent because I'm laid of with no usual access to just grabbing a jug from work and it's for a buddies SMALL side job. We're talking 8" wall less than 5' tall and under 19' lineal feet, all under ground. He's also usually only involved in remodels, decks, and roofs, not concrete. So it's one of those, that for a whole oz. of what's needed over buying even just a gallon that'll never get used up, what might be usable on hand.

You can't tell me any one of us on here hasn't cut a corner in such a minor of a way.

Don't worry though we'll be sure to get a good thick coat of what ever we use on all the bar so it doesn't rust.

(post #108236, reply #16 of 25)

I prefer to have to coat my bar before we tie them, that way the overlaps are protected :) I love the smell of form oil in the morning.

(post #108236, reply #17 of 25)

Maybe I'm dense, but aren't you supposed to avoid getting the release agent on the rebar?


Jon Blakemore

Fredericksburg, VA


Jon Blakemore

Fredericksburg, VA

(post #108236, reply #18 of 25)

That's what I thought too.

(post #108236, reply #19 of 25)

You are  both right, i was joking around. A little concrete humor if you will.

(post #108236, reply #20 of 25)

You don't really need a release agent. All it does is make it strip a bit easier. But were all making it sound if we don't use some sort of release it can't be stripped. Which is simply not true, and the difference is not that huge in a lot of cases whether it is used or not.

If one uses a release agent, the panels will pull off a bit easier, but more so-  the panels need little if any cleaning. This is one of the big reasons that rental forms are saturated so heavily in form oil.

There was one time I had wished I had used a release agent. And that was when I had some form work with some inlayed panels. Because they were inset into the concrete, they were difficult to remove.

I recently finished a 2 month forming job at a new Stadium Ice arena. Which included slabs, planters, retaining walls and stairs. No release agent was used and stripping the forms was not a problem.

Either way, I think you'll be fine without a release agent for your buddy's small concrete job.

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(post #108236, reply #21 of 25)

Ya know, I've stripped and cleaned plenty of untreated and treated forms. Just love simmons' adjustable inside corners from the bottom of the wall!

Company I worked for when it was slow in the winter use to keep guys busy in the warehouse grinding and re-skinning truck loads of forms form the busy summer. They've switched to just renting instead of maintaining their own stock.

(post #108236, reply #22 of 25)

Update for future reference; Degreaser worked fine.

Used a 1gal. jug of degreaser mixed 50:50 with water and pump sprayer.

Now I'll admit it isn't something to spray on in the morning or day before as your forming It'll probably soak in and evaporate more than any oil based spray would. We sprayed it right before concrete arrived.

When my buddy came back from the store with it and asked if I thought it might work I said well it might if it doesn't just clean everything off the ply and make the concrete bond even better. But it worked better than I expected.

It doesn't hurt any to be stripping the morning immediately following either. I'd still like to see it put up against a cement heavy 6 sack mix sitting in place over the weekend to see if it has as much a benefit as a real release agent would.

However in this case it seems to have worked, was cheap, enviro friendly, and readily available. Any microscopic chemical impact in relation to the crete is unknown. Sure some engineers will chime in shortly with that criticism.

How long to leave the forms on? (post #108236, reply #23 of 25)

If I don't coat them, is it better to get them off next day or to wait?  Or does it matter?  I'm just pouring some 8x18 footings and a short (few inches) wall.

(post #108236, reply #9 of 25)

"I have drop the mold in acid, the Pam does not come off."

Kind of makes you wonder about the intestinal effects, doesn't it?


(post #108236, reply #10 of 25)

This is finehomebuilding.... not cook stalkers!!!!   LOL

(post #108236, reply #11 of 25)

Vegetable oil in a garden pump sprayer, or sheet poly if you don't mind a few wrinkles in the wall.

(post #108236, reply #12 of 25)

Right on. We considered veg oil, just weren't so sure about it, but you have actually seen it work before?

(post #108236, reply #13 of 25)

Seen it firsthand bro.

form release (post #108236, reply #24 of 25)

I have been using vegetable oil for about 6 years now and it works well, doesn't stink and is green.