Masonry adhesive: stone on block

[lynnbilodeau]

Short story: Need to permanently adhere natural stone to concrete blocks.

Long story: We terraced our back yard into four levels, and have put in 400 feet of block wall, using the locking Windsor stone type blocks. I have never liked the unfinished look of most Windsor walls, so we decided to cap with a natural stone. We used 12 x 12 tumbled silver mist stone about 2 inches thick. Yeah, the stone cost more than all the blocks but it gives it a great finished look.

I have already cut all of the stone and have it sitting on the block, but need to adhere it .... permanently. If I hit one with the mower, I don't want it to move.

If I had a small area, I would use one of the epoxy products in tubes, but believe that would be cost prohibitive for 400 feet of wall.

Seems like I remember a Sika product that came in 5 gallon buckets. Went to their website and couldn't find anything.

Any of you masonry pros have any suggestions. I am in Oklahoma, so it has to be able to live up to rain snow drought, severe heat (110) and cold (down to zero... yeah, I know that's not cold to you guys up North).

Thanks in advance for any help.

 

[nicksnothereman]

Short story: Need to permanently adhere natural stone to concrete blocks.

Long story: We terraced our back yard into four levels, and have put in 400 feet of block wall, using the locking Windsor stone type blocks. I have never liked the unfinished look of most Windsor walls, so we decided to cap with a natural stone. We used 12 x 12 tumbled silver mist stone about 2 inches thick. Yeah, the stone cost more than all the blocks but it gives it a great finished look.

I have already cut all of the stone and have it sitting on the block, but need to adhere it .... permanently. If I hit one with the mower, I don't want it to move.

If I had a small area, I would use one of the epoxy products in tubes, but believe that would be cost prohibitive for 400 feet of wall.

Seems like I remember a Sika product that came in 5 gallon buckets. Went to their website and couldn't find anything.

Any of you masonry pros have any suggestions. I am in Oklahoma, so it has to be able to live up to rain snow drought, severe heat (110) and cold (down to zero... yeah, I know that's not cold to you guys up North).

Thanks in advance for any help.

Well I'd guess it needs to be elastometric. I'd probably use the "concrete" patch (in a tub) to a degree it doesn't show then use mortar to fill the cracks (if possible). Depends on how it looks after it's put together.

Something you need to visualize or test before you actually do it if you don't want to take a chance doing it.

 

[JimVonBaden]

Why not use veneer mortar designed for it?

http://www.homedepot.com/p/SAKRETE-50-lb-Stone-Veneer-Mortar-65306213/100669876?N=5yc1vZbogdZ1z0u18h

This is what I used, and so far so good.

 

[lynnbilodeau]

Jim:

My limited experience is that the mortar products are simply not strong enough for something like this. I want something stronger and more permanent.

Nick: I am not going to mortar the cracks. The gaps are really tight. I will take a pic in the morning.

 

[Steevo]

I have used Liquid Nails Landscape Adhesive to put cap on stack block walls with excellent results. I did it in my last house, and ten years later the wall caps were still solidly fastened to the blocks.

I have just completed another stacked stone wall project at my current residence, and used the same product again, as I trust it to work.

All of my caps and stair treads are affixed with Liquid Nails Landscape Adhesive, as will be my natural stone caps on the columns.

 

[Kevin54]

What Steevo mentions.

I put a large patio on a coworkers house probably 10 years ago, maybe 9, and used the Liquid nails and the patio is still holding up just fine.

BTW....Steevo....that patio looks great. We are looking to use similar blocks on an existing patio to build up a wall, add a grill, and possibly a fireplace. HOPEFULLY!!!!

 

[JimVonBaden]

Jim:

My limited experience is that the mortar products are simply not strong enough for something like this. I want something stronger and more permanent.

Nick: I am not going to mortar the cracks. The gaps are really tight. I will take a pic in the morning.

I don't understand. That is exactly what they are designed to do!

These pavers are 2" thick.

 

[JimVonBaden]

By the way, I used PL1 on my retaining wall caps and a year later none of them are still adhered.

 

[lynnbilodeau]

Won't be using any of the PL products then.

Jim. The masonry stuff is fine for pillars. These are retaining walls, and the tops of most of them (360 feet) have grass right up to the edge. They will get hit with the mower. They will be walked on, sat on, and generally abused. The walls also have to allow moisture to seep through. We used permeable fabric behind them to allow the water to drip through.

I agree with Nick's assessment that there should be some elasticity. Steevo may have hit on the solution with liquid nails. I was almost certain I had run across a sika product just for things like this.

I will try and post some pics tomorrow.

 

[JimVonBaden]

If you are going to have that kind of activity on yours, Liquid Nails will not hold. Mine has grass and virtually no contact by anything but a weedeater, and they all broke loose nearly immediately. Fortunately they just sit there, so no glue is fine.

 

[lynnbilodeau]

These are the walls. They have been in place for 3 years now, are stable and function exactly as we wished. Just need to permanently adhere the stone to the tops.

Still have some work to do on my steps. Heading out in the yard right now to do that.

 

[kd3pc]

5200 marine adhesive...just make sure you want permanent.

I used it to make a lacrosse practice wall, using 12" square cement tiles 5200 on back and attached to a 3/4 inch sheet of plywood. That was 8 years ago and it is still solid.

 

[Trey T]

I would use mortar to set it and maybe ad some sort of additive to strengthen the mortar.

The key to adhering any types of mortar, glue, or sealant is preparation of the surfaces. If you have dust, the adhesion will be limited.

 

[Alan Douglas]

5200 marine adhesive...just make sure you want permanent.

Yup. Moisture won't affect it; that's how it cures. It's expensive but I would bet that four dabs at the corners would be enough.

 

[Tyberius]

I think a mechanical hold will be best. The prefabbed stuff has a groove like this

that will sit just fine and hold without much adhesive.

Another idea is to use rebar stakes and drill the underside of the blocks and mount the rebar in the ground and hook the blocks on.

 

[JimVonBaden]

These are the walls. They have been in place for 3 years now, are stable and function exactly as we wished. Just need to permanently adhere the stone to the tops.

Still have some work to do on my steps. Heading out in the yard right now to do that.

I understand this is your place, and you have a look you are going for, but I wouldn't cover those walls, they look damn nice like that. Additionally, those block are not really designed to be covered. They are gravity fit and held, and they shift a bit over time. No matter what you apply to them it will likely not hold completely. You will have parts falling off every year.

IF you really want the stone look, you should replace the walls with concrete block properly laid and supported, then veneer them with stone. Just my non-professional opinion.

Please do show us how it goes.

 

[lynnbilodeau]

A lot of the blocks are already in place with rebar. The outside corners (there aren't many) all have rebar from top through the bottom, through the base and into the ground.

Thanks for the compliment Jim. I have already purchased and cut all of the caps to fit, and we like the look as they sit with the caps.

The 5200 sounds promising. Yes, I am fine with PERMANENT.

As for prep, we plan to do this in August when we are getting no rain. I will flip all the capstones over behind the wall, clean the surfaces well, wait a day, brush off and then adhere.

Thanks for the input.

 

[JimVonBaden]

I need to fall on my sword, or something. I thought you were recovering the vertical part, not just new caps. My reading comprehension really *****!

All my veneer mortar comments are way off base and I apologize. Yes, there is likely some kind of adhesive that will work. Please let me know what you end up using and how strong it is. One day I need to reglue mine. Right now they are just resting on top.

My apologies!

 

[Zeke]

That's going to be a ton of work...



Literally.

 

[SteveCh]

That's a really nice wall. I would still use a mortar and doing the caps is easy, just slap it on the brick, set down the cap stone and tap it with a wooden mallet or whatever. Move to the next stone and do it. It gets pretty fast after the first few stones. If using mortar, dampen the bricks with the hose first.

 

[lynnbilodeau]

No problem Jim. I figured I wasn't being clear, or that something was misunderstood.

Most of the hard work is done. I terraced the back yard in four levels with a small tractor and a box blade. Had to relocate most of the sprinklers. What I couldn't get to with the tractor we did with hand shovels. We did most of the work during summer of 2011 when we had over 60 days of 100+ heat. Many of those were over 110. We would get up at 4:30 and work until the temp got to 100.... usually about 10:30 a.m. then get in the pool to cool off before heading to the office.

The walls are just about complete... except for adhering those capstones. Every stone around the curves has been scored and then chisel cut to fit perfectly to the next one. I just think the stone caps gives it a nice finished look.

The 5200 isn't too expensive in bulk. I have two brothers that sail, so they are probably familiar with it. Will give them a call.

Thanks again for the input.

 

[Alan Douglas]

"Bulk" I assume means a quantity of cartridges? Once a cartridge is opened and moisture gets to it, it starts curing. You might store an open one for a day but after that, the only way to get fresh material out is to cut the nozzle shorter or puncture the side.

Also be sure not to get it on clothes. It is impossible to remove, fresh or cured. Likewise on hands but eventually it will wear off.

 

[C96]

They are gravity fit and held, and they shift a bit over time. No matter what you apply to them it will likely not hold completely. You will have parts falling off every year.

^ ^ ^ ^ ^ This. I believe this to be accurate since it is somewhat of a free floating wall so to speak. I realize you are looking for something to adhere the top cap to the block, but since your caps overlap adjacent blocks as they should, the blocks are not rigidly set in mortar and grouted like a steel reinforced concrete block wall. Since the wall is not rigid it will shift as stated above and so will the caps. The shifting will cause any type of bond between the caps and the individual underlying blocks to eventually break loose.

I don’t think that type wall is meant to be caped the way you intend. If it is I’m sure the manufacture has specific purpose caps made to interlock with that block so everything can move independently of one another and still be secure.

By the way, nice job on the wall looks great!

Hope you find something suitable for the purpose.

Good Luck

 

[lynnbilodeau]

^ ^ ^ ^ ^ This. I believe this to be accurate since it is somewhat of a free floating wall so to speak. I realize you are looking for something to adhere the top cap to the block, but since your caps overlap adjacent blocks as they should, the blocks are not rigidly set in mortar and grouted like a steel reinforced concrete block wall. Since the wall is not rigid it will shift as stated above and so will the caps. The shifting will cause any type of bond between the caps and the individual underlying blocks to eventually break loose.

I don’t think that type wall is meant to be caped the way you intend. If it is I’m sure the manufacture has specific purpose caps made to interlock with that block so everything can move independently of one another and still be secure.

By the way, nice job on the wall looks great!

Hope you find something suitable for the purpose.

Good Luck

I SUSPECT you are correct. And yes, for the most part I made the capstones each contact two blocks, by design.

Looks like the 5200 has a bit of "give" built into it, which is exactly what I need. You are correct, in that the wall can move slightly over time. I do have some of the blocks on outside radiused curves "pinned" with 1/2 rebar just to make sure they don't move too much. Think I will buy a tube and test it in one of the areas that is likely to get hit by the mower.

I am fine if a capstone comes loose here and there over time. I don't mind re-attaching.

Thanks for the compliment. That wall in the first pic is about 80 feet long (interupted by a set of stairs) and it is less than 1/8 inch variance in height anywhere along the entire run. In addition to using an 8 foot level while working on it, we used a water level along the way to make sure we didn't get off track. Takes way longer to do, but I hate uneven looking masonry.

 

[theoldwizard1]

Looks like the 5200 has a bit of "give" built into it, which is exactly what I need.

As already stated, any non-cementitious adhesive needs a clean surface. The cleaner the better !

5200 is EXPENSIVE and does take DAYS to cure 100% !

 

[lynnbilodeau]

Talked to one of my brothers who is familiar with the 5200 and Vulkem 116 (about half the cost). The Vulkem is actually made for masonry. Both have some give. My brother's opinion was that the 5200 would be even stronger than the Vulkem. I can also purchase in bulk using his contractor's account, so it would be more affordable. We have so much time and effort in these walls that a few hundred dollars doesn't bother me when you look at the big picture.

My plan is to pick up one tube of each. See how far each goes on parts of a wall that won't get a lot of abuse. Wait two weeks and test how well each one holds.

 

[theoldwizard1]

Vulkem 116 looks a lot like PL Premium

 

[lynnbilodeau]

I glued down several stones with 5200 and several with Sikabond Construction Adhesive.

The Sika is about 4 bucks a tube cheaper, unless I can find a bulk deal on it. Not a big deal. I also like that the Sika is just a little bit thicker, so would fill gaps a little better.

Both products take 7 or 8 days to fully cure. After only two, I beat them both pretty good with a large hard rubber mallet. Doesn't look like either will let go. Both have just a little give to them, which is what I was after. I don't PLAN to hit them with the mower, but you know how that goes. Will wait a few more days and then really give each the torture test. Assuming both pass, will go with the cheaper product.

Will post.

BTW, here is what the Sika tube looks like.

 

[lynnbilodeau]

Well I am a big liar. I am using the more expensive stuff. I beat the **** out of both of these and neither one failed. Used a huge rubber stonework mallet. If I can't break it loose with that, I am sure the lawnmower scraping by once in a while won't do it.

So, why the 5200? Partly because my brother (a boater) talked me into it. He tried removing 5200 from some boat parts years ago, and just couldn't get the stuff to break loose. Also, I noticed when hitting it, there was just a bit more give, so it seems to be more flexible. For this app, that works best. If I hit it with the mower, it will give a little but bounce right back. I found it for about 11 bucks a tube (in bulk) from Jamestown Distributors in Rhode Island. I needed two cases. The extra $100 is no big deal considering the time effort and money we have in these walls.

Very nice on the phone and I got the product in 3 days. I glued down about 2/3 of it yesterday. I need to make a few cuts in some stones for final fit, and will hopefully have this wrapped up by the weekend.

Will post some pics when I am done.

 

[lynnbilodeau]

Well, I can tell you for certain the 5200 is amazing stuff. All the blocks are adhered. We are also doing some other landscaping (leveling, pulling a couple of stumps, putting in fence, sodding) and was using my tractor for those tasks. I was backing the tractor into an area where I could get to a stump on Sat. I wasn't paying attention and got a front wheel hung on a tree. The other front wheel went got caught on one of my glued on blocks. Didn't come loose. Pulling out of the same cramped space, I accidently ran over the one unsupported corner of the same stone with the back wheel of the tractor. The stone broke, but the bond held. Have to say I am impressed.
The main key is cleanliness. We hand scrubbed and then rinsed every surface. Let it dry for a day.
Very happy with the result. Even after the 8 day cure, there is some give to it.

Just went out to take a couple of pictures but the battery in the camera is dead.

 

[akdiesel]

lynnbilodeau

That is alot of of wall to cover. I have been using the Sika brand adhesive for a few years now and I am happy with its results. I did not not know about the 5200 stuff till you mentioned it. The Sika is easy for me to get and I have alot of rock to place on a new curved wall. Just a lengthy process with lots of wooden supports.

 

[Steve Works]

lynnbilodeau

That is alot of of wall to cover. I have been using the Sika brand adhesive for a few years now and I am happy with its results. I did not not know about the 5200 stuff till you mentioned it. The Sika is easy for me to get and I have alot of rock to place on a new curved wall. Just a lengthy process with lots of wooden supports.

I agree. Sika does a great job! I would recommend it to anyone interested.

 

[theoldwizard1]

Late to the party, but here is my 2¢

Most construction adhesives (Liquid Nail, PL Premium, etc) work fine for cap stones. I don't know how well they would work for vertical attachments, long term. Same potential problem as I mention with 5200 below.

Mortars work well for brick/block because they absorb some of the moisture. In hot weather some masons will dampen the block before applying mortar to attach the finish brick to lengthen the drying time and reduce the amount of moisture pulled out of the mortar. The point is, some natural rock are very non-porous and therefore "typical" mortar won't stick well to it. Maybe a professional mason can list an alternative.

5200 is AMAZING stuff ! $$$ !! It works well on slightly porous surfaces (almost nothing will stick to High-density polyethylene (HDPE) or Ultra-high-molecular-weight polyethylene (UHMW) )

The main key is cleanliness. We hand scrubbed and then rinsed every surface. Let it dry for a day.

Yep, the surfaces must be CLEAN ! If you have failure, I will bet it is because the face of the block failed. This could be from moisture getting into the block face and the freezing and thawing.