# Adhesive for Concrete Block Fire Pit



## 95025 (Nov 14, 2010)

Greetings Gents!

Simple question: What is the best adhesive for concrete blocks being used for a fire pit?



Background Story: This is for the church camp we go to. I threw this one together before a Men's Camp. 

The camp has a whole lot of these concrete blocks, and I got some "concrete caps" at Home Depot. About $50 did the deed.

I used Loctite PL500 Landscape Block Adhesive, but it didn't hold well at all. No big deal, because we're going to be dismantling and moving this fire pit anyway.

However, next spring I plan to make at least a couple more of these fire pits, and would like something that will hold more permanently. 

Suggestions?


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## de-nagorg (Feb 23, 2014)

Was it lined with FIREBRICK? 

No? Well there's your problem.

Fire will even cause most solid stone to flake off and degrade, if you get a hot fire going for a long time.


ED


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## 95025 (Nov 14, 2010)

de-nagorg said:


> Was it lined with FIREBRICK?
> 
> No? Well there's your problem.
> 
> ...


Nope. Not lined with fire brick, nor will they be. We're low budget.

Obviously a good hot flame is going to eventually destroy even the concrete blocks, but because we've got so many of them to use I'm just hoping for 3-4 years out of them.

Got any adhesive suggestions?


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## HenryMac (Sep 12, 2018)

The concrete blocks / caps will crack. The problem is the concrete blocks get wet, then if you build a big fire the water in the concrete expands and cracks the block. 

Lining it with firebrick will help, but if the concrete is wet, and it gets hot, it will crack.


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## de-nagorg (Feb 23, 2014)

DrHicks said:


> Nope. Not lined with fire brick, nor will they be. We're low budget.
> 
> Obviously a good hot flame is going to eventually destroy even the concrete blocks, but because we've got so many of them to use I'm just hoping for 3-4 years out of them.
> 
> Got any adhesive suggestions?


I have used this PL Premium Construction Adhesive, Made by OSI Sealants. 
www. stickwithpl.com , on many concrete landscape blocks, over the last 20 years, and they are still right where I stuck them. 

I have never tried it on a fire pit, but as an edging, small planter, capstones, and other blocks adhesive it sticks great. Holds strong, the block breaks next to the seam, not at the seam, before it breaks.

I did a test once long ago. 

It comes in a Red, Black and Yellow 29 oz tube, and you use a 1/8 inch bead to stick with. 

Any squeeze out, needs cleaned before it sets up, or it is a little ugly, but it depends on your taste I suppose. 

ED


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## SeniorSitizen (Sep 10, 2012)

NP 1 is another popular adhesive and lists stone color available if desired.


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## ClarenceBauer (Mar 4, 2005)

Why not look at using a fire rated High Performance caulking. That are used in a fire rated assemblys.


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## Canarywood1 (May 5, 2012)

NP 1 is not an adhesive, it's a sealant and should not be used in this instance.


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