NW Ohio Build - Opinions welcome

[perrysburg]

Ok, so I've never done any masonry work in my life (I'm an IT guy) and hope I haven't made any major mistakes up to this point but I could use feedback and opinions going forward....

[perrysburg]

Re: NW Ohio Build - Opinions welcome

Foundation: Concrete pad (4" with rebar). did a dry stack of block with liquid nails in between each layer. Stucco with quickrete quickwall which claims you do not need to mortar between blocks because they use fiberglass material in their product. And finally countersink 4x4 treated lumber for shelf.

pad dimensions: 4' x 5'

[perrysburg]

Re: NW Ohio Build - Opinions welcome

Building concrete pad on top of treated lumber (using 2 32" x 40" pieces of durock as base). First image shows durock being pressed because I glued with liquid nails both sheets together and to the layer of 4x4's underneath.

Last pic shows finished stucco (sorry didn't take pictures during but only finished product) along with side view of pad where you can clearly make out the two pieces of durock.

[perrysburg]

Re: NW Ohio Build - Opinions welcome

So here's where it gets real: I started to lay out the fire brick. I have to completely disassemble once the foam glass arrives. I plan on installing 4" foam glass between the firebrick and concrete pad--hopefully no chance of the timbers getting hot enough for concern.

[perrysburg]

Re: NW Ohio Build - Opinions welcome

So here's my questions so far:
1.) Should I have any concern with using 4x4 timbers under a layer of firebrick, 4" foamglass and 4" concrete pad with regards to heat? I did leave 2 gaps between the timbers so that I could shoot an infrared thermometer to the bottom of the pad that sits on the lumber to monitor temperatures on the first few fires.
2.) If you look at the last image posted, there's is a small gap between the second and third brick on the left. When I go to do the mortar and spread the gap across all 13 bricks will I be alright or does every brick need to be flush with the next and essentially no mortar at all used on the end of the bricks that will be the ceiling?
3.) This one is really important... I have read everything I could find on the refractory mortar and specifically the "home brew" posted on this site. Under the "High Heat Mortar Primer" (pinned) section someone asked if Glass Block mortar could be used in lieu of sand, portland cement and lime for the home brew and no one replied with an answer. Per quickrete's site their block glass mortar contains all 3 and at approximately the correct ratios. It took me several hours of calling around and searching on google but I did finally find the fireclay in my area. So all I need now are the other three ingredients and if glass block mortar gets me the rest of the way there my life gets easier.

Per the post I'm referring to glass block mortar is:
1 part portland
1 part lime
4 part sand

[david s]

Re: NW Ohio Build - Opinions welcome

So here's my questions so far:
1.) Should I have any concern with using 4x4 timbers under a layer of firebrick, 4" foamglass and 4" concrete pad with regards to heat? I did leave 2 gaps between the timbers so that I could shoot an infrared thermometer to the bottom of the pad that sits on the lumber to monitor temperatures on the first few fires.
2.) If you look at the last image posted, there's is a small gap between the second and third brick on the left. When I go to do the mortar and spread the gap across all 13 bricks will I be alright or does every brick need to be flush with the next and essentially no mortar at all used on the end of the bricks that will be the ceiling?
3.) This one is really important... I have read everything I could find on the refractory mortar and specifically the "home brew" posted on this site. Under the FB Mortar (pinned) section someone asked if Glass Block mortar could be used in lieu of sand, portland cement and lime for the home brew and no one replied with an answer. Per quickrete's site their block glass mortar contains all 3 and at approximately the correct ratios. It took me several hours of calling around and searching on google but I did finally find the fireclay in my area. So all I need now are the other three ingredients and if glass block mortar gets me the rest of the way there my life gets easier.

Per the post I'm referring to glass block mortar is:
1 part portland
1 part lime
4 part sand

1. No
2. The bricks do not need to be in direct contact. Your mortar acts as the wedge holding each brick in position.
3. If that is the composition of the mortar, all you need is to add the clay.
It would probably be cheaper to buy all the ingredients separately and mix yourself.

[perrysburg]

Re: NW Ohio Build - Opinions welcome

Thanks for the reply!!!

[perrysburg]

Re: NW Ohio Build - Opinions welcome

Anyone have any personal experience substituting glass block mortar for the portland cement, lime and sand portion of the home brew?

and going with .....

3 part glass block mortar (pre-mixed)
1 part fireclay

[gugahulk]

Re: NW Ohio Build - Opinions welcome

I would not sleep if I had wood on the base of my oven, I was thinking about doing the same thing you did, but I decided not to as I would not sleep at night. Why did you decided to put wood on the base? Let me know as I think it will be easier to do than concrete. Thanks, by the way its looking awesome!

[deejayoh]

Re: NW Ohio Build - Opinions welcome

I don't think there is any problem with the wood - given that you've got 4 inches of concrete and 4 inches of insulation. It will barely get hot if at all

Not sure why you are looking to use glass block mortar. I assume because you have it already? I would go with homebrew. The mortar line item in your budget will be about $20 total. Really not a place where it is worth experimenting. But what you describe sounds pretty much like homebrew sans the fireclay. I would get that from your brick cuttings. Not worth buying a bag and then throwing away what you cut from the bricks by the bucketload.

[GianniFocaccia]

Re: NW Ohio Build - Opinions welcome

+1 on the homebrew. Better to be safe than sorry.

[perrysburg]

Re: NW Ohio Build - Opinions welcome

gugahulk -- I was on the fence when initially designing however, I saw a post where someone had done a similar build using wood and they did not have any heat issues. As a precaution though I did leave 2 gaps so that I can monitor (infrared thermometer) the base of the cement pad from below on the initial burns.

deejayoh -- Don't have any block glass mortar sitting around...Just thought it would be easier to get the right sand, lime and portland already mixed. There are several posts where people are concerned that they didn't get the correct type of sand (silica), and then there's the issue with lime--lowes and home deput both sell it in the garden section but there's an additive of soluble calcium. Not sure if that will mess things up but I get concerned when it's not just straight lime. So a little more work on my end finding the exact match for everything but if it's already correctly mixed and contained in the glass block mortar mix my life is easier. -A

link to the lime I referred to:
Shop Sta-Green 30-lbs Lime at Lowes.com

[gugahulk]

Re: NW Ohio Build - Opinions welcome

After I saw david s's post I was like ok. You should be ok as I was thinking you were going to put some time of insulation under the floor firebricks. So, i thought you should be ok as the insulation will protect the concrete and wood under it. But than I realised that you are using ZERO insulation under the firebricks floor. Wow, thats crazy. I am not an expert but that is scrary NO? Remember your oven will get 1000 F in there and that my friend is SUPER HOT. Over time even that treated wood will get drier and drier. I would always be worried. I did the same thing on my Brasilian BBQ you can see on my build. and I wish I didnt but I put 12 inches of concrete on top of that 2x4 treated wood. and on top of that I added 2 inches of insulation board and I am still worried. I build it to last me for ever. So, I tried to do it right and later found out that it was a mistake but its to late to correct it. But I hope you are ok my friend. I must say the base looks nice!

I have a question for you. I am building the same type of oven you are. Why did you choose wood for the base? Did you like the look? Was it easier to do than concrete? Why was it the final choice?

[Gulf]

Re: NW Ohio Build - Opinions welcome

...............There are several posts where people are concerned that they didn't get the correct type of sand (silica), and then there's the issue with lime--lowes and home deput both sell it in the garden section but there's an additive of soluble calcium. Not sure if that will mess things up but I get concerned when it's not just straight lime. So a little more work on my end finding the exact match for everything but if it's already correctly mixed and contained in the glass block mortar mix my life is easier. -A

link to the lime I referred to:
Shop Sta-Green 30-lbs Lime at Lowes.com

Perrysburg,

I did a very quick search for your area. I think, that these folks are fairly close to you.

Check out their miscellaneous products section.

They list masons lime, fireclay, and silica sand. You may have already checked them out. If not, a phone call might help you do some one stop shopping .

[perrysburg]

Re: NW Ohio Build - Opinions welcome

All, In my original post I stated --I plan on installing 4" on foamglass on top of the 4" pad of concrete which sits on top of the lumber. I'm waiting for the foamglass to arrive and laid out the brick directly on top of the concrete so I can start cutting the brick in anticipation of finally assembly. So NO I am not setting the firebrick directly on top of the concrete pad.

I understand if you missed that --I do it all the time skimming posts.

gugahulk - I used wood for both reasons (easier to build and aesthetics) but mostly for the aesthetics.