Galvanized Metal Studs in Smoke House Build

[ifitsdeadsmokeit]

I have read through several build threads (havent made it through that many, maybe ten) and was wondering why nobody uses galvanized metal studs in their builds for a warm/cold smoker. I agree if it is a hot smoker ≥ 200° should probably not chance it. I read it has potential to off gas but as a cold/warm smoker for sausage, bacon, cheese, etc. I dont see an issue. I would think it would be a better long term option so the repeat heating doesnt dry out the wood. I am in the gathering information stage right now. Planning a 5' tall x ? x ? ( has to fit through door of my shop) electric smoker (220v). Any other suggestions are welcome. I am not using it above 200°. This is where I am at right now:

galvanized stud framing (possibly wood if talked out of it)
Hardibacker interior (dont think aluminum os stainless lining is needed)
Maple hanging racks for the rods
Insulated with rock wool
Exterior OSB siding (unless told by the better half I have to match the house) but will be stored inside my john deer room when not in use
High and low adjustable vents on opposite sides, screen to keep bugs out (thinking of adding a fan to promote air flow) (thinking flat roof or slightly angled, so gable locations are out)
220 v heating element (need to size)
Smoking It smoke generator (not sure if size is too big for a pellet tube)
Upper and lower doors
Firebrick bottom
Auberins or equal PID
Will be on casters so I can move it
Seal seams with high temp silicon

 

[SmokinEdge]

Personally I would have zero issues using those studs. They will not be directly exposed to the food anyway. Some folks get very cautious and understandably so with food, but being practical is necessary as well. Just my o2

 

[DougE]

Galvanized steel needs to get to almost 400°F before it starts releasing toxic gases. I wouldn't use it where it was close to the heat source but it's probably not an issue otherwise.

 

[chopsaw]

You'll have no issue at those temps . If I ever build one , that's what I'd use . What gauge are you thinking ? 20 ? Don't go less that that . Especially if using cement backer .

 

[JckDanls 07]

I'm ok with them as well...

 

[ifitsdeadsmokeit]

It will be 20 gauge. That is what I used in my outdoor kitchen.

 

[chopsaw]

Sounds like you have some knowledge of metal stud framing . If you would have any questions feel free to reach out .

 

[civilsmoker]

The studs are on the outside of the CC so they aren't interacting with the food.... you didn't ask about this but for me I personally wouldn't use Hardibacker for the interior (ie I'm not a fan of a possible concrete dust into food...I use cement mixed with peanut butter in a box trap to keep the mice out of the yard...one bite and they are toast)...... I would much rather have a 18 or 20 gauge skin that has been seasoned (carbon steel or stainless).....or a natural wood skin....

 

[chopsaw]

you didn't ask about this but for me I personally wouldn't use Hardibacker

I wasn't going to say it again , so glad you did . To many use it . The stuff is full of chemicals .
No way I would use it .

 

[ifitsdeadsmokeit]

My lack of being able to cut and bend metal steers me away from it, especially when getting into 20 gauge. My skills with metal studs is just enough to be dangerous, kinda like my masonry work.

Here is my outdoor kitchen i built in CO.

Here is mine in MO

 

[civilsmoker]

My lack of being able to cut and bend metal steers me away from it, especially when getting into 20 gauge. My skills with metal studs is just enough to be dangerous, kinda like my masonry work.

Here is my outdoor kitchen i built in CO.
View attachment 715863

View attachment 715864

View attachment 715865


View attachment 715866
Here is mine in MO
View attachment 715867

You don't need shears, ie a 4 inch angle grinder from HF 9.99 and couple of 1.00 cutting wheels. Lay it on a 2x4 with a metal stud guide or just a straight piece of wood (3/4 or 1/2 inch ply works great) clamped to the sheet and run the wheel down the guide..... Bingo. FYI the wood backing keeps the cutting wheel from catching and kicking back....let the cut edge fall away so it doesn't bind the wheel.....This is easier than cutting metal studs.....

PS, I would much rather cut steel that that cement board.......Cut the panels then use food grade silicone for seal the corners to make it air tight (no bending required)......easy peazy.....if you can build what you did above you can cut a sheet or two of thin gauge....

 

[Fueling Around]

No problem with steel studs either.
You don't the extra expense and difficulties with rock wool either. Fiberglass is good for at least 200°
However, it you get the urge to go make it a hot smoker the rules change.

The studs are on the outside of the CC so they aren't interacting with the food.... you didn't ask about this but for me I personally wouldn't use Hardibacker for the interior (ie I'm not a fan of a possible concrete dust into food...I use cement mixed with peanut butter in a box trap to keep the mice out of the yard...one bite and they are toast)...... I would much rather have a 18 or 20 gauge skin that has been seasoned (carbon steel or stainless).....or a natural wood skin....

Besides the concrete dust, backer is fiber (fiberglass) reinforced concrete (FRC) and the fiberglass dust is not healthy as well.

What is your mouse killer formula? We use the Coumadin laced bricks, but the dead mice lying around are fair game to the farm dog or wildlife. I'm thinking a lime poisoning would be less toxic.

I wouldn't use a metal skin interior unless over a wood liner. A metal skin in direct contact with steel studs with telegraph heat to the exterior. A wood alone interior would be my choice.

 

[ifitsdeadsmokeit]

Didnt think about using the grinder with a guide. Sounds easy enough. Hardest part could be sourcing the sheets.

Not worried about cutting the hardi, I use a face respirator. I am concerned some about the cement board contamination The idea was to get away from wood. So why is there a difference between having wood liner directly exposed to the heat as to having it transfer through the metal facing and studs to the exterior wood?

 

[DougE]

ou don't need shears, ie a 4 inch angle grinder from HF 9.99 and couple of 1.00 cutting wheels. Lay it on a 2x4 with a metal stud guide or just a straight piece of wood (3/4 or 1/2 inch ply works great) clamped to the sheet and run the wheel down the guide..... Bingo.

I do 1/4 and 3/8 plate the same way. Usually do the first pass along a straight edge to score my line, then just remove it and make several more passes until the material is cut through.

 

[ifitsdeadsmokeit]

What thickness wheel would you use to cut 16 or 20 gauge?

 

[Fueling Around]

...
The idea was to get away from wood. So why is there a difference between having wood liner directly exposed to the heat as to having it transfer through the metal facing and studs to the exterior wood?

A metal skin is only needed if you didn't want wood on the interior. For a home made smoker I would prefer a wood interior.
I was stating a metal interior directly to the steel studs is a no as it will conduct heat and create cool spots

 

[civilsmoker]

What thickness wheel would you use to cut 16 or 20 gauge?

1/16” or 3/32……ie the thin cuter ones ones

A metal skin is only needed if you didn't want wood on the interior. For a home made smoker I would prefer a wood interior.
I was stating a metal interior directly to the steel studs is a no as it will conduct heat and create cool spots

Yes a natural wood for a smoke house is pretty traditional…..metal ie SS with radios corners for food service……….

 

[civilsmoker]

I do 1/4 and 3/8 plate the same way. Usually do the first pass along a straight edge to score my line, then just remove it and make several more passes until the material is cut through.

Yes once the groove is defined it’s just light passes back and forth….. I always us a guide for straight cuts!!!

 

[chopsaw]

What thickness wheel would you use to cut 16 or 20 gauge?

Like this . Better buy a bunch if ripping thin metal .
Eats them up fast .

Not worried about cutting the hardi, I use a face respirator. I am concerned some about the cement board contamination The idea was to get away from wood.

I never used a saw to cut cement board , we always used a razor knife , or they make a cement board knife . Score and break . You don't need advice on that . Your work looks fantastic .

The cement board is full of chemicals . Never saw fiberglass in any , but silica and cellulose are a big part of it . Some brands have a plastic netting to hold it together .

Remember , all the specs you read on cement board are from an " as intended " use and installation .

So why is there a difference between having wood liner directly exposed to the heat as to having it transfer through the metal facing and studs to the exterior wood?

The issue is the metal framing transfers sound and temperature more that wood . Even with wood installed on the studs you'll get a higher degree of transfer because of the screws .
The way to stop that is the use of horizontal furring strips .
Strips screw to the studs , then the interior finish attaches to the furring , making sure the screw don't contact the studs .
You can buy DWC ( Drywall channel ) or RC-1 ( resilient channel ) .
In your case I would use wood furring strips , and plywood finish in the inside .
I'd fur the outside as well , to keep the colder temps out , and the inside to keep the heat in .

 

[mike243]

I wouldn’t put fans in it and just small adjustable vents, the more air movement the more heat it will take, i dont see a little heat transfer will hurt as you lose some regardless of what it is up against, if never over 200 I would use cedar, after a few smokes it will be sealed up and probably never rot. It will draft enough with natural convection, as heat rises as long as the vents are in place you won’t have stale smoke unless you have a over abundance of it, a nice maze would probably be able to tune the smoke a little better than a tube, lower amounts in it or higher amounts, a tube has to be packed pretty tite. Shag bark off a hickory with some pellets really gives good smoke so don’t be afraid to test 1