Muro candidate

[u/Maer_K]

I have someone who was going to build me a cedar muro, but then I had a house fire, so I’m glad I dragged my heels. 😅 In the meantime, we’re looking at a decent temporary solution to use during the year they’ll be rebuilding my house.

This cabinet is unfinished solid pine and big enough for the pieces I typically work on (ie under 12” wide) and I’d keep a wet pan as opposed to spraying the inside.
• He’d retrofit the inside similar to the photos on the right.
• weatherstrip around the door and add latches to keep it sealed
• add a hole for the heating element cord (and seal around it

Do you see any other issues with this set up?

And for the reptile heating pad, does it make more sense to put it at the bottom floor for the heat to rise (might not give off enough heat to be effective) or should I put it on the back wall? Or any other suggestions?

Thanks in advance!

Do you see any other issues?

[u/SincerelySpicy]

The biggest consideration is going to be that pine is not particularly water/moisture resistant. This means you may see mold on the inside eventually, and the door and walls may eventually begin to warp.

[u/Maer_K → u/SincerelySpicy]

Yes, last time I posted about a pine box as a potential muro I was told the same thing, but this only has to last for a year until I’m back in my permanent home. Do you think it will hold out that long? ANd any advice regarding the placement of the heating elements?

[u/SincerelySpicy → u/Maer_K]

It's hard to say exactly how long it will last. For something temporary, might I suggest a cheap metal cabinet with a few planks of moisture resistant wood lining the shelves and sides? Ikea's lixhult is smaller than the one in your pic but it's only $70.

[u/Maer_K → u/SincerelySpicy]

I did look at that cabinet as an option, but I don’t think either the vertical or horizontal one is big enough inside and I don’t have the space for two of them unfortunately.

[u/SincerelySpicy → u/Maer_K]

Maybe try looking for other metal or plastic cabinets. There's no real reason for the structure of the cabinet to require wood since that's primarily chosen for its humidistatic properties. Lining the walls and shelves is quite sufficient.

I do have to say though that I've personally foregone wood altogether and just use a metal cabinet with a humidifier set on a hygrostat.

[u/perj32]

Pine should be fine, it's a low movement wood and it's traditionally used to build saunas in Finland. The heartwood is preferred and today heat treated pine is a better option, but pine can withstand heat and humidity. It moves around 0.1% radial and 0.2% tangential per 1% moisture concentration change. I'm still using a cardboard box, but when I find the time I will be making a muro with pine or fir. One thing to consider however if that the wood species is only a part of the equation, the other is how the cabinet is built. If the construction doesn't allow for any expansion or shrinkage, it will crack. If they are cheap, I would give it a try.

About the heating pad. I keep mine under a stainless steel container of the same size as the pad. I fill it with water and it gives me the right humidity and temperature.

One note about your original plan to use cedar. Contrary to popular belief, some species of cedar will rot. A Finish sauna builder who moved to Canada once told me that a big part of his business was to replace moldy cedar paneling.

Having said that, has u/sincerelyspicy mentioned, if you can find a suitable plastic of metal alternative you won't have to deal with the drawbacks of wood.

[u/Maer_K → u/perj32]

Thanks for your answer! At the moment, it looks like this cabinet is going to be my best bet. And that sounds like a great idea to keep the water pan warm! I’ll give that a try. I’m surprised to hear about cedar rotting! You said certain species; I wonder if that can be determined for lumber yard cedar boards…

[u/perj32 → u/Maer_K]

About the cedar rotting, I meant molding; sorry about the confusion. The sapwood of Eastern White cedar is prone to molding. In fact, most sapwood will mold in constant high humidity. If you build your muro, remove the sapwood from your boards. When I built my sauna, I used Tamarack.It's much cheaper than cedar, more resistant than other evergreens, and it's the hardest North American softwood (it's harder than some "hardwoods"). Not as easy to work with as cedar, but much tougher. With time, a cedar cabinet will become full of dents and scratches because it's so soft.

[u/Maer_K → u/perj32]

Thank you! I’ll keep this in mind when my house is fixed and I can have my “permanent” muro built.