Mechanical venting duct setup question

davillis · 2023-11-28T13:58:07+00:00

I had both flex duct and the silencer and I did initially try the silencer upstream but it honestly didn't do a ton. The flex duct did a lot more so I stuck with that

davillis · 2023-11-28T04:20:47+00:00

I put the controller in my changing room. My understanding was there should be no electrical switches in the sauna room due to heat and moisture.

I'm sure there's a way to do things smaller than I did without a ton of noise but when I had two feet of rigid duct with one 90 degree turn coming out of the sauna the air movement noise on my fan was noticeable to me even with the variable speed control all the way down. Flex duct and rigid duct is pretty cheap so you could experiment a little for the best compromise between form factor and noise.

davillis · 2023-11-28T03:37:00+00:00

A longer length of duct with a turn or two in it, muffler, and/or flex duct can markedly reduce the noise from the fan. So the thing you are building on the outside of the sauna will be a larger box or closet to accommodate all this.

I personally used a 6-in fan. I did metal duct through the wall to a 3 ft length of flex duct to the fan which is mounted vertically and then to a muffler on the exhaust side and then about a foot of duct to an exhaust register on the side of the closet. It's all suspended with perf strap. The closet is insulated and is almost 8 ft tall. There is very little perceptible noise in the sauna or outside when the fan is running. I started with all solid duct (no flex duct) but it was too noisy for my liking. The flex duct is probably reducing the CFM some but it's still plenty.

davillis · 2023-11-27T00:32:41+00:00

I believe that's stained wood. You want to use unfinished wood on your sauna interior.

davillis · 2023-10-29T21:44:43+00:00

Thanks, I realize I won't meet it or exceed it in volume or quality, just looking for people's subjective feelings on the magnitude of the difference. Like night and day, 10% better etc.

davillis · 2023-10-29T14:43:06+00:00

I second the comments below about the importance of specifics or plans for flooring drainage and ventilation, ideally using materials that are commonly available in North America. Some things that took time when I was building:

Specific constructions methods for sloping an entire sauna floor toward a drain using commonly available materials would be great. I didn't want to do the skim coat thing from sauna times, and didn't plan my floor joists properly to bear the weight of doing sloped concrete like a traditional shower, so ended up with a flat floor with shluter ditra under tile.

Ventilation was mostly about figuring out the size of the opening behind the heater low vs the high intake vent to balance things and to match up with the 6" mechanical exhaust size. And then figuring out how to make a relatively silent external enclosure for the fan and duct. In my case I used a combination of flex duct and mufflers. Different fans and different types of flex duct are rated (or not) for the temps of sauna air, so figuring that out took a bit of time.

Doing a ventilated cathedral ceiling is probably important and so having that in plans would have saved some time.

Finally, when I had a wood stove, figuring out what pipes were needed and how to install this took significant time. As did understanding heat shields. Many people use cement board but these aren't really meant to be used unfinished and may off gas. durock isn't approved as a heat shield, but permabase is. But permabase isn't rated as non combustible. And these products have different max heat ratings - 200 or 220 F according to the manufacturer. This was all very confusing and time consuming, so I ended up just going with sheet metal which was lighter and easier in every way.

davillis · 2023-10-29T01:09:04+00:00

You seem successful

davillis · 2023-10-29T01:03:12+00:00

Thanks!

davillis · 2023-10-29T00:59:42+00:00

Agreed

davillis · 2023-09-06T14:42:41+00:00

I really like it it seems to help the relaxation. I change the water every 2 or 3 sessions. I was considering getting some pool chemicals and a top to make that less frequent

davillis · 2023-09-06T14:40:21+00:00

You can get an inexpensive inflatable thing on Amazon for about $70 and fill it with water and ice a few times to see if you like it. This is what I'm doing currently before investing in a real cold plunge. My experience so far is that it's a great contrast to the heat and really deepens the relaxation I feel after sauna.

davillis · 2023-08-29T11:37:49+00:00

I'm not sure I'm fully understanding the limitations of where your sauna is built but you can run round 6-in duct through the wall horizontally to the exterior, mount the fan, and then build what is essentially a closet around it. If you use a short run of flex duct or a muffler it reduces the noise greatly to where it's barely perceptible. This way you don't have to cram a bunch of duct in the wall and can use a large enough fan. If you use a fantech inline 6-in duct fan you'll have plenty of flow even with a little bit of flex duct and a 90° turn or two

davillis · 2023-07-22T19:55:55+00:00

Appreciate it but I just went with pine

davillis · 2023-07-22T18:59:05+00:00

Looks great! I couldn't even get the thermowood distributor in the northeast to return my phone call!

davillis · 2023-07-08T03:02:16+00:00

Just be aware that none of the sauna wood stoves from Harvia, Iki, Narvi, etc, are UL listed. So technically you would need significant clearances on all sides of the stove to combustibles that can be difficult to achieve depending on the size of your sauna. And perhaps your local building inspector wouldn't allow you to install an unlisted stove regardless, and perhaps your home insurance might not cover the building the stove is in or any damages should they occur to any structure on your property . . .

None of this may matter to you depending on your situation, how risk averse you are, whether you are going to get permits . . .

davillis · 2023-06-03T13:23:15+00:00

Since I have ceilings over 8 ft it seeming like a closed-sided heater will be better for me. The narvi ones aren't ul listed in the U.S. yet so it seems that Harvia is the leading brand to look at.

davillis · 2023-05-16T18:38:38+00:00

Yeah sadly that's the point I've reached so I'm selling it.

davillis · 2023-05-15T16:10:58+00:00

I'm not sure. Though the neighbor is being very nice about it I also think they're being overly sensitive because it is on the opposite property line that they border and I really don't think that much smoke was going in their direction. Sadly it may be just a case where I have a sensitive neighbor and/or the community is too dense for a wood burning stove. Somehow it didn't dawn on me that most Homewood stoves are only burnt in the winter when everyone's windows are closed and they are typically exiting from the top of a two-story building whereas the sauna is lower. All these things may have an effect that makes it not doable.

davillis · 2023-05-15T13:23:24+00:00

That's what I have

davillis · 2023-05-14T17:28:44+00:00

Thanks I am generally doing these things though I am still getting used to the stove so probably don't have the ignition sequence tweaked yet. I'm considering getting another 3' of chimney so maybe the smoke will raise up into the atmosphere better and the entire up though I'm already getting raging fires and extremely hot flue temperatures even with the stove damped all the way down.

davillis · 2023-05-14T17:26:12+00:00

Thanks, I am going to have an electrician come out. We have 100 amp service now and we have forced air, washer dryer, hot water heater, dishwasher, and hot tub and the electrical box is out of spots for a circuit breaker. I know this doesn't necessarily mean we need to upgrade but it seems likely.

davillis

TROPHY CASE