It is very hard to find a kitchen fan the is not a hood for a tiny ADU with very minimal kitchen. We did one that was a remote fan in the attic (for the 3 sone max req) and added a grease filter to the round ceiling intake. It passed inspection, but was a lot of work to install. IT would be great to find one that meets the noise requirement that is not remote. We are looking for a microwave/hood combo that is 24" wide and meets the sones requirement for my current project. Also seems to be hard to find a bath fan that is through the wall and quiet.

Nate Russell  Beyond Efficiency Dan Johnson  Beyond Efficiency Dan McDunn  McDunn Construction do you have any specific products to share (and that we can then add to the database)?

We just built an ADU for the architect Charles Kahn at one of his properties. They had plenty of resources to try and source a kitchen fan that met the criteria you were looking for and ended up with a small hood anyhow, unable to find a solution. I managed to get something like what you mentioned (less sophisticated) past an inspector, but it shouldn't have passed.

I haven't looked for a 24" microhood combo.

Here is a panasonic wall mount bath fan. I have not used this, but looks pretty sweet. https://www.amazon.com/Panasonic-FV-08WQ1-WhisperWall-Wall-Mounted/dp/B…

ERV for ADU - we have put in loads of these https://www.supplyhouse.com/Panasonic-FV-04VE1-WhisperComfort-40-20-or-…. I have done Zehnder systems and other whole house ERVs as well. For 440 SF, these panasonic bath fans seem to be an elegant solution, not requiring a lot of extra thinking and moving plenty of air.

I like ducted mini-split. I have done 4-5 of them, including a crawl space one at an ADU. In the crawl space installation, I underestimated the amount of clearance I thought we could get away with for install/service and it was an incredible effort to get it done. One of my biggest regrets actually in my construction career was installing that ducted crawl space mini-split without leaving enough space in the crawl. Such a task. It will never come out of there in one piece! Like most people, I despise wall mount ones in common areas, but I wish I had sold this client on them. The ceiling ones are also not great, but we did manage to install a ceiling one in a living room area fairly elegantly recently. The ceiling was dropped over a bumped out window, and it being at a lower elevation and sort of outside the main room, really took it out of play visually. Feel free to send me an email and I can send you a photo and a plan view of it. danmcdunn@gmail.com

Thanks Dan! Regarding your offer to share photos of the ductless ceiling mini-split, I'd also love to see your install... if you want to share a few pics through an album, you can do that w your pro membership - see "New Album" option under the
+" dropdown in right part of nav. You can't caption each photo but can comment on the album

Panasonic WhisperValue DC FV-0810VSS1 is a 2-speed bath exhaust fan that may be installed in a wall. It fits into a 2x4 stud cavity. This one is quiet like their typical ceiling exhausts.

This fan uses a squashed 4" oval duct, so you might need this special duct fitting: Fantech FEL4, J-shaped low profile plastic elbow with 4" round discharge to outdoors.

One our our architect clients selected this 24" range hood for an ADU. It's listed in AHAM and meets the sone requirements. Fairly slim profile. Elica Toblino ETB424SS

Thanks for this info. I had been unable to find a model of panasonic bath fan that could be wall mounted....they all seemed to be discontinued. I'm glad it still exists. I'll check it out. For the hood What I need is a kitchen fan that is not a hood for a kitchen that only has a plug in induction burner and a microwave. A hood is too big. (Very tiny ADU. probably too small we have decided)

Sarah Deeds  Deeds Design , a bummer about using a kitchen exhaust fan is that the airflow req. are much higher—300CFM (vs for range hood: 160CFM for ADU<750 sq.ft). The Toblino that Dan shared is only .5 sones at working speed of 100CFM so this meets the noise req. even though it's 7 sones at 340CFM (see bottom of this doc: https://storage904.cdn-immedia.net/sites/default/files/elica_ss_2023_to…). From T24 compliance manual "The Energy Code requires verification that range hoods are HVI or AHAM-certified to provide at least one speed setting at which they can deliver at least 100 CFM at a noise level of 3 sones or less."

Also for microwave/hood combo check out HVI Certified Products Directory (https://www.hvi.org/hvi-certified-products-directory/section-i-complete…). 1) under Product Category filter by kitchen range hoods; 2) under Subcategory filter by microwave; then 3) click on "Model" column to consolidate ratings for the same model at different flow rates. Find models with a high setting ≥160CFM that also have a lower setting ≥100CFM that is ≤3 sone req. These ones work: IKEA 004.621.66 https://www.ikea.com/us/en/p/medelniva-over-the-range-microwave-black-s… - IKEA 204.621.65 https://www.ikea.com/us/en/p/uppseende-over-the-range-convection-microw… - other IKEA products, Blomberg, Midea, Electrolux etc. The trick I think is to find a product that has offers a lower setting around 100-120CFM; then it pretty much guaranteed will be <3 sones at that lower setting