Bathroom Exhaust Fan for Kitchen Use
drewfridley7
| Posted in General Questions on
There is a good deal on Facebook Market for an 80 cfm bathroom exhaust. I am building a 190 sq ft tiny house and will use an energy recovery ventilator. I would also like to use an exhaust above my cooking area to get those particles out of the air created from cooking. Are there any differences in bathroom and kitchen exhaust mechanisms that would stop me from using one labeled for bathroom in my kitchen area?
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Replies
If it's for over a cooktop it has to be rated for that use, it has to have some sort of fire screen.
Now I’m wondering if I can get this one and DIY something by cutting away the plastic grates, making the capture hole larger (based on recommendation from comment #2), and put a fire-rated screen in it.
drewfridley7,
I'm not that familiar with your codes, but reading IMC 505.1, there are a lot of other requirements which it won't comply with.
If you mounted it somewhere else in the kitchen than over the stove I think it would be fine, but again we come back to the problem being no matter where you put it, it will be largely ineffectual at doing what kitchen exhausts are for.
drewfidley7,
It will also have next to no capture area, meaning you will move a lot of air without getting rid of many particulates.
Do you have any thoughts on what I said in comment #3?
I think you'd come out ahead using something like this:
https://www.build.com/product/summary/1821330?uid=4321264&&&&&msclkid=421323b516951ec4ce4e47bb8bf4599e&gclid=421323b516951ec4ce4e47bb8bf4599e&gclsrc=3p.ds
200 bucks, it has all the parts you need. There may even be cheaper ones, it was the first one Google found for me.
There are some key differences between kitchen and bath exhausts. The fan housing, fan blades and all ducting should be metal in a kitchen exhaust specifically to address fire risk. Additionally, you'll want a hood (as in an exhaust hood) within 24" or so of the cook surface (electric) or 32" (gas) if you want to do a good job of capture.
Your ERV will have requirements for minimum return duct distance and placement from a cook top (not close), but if you want to keep oil, vapours etc. out of your tiny home, you really will want a dedicated kitchen exhaust hood in play as close as code will allow to your cook surface. If you've ever cooked in a VW camper (I have!) or even a 30' RV (which all generally have typical kitchen exhaust hoods), you'll find out very quickly why most people avoid cooking inside if they can. Everything inside will smell like your last meal for some time unless you can sort a very effective kitchen exhaust.
That insert DC linked would work, but you'll need to sort a hood. Go check out a few RVs in a local showroom and see what they are using for kitchen exhaust. You may not need a 12V version (as they use) but it will give you an idea on design.
drewfridley7,
Another aspect of this is that Tiny Houses encompass two very different things: Small stand alone dwelling units, and owner built RVs. If it's the latter, building codes don't typically apply and you can use whatever you want.