Kitchen venting revisited with a new twist. I am in a process of installing downdraft in my island but I painfully realize that it won't be ever even 90% effective as the hood. Regrettably we do not like hood hanging from the sloped ceiling over the island. Therefore, I'm thinking about installing a back-up exhaust fan in 45 degree slopped ceiling and that is the potential problem because I am not sure how I will be maintaining this not very easy accessible fan as it will eventually need to be cleaned from remaining cooking "pleasantries". I looked at couple of them and none come with any kind of filter and even if I found one, how I'll be able to reach it and service it. Sounds like a very difficult task. Any ideas?