2 questions come to mind:

1-How do you air the house and keep the cats inside?

2-Do indoor cats need a special diet?

Hi, I don't have a problem with airing the house. I can open several windows due to having mesh screens on them. Great idea for people with indoor cats. I am a breeder of Siamese and do not let me breeding cats go outside for reasons mentioned earlier in the discussion. The cats are happy as they have everything they want and need indoors. There are 2 or 3 companies who make these screens and they are terrific.

As for feeding, my cats get the best quality dried and wet food but nothing special for indoor cats. You can buy indoor cat food but I don't think it is necessary.

I have a few cats who live in a different part of the house and they have free access to go out in the garden but then I live nowhere near a road. I have the ideal spot for cats. Unfortunately most people are not so lucky.

I think it can depend on the cat.
I have two, one is a born hunter and would climb the walls if not allowed out, I struggled to keep him from bolting out the door as a kitten untill he was neutered and allowed out, he is well fed but still comes and sits on the doorstep several times during space of a day with a mouse.
My other cat however who I want to go out has to be forced, he just wants to sleep all day and night, maybe he'll change with age he's still only a kitten (7 months), if he doesn't change I will probably just give in and let him stay in.
I have to say though that we live in the country where there is minimal risk of accidents, if I stayed in the town I might have a different view on this matter.

Personally I think indoor, as both parties benefits are greater.

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