Thanks. There will be ventilation. I'm just concerned that even with ventilation, there will still be a smell. Right now,
I use bleach if the dogs go - they are elderly dogs, used to a large backyard, they go on walks but sometimes they have to go out back. And I'm afraid they can't be trained to use the breezeway.This query is precautionary.

Don't use bleach on wood it breaks down the fibers

Yes, there certainly will be smell. I've lived in a city rowhome where neighbors had dogs and a concrete yard, and cleaned and hosed frequently. It's only a matter of time before that sickly urine smell permeates the air, esp. in the summer months. This vividly brings back bad olfactory memories - as if it were only yesterday. Yuck.

Ipe is not immune to dog pee...it will stain it and it will smell. If you really want Ipe and you really have to let the doggies go.....use Ipe tiles that you can take up and clean regularly (but as aidan said - not with bleach, you'll ruin the wood) - or just wait. Is there a drain in the concrete?

Thanks for the input. I really appreciate it. I have decided on putting up a small deck over the cellar door that will flatten and utilize the space (the cellar access is sloped and cannot be used as a gathering spot); the deck itself will provide an access panel. The rest of the backyard will be a patio with concrete or pavers. I'm hoping this is the best solution.