I am in the process of installing two ceiling fans on my patio awning but want to know what the general requirements are in regards to the distance between the fans so they do not interact with each other?

What are the dimensions of the awning?

Usually, you would either divide the area by two, and put a fan in each center, or divide it by 3, and put a fan on each break. The first option is generally considered to be the better one.

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In regards to your question on the area of the awning, it is 10 feet depth x 36 feet long. I am trying to determine if I need 2 or 3 fans before I order the awning. I live in a very humid climate and need to make sure the air is always moving to keep it cool. I have talked to a couple of people and they have mentioned that if you have the ceiling fans too close, then the air may not circulate well between the fans and creates a dead area where no air circulates. Sounds plausible but have you heard of this before? And if so, is there a rule of thumb on the required distance between the fans so I do not create this dead area.

First of all, I always advocate using industrial/commercial fans for outdoor installations. Northwest Envirofan makes the very best ones. I do not like "traditional outdoor fans" at all. See:

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Based on those dimensions you could easily use three fans in 12x10' squares, however that is quite a lot of fan for the overall square footage, as most outdoor and industrial fans are only available in 52-56" (if you used 36-42" fans it'd be perfect). Two larger fans on 18x10' squares would be more than enough coverage but slightly less even. It's your call based on installation options, budget, and whether you want an overwhelming appearance of fan.