John Polk wrote:A very handy number to remember is 1.6
Divide the square footage of roof/catchment area by 1.6, and the results will be the gallons collected for each inch of rain.
A 1,600 sq. ft. house will collect 1,000 gallons for each inch of rain.
A 160 sq. ft. chicken coop will collect 100 gallons from that same inch of rain.
That is a helpful number. So a 1,600 square foot home is going to collect 16,000 gallons of water with 10" of rain a year, or almost a third of the suggested needs for a year. I was looking at closer to a thousand square feet, but also have plans for a greenhouse, garage and a small utility building/barn. A large water tank (sounds like I would need one) would be a useful catchment source, so I will likely have 3,000 sq. ft of roof to work with. I am fine with using
compost toilets, reclaiming greywater (I have not yet built the house so intend to plumb it accordingly). Probably a good place to start is to map out what I would like to do with the land, project that into water requirements and then go from there. I would also need to develop a rather disciplined mindset about life before I seriously entertain this idea.