I collected rain water off the office roof for a while - it has a rubber roof - and found that the water was really soft and great for washing hair - then I started feeling a little sick from it and stopped and went back to regular water. The water off the roof would be foamy for a while until it got washed clean from heavy rain. Who knows what was leaching into the runoff water from the rubber etc. but I did treat it with Iodine. It would also leave an oily film in the collection bucket - too many diesel trucks going by as well as polution in the air and the building oil fired heating system.
Most good collection systems will runoff the first few minutes of collection to get rid of all that junk (and also use a purification system and a runoff to prevent freezing). If I did this I would do it well, with a large tank and a purification system and early rain junk diverter.
You can get plastc barrels from truck or bus washing places, such as a large city bus company, or a commercial truck wash along the interstate. Also, a bottling plant for coke or pepsi etc usually gets syrup in drums. Around here they are available for $5 each. We have a 500 gallon stainless steel bulk tank, from a defunct dairy farm, that we use to collect rainwater from the garage roof, also a 200 gallon brine (salt) tank from a commercial/industrial water softener. I also got a 1500 gallon poly tank from the local farm store when it was on sale (under $400) and am hooking up eavestrough on one of our outbuildings to feed into it. It is enough higher than the garden and orchard that we will have gravity feed to the plantings.
they used rain collectors in Florida years ago. they look like over sized dog houses but hold water, they are capped to keep the mosquitoes from multiplying. mainly used for watering lawns/gardens washing cars.
You would definitely want to use plastic, I think. I like the idea a lot.
If you wanted to really jazz it up, a small 12v battery, a solar panel, and a small 12v bilge pump would be sweet. But maybe that technology steals the simple beauty of a rain barrel.
Not sure where you would put the barrel, but remember that when full it will weigh about 500 lbs.
I like this idea quite a lot -- the city had plans for them at the Home Show last year. We have really crappy grass that needs watering to survive (plus I don't plan on using fertilizer unless it's easy on the evirons). On top of that, there are some drainage issues in the back (pooling). Reducing the need to use treated water to dump on the lawn seems like a great idea.
I picture something like this: 55-gallon drum or 2 in the basement - Roof water and/or sump water could drain into the tank - design an overflow for safety - and rig up a pump/power supply, ideally solar.
This idea has really piqued my interest. Doing a quick Internet search noted several companies with mostly large, complex systems.
The concerns I have:
1) Design: For gravity collection from all 4 spout corners and aesthetics, the collection tanks should probably go in the basement.
2) Source: The downspouts -- there are a few types to modulate collection: a design that hooks a hose/tube to the spout to reroute overflow back down the spout or just a rubber boot on the rectangular end with a reducer.
3) Distribution-Fill: I suppose flexible piping could run around the house and into a drilled and silicone-sealed hole in the side of the house. Following the floor joists for support and then into the tank(s) would work -- I'm looking for easy install here.
4) Overflow: It either rains a lot or a little. Since the sump may work less, it seems like a reasonable place for an overflow drain. I can see the system being used more than to let the supply get too high and flow-over.
5) Distribution-Output: a water pump to a lawn/garden/flower water system or hose with scheduled timer. At first, an electric system would be tried to see if the whole thing works -- then upgrade to solar with batts (it might make a good backup for the sump too).
6) Optional Power: Solar panels with batts. It might make a good power supply for the sump, or a backup. There's plenty of sunlight on the SW corner of the house, where the sump and planned tank location is.
BTW, how much water does a home A/C system traditionally extract?
Does anyone have a system, or can recommend any part of the design? The same for supplies -- where to get the goods? I've gotta make the house more efficient: it's embarrassing.