Amazing statement, that the system is near free. Here is what I see at my site: 1) house has a footprint of about 1300 sqft, but two of the six gutters are devoted to ostrich fern, a high water perennial. So is half the detached garage (to hardy kiwi), which has no gutters anyway. I have 1000 sqft to conserve into 2200 sqft of garden. None of this water runs off, it all percolates into the ground and supports trees and the water table. 2) Need to replace gutter covers, because they stop leaves, but let in elm seeds. It is also a Cape Cod, with nooks and crannies in the roof where stuff congregates, decays and washes off. Things are much better now, since the ash trees died (also purveyors of small seeds), and I cut five spruce. No way to filter all that junk while tons of water are washing into the barrels. That will be quite a penny. Just to give you an idea, where my driveway empties into the lawn, I have to shovel elm seeds with a snow shovel in season. 3) The facility (18 barrels) weighs a lot more than the garage, probably half the house. It needs its own concrete foundation, and good retainment. I am guessing it needs 150 ft of 4X4 and 300 ft of 2X4, plus bolts, etc. I cannot build it near the house or the city will get me. In the back of the garage, I need a nice 5 inches pipe (at least, it has to collect all the rain of 1000 ft during a rainstorm) running 60 ft through the lawn, at a slope of 1 inch per foot, with some nice posts in the middle of the lawn which I will bless every time I have to mow. The barrels may be free (I never found them, and I have two, each of which I paid $10), but I still have to take delivery, or make nine car trips (plus all the trips for the wood). That is no money? My barrels come from 27 miles out. 4) The braising of the plastic barrels. I have no tools, and no one I know has them. They cost, and probably a couple of barrels will be lost. Now, to get into the 21 beds, I need 1500 ft of PVC, and probably 100 connectors and 100 elbows. If the system is to be done right, the end caps must be removable at the end of the season to flush the lines. I need valves in many places, because in August the tomatoes need zero water, and the celery, 2 inches a week. 5) we are left with the simple matter of drilling holes. Perhaps as few as 2000 (but in beds with carrots or lettuce, you need many more), but because they are drilled, their overall area exceeds the area of the PVC, unlike, say, in drip irrigation. That means the system loses pressure quickly, and the far beds get a lot less water. And all this to save water that is insufficient, irregular in its supply, and ecologically clean but technically dirty. It has the appeal of being in liquid form, but there is a lot more of it being lost to evaporation (and mulch really is free). It is water I would never put in my drip system, and a drip system, also, is something that truly saves water, and can be put in in a couple of days of work, and it saves water whether it rains or not.

I am collecting water in two rain barrels that are standing under downspouts. I am also collecting big plastic jars from juices and so on. When my barrel is full and i have time, i fill my collection of jars with water. In spring i use these jars to surround some plantings. It works like Wall of Water for my tomatoes, which i surround with jars and cover with row cover together with jars. Water will heat during day and release heat during night. I also put jars with water in my unheated GH for heat collection and watering. In summer when rains are rare, i use some of my jars to collect kitchen water to carry to the garden. But recently i was pointed that because my roof is covered with asphalt shingles, i should not use collected water in my veggie beds. Now i am trying to collect rain water for GH and houseplant watering from GH plastic roof. Possible it's time to look for carbon downspout filters to try to catch toxins that can come from asphalt. Any ideas about this?

Adding up the volume of the containers I listed in my original post I came up with 1250+-. What would be the amount I'd like to store versus the amount I am capable of storing with y present investment are two different things.Other than fittings my present outlay is $0.00.Haow many people say say they have the capability of saving that much water with no outlay? With the relatively small collection area I have I can glean about 250 gallons with a 1/4 inch of rain. I'd like to be able to use it for the household but at present am satisfied having it only for the garden. I am on city water and have very little pressure.I use pumps to water because I am tired of the lousy pressure I get every time the lady next door fills her washing machine.(at least that what I think every time I turn on the hose.) All of this is a moot point. I started saving water because of a 4 year drought, the lousy pressure, the cost of metered water from the city. Even if I could only save 50 gallons,that's 50 gallons I am not pulling out of the city's system and paying for treated water that I am going to put on my plants and compost piles. What i am searching for is a way to store the most oamount of water ina given footpring of space. THe only way I can do that in my suburban setting is build vertically.

Excellent question and concerns with many directions to take. Agree with both posters above. SIPS are a good option and its true that there are more hidden condensation and mold concerns by not using current code minimums of exterior insulation or better outside of traditional framing. Your proposed 2x6 wall will perform below current international minimums. Walls always get the most attention but they really only account for 15-35 % of the overall energy performance of a structure. Roof, foundation, windows and air-sealing are other areas ripe for cost-effective improvements. Highly recommend getting an EnergyStar certification for third party verification of basic levels of energy performance and build a home that meets international code standards, even if the majority of your market isn't bothering to. There's probably good financial payback for getting a HERS score 50 or lower, living there for 5-7 years or more with other benefits like improved resale and better indoor air quality.