Updated: Nov 6, 2018
How will you get one of the most important necessities of life....water. Because North Carolina has a fairly good rainfall each year (averages 43" per year) we were able to use the roof of the house to do a rainwater collection system.
This system has several components to consider while designing the home.
*First the roofing material. We would have really liked a natural dirt roof but it just wasn't the most feasible for us (we'll construct our Sauna with a natural dirt roof). So we selected an all metal roof giving us the best surface for rainwater harvesting. Installation and cost was reasonably priced and metal roofs have a long life span with little maintenance.
*Second how to obtain safe potable (drinking) water. Rainwater is more acidic than tap or well water. Also, after a fresh rainfall will loosen the debris off roof rendering it not suitable for potable water. We did a lot of research on how to get safe potable water. An excellent source directed us to a very reputable company in Georgia...Rainwater Harvesting. We highly recommend this company. Again you need to know how much water you believe you will consume daily and how much rainfall you'll average per month or year. These two factors are critical to design the right size system.
*Third is where to locate your cistern/water tank, material composition of tank and whether you want it above ground or buried in the ground. Again because North Carolina isn't what we call a COLD climate meaning it has fewer back to back days of really below freezing weather we choose an above ground tank . This is important because temperature will determine size and tank placement.....which in turn affects the pricing of a system. Fortunately, we were able to locate the tank within 20 feet from the roof. While we aren't yet finished enclosing the tank building all the important components have already been installed just not hooked up to house yet.
*Fourth consideration was how to sanitize the water. We should note here that when the initial rainwater comes off the roof and flows down toward the tank intake there is a "pre-flush tube" that catches most of the debris before entering the tank. This is part of the Rainwater Harvesting design and it works great and easy to maintain.
Then once we determined the rainfall and best guessed our daily water needs Rainwater Harvesting helped us with the correct size of system which included the filtration design. We have 3 very large filters with varying filter sizes with final Ultraviolet pass through prior to entering the Tankless on demand propane heated water system then into the house.
AND just for fun and because it's really great to have an outdoor shower we built one in the back area of the tank storage building. It is a cedar enclosed outdoor shower using the tank storage north wall (pictures later). Can't wait to use it. AND yes it will be heated....see in another area how we'll do that. Here's a peek....
NOTE: Off grid means you need a safe and sustainable way to collect your "greywater". This is a discussion for later but we did design the EcoHouse for greywater collection.