Take the water that comes from your roof.
Function and use of a rainwater cistern
The use of rainwater is becoming increasingly important. Drinking water is not only expensive, it is ecologically too precious to use it for purposes other than for drinking and for personal hygiene. The principle of a rainwater harvesting system is simple.
- When it rains, a large amount of water hits the roof of your house. This collects in the gutter and runs into a downpipe. Without a gathering at the house of this water flows through the sewage waste in rivers or streams.
- If a rainwater tank connected, cleans a rainwater filter this water. It flows into the lower portion of the cistern. Thus there are no turbulences, sheets or curved lines are needed. Thus, the dirt settles to the bottom.
- The collector is also connected to the sewage system of the house. About an overflow, the water flows from the tank into the waste water when it is filled. Depending on the surface, the water can seep into a percolation basin in the ground.
- The tank is fitted a pump to remove the water. As above is the cleanest water, the water flows through a float to the pump. So you always take the water, which is located at the top of the cistern.
- If the water used in the garden only for casting, this pump is sufficient. If you want to use the water for flushing the toilet and washing machine, you need a house waterworks. This ensures a uniform pressure in the domestic water pipe.
The use of rainwater is useful for watering of plants, for flushing toilets and for washing in a washing machine. It is also due to brushing. The use of rain water for bathing, showering or in the dishwasher is not possible for reasons of hygiene.
Costs and benefits of rainwater harvesting systems
The costs for water and waste water costs rise. In the long run makes it more sense to use rainwater. One cubic meter of water cost, together with the fee for the waste water depending on the region in 2014 up to five euros, significant cost increases are expected.
- Rain barrels are small rain collector. They cost less than a hundred euros. However, they are only suitable for the casting of potted plants and individual beds. A barrel of 200 liters costs about 30 euros. It pays for itself if you have saved six cubic meters of water with it. The 30 panels of the barrel.
- If you want to collect more water, you need to set up a more complex calculation: Firstly, the required amount of water plays a role, on the other hand the potential yield of rainwater. The need depends on the size of the irrigated garden and on the number of people, if you want to use toilet and laundry with rainwater. The yield depends on the roof, the flashing of the roof and the region in which the house stands. Use a calculation tool from the Internet to determine the right size of the cistern.
- A rough estimate, you need 3,000 to 4,000 liters of storage volume in a four-person household. The square meter of roof you can fill between 30 to 50 liters of storage. With a roof area of 50 square meters, is worthwhile only a plant with more than 2,500 liters, although you need more water. Does your roof 150 square meters, you can fill a memory 4500-7500 liters. Such a great memory does not make sense if you do not need the water.
- Even a rainwater cistern at the optimum size gets paid only long term. A walk-in plastic tank with the art equipment for domestic water use in the house will cost about 2,000 euros, with a volume of 4,000 liters. These costs are amortized only after years. You must save 400 cubic meters of water, before the investment is worthwhile. This is usually only after ten years of the case. As the most expensive on the equipment, the technology, the cost of concrete cisterns are only slightly lower.
Installation of the system
there is a long way from the planning to the connection of the system.
- Determine based on your water needs and the possible yield the size of the tank. If you know this, you consider whether you are at the underground tank is possible.
- Check what type tank installing the best. For hard floors or a high groundwater level is a flat tank which requires only a small excavation depth, meaningful. Opt for a system that suits the income, the needs and the local conditions.
- Prepare the connections for the tank. You need three lines must have a slope of at least one percent each. One line goes from the downspout to the tank, the overflow to the sewer line and the tank for the hot water system of your home.
- If you do not have a separate hot water system in the house, install the cables from the planned input terminal of rainwater into the house to all toilets and washing machine.
- Insert the pit and the trenches in which the lines are intended to be, from. You need in the pit of movement. You should be a meter wider than the tank in all directions.
- Let the pit digging of a civil engineering company. With bucket and shovel it takes too long and is too cumbersome. This is also the ground condense, so that the tank has a firm footing.
- Once the pit is prepared so the tank can into the ground. Orders him to an appointment, shortly after completion of the pit. The company should put the tank into the pit. Unless you have chosen a concrete cistern, must be sealed with sealing compound this now.
- Lay the cables in the trenches and connect these. Install the pump and install a water level indicator.
- The construction company will fill the pit with rounded gravel with a maximum grain size of 8/16. Cover the gravel layer with fleece before applying ten centimeters of topsoil and plant the grass. Alternatively, you can concrete the area or cover with stones.
The planning and construction of a large rainwater cistern is costly. Ask if necessary a professional for help to determine the optimal size.