Greywater systems can save a lot of water, but having one installed professionally can be costly. Fortunately, you can significantly lower your greywater system costs by installing it yourself. So how do you do it?
To build a DIY greywater system for your home, install a diverter valve and a pipe to divert water from your washing machine through a filter. Next, add plumbing from the filter to a storage tank, put a valve with a spigot on the tank, and choose a greywater dispensing method.
Throughout this article, I’ll explain how you can make a DIY greywater system for your home. I’ll also provide you with several alternative methods, from dispensing options to filters.
1. Install a Diverter Valve and Pipes
According to Green Optimistic, the best way to make a DIY greywater system is to add a diverter valve after the source.
For example, suppose you’re using the greywater from your laundry machine. In that case, you want a diverter valve at the first 90-degree angle after the outlet.
To set it up, follow these instructions:
- Turn off the water supply to the washing room.
- Place the T-shaped diverter valve to split the water leaving the laundry machine.
- Open the valve toward the normal direction of water flow to block the open end.
- Connect a pipe to the closed end of the diverter valve (this will be the direction the greywater flows).
- Add pipes until you get the water line out of the house (some people prefer going through the wall, while others bring the plumbing underground).
Keep these tips in mind at the start of the greywater plumbing process:
- Always use the same plumbing material (copper, PVC, etc.) already in the laundry room.
- Stick to the same dimensions to prevent the plumbing from cavitating or reducing in pressure.
For demonstration, let’s say you’re installing the QWORK 3-Way Brass Diverter Valve. The valve handles up to 600 PSI, far more than greywater systems ever reach. That’s good peace of mind.
The valve comes with one inlet and two outlets.
Ideally, you can connect the inlet to the existing water outlet, then one of the outlets to the water outlet left behind after cutting the plumbing. The second inlet would connect to the greywater line.
2. Use Filtration To Remove Particles
You should only have a greywater system with filtration, especially if you’re getting greywater from sinks that deal with food particles.
Without a filter, you’ll have to let the water settle so the dense particles can fall to the bottom of the tank and allow you to use the greywater. That’s time-consuming and kind of gross!
You have many ways to filter the water flowing through your greywater system, so let’s review your options.
- Crushed charcoal. Crushed charcoal can remove almost all particles from the water. So not only is it easy to maintain, but it also doesn’t develop mold and mildew.
- Filtration sand. This is often used in swimming pools and water treatment facilities, but it’s perfect for DIY greywater systems.
- Dense filtration foam. This system requires filter containers from which you open and remove the foam. It’s common in professional greywater systems but requires more maintenance due to degradation.
The filter should go after the diverter valve and before the storage tank or water outlet. This ensures all the water moves through the filter, removing as much debris as possible.
Using a spigot for your greywater system, you could add a mesh filter over each water outlet.
3. Add Plumbing to a Storage Tank
After adding the filtration system, use similar plumbing to what’s in your laundry room to bring the filtered greywater into a storage tank.
Storage tanks let you keep several gallons of water without flooding your yard. However, some people skip storage tanks in favor of trickling systems.
If you prefer this method, lay a long pipe along your garden and poke holes every 18 inches (46 centimeters).
Your storage tank should be airtight and watertight. Consider using a rain collection barrel.
Rain barrels already have spigots attached, saving time and money. On top of that, rain collection barrels often hold 40 or more gallons of greywater.
Follow these guidelines for this step of the process:
- Use a hole saw with the same dimensions as the plumbing for your greywater system (we’ll stick with ¾-inch plumbing for this example).
- Drill the hole into the top of the water storage tank.
- Place a ¾-inch rubber grommet into the hole to prevent unwanted damage and leaks.
- Slide the pipe through the grommet to ensure a secure fit.
- Open the diverter valve at the start of the greywater system in your laundry room (this will let the greywater flow through the plumbing, filter, and water storage tank when you use the washing machine).
4. Place a Valve on the Water Tank
Much like the previous step, you should use a hole saw to drill a hole into the storage tank.
Next, attach a ¾-inch threaded fitting with a silicone sealant to prevent it from leaking. You can twist a spigot into the threaded fitting, then add a garden hose, bucket, or any other greywater dispensing solution.
Make sure the valve is as low on the tank as possible. It’ll only be able to drain anything above it.
You can elevate the tank on a cement pad or something similar to increase the pressure with which the water drains. Some people prefer water pumps to drive water to the spigot, though.
5. Choose Your Greywater Dispensing Method
There are plenty of ways to dispense your greywater. Here’s a quick overview of the most common ones:
- Drip systems. Connect a series of ¾-inch PVC pipes or a garden hose to the spigot on the water storage tank and poke a ⅛-inch hole every 18 inches (46 cm) on the hose or pipe. When you open the spigot, the water will slowly trickle into the soil in each hole
- Spigot into a bucket: Open the spigot on the water tank, dump the water in a watering can or a five-gallon bucket, and use the water as desired. This is the simplest and most common way of dispensing greywater.
- Plumbed into the sprinkler system: Most plumbing systems use ¾-inch PVC. Cut the pipe, put a T-valve into it, and connect the open end to the greywater tank. Then, every time you turn on your sprinklers, it pulls water from the DIY greywater system.
- Attached to a garden hose: Connect the hose to your water storage tank’s spigot and spray it wherever you need it. This is a common method for those who prefer quick dispensing. Still, you can always remove the hose and switch to the bucket method mentioned above.
Never tilt your greywater tank to get more water out of it. This can break the plumbing or damage the tank!
Review our guide if you have any other home greywater system questions. Choosing the right plumbing can make a world of difference, so it’s worth researching everything beforehand!
DIY greywater systems are convenient, affordable, and eco-friendly. They’re one of the most effective ways to save water 一 some claims cite water savings as high as 40 percent.
Choose the right greywater to avoid food particles, feces, and other contaminants.
The Tiny Life: Simple Greywater Systems For Your Home | The Green Optimist: DIY: How to Build a Greywater Recycling System in 3 Steps | Climate Biz: How To Build A DIY Greywater System (Complete Guide)