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Solar Water Heater

Use the space on your roof to generate hot water for your home. You can use it to build your own shower or for washing your laundry or dishes.

Done in 120 minutes
Skill level medium

⚠ Caution! Please note that this solar shower does not have a temperature regulator. Be cautious as the water can become extremely hot under direct sunlight. Use with care to avoid burns or scalds.

Published under CC:BY-SA by

RWTH Aachen University - Institute of Landscape Architecture

Authors · Amelie Schmitz, Max Schröder, Merle Yilmaz

What you need

The tub and the fabric shown on the picture are to create a shower cabin. Find the instruction for it here.

How you make it

Cut out a section from two wooden strips

Ensure that the cut-out corner is large enough for the hose to fit through the hole, minimizing the escape of warm air. Cut the corners on the shorter wooden strips to guide the hose into the frame later.

Nail or screw the wooden strips together to form a strong frame

Make sure the corners are well connected.

Nail the wooden board to the frame

Pass the hose through the frame and fold it into a flat coil

Be careful not to create any kinks, as they can block the water flow.

Secure the hose on the wooden board.

By using a wooden piece to hold it in place, you prevent the hose from losing its shape.

Close the top of the frame

Use transparent film. You can use various transparent materials such as foils, Plexiglas, or similar. Ensure it is sealed as airtight as possible.

Mark the size of the water hose reparator on the lid of the drainpipe

The mark should be drawn based on the diameter of the element, which will be inserted through the hole.

Drill around the edge of the mark

Try to drill within the marking. If in doubt, make the hole a little smaller and enlarge it later.

Remove the part from the lid

This is roughly how it should look after drilling. If the part cannot be removed from the lid, drill a few more holes.

File the hole if needed to fit the water hose reparator

Fit the water hose reparator through the hole in the lid of the drain pipe

If the hole in the lid is big enough, put the inner part of the reparator through the hole.

Connect the water hose with the lid

Put the hose on the inner part of the connector and screw on the outer part firmly to ensure a secure connection and prevent water from leaking.

Connect the water hose with the bottle lid

For the outlet, find a bottle cap that can be opened and closed, like a detergent or shampoo lid. If the hose diameter doesn’t fit the cap, use duct tape to adjust it for a snug fit, as shown in the picture. Now your water heater is ready.

Put the Water Heater on the roof

Ensure the solar water heater is installed with a slight slope to allow smooth water flow. Place the drainpipe above the hose spiral. If your roof doesn’t have a slope, you can create one using simple methods like sandbags. This will help optimize the efficiency of the water heater.

Fill the drainpipe with water through the top opening

Keep the end of the hose open to allow the air to escape, ensuring smooth water flow through the hose. Ensure that your roof can bear the weight of the solar water heater, as it will become heavy with water. If your roof is not sturdy enough, consider adding an additional substructure for support. Safety is crucial!

To bring the warm water inside your home, lead the hose through gaps in the roof

The wavy shape of the zinc roof’s material should allow for this. Ensure a secure and watertight connection to avoid any leaks.

Enjoy your hot water!

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