How to Winterise and Drain Down a Static Caravan (Step-by-Step Guide)

As the holiday season winds down and the first cold nights arrive, draining down your static caravan is the most important job on your maintenance list.

When temperatures drop below freezing, water left in pipes, showers, or boilers will freeze and expand. That expansion splits plastic fittings and cracks copper pipes. When the water turns back on in spring, the result is flooded floorboards and thousands of pounds in repairs. In fact, frost damage causes more insurance claims for static caravan owners than almost anything else.

Here is a practical, step-by-step guide to draining down your holiday home, keeping winter damp away, and preparing your caravan for the off-season.

Why you have to drain down

Static caravan pipework runs beneath floors and inside exterior wall cavities. Without constant heating, an empty caravan drops to outdoor temperatures very quickly.

• Frozen water expands by around 9%, which easily splits plastic joints and cracks brass shower mixer valves.
• Boiler heat exchangers hold water and will crack if frozen, which usually means replacing the whole boiler.
• Most caravan insurance policies state that you must drain down your caravan between October and March if it sits empty for more than 48 hours. If you do not drain down, your insurer may refuse your claim for winter water damage.

Step-by-step drain-down procedure

Set aside about an hour to do this properly. Follow these steps in order:

1. Turn off the main water supply

Find the external stopcock for your pitch, usually located underneath the caravan or in an access box in the ground outside. Turn it off fully. Disconnect your garden hose or water inlet pipe so no residual pressure remains.

2. Open the drain valves underneath

Go underneath the caravan and open the drain-down valves. These are brass or plastic taps located at the lowest points of the chassis pipe run, often colour-coded for hot and cold water. Let the water run out onto the ground or drainage channel.

3. Open all taps and showers inside

Go inside and open every tap fully. Put mixer taps in the central position so both hot and cold lines drain. Unscrew the shower head and hose, let any trapped water run out of the mixer valve, and leave the hose lying flat on the shower tray floor.

4. Drain the boiler

Check the manual for your specific boiler or water heater. Most combi boilers have a small brass drain plug or lever. Turn off the gas and electricity supply to the boiler before opening this drain valve.

5. Clear the toilets and traps

Flush the toilets and hold the handle down to empty the cistern. Sponge out any water sitting in the bottom of the tank. Pour a cup of non-toxic plumbing anti-freeze or a strong salt solution into the toilet bowl and sink U-bends to stop the water trap from freezing and cracking the ceramic.

6. Drain appliances

If you have a washing machine or dishwasher, run a quick drain spin or unscrew the filter cap at the bottom to let standing water out of the pump.

Preventing damp while the caravan is closed

Once the water is off, spend half an hour protecting your soft furnishings and interior from winter damp:

• Stand mattresses on their long edge away from exterior walls so air can circulate around both sides.
• Defrost and clean the fridge-freezer, and wedge the doors open so mildew cannot build up inside.
• Leave internal doors, wardrobes, and kitchen cupboards open so air moves freely between rooms.
• Place salt moisture traps or dehumidifier crystals in the lounge and bedrooms to pull moisture out of the air.
• Never tape over or block floor and wall ventilation grilles. Fresh airflow is your main defence against condensation and mould.

End-of-season checklist

Run through this list before you lock up:

• [ ] External stopcock turned off
• [ ] Under-chassis drain valves opened
• [ ] All interior taps and mixer valves open in central position
• [ ] Shower head unscrewed and hose laid flat
• [ ] Toilet cisterns sponged dry and anti-freeze poured into traps
• [ ] Boiler drained according to manual instructions
• [ ] Gas bottles turned off at the valve
• [ ] Electricity switched off at the consumer unit
• [ ] Fridge defrosted, wiped clean, and doors propped open
• [ ] Mattresses and seat cushions propped up
• [ ] Perishable food removed
• [ ] All windows, roof vents, and doors securely locked

Park drain-down services

If you would rather not do this yourself, our park maintenance teams offer an annual drain-down and reconnect service. Our team drains the system, blows out the lines with compressed air to clear stubborn water pockets, and checks the plumbing before turning it back on in the spring. Speak to park reception to book a slot before the season ends.