Motorhome Winterisation – How to Prepare Your Campervan for the Winter

Introduction

As the colder months approach, motorhome winterisation is essential to keep your vehicle safe and in top condition. Whether you’re storing it for winter or planning occasional trips, taking the right steps now prevents damage and costly repairs. In this guide, we’ll walk you through how to winterise a motorhome, covering storage, maintenance, and key preparations.

Download our detailed PDF checklist

1. Storing Your Motorhome

Where you store your motorhome during winter makes a big difference in protecting it from theft and weather damage. You can keep it on your driveway, at a CaSSOA-approved storage site, or even on private land if security is good. No matter where you store it, make sure the site has the following:

• CCTV and alarms for added security.
• High fences and locked gates with individual access keys.
• 24-hour surveillance to deter thieves.
• Level, hard-standing ground to prevent sinking in wet conditions.

Ensure You’re Insured

Many insurance providers offer discounts if you store your motorhome at a CaSSOA site, as these locations have strict security measures. Keeping your motorhome on your driveway is more convenient, but it might make your home a target for thieves. Always check your policy to see if preparing your motorhome for winter storage affects your coverage.

2. Interior Preparation

Preparing your interior as part of motorhome winterisation helps prevent damage, damp, and bad odours. Fortunately, a thorough clean and proper storage will keep everything fresh. Follow these steps to ensure your motorhome stays dry, secure, and ready to use.

Clean Your Motorhome Thoroughly

Dirt, dust, and leftover food can attract rodents, insects, and bacteria if you leave it unattended. A deep clean before winter storage will keep your motorhome fresh and prevent infestations or bad smells. We’d advise focusing on the following key areas:

• Remove all food, crumbs, and perishables from cupboards, drawers, and storage compartments. Even sealed dry goods should be taken out, as pests can chew through packaging.
• Clean the fridge and freezer thoroughly, wiping down surfaces with a mild disinfectant or a mix of water and vinegar. Leave the doors slightly open to allow airflow.
• Vacuum and wipe down all surfaces, including floors, kitchen counters, seating, and hidden spaces like under seats and behind appliances.
• Empty all rubbish bins and check for any leftover wrappers, receipts, or hidden food items.
• Place an open box of baking soda in the fridge to absorb lingering odours.

Remove Valuable Items

Motorhomes can be targets for theft, especially when left unattended for months. Protect your valuable belongings by removing all portable electronics and valuable motorhome appliances before storage. You should:

• Take out TVs, radios, coffee machines, and small kitchen gadgets to prevent theft or condensation damage.
• Store valuables like laptops, cameras, and personal belongings elsewhere to reduce the risk of break-ins.
• If any expensive items must stay inside, store them out of sight in locked cabinets.
• Remove all batteries from clocks, remote controls, alarms, and other small gadgets to prevent leaks and corrosion.
• Store important documents, spare keys, and motorhome manuals in a safe indoor location to prevent loss or damage.

Protect Furnishings

Your motorhome’s fabrics, upholstery, and bedding can become damp and musty if not stored properly. Taking a few simple steps will help protect them over winter. We’d recommend that you:

• Close blinds and curtains to prevent UV damage and fading to upholstery.
• Remove all bedding, pillows, and cushions, or store them in vacuum-sealed bags to protect against moisture.
• Stand cushions upright rather than stacking them to promote airflow and prevent damp spots.
• Wipe down leather or fabric seats with a protective spray to keep them in good condition.
• If storing bedding inside the motorhome, place moisture-absorbing sachets nearby to prevent mildew.

Reduce Moisture and Damp

Damp is one of the biggest problems in motorhomes over winter, leading to mould growth and musty odours. Reducing moisture inside your vehicle will keep it fresh and prevent damage. Here’s how to do so.

• Use dehumidifiers or moisture-absorbing crystals to control condensation.
• If possible, keep heating on low (if connected to power) to prevent extreme temperature drops.
• Ensure all ventilation points remain unblocked to allow airflow and reduce condensation buildup.
• Air out the motorhome periodically by opening windows and doors on dry days.
• Leave cupboard doors slightly open to prevent stale air and allow circulation inside storage areas.

Ensure Gas Bottles are Protected

Gas safety is crucial when storing your motorhome for winter. Taking the right precautions will prevent leaks and ensure a safe, hassle-free startup in spring. In that light, you should:

• Turn off all gas bottles completely before storing your motorhome.
• Disconnect gas cylinders if possible and store them in a well-ventilated area away from direct sunlight.
• Check all gas fittings, hoses, and connections for wear or damage before storage.
• Never leave a gas bottle connected while your motorhome is in storage, as leaks can be dangerous.
• If storing gas bottles indoors, ensure they are upright and secured properly to prevent tipping.

3. Exterior Preparation

Protecting your vehicle’s exterior during motorhome winterisation is just as important as looking after the inside. Exposure to rain, frost, and dirt over winter can cause wear, rust, or damage. Taking the right steps now will keep your motorhome clean, well-maintained, and ready for your next trip.

Give It a Good Clean

A thorough exterior clean before storage helps prevent long-term damage from dirt, grime, and environmental elements. Certain deposits can become harder to remove over time or even cause permanent stains or corrosion. Focus on these key areas:

• Wash the entire motorhome using a mild detergent or specialist cleaner to remove dirt, road grime, and bird droppings.
• Clean awnings, window seals, and wheel wells, as dirt buildup can cause deterioration or mildew if left untouched.
• Dry the vehicle fully after washing to prevent trapped moisture from causing rust or mould growth.
• Apply a protective wax coating to help shield the paint from moisture and UV exposure.
• Keep all windows and vents closed to prevent moisture buildup inside the motorhome.

Use an Insulated Exterior Cover

A high-quality, breathable cover protects your motorhome from harsh weather, dust, and debris during storage. However, the wrong type of cover can cause more harm than good. So, it’s essential to choose carefully.

• Use a purpose-made, breathable motorhome cover to allow airflow and prevent condensation.
• Avoid parking under trees, as sap, bird droppings, and falling branches can damage your motorhome’s paintwork.
• Never use a plastic tarpaulin, as it traps moisture, leading to mould, corrosion, and paint damage.
• Ensure the motorhome is completely dry before covering to avoid sealing in moisture.
• Check for any holes or tears in the cover and repair them before winter storage.

Repair Damage

Small cracks, leaks, or chips may seem minor, but winter weather can quickly make them worse. Addressing these issues before storage prevents expensive repairs later on. Here’s what to focus on:

• Inspect the motorhome’s exterior for cracks, leaks, or gaps and seal them properly before winter.
• Check roof seals, window seals, and door edges for any damage that could let in moisture.
• Protect boiler and fridge vents with vent covers to keep insects, dirt, and moisture from getting inside.
• Look for paint chips or exposed metal, as these areas can quickly develop rust in damp conditions.
• Touch up small paint chips with sealant or rust-resistant paint to prevent corrosion.

4. Protect the Leisure & Vehicle Battery

Your motorhome’s battery needs proper care to stay charged and in good condition over winter. Long periods without use can lead to power loss or permanent damage. Taking a few simple steps now during the motorhome winterisation process will ensure your battery is ready when you need it.

Check Voltage

Batteries naturally lose charge over time, especially in cold weather. Ensuring your battery is fully charged before storage helps prevent damage and costly replacements. Keep an eye on voltage levels by following these steps:

• Charge the battery fully before storing your motorhome to maintain its lifespan.
• A low-voltage battery (below 12.4V) may fail over winter, leaving you with a dead battery in spring.
• Check voltage levels regularly if storing your motorhome for an extended period.
• Use a multimeter to test battery voltage and recharge it when needed.
• If the voltage drops significantly, recharge the battery before permanent damage occurs.

Disconnect Battery / Switch on Isolation

Leaving your battery connected while in storage can result in slow discharge, even if nothing is actively drawing power. Disconnecting it or using an isolation switch will help preserve battery life and prevent unnecessary wear.

Here’s what you should do:

• Disconnect the battery if your motorhome will be unused for months to prevent power drain.
• Use an isolation switch if you prefer to keep the battery connected but want to prevent slow discharge.
• If you’re using solar panels, check if they provide a trickle charge to maintain battery levels.
• For motorhomes with multiple batteries, ensure each one is properly maintained during storage.
• Store the battery in a cool, dry place if removing it from the vehicle.

 

5. Clean and Drain Your Water System

Another important part of motorhome winterisation involves draining your motorhome’s water system, which prevents the pipes from freezing and bursting during winter. If water remains inside, freezing temperatures can cause expansion and lead to costly damage. Be sure to follow these steps to guarantee your water system is fully winter-ready.

Find Your Drain

Locating your drain-down valve is the first step in properly winterising your water system. This valve allows you to empty the water system completely, reducing the risk of frozen pipes and internal damage. Make sure to:

• Find your drain-down valve, usually located near the water heater or boiler. If you’re unsure, check your motorhome manual or contact the manufacturer for guidance.
• Ensure the drain valve is fully open before starting the draining process.
• Park on level ground to allow water to drain out evenly.

Drain Tanks

Draining both your fresh and waste water tanks is crucial to prevent trapped water from freezing inside the system. Even small amounts of leftover water can expand and cause serious damage. Therefore, you should:

• Completely empty the fresh and waste water tanks before winter storage.
• Open all taps and leave them in the mid-position to allow both hot and cold pipes to drain.
• Let all water fully drain out before closing the valves again.
• If possible, tilt the motorhome slightly to help remaining water escape.

Clean Water Tanks

Cleaning your water tanks before storage helps remove bacteria, scale, and lingering odours. This ensures your motorhome’s water system remains fresh and hygienic when you use it again. To properly clean the tank, you should:

• Flush out water tanks with a specialist cleaning solution to remove bacteria and scale buildup.
• Rinse thoroughly to ensure no residue is left behind.
• Leave the tanks vented slightly to allow airflow and prevent musty smells.
• Use a food-safe sanitiser to prevent bacterial growth inside the tanks.

Clean Water Tanks

Drain Cleaning Solution

Flush Pipes

Even after draining, small amounts of water may remain trapped in the pipes. Flushing the system completely removes any residual water and prevents ice formation inside the plumbing. Be sure to:

• Turn on every tap until no water remains in the pipes.
• Drain the shower hose by placing it in the shower tray, allowing all water to escape.
• Empty your motorhome’s external shower, if it has one.
• Blow compressed air through the pipes if you want to ensure all moisture is gone.

Flush Waste

Your motorhome’s waste system also needs to be cleaned before storage to prevent odours and bacteria buildup. Properly winterising your toilet cassette and waste tank avoids nasty surprises in spring. Make sure to:

• Empty and clean your toilet cassette with a specialist cassette cleaner.
• Pour a small amount of antifreeze into the waste tank if temperatures are expected to drop significantly.
• Place plugs in sinks and showers to stop bad smells or insects entering through the drains.
• Wipe down the toilet bowl and cassette seal to prevent mould or bacteria growth.

Add Antifreeze

If your motorhome has a wet heating system, ensuring the correct antifreeze concentration is crucial. This step prevents frozen heating pipes and costly repairs. Remember to:

• Check that your wet heating system has the correct antifreeze mix for winter conditions.
• Follow the manufacturer’s guidelines for the right antifreeze concentration.
• Run the heating system briefly after adding antifreeze to ensure it circulates through the pipes.

6. Check Vehicle Fluids

Checking your vehicle fluids ensures your motorhome stays in top condition over winter. Low fluid levels or incorrect mixtures can cause engine issues, corrosion, or freezing problems. Take time to check the following before storing your motorhome.

Coolant / Antifreeze

Your engine coolant, also known as antifreeze, plays a crucial role in preventing freezing, overheating, and corrosion. Without the correct mix, your engine components could freeze or become damaged, leading to expensive repairs. Here’s some advice:

• Ensure your engine coolant is topped up and correctly mixed for winter storage.
• A 50:50 mix of coolant and water typically protects against freezing down to -10°C or lower.
• Use an antifreeze tester from a local auto store to check the mixture if unsure.
• If the coolant looks cloudy or dirty, consider replacing it before winter storage.
• Never dilute coolant with plain water in winter, as it weakens freeze protection.

Screenwash

Cold weather can make windscreens more prone to dirt, ice, and reduced visibility. Using the wrong screenwash mixture can lead to frozen washer fluid, making it impossible to clean your windscreen when driving in cold conditions. Here’s how to do it properly:

• Fill your windscreen washer tank with a winter-grade screenwash to prevent freezing.
• Check the dilution ratio to ensure protection against sub-zero temperatures.
• Choose a concentrated screenwash formula for extra freeze protection in colder climates.
• Run the washer system briefly after filling to ensure the fluid is circulated through the nozzles.
• Avoid using plain water, as it can freeze and damage the washer system.

Useful Links:

• https://www.halfords.com/motoring/engine-oils-fluids/antifreeze/halfords-antifreeze-tester-meg
• https://www.halfords.com/workshop-tools/tools/hand-tools/laser-antifreeze-tester

7. Tyres

Your tyres endure harsh conditions in winter, so taking extra care during storage helps maintain their lifespan. Cold weather, weight pressure, and UV exposure can all contribute to tyre damage. Follow these steps to keep your tyres in good shape.

Check Tyre Pressure

Proper tyre pressure is essential for preventing deflation, uneven wear, and flat spots. Cold temperatures naturally cause tyres to lose pressure, which can make them unsafe to drive on when you use your motorhome again. To avoid this, make sure to:

• Inflate your tyres to the manufacturer’s recommended pressure before storage.
• Cold weather can cause pressure loss, so ensure your tyres are topped up before long-term storage.
• Check tyre pressure periodically if your motorhome is stored for several months.
• Use a digital tyre pressure gauge to monitor levels properly.

Cover Wheels

Tyres are vulnerable to UV exposure, frost, and moisture, which can cause cracking, hardening, or early wear. Using wheel covers is a simple but effective way to protect them. Here’s our advice:

• Use high-quality wheel covers to shield tyres from UV rays and frost.
• Sunlight can dry out rubber and cause cracking, shortening tyre lifespan.
• Covers also protect metal components, such as wheel nuts, from rust.
• If you don’t have wheel covers, park on rubber mats or wooden planks to reduce direct contact with the cold ground.
• Ensure covers fit snugly to prevent them from blowing away in strong winds.

Lift Weight Off Tyres

When a motorhome sits in one position for too long, the weight pressing down on the tyres can create flat spots. These can make the ride feel bumpy and uncomfortable, and in extreme cases, the tyres may need replacing. To avoid this:

• If possible, use axle stands or levelling jacks to take weight off the tyres.
• If lifting the motorhome isn’t possible, rotate its position every few weeks to distribute pressure evenly.
• Drive the motorhome forward or backward slightly to change the contact points on the tyres.
• If using ramps, choose ones with a concave surface to help maintain the tyre’s round shape.

Useful Links:
https://towsure.com/tyre-savers
http://www.fiammastore.com/Fiamma-Levellers-for-caravans-and-motorhomes/Fiamma-Wheel-Saver

Winter Storage Checklist

We’ve covered a lot of ground so far! All the points we’ve made should be kept in mind, but some are more crucial than others. So, let’s revisit the most important winter storage tips in a checklist:

1. Storage & Security: Choose a secure storage location (home, CaSSOA site, or private land. Install wheel clamps, locks, and an alarm for extra protection. Finally, check insurance coverage for winter storage.
2. Interior Preparation: Remove food, valuables, and electronics to prevent theft and damage. In addition, clean thoroughly and use moisture absorbers to reduce dampness. You can also use blinds and curtains to protect furnishings.
3. Exterior Preparation: Wash and wax your motorhome to protect the paintwork. You should also use a breathable cover if you’re storing your vehicle outside. Finally, be sure to check for leaks or damaged seals (and repair them, if necessary).
4. Battery & Electrical System: Remember to fully charge and disconnect the battery or use an isolator. If you use solar panels, make sure they provide a trickle charge.
5. Water System: Drain all tanks, pipes, and the toilet cassette. You should also clean and flush the water system before storage. If your motorhome has a wet heating system, don’t forget to add antifreeze.
6. Tyres & Fluids: Inflate tyres to the correct pressure. If you can’t move the vehicle regularly, be sure to use wheel covers. Finally, top up coolant, antifreeze, and screenwash.

Conclusion

Now you know just how to prepare your motorhome for winter storage, and how doing so protects it from damage, damp, and costly repairs. By following these steps, you’ll keep it safe, dry, and ready for your next adventure. Download our detailed PDF checklist to ensure you don’t miss a step and make winter storage easy.