When winter hits, an RV that sits unused all season is exposed everywhere water can get in. Most guides only talk about frozen pipes, but your plumbing is only part of the story. For example, your RV roof carries the same amount of risk. Seams, vents, skylights, and old seals are prime spots for water to sneak in over a long, cold winter, and a leak you find in spring costs a lot more than the few minutes it takes to check things now.
Your pipes are still important, too. Once temperatures drop to around 35°F to 45°F (2°C to 6°C ), the water sitting in your RV's lines and pipes can freeze. Frozen water expands, and that can crack your pipes, which means a repair bill and a headache come spring. Winterize every year as soon as temperatures start to fall, and you'll skip that problem entirely.
This guide covers winterizing your RV from top to bottom: water system, roof, battery, and undercarriage, so nothing surprises you when storage season ends.
What You'll Need to Winterize Your RV
Winterizing your RV touches a few different systems, so gather materials by area. Here's what you'll need and why, broken into four sections that match the steps below.
Water & Plumbing System
Antifreeze (RV-specific, non-toxic), 2 to 3 gallons: protects your pipes and tanks from freezing and cracking.
Water heater bypass kit: keeps antifreeze out of your water heater so you're not filling a tank you don't need to protect.
Water pump converter kit: lets your pump pull antifreeze straight from the jug instead of your fresh tank.
Tank cleaning wand: flushes gray and black tanks clean so nothing sits and smells all winter.
Socket wrench or drill: removes low-point drain plugs so your tanks empty completely.
Roof & Exterior Seals
Flashlight: helps you spot cracks, lifting seams, and gaps around vents that daylight glare can hide.
Roof sealant or repair tape: patches small cracks now instead of letting them turn into a leak. Products to achieve this: RV Lap Sealant Product and RV Seam Tape Product
Soft-bristle broom: clears leaves and debris so you can actually see what you're inspecting.
RV Roof Cleaner: removes dirt, grime, and chalky residue so any sealant you apply actually bonds to the roof instead of sitting on top of buildup.
RV Roof Primer and Coating: use this if you're planning on sealing the entire RV roof, not just vents, seams, and edges.
Battery & Power
Battery disconnect or trickle charger/maintainer: keeps your battery from draining dead or corroding while it sits.
Terminal cleaner or wire brush: clears corrosion so your battery makes a clean connection when you reconnect it.
Undercarriage & Tires
Tire pressure gauge: correct pressure prevents flat-spotting while your RV sits still for months.
Tire covers: blocks the UV exposure that dries out and cracks rubber over a long storage season.
Leveling blocks or jack stands (optional): takes weight off your tires for extra-long storage periods.
How to Winterize Your RV
Work through these in order, section by section.
Steps to Winterize Your Water & Plumbing System
Step 1: Remove Inline Water Filters
Antifreeze will be running through your water system, so pull any inline filters first. This keeps them clean and ready for spring, and it's a good time to replace them if they're due.
Step 2: Flush Your Gray and Black Water Tanks
Head to your local dump station and empty both tanks completely. Give yourself extra time here. Once they're empty, flush each tank thoroughly with a built-in flushing system or a cleaning wand.
Step 3: Empty the Water Heater
Turn off the heat source and let the water cool completely. Open the pressure release valve with a socket wrench to drain it, then turn the water pressure back on briefly to flush out any sediment.
Step 4: Bypass the Water Heater
If your RV has a built-in bypass, activate it now, before you add antifreeze. No built-in bypass? Get a bypass kit installed before winter hits.
Step 5: Empty the Low Point and Fresh Tank Drains
Turn the water pressure down, remove the drain plugs, and let everything empty out. Close the faucets and low point drains once you're done.
Step 6: Connect the System to Antifreeze
Follow your manufacturer's specs here. Most RVs use a water pump converter kit or the existing water intake line to pull antifreeze into the system.
Step 7: Open Every Valve and Faucet
Start at the faucet closest to your water pump and work outward, hot and cold, until antifreeze runs through. Don't skip the shower. Every faucet and valve needs to see antifreeze.
Step 8: Flush the Toilet
Flush until antifreeze appears. This protects the toilet and the septic system through winter.
Step 9: Pour Antifreeze Down the Drains
Pour one to two cups of antifreeze down every drain in your RV to protect the lines from freezing.
Step 10: Final Preparations
Double-check your water heater is off and every faucet is closed. Your water system is ready for storage.
Winterize Your Roof & Exterior Seals
Walk the full roof with your flashlight (or have someone spot you from the ground). Check every seam, vent, and skylight for cracking, lifting, or gaps. We break down exactly what to look for in the next section, so keep reading before you put the ladder away.
Winterize Your Battery & Power
Disconnect your battery, or connect a trickle charger or maintainer if you'd rather leave it in place. Clean the terminals with a wire brush first so you get a solid connection when you hook it back up in spring.
Winterize Your Undercarriage & Tires
Check tire pressure and inflate to the manufacturer's spec. Cover the tires to block UV exposure, and set up leveling blocks or jack stands if your RV is going to sit for more than a few months.
Inspect and Seal Your Roof Before Storage
Your roof takes the most abuse of any part of your RV, and it's where water can easily get in during storage. Sun, rain, and temperature swings work on your seams, vents, skylights, and exterior seals all season long. By fall, those spots can be ready to fail, especially if it's been a few years since they've been inspected.
Here's the visual check to run before your RV goes into storage (or grab our RV Winterization and Roof Inspection Checklist) and take it out to the roof with you):
- Look along every roof seam for cracking, bubbling, or lifting.
- Check around vents and skylights for gaps or separated caulk.
- Run your hand along the edges. Chalky or crumbly sealant means it's past its best.
- Look for soft spots on the roof surface, which can mean water's already gotten in.
Catching these issues now, before your RV sits through months of rain, snow, and freeze-thaw cycles, is a lot cheaper than dealing with water damage later. A small crack you seal in fall is a five-minute fix. That same crack left through winter can turn into soaked insulation or warped walls.
If you do find cracked seams or worn seals, sealing them before storage is a straightforward DIY job. We'll get into product recommendations and exactly how to do it in a future post. For now, the goal is simple: know what shape your roof's in before you park it for the season.
Additional Tips for Winterizing Your RV
While the steps above cover the big systems, a few extra tasks round out your storage prep:
Clean the interior. Leftover food or trash attracts pests fast, and a mouse problem is harder to deal with than an extra ten minutes with a vacuum. Wipe down counters and check under seat cushions too.
Cover your RV. A breathable cover protects it from sun, snow, and debris without trapping moisture underneath. Skip the tarp. It holds moisture against the surface instead of letting it breathe.
Check for pests. Look for droppings, chew marks, or nesting material anywhere food or fabric is stored. A few dryer sheets or a pest repellent tucked in cabinets goes a long way for the cost.
Prop open the fridge and freezer. Empty them out and leave the doors cracked so air can circulate. A fridge that's emptied but sealed shut traps moisture inside, and that's a fast track to mold.
Turn off your propane. Shut off the tanks at the source before storage. It's a simple step that removes a fire risk while your RV sits unused.
Want a simple reference for all of this? Get a checklist to tack up in your RV, including a full roof inspection checklist, so nothing gets missed before storage. Get it sent to your inbox with the pop-up.
FAQ: Quick Answers About RV Winterization
How cold does it need to get before I winterize my RV?
Once nighttime temperatures drop to around 35°F to 45°F (2°C to 6°C ), it's time. Don't wait for a hard freeze. By then the damage may already be done.
Can I still use my RV in winter without winterizing it?
If you're using it regularly and running the furnace to keep the interior above freezing, you might be fine. But if your RV sits unused for more than a few days in freezing temps, drain the water system.
How often should I check my RV roof for damage?
Twice a year is a solid baseline: once before winter storage and once when you pull it back out in spring. If you store your RV outside, add a mid-winter check when weather allows.
What's the difference between winterizing and storage prep?
Winterizing specifically protects your water system and roof from freeze damage. Storage prep is the bigger picture: covering, pest-proofing, battery care, and everything else on this list.
Can I seal my vents and roof seams now and seal the entire roof later?
Yes. Spot-sealing cracked seams and vents now protects the areas most likely to leak, and you can do a full roof coat later when you have more time. Don't let small cracks sit unsealed through an entire winter, though. Freeze-thaw cycles can turn a small crack into a bigger repair.
Let's Wrap This Up
Winterizing your RV protects the systems that keep it running, and the roof over your head, literally. Follow the steps above for your water system, roof, battery, and undercarriage, and your RV will be ready to go when storage season ends.
Want a simple reference to tack up in your RV? Download the RV Winterization and Roof Inspection Checklist. It walks you through everything above, plus what to check on that first roof walk.
