How to Repair Soft Spots or Water Damage in an RV Roof
All it takes is a step, and your whole day can be ruined. You might be up on your RV roof inspecting it for leaks, or you might just be cleaning off pine needles and leaves. You take a step, and that's when you notice something just doesn't feel right...
Your roof feels a bit soft or spongy. And immediately, you know you've got a problem that needs your attention ASAP!
You could forget about it. But ignoring that soft spot only means that it's going to get worse. Soft spots on RV roofs are almost always the result of water damage. And if left untreated, that damage can spread, turn into irreparable mold problems, rot out your walls and insulation, and lead to all sorts of structural damage that we're sure you don't want to have to deal with.
And that's why we've put together the following guide on repairing soft spots, before things get out of hand!
You can also check out our ultimate RV roof repair manual for more information on maintaining and repairing your RV roof.
How to Identify Soft Spots or Water Damage in Your Roof
Now, if you've already been up walking on your RV roof, it's easy enough to notice if you've got soft spots.
But you should also keep an eye out for signs of water stains or discoloration, warping or bubbled-up roof panels, which can indicate water damage before soft spots happen.
The same thing goes for the interior of your RV. Water stains, bubbled or peeling wallpaper, panels, or cabinets, and a damp musty odor are all sure-fire signs that moisture is making its way into your cabin.
Sometimes, a bit of caulk, RV sealant tape, or lap sealant is all you need to fix a leak in your RV roof. But once you've found a soft spot, it's usually a tell-tale sign that you've got a more serious problem on your hands.
What Causes Soft Spots in an RV Roof?
Soft spots aren't caused by one-time, overnight leaks. So if you've got a noticeable soft spot, it's usually the result of long-term water intrusion. You might just have a small leak, but if it's not stopped, it can lead to rotten structural wood.
Here are a few of the most common causes of soft spots:
- Longer-term leaks around vents, skylights, AC units, or roof membrane edges and seams
- Dried-out, aged, or cracked sealants
- Manufacturer defects or sloppy DIY jobs from previous owners
- Worn out or poor quality RV roof coatings
- Long-term UV and weather exposure
Ultimately, the older your RV is, the more likely you're going to encounter roof leaks from time to time.
And that's why we strongly encourage you to inspect your RV roof at least twice per year to catch those pesky leaks before they lead to soft spots and structural damage.
For more information on how to properly seal your RV or camper, check out our RV roof sealant guide 2025.
Assessing the Severity: Surface Damage Vs. Structural Rot
The first step in repairing water damage is to assess the damage and find out where water has been getting in. Once you've got the source of your leak figured out, the next step is to find out how deep the damage actually goes.
Keep in mind that not all spongy or soft spots will require a full tear-apart and rebuild. If your roof membrane leak is relatively new, you may be able to get away with a small DIY job, letting the damp materials dry, and then resealing your roof.
Do a bit of digging and find out how far moisture has made its way inside. If you find damp foam or insulation that's not moldy, you might be in luck. Use a dehumidifier or fan to dry the area thoroughly. Then replace your wall or ceiling panels, and reseal your roof.
However, if you've got mold, notice any sort of rot, or if you see any warping, you're most likely looking at a much more intense repair job.
Tools and Materials You’ll Need for Repairing Soft Spots
Have you ever sat down on the toilet to do your, ummm, business, only to realize half-way through that you're out of toilet paper? If you have, you already know the importance of having the right tools on hand.
Here's a quick list of the what you'll likely need to gather before getting started.
Tools
- Hammer
- Screwdrivers
- Crowbar
- Utility knife
Replacement Building Materials
- New plywood
- Foam or insulation
- Plastic or rubber vapor barrier
- Spray adhesive, RV Glue or Adhesive RV sealant tape
- Lap sealant
- Caulk and caulking gun
Personal Protective Equipment (PPE)
- Work gloves
- Safety glasses
- Mask or respirator (important for dealing with mold)
- Tarp or plastic sheeting
If this is your first time attempting an RV roof repair, we recommend purchasing an RV roof repair kit, which include most of the tools and sealants you'll need to get the job done right.
Step-by-Step: How to Fix Soft Spots or Water Damage
The exact process of repairing your RV largely depends on the severity of the damage. But here's a quick breakdown of what the repair process might look like for soft spots and water damage.
Step #1 - Open Up The Damaged Area
First, you'll need to remove any old sealant, caulk or tape, and then cut back your TPO or EPDM roof membrane to access the underlying materials. This can be a tough and intense job. So it's best to prepare yourself ahead of time.
You'll need to cut into or remove the existing layers roof materials. You'll want to remove only as much material as necessary to access the damaged area. So if possible, only remove the affected roof panel or cut around the area you intend to repair.
Be super careful here and only cut through the top layer of roofing material. If you're at all unsure about how to open up your RV roof, it might be best to leave the repair to a professional.
Step #2 - Remove Damaged Materials
Once you're inside, you'll need to remove any materials that have been damaged by water or mold. Insulation, foam, plywood... If it's wet, soggy, or moldy, it needs to go!
When removing damaged materials, just make sure to be careful and not damage any adjacent materials in the process.
Step #3 - Drying Out The Area
Next, you can use fans, heaters, or dehumidifiers to dry out any salvageable materials.
If it's moldy, it's not worth drying out. But if some of the underlying plywood, insulation, or foam seems like it hasn't been affected by water, you might get away with leaving it alone and allowing it to dry.
It's best to give your work area plenty of time to dry. Even with a fan, heater, or dehumidifier, it might take a couple days for the materials to dry out completely.
Step #4 - Replacing Your Building Materials
Moving forward, it's time to replace any of the materials that you've removed.
Fill any gaps or voids with new foam or insulation. Cover it all with a plastic vapor barrier if there was one in the first place. And then cut and fit in new plywood to replace the old.
Lastly, you'll need to replace the vinyl, EPDM, TPO, or metal layers that you've removed in step #1. Make sure to replace everything exactly as it was before you took the roof apart and then seal everything up to ensure your new roof is waterproof.
Step #5 - Seal It All Up
Finally, you'll need to apply sealants to make sure that your RV is watertight. You can use caulk, lap sealants, or RV sealant tapes to cover any seams, gaps, or cracks that might be present.
Just make sure to inspect your work carefully and fill in any areas that might lead to leaks again in the future.
When that's all done, consider applying a high-quality RV roof coating to the entire roof to keep your repair job in tip-top shape for as long as possible.
Can You Fix Water Damage from Inside the RV?
If the damaged area is relatively small and isolated, you may be able to access damp materials from inside. You'll still need to give them adequate time to thoroughly dry out before replacing your wall or ceiling panels. But it may be possible.
On the other hand, you'll still need to find and stop your leak or else things are only going to get damp again and your problem is only going to get worse over time. Small leaks, cracks, or gaps can be filled with lap sealants or RV sealant tape.
But if you're dealing with severe water damage, rotten wood, or soft spots, you're likely looking at more serious water damage that may require you to tear open the roof of your RV.
In other words, soft spots and water damage are usually jobs that are not to be taken lightly.
When to Call a Pro or Replace the Roof Entirely
We're not doubting your proficiency as a strong, savvy, do-it-yourself kind of RVer. However, if you notice any of the following signs...
- Widespread softness or spongy areas on your roof
- Signs or total structural failure, like bowed out walls or sagging ceiling panels.
- Visible mold or mildew in multiple locations
...it may be time to call in the big guns. Reach out to a professional for help or consider a full roof replacement.
You can also check out our RV roof repair manual to find out whether you can tackle the job yourself or if it's time to consider a full replacement.
Frequently Asked Questions - RV Roof Water Damage Repair
If you've noticed soft, spongy spots on your roof, it's never a good sign. Take a look at these frequently asked questions to help you get a better idea of whether or not you can attempt to repair that soft spot on your own.
How long can I wait to repair a soft spot in my RV roof?
You can wait as long as you want. But if you've got a soft spot, the damage is only going to get worse if you don't act now. Think about it like this: Every time it rains, that damage is getting worse. Water will keep getting in and the dampness is only going to spread. So the longer you wait, the more expensive and intensive your repair job is going to be.
Is it safe to walk on a soft RV roof?
No. If you've got structural weakness or rot, it's best to avoid walking on your RV roof. You risk putting your foot through or actually falling through the ceiling, which is going to hurt and will only make the damage worse than it already is. If you must access the roof, do so from a ladder, or place a long 2x10 or solid pieces of wood perpendicularly across the roof to help support your weight.
How much does it cost to repair water damage in an RV roof?
It really depends on the severity of the damage. Repairing small leaks and performing minor soft spot repairs might cost anywhere between $100 to $500. But if you need to contact a professional for help or if you need a full roof replacement, the project can cost anywhere from $1,000 to $5000 or more.
Can water damage spread to the walls or floor?
Yes! For starters, water will always flow downward. So if you've got a leak on your roof, the water that finds its way inside will gradually make its way down your walls and into your flooring panels. Mold will also spread and make its way from your ceiling, into your walls and into the rest of your RV if you don't take action to stop your leaks and fix the damage now.
Should I coat the roof after I repair it?
Yes. Once you've repaired your roof, we recommend coating your RV roof once a year to ensure that it stays sealed tight and water stays out. We also encourage you to inspect your RV roof at least once or twice per season to try and catch those pesky roof leaks before they lead to more serious damage. In the very least, inspect your RV every spring, before taking your rig out on the road.