Water finds its way into off-road campers at four places far more often than anywhere else. Owners have reported leaking skylights shortly after delivery, water around windows, water where annex poles enter the roof, and the one that catches everyone out: water in the cupboard above the wheel well.
Each has a different cause and a different fix, and the first job is working out which one you actually have. Water travels. Where it appears is often not where it got in.
First, find where it is really coming from
Water runs downhill and along any surface it can cling to. A drip at a window sill may have entered at the skylight and tracked along a ceiling panel.
Dry everything, then test one thing at a time. Hose one area, wait, look. Then the next. Testing the whole roof at once tells you the camper leaks, which you knew.
Start at the top. Test the skylight and roof fittings first, then windows, then lower down. Water from a high entry point can appear at every lower one.
Look for the stain, not the drip. A tide mark on a panel or a discoloured patch of ceiling lining shows the path the water took while you were not watching.
Check from outside in the rain, or with a hose, at dusk with a torch inside. Light leaking out is a gap, and it is the fastest way to find one.
Skylights and roof hatches
The most frequently reported leak point, and the one owners most often mention as appearing early in ownership. Some were fixed under warranty, which tells you it is a known fault rather than something you did.
Why it leaks: the skylight frame is bedded onto the roof with sealant, and the roof flexes on corrugations while the frame does not. Sealant that was thin, uncured or badly applied cracks at the edge, and once there is a crack, capillary action does the rest.
How to check: get on the roof and look at the sealant bead around the frame. Cracks, gaps, lifted edges or sealant that has gone chalky mean it is time. Press the frame gently; movement means the fixings are loose or the sealant has let go.
The fix: remove the old sealant completely, clean back to bare surfaces, and re-bed the frame with a sealant rated for roof use and UV exposure. Do not lay new sealant over old. It looks tidy for a month and then fails along the same line.
Inside, a skylight insulator does nothing for a leak, but it does stop the condensation that owners often mistake for one. A cold skylight in a warm camper drips. If the water only appears on cold nights with no rain, that is condensation, not ingress.
Windows
Two different failures here and they are easy to confuse.
The seal. Water at the bottom corner of a window, especially after driving in rain, usually means the frame seal has hardened or lifted. The bubble-profile EPDM rubber seal is the universal fix for a window frame that has lost its compression.
The window not closing fully. On a dual-pane window held open by gas struts, a tired strut lets the window sag so the latch does not pull it fully home against the seal. It looks closed. It is not. Water gets in at the top edge and runs down inside the frame.
The tell is a window that needs a push to latch, or that drifts open a fraction when you let it go. Replacement window struts are sold in pairs and in several lengths, so measure your existing strut end to end before ordering. Available in 8 inch, 8-1/4 inch, 10-3/4 inch and 11 inch.
A window latch that no longer holds positively has the same effect and is the other thing to check when a window leaks at the top.
Annex pole entries
Where annex or awning poles pass into the roof or body there is a hole, and it is sealed only by whatever grommet or boot was fitted around it. These get disturbed every time the annex goes up and down, and they sit exactly where rain runs off the roof.
How to check: with the annex down, look at each entry point. The boot should be seated and undamaged, and there should be no gap between it and the body.
The fix: reseat or replace the boot, and seal around it. If the pole itself is bent or the end fitting is damaged so it no longer sits square, the boot will never seal around it. A complete Dominator pole set is the answer when the poles have had a hard life; a single bent pole is worth straightening or replacing before it damages the entry every time it is used.
The wheel well cupboard
The one owners describe as everything in the cupboard getting wet, and the one most often misdiagnosed as a window leak.
What is happening: the wheel arch is a formed panel inside the body. Water thrown up by the tyre hits it at pressure and at speed, and any seam, fixing hole or gap in the arch lets it through into the cupboard above. Wet roads do this. A water crossing does it far more.
How to check: empty the cupboard, dry it, and look at the floor and back wall for tide marks. Get underneath and look at the wheel arch from below for seams and fixings. Then hose the tyre from behind, hard, the way the road does, and look inside.
The fix: seal the seams and fixings of the arch from underneath with a flexible sealant that stays flexible. The arch flexes and a rigid sealant cracks. Anything that goes through the arch needs a grommet, not a bare hole. Consider a mud flap if the tyre is throwing water forward into the arch at a bad angle.
What to seal with
Match the sealant to the job. Roof fittings and skylights need a UV-stable sealant rated for roof use. Wheel arches and underbody seams need something that stays flexible. Window and compartment gaps mostly need a compressible seal rather than sealant at all.
Two rules that apply to all of them:
- Clean back to bare, dry surface first. Sealant on old sealant, dust or damp fails.
- Remove, do not overcoat. A new bead over a failed bead fails along the same line.
What is not a leak
- Condensation. Cold nights, warm interior, no rain: that is breath, cooking and showers condensing on the coldest surface. Ventilate and insulate the skylight.
- A wet bathroom floor after a shower is usually the shower door seal or the tray, not the body.
- A damp mattress against an outside wall is nearly always condensation, not ingress.
After the repair
Test it. Hose the area you sealed, wait, check inside. Then test again after the first trip, because the road tests it differently from a hose.
If you have found the water and cannot work out where it entered, send us photos of the stain and the outside of the camper around it and we will help narrow it down. Everything ships from Upland, California.