VIDEO: How to check for damp in your caravan

Published in Caravan Guard News, Caravanning Top Tips, Videos on   - 22 Comments

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  1. Day says:

    Comments are good. Have swift challenger 480 2016 se. damp reading not that high thanks to your meter readings put mind at rest, been sold a damp van. However on checking van see little holes it seems pervious owner as had issues not mentioned. I will use advice leave heat on low, have covered van roof, have it resealed trust it prevents water ingress that’s what damp is? So keep an eye on your vans etc. let you know how it works out when I have funds to have it re chalked, take advice mentioned on this forum site thank you. ya all have good day now happy caravanning.

  2. Roger Boud says:

    Very useful video but bit late for me! Just picked up my Swift Conqueror having had some very expensive damp repairs done around the toilet area. I was advised by the gentleman who did the repairs and has many years of experience, that I should never fill the Thetford Cassette flush tank with too much water, even when on site. I never travel with very much in this tank. It seems that there is an ‘O’ ring joint which often lets water through. He has come across this problem time and time again. The problem, of course, is you can never be certain just how much flush water is in this tank – you know if it is empty or if it is full! A built in gauge would have been useful. Any DIY measuring ideas would be useful. Thank you

  3. Bryn Bell says:

    In 2004 I bought a two year old Lunar Lexon Twin axle. It came with a one year warranty from the caravan sales. No sooner the warranty run out I detected damp lots of it.I took it for repair to a caravan repair specialist cost me £1800. they had the van forever and still didn’t get it right it took several visits for that.I have found damp twice since then and repaired it myself.When I removed the awning rail an absolute nightmare to separate it from the sealant, I found that there was an area where there was no sealant causing the leak.Working in a local authority I asked the supplier of the sealant used about it’s effective life and he told me it should never fail as this same sealant is used to hold together speedboats and luxury yachts.
    So damp check regularly particularly any area where something is fixed to the body, Awning Rail.Sealing strips,Doors and windows Etc.

  4. John Case says:

    Colin says, “So as the saying goes you get what you pay for”, which is often true – but don’t discount the Adria range which is well known for build quality, even at a relatively ‘cheap by comparison’ price! Mine is excellent too.

  5. David Lomas says:

    Some excellent tips and information, but in this day and age, we should never have to suffer a damp problem if the caravans were designed and built properly in the first place. When was the last time a new car had a “damp” problem? The manufacturers fill the vans with all the latest bling, but seem to cut corners on simple design. We seem to accept that all our vans will leak at sometime in their life, some sooner than others, but it should NEVER happen in the first place.

  6. Chris Scrimshaw says:

    There generally are too many vent holes for gas drop etc to make it worthwhile using the moisture absorbing crystals, its like trying to de-humidify the Northern Hemisphere.

    Allowing air to circulate is the best option if you cannot use an electric heater to keep the internal temperature slightly elevated, its the change in temperature along with the dew point of moist air which causes condensation issues.

    Moisture ingress most often due to shoddy assembly practises is the real issue, getting the manufacturers to address that aspect is what the Clubs and magazines should be doing…..

  7. colin turner says:

    some good advice, points, etc, but also some simple ones missed,touching the rubbers on windows or doors will give a false reading, checking the internal seam joints is a good place to look and maybe remembering to keep your floor air flows clear.

  8. Steve Exall says:

    I leave my caravan connected to mains power supply over winter to keep the battery on full charge, I also set the thermostat to switch the electric heater on when temperature within caravan drops to about 5deg I move all upholstery away from the interior walls for better air circulation will these precaution help prevent condensation or will it contribute to it, the caravan is also covered with a pro-cover.

  9. Sid Withey says:

    I would emphasise that a damp meter is essential. By the time you smell, feel or see damp it is likely that severe damage has already occurred. For about £15 it could be the best investment you will ever make.
    It’s also important to check around water pipework.
    Damp measurements will often be higher around floor level than higher up simply because colder moist air will tend to sink.
    As mentioned in a reply above less than 15% should be ok

  10. Colin says:

    The above advice for damp is good, however something that has not been mentioned, is what caravan are you dealing with, the better the build quality the more likely you are not to suffer damp. I have an–hymer Nova caravan 2002 build that have six-year warranty when new, I have had this caravan approximately eight years and still no damp. So as the saying goes you get what you pay for.

  11. John Wright says:

    I found it very helpful and the responses. I cover my caravan over the winter with a breathable cover and also use a dehumidifier every month overnight and this has helped to keep the caravan dry and condensation levels low.

  12. Richard randall says:

    I use a non-invasive inductive moisture meter. It is very easy to use and does not have probes therefore no holes in fabric of caravan wall. It measures the average damp down to 20mm. I always run the meter over the internal surface before it is serviced and tell the engineer to check any areas that have higher readings. Only problem is if wiring or metal is within the caravan wall as the meter, being inductive, will give a 100% reading. My meter cost £28. Well worth the money for the easy of use.
    I also use a small electric dehumidifier which draws 1 litre of water a week from the ambient air, and keeps the inside of the caravan bone dry including fabrics.
    Dehumidified water is used on orchids and in steam iron!!

  13. J ewan says:

    Very interesting and valuable information given on how to check for dampness in caravans. However, on newer caravans the wall / ceiling boarding can be of honeycomb construction and should not be pierced by using the prongs of a moisture meter. Therefore it is advisable to seek dealers advice on how to carry out dampness checks.

  14. Douglas King says:

    Is there a problem using a dehumidifier in the caravan during winter months ie is it cloaking any dampness problems.

  15. David Coffield says:


  16. John Leonard says:

    You do not give meter readings to show what is a good reading and what is a bad reading.
    Would be useful.
    John leonard.

    • Liz @ Caravan Guard says:

      Hopefully the chart will have helped John. If you’re getting a reading of between 15 and 20% then you might want to investigate further and check again in a few months. A reading of between 20 and 24% warrants further investigation, particularly around that area. Between 30 and 35 % there’s probably water ingress and you’re going to need to get it checked out.

  17. Tam dawson says:

    Very used full good comements

  18. Pete Dutton says:

    Very good tips. Thank you.

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