Spotting RV sidewall delamination
Spotting RV sidewall delamination
Monday, August 20, 2012
Starting in the 1990’s most RV manufacturers changed their construction techniques for RV sidewalls. Prior to this time, with the exception of more expensive versions, sidewall covering consisted of ridged aluminum siding. Today, the sidewalls on most RVs are smooth, like the photo above. While this makes it easier to keep a rig clean and many prefer the look, it is not without its potential for problems. An RV sidewall typically consists of a ‘sandwich’ of the following, thin wood paneling (known as luan) glued to a 1-2 inch styrofoam core. Inside, you will see either wood paneling or (more often) wallpaper covering the luan. Outside is a thin layer of fiberglass material, often referred to as ‘gelcoat’. Many RVs spend their time 7x24 parked outdoors next to a home or a storage lot. Much like your home, they take a great deal of abuse in the weather. As an RV ages, owners often do not properly maintain seams of the RV near the roof where the sidewalls meet, windows are installed, vent openings, and so forth. The expansion/contraction and UV aging that happens each day as outdoor temps change breaks down these sealants. In addition, RVs (unlike automobiles) are often built using inexpensive hourly labor and suffer high employee turnover rates. It is readily possible to buy a brand new RV that did not have its seams properly sealed. Either way, water can find its way into the walls.
Once water has entered the wall, it starts its work at breaking down the luan mentioned above. In most cases, with the exception of a glue failure, the fiberglass has not separated from the wood. Rather, the wood itself is decaying and separating from the styrofoam core through a steaming effect. The result can often be spotted by running your hand along the surface of the RV near vents, below windows, near seams by the top of the roof, etc. The source of the leak may not necessarily be right above the impacted area as water can travel along frame rails and so forth.
When considering the purchase of a used RV, spotting such damage is important. While some delamination can be minor and is more of an aesthetic issue if the source of the leak has been addressed and framing members of the RV have not been compromised, any delamination greatly reduces the selling price/value of the RV. There are shops that can perform a repair, but unlike the days of old where a leak is repaired and aluminum siding is replaced, such repairs often require an entire sidewall to be removed and other techniques to address the problem. In short - it is very expensive to repair. Thus, I recommend that if you are close to buying an RV, consider calling a mobile RV tech and paying a few $$ for them to inspect it before purchase. Don’t assume that a dealer will be honest about it either. I found during our RV purchase process that they often downplay the damage and act ‘surprised‘ when you find it.
If you’ve already purchased an RV and later discover delamination, don’t panic. The first and most important thing to do is to find the source of the leak and get it repaired immediately. Allowing the affected area to dry out is also important. Also, unless it is an emergency, don’t just use silicone caulk to fix it as it is not sufficient for more than an emergency/temporary repair in most cases.
As part of our purchase, I had an RV tech completely remove the all of the sealant on our rubber roof, including some cheesy work that the prior owner had done, and install new Dicor self-leveling lap sealant. This also corrected a leak that I uncovered near the bathroom skylight (skylight was removed and re-set) and corner bathroom wall. While we saw no evidence of delamination, in both cases, we used this as a negotiation to both significantly reduce the selling price of the RV as well as to address the leak problem. Now that we have had the rig for awhile, I do indeed see a small area on the sidewall where it joins the roof that has a slight bulging that would be the first potential sign of delamination. The area is still ‘rock hard‘ when I press on it, however. This issue likely was there from the first day that I purchased the RV, but somehow missed as part of my initial thorough inspection. While disappointing, I’m confident that there are no more leaks that could result in further damage and will keep an eye on the area to note any potential changes. In our case there are no structural issues and it is limited to being aesthetic at this point. Regardless, I am glad that I had negotiated a much better price at the time of purchase as it may impact the rig’s value when I go to sell it.
I have a hypothesis that as not yet is proven. RVs that spend 100% of their time outdoors, regardless of sealing all joints, may well still show delamination as they age. Differing temperatures between interior/exterior can contribute to condensation and days where the rigs walls reach well over 100 degrees and cool to 40 degrees overnight certainly can have some impact on the glues used in the sidewall ‘sandwich’. We notice in our rig if we camp in cool weather that condensation can form on interior walls even when we keep vents open for adequate ventilation. RV manufacturers have learned a lot about improving the sandwich over the years as many rigs were repaired under warranty (Winnebago, among others) to address premature failures not related to leaks. Unfortunately, most RV manufacturer warranties for this type of issue are very short (12 months). Also, with the economic collapse of 2008, many RV companies are no longer in business or have been ‘brought back from the ashes‘ through a bankruptcy. My rig (made by Fleetwood) is an example of a company that still exists today after bankruptcy and purchase by an investment firm. Today, Fleetwood only manufactures motorhomes, leaving thousands of customers with trailers and popup tent trailers without a ‘mother ship‘ for support. The good news is that most RV systems are made by 3rd parties anyway (fridge, suspension, furnace, hot water heater, etc.)
To feel best about all of this, as an added precaution to preserve the longevity of our RV, I have it parked in a metal pole building on a cement slab. This assures that our rig is in a 100% shaded spot and out of the pacific northwest weather. I consider the cost of this storage good insurance to protect our rig, improve resale value, and reduce how often I may need to have roof, windows, and other areas resealed. It certainly has been in the rain and sun since then, but only when we are on one of our many outings. If you are considering an RV cover such as those made out of Tyvek, please be aware that they are problematic in the Pacific Northwest. I had one on a popup trailer that did a good job of cutting down on the UV, but water still easily gets through it, resulting in a ugly green mess on the roof of the rig and mildew on the insides.
Happy travels.
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