What are the causes of a leaking trailer roof?

In this blog post, we answer the question “What are the causes of a leaking trailer roof?” We will discuss the common reasons for trailer roof leaks and talk about maintaining a trailer roof. We will also describe the importance of resealing the sides of a trailer roof and list out a few maintenance and repair tips to help your trailer roof last longer.

What are the causes of a leaking trailer roof?

The causes of a leaking trailer roof are:

  • Cracked roofing 
  • Physical damage
  • Damaged roof racks 
  • Aging reasons 
  • Ladder mounts

Trailer roof leaks are caused by many reasons and it is important to identify the main causes. Preparation is key when it comes to a leaking trailer roof. By preparing in advance, you can also prevent the trailer roof from leaking. There are a few common reasons for trailer roof leaks. Here are some of them listed below.

Cracked roofing 

  • A cracked roof is not something new as many trailer roofs experience this from time to time. This is more common in trailers that have fiberglass roofs. 
  • A motorhome roof can get cracked due to heat and wear and tear. Roof cracks can also be found near attic vents, pipe vents, wire ports, roof fans, skylights, etc.
  • Finding cracks near these components is common. These are self-leveling components and they are prone to become brittle and crack over time. 
  • It is important to protect these components by checking often for any cracks. Since vents and skylights have gaps, there are chances of water coming through. Hence, cracked roofing is a common cause.

Roof racks and Physical damage

  • Not every motorhome has roof racks, but the ones that do are attached directly to the roof and these roof racks can cause damage. 
  • Leakage can happen over time if these roof racks are attached to your trailer roof. 
  • Trailer roof leaks from roof racks usually come from the screws that hold the rack to the roof. This can happen over time and it can be years before roof racks start to leak.
  • Physical damage is probably the first thing that can happen to your trailer roof. 
  • Falling tree branches are one major cause of causing cracks thus leading to a leaking trailer roof. 
  • The trailer roof can come in contact with many things including snow, rain, extreme heat, and rough climate conditions. Physical damage is bound to happen to your trailer roof.

Aging of the roof 

  • The aging of the trailer roof is something that you cannot prevent and it is one of the most  common reasons for a leaking trailer roof. 
  • The roof of a trailer will tend to weaken due to exposure and it will eventually lead to cracks and leakage. 
  • Remember that your trailer is always exposed to sunlight or extreme cold temperature. 
  • There is an age limit for your trailer roof and it cannot last beyond a particular time.

Ladder mounts 

  • The ladder is always attached to the roof of the trailer and this can also be a reason for a leaking trailer roof. 
  • The ladder mount points can be the source of a leaking trailer roof. 
  • Some trailers have leaks at the rear since the ladder is located through the side of the frame. 

Trailer leaks can be because of excessive wear and tear or bad climatic conditions. Leaking trailer roofs are a common thing and all motorhome owners will encounter this problem some way or the other. Unlike a car roof, trailer roofs are more vulnerable since they come across unexpected damage due to harsh conditions.

Regular maintenance is the only way to prevent an RV roof from leaking. Inspecting the RV roof and checking for any damage regularly is recommended. The trailer roof is also prone to mildew and deterioration. Water is the main source for destroying a trailer roof and your motorhome is always prone to rain.

Maintaining a trailer roof 

Maintaining the roof of the trailer is the only way you can prevent any leaks. Clean the exterior of the trailer roof once in two weeks. You can also do a paint job every year to protect the roof and keep it neat always. Be sure to check for any dents and remove any debris or other materials if you find any stuck to your roof.

Determine the type of the roof

The type of trailer roof is also important. A fiberglass roof will require more maintenance than an aluminum roof. Some trailer roofs are made of thermoplastic polyolefin and synthetic rubber. These roofs will also require more maintenance. Be sure to keep an eye out for the seams. Try covering the roof of the trailer when not in use.

Maintain the seams 

  • It is important to maintain the seams since they are at the rear and the front terminators of the roof. 
  • Examine and clean the seams carefully every once in a while. It is recommended to clean the seams at least four times a year. 
  • Never neglect the roof if you find any dampness or any chance of water dripping through. Immediately take your trailer to a repair shop or fix the issue on your own.
  • Be sure to get a proper sealant from a store that is specialized in these products.
  • Silicone-type sealants are fine on the sides, but they are not compatible with the trailer’s roofing materials since they can separate from the roof. There are trailer roofing solutions and liquids that are used for this purpose.

Reseal the sides of a trailer 

Many people think that the roof of the trailer is the main part that needs to be fixed. The sides of the trailer are equally important when it comes to resealing. You can also use foam gasket tape for the sides, doors, and windows. Silicone caulk can be used to back up the foam tape around the doors and windows to keep in sealed. Thus, preventing water from entering.

Trailer roof repair tips 

Here are a few extra tips to maintain a trailer roof 

  • Regular maintenance is the key no matter the type of roof that you have. Be sure to have some of the basic materials handy for maintaining your trailer roof. 
  • Some important things are roof patches, roof cleaners, a caulking gun, a seam roller, sealant, and primer. These things will also help you while traveling in case you need to make a quick repair.
  • Rubber roofs need to be cleaned often. Avoid using cleaners that have petroleum solvents. 
  • When scrubbing the roof, use a medium bristle brush. 
  • You must remove mildew as much as possible since it can cause damage to your trailer.
  • While cleaning, be sure to have a thorough inspection of all the sealants and seams.

Importance of sealant for a trailer roor 

Just like any other part of a trailer, the roof is one of the most important parts that need to be taken care of. Constant maintenance will prevent the roof from getting damaged. Just be sure to get those leaks fixed as soon as you find one. A leaking trailer roof is not a good sign and it can only become worse as time passes by.

  • It is always recommended to apply some fresh sealant even if there are no issues with the trailer roof. Experts have recommended to recoat and reseal the roof of a trailer at least once a year. 
  • Make sure to purchase products that are designed for trailers and the type of roof that you have. You can get these products from specialized RV or motorhome stores.
  • Apart from all these, it’s good to keep the trailer out of the sun, especially when it is extremely hot. Extreme cold is also a big disadvantage for a trailer. 
  • Be sure to have a roof cover that can keep protecting your trailer even when you are out camping. These covers are not too expensive and are more like a one-time investment. A cover can also protect your rig from rain.

Water and extreme heat are the enemies of trailer roofs. Falling branches and other accidents are common, but make sure that water does not collect on the roof of the trailer for a long time. Water can soak into the roof and cause trouble later on. By following a few simple steps, you can easily maintain the roof of a trailer and make it last longer.


In this blog post, we have answered the question “What are the causes of a leaking trailer roof?” We have discussed the common reasons for trailer roof leaks and talked about maintaining a trailer roof. We have also described the importance of resealing the sides of a trailer roof. Drop us a comment below and let us know if there are any other tips to maintain a trailer roof.



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