Skip to content

How to install RV Slide-Out Seals

If your slide-out seals are cracking and deteriorating, it’s time to change the seals. When slide-out seals crack, they end up creating gaps and fold away from the slide-out. This lets water and pests get into your RV.
Let’s talk about changing the seals. We are going to need a few things to get started.
Tools we need:
Steele’s 4 Steps to New Seals:
  •  Identifying Seals 
  • Removing Old Seals
  • Cleaning & Prepping 
  • Installing & Trimming

Identifying Your Seals

RV Manufacturers use a wide variety of seals for their slide-outs. One of the most common seals you will see will be a bulb seal that slides onto the track of a wiper seal. The wiper seal sweeps against the side of the slide-out to remove dust and debris. To ensure a tight seal, you will want to make sure the blade length of the wiper seal is long enough to 1. Be mounted on your RV and 2. Scrape the side of the slide-out. Making sure of these two things will ensure that you have a tight seal.
You will want to take note of the dimensions of your seal. Doing so makes finding a new seal easy. You can also go online and download our RV catalog. You can also request a mail catalog if you prefer to have one on hand (p.s. it’s free). If you have the dimensions, then you can find the profile of the seal you need, and cross reference the dimensions to make sure you are getting the appropriate length seal.

Removing the old Seals

This is where masking tape will come in handy. Laying down a layer of masking tape around the entire perimeter of the slide-out (next to your old seal) will ensure that you keep your new seal straight. The tape will also act as a barrier to protect your RV from scratches and excess glue. Once you have laid down the layer of tape, then you can remove your old seal.
We offer a large variety of seals. Some are adhesive backed and some are glue on. You can take note of how your original seal was installed, but know that your new seal does not have to be installed the same way.

Cleaning and Prepping the Surface

First, you will need to sweep off the top of your slide-out. There is always extra leaves, sticks and debris hanging out up there. Next, wipe of the dirt and debris that the old seal has trapped over the years. You can do this with a shop rag or old t-shirt. After cleaning off the dirt and debris, you will want to spray the old adhesive or glue with an adhesive remover. This breaks down the glue and makes it easier for you to come back and scrape off. Use your scraper tool to remove the residue of the old seal. Doing this will give your new seal a clean and smooth surface to cling to.
Finally, wipe the perimeter with an alcohol pad. This will remove and oils or residue that might be left behind. Again, this makes sure your new seal has a clean surface to adhere to. You can also take an alcohol pad and use it to wipe down the new seal where you will be gluing. This removes any residue that might still be on the seal from the manufacturer.

Installing and Trimming the new Seal

For installing seals – a little bit of glue goes a long way. They key to installing any glue-on weatherstripping is to use a very thin line of glue, and spread it out with a popsicle stick. Spreading the glue allows the entire surface area to be covered without creating a mess.  After you have added your glue to the surface of the RV, you will want to do the same for the new seal. Let the glue sit for a few seconds and become tacky. Letting the glue become tacky lets the seal adhere fairly quickly.
Once you feel the glue become tacky, add a very thin line of glue to one of the surfaces. Now you can start installing the seal. We recommend starting at the bottom of the slide-out. Once you start to install the seal, make sure that you leave a little extra at the end that you can cut off later. It’s best to install the seal in 2-3 foot sections to keep your seal straight and make sure you are getting good adhesion.
After you finish installing the seal on the bottom of the slide-out, you can cut off the excess, but remember to leave just a little extra for a final trimming. For the top of the slide-out you will want to glue the center first (letting extra hang off the sides) so you can easily adhere the corners and sides. You can even use your old seal to create a template for the corners. Once you reach the bottom of the sides, you can start the final trimming.
You will want the side to overlap the bottom, so you will need to trim the seal to be just inside the bulb from the side seal. Trim the side seal flush to the masking tape line. Then, trim a bulb width out of the side seal lip to allow space for the bottom bulb to bump up next to the side bulb. Doing this diverts rain from the RV and allows the hollow section of the bottom bulb to be sheltered.
Now you can remove your masking tape! If there is any mess left by the glue, you can clean it up.

For all your RV weatherstripping needs, Steele Rubber Products provides high quality products made from EPDM rubber.  You can find a complete list of all of our doors & compartmentswindow sealsslide out sealsinsert trim & screw track covers and  universal parts on our website  Additionally, you can download a free  RV Parts catalog online or give us a call to request a mail catalog 800-230-6752.
Don’t forget you can follow us on all your favorite social media platforms including