DIY: RV Window Replacement
We caught up with Andrew Phillips and the team from The RV Repair Centre to give us the run down on resealing a window.
Windows are a great part of caravanning, they let light and fresh air in. They can also let water leaks in if not properly maintained. If you monitor your window seals and replace them as required, you can prevent major water damage from occurring.
Basically, the process involves completely removing the window from the wall opening, removing the old sealing material, replacing with new sealing material and reinstalling the window. Therefore, you could also use this guide if you needed to replace an entire window assembly.
There are some variations in how you go about it depending on the type of wall on your van. In this instance, we are looking at a profiled wall where foam strips are the recommended method. With smooth sided walls depending on the surface material, silicone sealant may be preferred.
This is a relatively simple process but you still need to get it right! If you get it a bit wrong you could end up with a water leak, if you get it really wrong you could end up with a window falling off hurtling down the freeway.
You will be working with flammable solvents so common sense is required. Using the wrong solvents can cause damage to paint and plastics. Using the right silicone is imperative. A neutral cure silicone will create a seal that can be mechanically broken if required. Other silicones will create a permanent adhesion that you will never get off. Foam sealant strips come in various widths and thicknesses — your RV repair centre can help you select the correct one for your job.
1. Remove screws and protect well paint
Remove the screws holding the window frame to the wall. They may have been in there a long time so be very careful not to strip the screw heads. Make sure the screwdriver head fits perfectly — not too big or too small. It might be better to start with an old fashioned manual screwdriver rather than a power driver so you don’t overdo it. As you remove the last of the screws be wary that the window may fall off the wall.
It is far more likely that you will need to prise the window off. To protect the wall paint, apply masking tape around the edge of the window frame.
2. Remove window
Test to see if the window can be gently levered off with a screwdriver. Do not apply too much force as you may damage the wall or the window frame. (Much older installations used putty to seal the windows and tend to come off more easily.)
More recent installations used silicone to make a seal which will need to be broken all the way around with a scraper. Applying mineral turpentine to the silicone with a rag will help soften it up if you are having trouble breaking the seal.
With the screws removed and the seal broken, the window should now come out easily.
3. Remove sealant and masking tape
Use a plastic scraper to remove the sealant that was behind the window frame. The guys at The RV Repair Centre use cut up pieces of old polycarbonate caravan windows as it is a lot tougher than plastic scrapers from the hardware store. Again, mineral turpentine may help to soften the sealant up.
Use the plastic scraper to remove the sealant off the wall, being careful not to damage the paint. Again, mineral turpentine can be useful to soften the sealant.
4. Clean wall and inspect window mould/structure
Check the window plastic moulding is still intact. Handle it carefully as old plastic ones could be quite brittle. If the plastic moulding needs replacing or you find water damage to the caravan structure or internals consult your RV repair centre.
5. Scrape sealant and clean window frame
In this instance we have the old style putty being removed with a chisel being careful not to damage the inside of the window frame.
Use the plastic scraper to remove the remaining sealant including in any grooves.
Then, clean the window with mineral turpentine — it is important to have the surface as clean as possible for the new sealant to adhere properly.
6. Remove turpentine with methylated spirits
Mineral turpentine leaves an oily residue which needs to be removed. Make sure you use a fresh rag to apply the methylated spirits otherwise you will be just smearing more mineral turpentine.
7. Apply foam seal to top edge of window frame
Apply the foam seal across the full width of the top section of the window frame, then remove self-adhesive backing.
Apply foam seal around the other three sides as a continuous piece, as this eliminates joins. The foam seal can be worked around corners, provided you remove the backing tape as you approach the corners first.
8. Trim foam seal
Ensure there is no gap with the foam seal. Make sure all of the mineral turpentine residue has been removed from the walls with methylated spirits.
9. Apply a narrow bead of silicone on the wall
Apply silicone to the wall only, as putting it on the window will make it messy to handle. Use a general purpose neutral cure silicone. Only a fine bead is required as the silicone is just helping the foam seal to tack to the wall. Excess silicone will only ooze out and make a mess that you will have to clean up.
The wall cladding has a number of horizontal joins in it. Applying silicone on the edges of the cladding where the joins are will protect against water seeping in.
10. Carefully place window in opening
Before placing the window in the opening have your screws and screwdriver handy so that you can keep one hand on the window while you get the first screw in. Place the window in such that you don’t smear the silicone all over the place.
11. Screw window frame to wall
Use new screws as your old ones may have damaged heads. Make sure you use stainless steel, other materials may corrode. It is important not to over torque the screws otherwise you can damage the window frame, damage the wall or over compress the seal to the point it becomes ineffective. The RV Repair Centre use a lower torque driver for putting the screws in than the one they use for taking the screws out. Put the first screw in a top corner until the foam just starts to compress. Then place a screw in the other three corners driving to about the same depth. Drive the remaining screws in gently. Go around and torque all the screws a bit further, watching the edge of the window frame to ensure you don’t overtighten to the point of bending the window frame.
Wipe away any excess silicone that has seeped out.
12. Apply a fine bead of silicone along the top of the window frame
The top is where water can pool so a little extra layer of protection will help.
Smooth of the bead.
13. Carefully trim off any bulging foam seal
Be careful not to damage the paint. A very sharp knife will make it easier. Inspect the frame from the inside for any excess silicone, and you’re done.
IF IN DOUBT, CONSULT A PROFESSIONAL
Improper maintenance can lead to injury, death or property damage. Maintenance work of this nature should only be undertaken by people with suitable competence. Information provided is general in nature, not comprehensive and should only be taken as a guide. Individual discretion must be exercised and persons undertaking described tasks do so completely at their own risk. Publishers and creators of this content accept no responsibility for loss or damage.
Thanks to Andrew Phillips and the team from the RV Repair Centre for their assistance.