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How To Install New Window Trims

How To Install New Window Trims

At some point, you may need a new PVC trim. Maybe wood rot or mold has created a hole in the trim, and you’ve got a draft coming through. Or perhaps you accidentally hit a child with your car and need to get that windshield replaced. Whatever the case, it’s time to learn how to install new window trims.
If you plan on doing this yourself, here’s some advice:

Pick up the right-sized replacement

It is best to buy PVC trims that are at least the same size as your existing trims. You don’t want to replace a 4” trim with a 3” trim. You can always remove or add material. If something is too big, you can always wrap it in wood filler, which is less permanent than plaster filler but still works great on trim.

Gather tools and supplies

The tools and supplies you need depend on the type of window trim you buy and the kind of damage to the window trim you have now. If you have wood rot or mold, use sill sealant instead of plastic foam (as this will help prevent mold). If mold or rot is not an issue, use the plastic foam.

Remove damaged trim

If the window trim is old or damaged, you will need to remove it first. If there are no wood rot or mold issues, you can usually use a simple chisel to start breaking up the trim. If there’s wood rot or mold, you may use a chisel, a hammer, plenty of wood filler, and plaster filler (depending on how deep the damage goes). After that, cut out the rotten wood and remove it with a crowbar or pry bar (or whatever tool works best). It is a good idea to have eye protection and a dust mask when dealing with mold or rot issues.

Apply sill sealant

If there was no wood rot or mold, you can now install the plastic foam and window trim simultaneously. It is as simple as trimming the plastic foam to fit your window opening, then using wood glue to attach it to your PVC trims. Once this dries, paint it the color of your choice. If you have wood rot or mold, apply wooden sill sealant where the subfloor meets the outer siding of your house. Allow this to dry and cure according to the instructions on the sill sealant package.

Install window trim

Trim is tricky, as there are different trimming options, but most follow a few basic steps: install and apply a sealant (if you have wood rot). Make sure all trim parts fit together well before you glue them together. While you can use wood glue (not glue gun glue) to hold them together, it’s best to get clamps for larger sections of trim (wooden trims and molding). Once they’re together, use screws to attach them to the siding and the window glass.

Once you figure out how to install new window trims, you are ready to go. You don’t need a lot of tools to get the job done, but you should have your tools ready in case you need them. Install the best quality window trim, which means you won’t need to replace it for a long time. Choose Sherwood’s EX-Cel PVC trim and enjoy over 30 years of outstanding performance.