Window cladding, also known as window capping, is PVC that’s put over the window surround to protect it from the elements. If it cracks, it can be repaired.
Step 1 - Locate Cracking
Locate where the cracking is on the window cladding. Any crack will let in water, which can damage the window frames. Begin by cleaning off the area carefully with soap and water. This will allow you to make the repair invisible. If not you’ll need to make the repair on the outside of the cladding.
Step 2 - Repair
Mix up some PVC sealant to the proper consistency and work it into the crack very carefully, being certain to fill it. Allow the sealant to cover a little more than the crack and wipe up any excess with a rag.
Step 3 - Finish
Allow the repair on the window cladding to dry. Examine it. If it’s very obvious, you might want to consider painting the area so it blends in easily. Touch up paint will do the job and mostly hide the repair. Do the job carefully and match the paint well.