Though vinyl siding and trim are engineered to last many years, it’s important to maintain them annually with a thorough, professional cleaning to remove dirt, grime, mildew, stains, etc. But even with routine maintenance, you may begin to see and feel a white, chalk-like residue when running your hand over the siding surface. This is caused by oxidation that occurs when the polyvinyl chloride (PVC) is exposed to oxygen, catalyzed by humid, damp or wet weather. Oxidation is the first sign that the material is breaking down and is unfortunately inevitable in siding’s aging process.
Some experts recommend painting to improve the surface and slow the oxidation process (check with the manufacturer to make sure painting doesn’t void the warranty). While this intervention can buy you some time, at some point replacement will be necessary to ensure siding continues to protect the home’s exterior and that its deterioration doesn’t lead to interior problems such as moisture infiltration of your walls and more.
