In the bathroom, kitchen and other areas of the house, silicone and polyurethane foam, also known as expanded polyurethane, have long been the most commonly used insulators and sealants. But it can happen that windows and window frames are stained with silicone residue and stains that are very difficult to remove.
Using sharp tools to cut off the residue may be effective for thick pieces of silicone, but have no effect on stains - while running the risk of damaging the glass or window frame with a scratch which is not only as unsightly as the silicone itself, but cannot be removed.
The best way to resolve the problem of silicone stains on glass and window frames is to use a specially formulated product like ZERO SIL*.
Removing silicone and polyurethane foam residue and stains from glass with ZERO SIL
Apply ZERO SIL undiluted over the entire silicone residue on the glass, leave it to act for 20 minutes, then scrape it off with the spatula included in the kit. You can then pick up the residue with paper towel or a cloth.
*check product availability in your market