Should windows and window/door frames be masked when soft washing?

November 02, 2019

Should windows and window frames be masked when soft washing?
Benz Lightning Cleanze softwash biocide based on sodium hypochlorite (SH)

A customer asked us: "A surveyor has specified the soft washing of render with Benz Lightning Cleanze and to mask the windows. What is your experience of masking windows and window frames when applying Lightning Cleanze at 5:1 on render, with some overspray and run-off inevitably going onto the windows and frames?"

We replied: We've never masked windows and have never experienced any long-term issues with window frames or glass.

In hot weather the glass can look unsightly for a very short time until you rinse off with de-ionised water but our softwash products have never caused any damage.


Quick tip: A temporary colour change can occur on white uPVC – for example on certain window and door frames, facia, and soffit – in hot weather and strong sunlight.

This is caused by the increased reactivity of Lightning Cleanze when exposed to heat and direct sunlight. The uPVC will return to normal after 2 to 48 hours, depending on the strength of your mix.

To stop this happening we have a hosepipe or pressure washer with rinsing nozzle on hand ready to immediately rinse off any product that gets on the frames..

Our advice is to treat a small, out of the way, test area of a window and window frame. Then show the surveyor and explain that this is all that will result from overspray onto the frame.


Quick tip: If the surveyor insists on using masking tape, then check the windows and frames will not react to it. Also, in my experience of painting houses, it is best practice to get the tape off as soon as possible because the adhesive can bake onto the frames in hot weather and it can be extremely difficult to remove.

We hope this information is helpful and sincerely wish you great success in your soft washing business,

Ben, Leo, Fiona, Stevie & Anthony

PS: After completing the first softwash treatment of a property, put your customer on a "Clean & Maintain" ongoing maintence programme.

Your customers will enjoy a permanently clean property and you, the contractor, will enjoy a steady stream of repeat business. A win-win arrangement for everyone.

Click here to explore the full range of Benz softwash cleaning products

Benz Softwash Bio Cleanze DDAC biocide & Benz Softwash Lightning Cleanze SH sodium hypochlorite biocide

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