Soft washing leaded glass windows (leaded lights)

August 05, 2023

Soft washing leaded glass windows (leaded lights)

A customer told us that he soft washes houses with lead strips glued on to the windows – to look like olde leaded lights.

He asked, "Will Benz LIghtning Cleanze discolour the lead, or, worse, make it come unstuck from the window glass?"

He had found, correctly, that it was inevitable that some softwash product will get on the windows whilst treating the surrounding walls.

And he also asked, "Is there any known discolouration of lead when using Benz Bio Cleanze?

We told him that we know of no problems regarding Benz Bio Cleanze and lead.

There is a possibility that a strong dilution of Lightning Cleanze could discolour the lead. But that will usually reverse over time through natural weathering, or by post-treating with Benz Oxy Cleanze.

Any propensity for discolouration can be mitigated by immediately pre and post rinsing the leaded lights with fresh water, ideally de-ionised.

In our experience neither product has had any negative effect on the glue. The glue will be designed to withstand harsh weather, salt and cleaning products.

So unless the windows were to be very heavily saturated with soft washing chemicals, which are then aggressively brushed in, or pressure washed, we don't foresee a problem.

Quick tip: As always, if you are in any doubt about the wisdom of applying one of our softwash chemicals to a surface, with your customer's permission treat a small test area first.

Another sensible precaution is to reduce spray drift by skillful application techniques and choosing the correct Benz softwash spray nozzle.

Using a soft brush to apply our softwash products around the window reveals is another way to mitigate the risk.

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

Benz Team

Click here to get more practical soft washing how-to tips

How to find answers to most soft washing questions: Simply enter a relevant "keyword" or short phrase – e.g. keyword for the above link = "how to" – into our in-site Search Engine (magnifying glass icon on the main menu).

Click here to download our Product Documentation Pack (includes Application & Dilution guides, SDS, PDS, RAMS, PPE & Mask info, COSSH, sample Contract and more)

Order Benz Softwash chemicals & equipment online or by phone:

GB (England, Scotland, Wales)

Phone: 0800 70 74 222 


Ireland and other countries

Phone: 00353 214 622 978


Lines open Monday - Friday, 9am – 5pm

Please note: The above numbers are for orders only (click here for tech support)

PS: Click here to set up your "Clean & Maintain" programme
. After completing an initial soft wash treatment, put your customer on a "Clean & Maintain" ongoing maintenance programme. Your customers will enjoy a permanently clean property and you will enjoy a steady stream of repeat business.

This is clearly a win-win arrangement for you and your customers.


Click here to explore the extensive range of Benz softwash cleaning chemicals & equipment

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

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