How to soft wash headstones & gravestones

In most cases, we would recommend Bio Cleanze for cleaning headstones and gravestones. It is particularly well suited to compatible natural stone because it works gradually, treating the biological growth without the need for aggressive pressure washing.

Apply Bio Cleanze after completing a successful test patch and allow it to work over the following weeks and months. This is often the most appropriate approach for older or more delicate memorials, where trying to create an instant result can do more harm than good.

The important thing is to identify what you are working on before you begin. Headstones can include porous natural stone, polished granite, marble, old mortar repairs, lead lettering, painted inscriptions, ceramic photographs and decorative metalwork. Do not assume that a treatment suitable for the main stone will also suit every detail on the memorial.

Before you start

Confirm that the person commissioning the work has the authority to do so, then check whether the cemetery, parish, local authority or grounds manager also requires permission.

Inspect the memorial carefully and take photographs before beginning work. Look for cracks, flaking stone, loose sections, failed joints, leadwork and fragile decorative details.

Very old, listed, damaged or historically important memorials should be referred to a qualified stonemason or conservation specialist before treatment.

Using Bio Cleanze

Bio Cleanze is a spray-and-leave treatment. It penetrates the surface, treats algae, fungi, lichen and other biological growth, then allows the weather to continue the cleaning process naturally.

This is not an instant clean. You may see early signs of change within days, but heavier growth can take weeks or months to release fully. That slower result is often preferable on a headstone, particularly where the stone is weathered or the lettering is old.

Use a manual or battery-powered backpack sprayer where possible. It is simple, quiet and allows you to apply a controlled amount of correctly diluted treatment directly to the memorial.

When Lightning Cleanze is appropriate

Lightning Cleanze can be used where the stone is compatible and the customer requires a faster result.

A 5:1 dilution will clean many suitable stone headstones. Apply carefully, allow a suitable dwell time and rinse thoroughly with clean water. On compatible polished or non-porous memorials, 10:1 may be enough, but always complete a test patch first.

Do not apply Lightning Cleanze to lead lettering, lead detailing or sensitive metals. Protect them from contact, and rinse immediately if any overspray occurs.

Where the stone is porous and suitable, Lightning Cleanze can be used for the initial clean, followed by Bio Cleanze once the memorial has been rinsed and dried. This gives the customer a cleaner result straight away, while Bio Cleanze helps slow the return of biological growth.

Do not rely on pressure washing

Aggressive pressure washing is rarely appropriate for headstones. It can remove loose surface material, damage old mortar, erode lettering and force water into cracks.

If a rinse is needed after Lightning Cleanze, use the gentlest effective method. A low-pressure rinse with a wide fan jet is normally more than enough. Keep the nozzle moving and stop immediately if the stone begins to shed, flake or show signs of erosion.

Protect lettering, flowers and nearby graves

Lead lettering, painted inscriptions, ceramic photographs and decorative inserts all need separate consideration. Protect them before treatment and do not rely on a test patch on the stone alone.

Remove flowers, wreaths and ornaments from the immediate area only with permission. Pre-wet surrounding grass and plants where appropriate, control spray carefully and avoid allowing concentrated run-off to enter flower beds or travel onto neighboring graves.

Return anything you have been authorised to move to its original position, and leave the grave and surrounding area clean and undisturbed.

Headstone cleaning checklist

• Confirm authority and cemetery permission.
• Inspect and photograph the memorial.
• Identify the stone, lettering and decorative materials.
• Complete a test patch.
• Use Bio Cleanze as the preferred gradual treatment for compatible porous stone.
• Use Lightning Cleanze only where a faster result is needed and compatibility is confirmed.
• Protect leadwork, lettering, flowers and nearby graves.
• Avoid aggressive pressure washing.
• Leave the area clean, tidy and respectful.

We wish you the best in your softwashing business,

Team Benz

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