Do not add bleach to Sugar Soap
Can I add bleach to Selleys Original Sugar Soap to clean mould, dirt and grease off walls and ceilings?
No. Do not add bleach — or any other product — to Selleys Original Sugar Soap. Selleys does not recommend mixing anything into it.
If the Sugar Soap has not removed all the mould or grease, you can use a bleach-based cleaner afterwards. But the two must never be mixed, and the surfaces must be rinsed thoroughly before you apply the second cleaner. Rinsing is not a formality here — it is the step that keeps the two chemistries apart on the wall as well as in the bucket.
For mould specifically, Selleys recommends following up with Selleys Rapid Mould Killer for effective eradication.
Why mixing cleaners is the wrong move
Selleys Original Sugar Soap is a professional-strength alkaline cleaner with a pH of about 11. Its own directions tell you how to dilute it — half a cup into half a bucket, 5 litres, of water — and to dilute to suit the task. Nothing in those directions involves adding another cleaning product, and the recommendation not to is unqualified.
Selleys Rapid Mould Killer carries the same instruction from the other direction: do not mix it with other cleaners, as this may cause adverse reactions. Two products, two data sheets, the same rule.
There is also a practical reason the mixture does not help. Sugar Soap is a grease and grime cleaner; it lifts the soap film, body oils and airborne kitchen grease that mould feeds on. Rapid Mould Killer eradicates the mould. Diluting either into the other gives you a weaker version of both rather than a stronger version of anything.
The right sequence
- Clean first with Selleys Original Sugar Soap. Dilute half a cup into 5 litres of water, and use a mop or cloth — a Selleys Super Cloth is ideal. For stubborn or in-ground marks it can be used neat with a non-scratch scouring sponge or cloth such as a Selleys Wash Up Wiz.
- Rinse thoroughly. Keep a bucket of clean water and a clean cloth or mop beside you and wipe the surface down. This is the step that must not be skipped before any second product goes on.
- Then treat the mould. Spot test Rapid Mould Killer on an inconspicuous area first, twist the nozzle to SPRAY or STREAM, spray the affected areas, leave for 2 to 3 minutes, then rinse, wipe or scrub off.
Working in that order also gets better results than treating the mould first. A mould killer applied over a greasy wall spends its contact time on the grease rather than on the growth underneath.
Safety — particularly overhead
Selleys' advice on this question is specific: if you are spraying areas above your eyeline, wear protective eyewear so the spray does not enter your eyes. Ceilings and high wall sections are exactly where this applies, and a fine spray coming back down is easy to underestimate. Read the pack for further safety instructions before using.
Selleys Original Sugar Soap's own safety directions warn that it causes serious eye irritation. Keep it out of reach of children, avoid contact with skin and eyes, wear rubber gloves if you have sensitive skin, and wash your hands after use. If it does get in your eyes, rinse thoroughly with water.
Where Rapid Mould Killer should not be used
Its data sheet lists surfaces to keep it off:
- Fabric
- Mirror tiles
- Metallic surfaces
- Older baths or basins
On some matt finish tiles, and in hard water areas, staining may occur — which is why the spot test on an inconspicuous area comes before the job, not after it.
Where Sugar Soap should not be used
- Wipe it off immediately from aluminium and brass surfaces. It can tarnish or discolour bare brass and aluminium.
- Rinse it well from glass before the product dries, or it leaves a hard salts deposit that is difficult to remove.
- Test an inconspicuous area for compatibility and colourfastness if using it on clothing, carpet or upholstery.
If the mould keeps coming back
Cleaning the visible growth off a wall does not change the conditions that produced it. Selleys' answer on removing mould under eaves makes the point directly: Sugar Soap cleans visible mould off, but it does not kill the spores, so where conditions suit mould growth the mould may return. That is why the follow-up treatment matters, and why ventilation and moisture control matter more than either product. For the wider problem see how to eliminate mould in your home and, for wet areas, how to get rid of bathroom mould.
Common questions
Can I add just a small amount of bleach?
No. Selleys does not recommend adding any other product to Selleys Original Sugar Soap.
Can I use bleach at all, then?
Yes, as a separate step. Use a bleach-based cleaner afterwards, never mixed with the Sugar Soap, and rinse the surfaces thoroughly in between.
What does "rinse thoroughly" mean in practice?
Wipe the surface over with clean water and a clean cloth or mop until no cleaner remains, then let it dry before the next product goes on.
Will Sugar Soap kill mould on its own?
No. It cleans visible mould and mildew off the surface but does not kill the spores, which is why Selleys recommends a follow-up treatment with Rapid Mould Killer.
How long does Rapid Mould Killer need to work?
Spray the affected area and leave it 2 to 3 minutes, then rinse, wipe or scrub off. Spot test an inconspicuous area first.
Do I need eye protection?
Yes, when spraying above your eyeline. Selleys Original Sugar Soap also carries a warning that it causes serious eye irritation, so eye protection is sensible whenever you are working overhead.
Can I mix Rapid Mould Killer with another cleaner to make it stronger?
No. Its data sheet says not to mix it with other cleaners, as this may cause adverse reactions.
What dilution should I use for walls and ceilings?
Half a cup of Selleys Original Sugar Soap into 5 litres of water for most jobs. Dilute to suit the task, and use it neat only for stubborn or in-ground marks with a non-scratch scouring cloth. See also preparing ceilings for painting.
Can I add bleach to Selleys Original Sugar Soap to clean mould and grease off walls and ceilings?
No, Selleys does not recommend adding bleach or any other product to Selleys Original Sugar Soap. Mixing products can create safety hazards and unpredictable results.
What should I do if Selleys Original Sugar Soap doesn't fully remove mould or grease?
If Selleys Original Sugar Soap isn't removing all the mould or grease, you can use a bleach-based cleaner or a specialized mould product like Selleys Rapid Mould Killer afterward, but never mix it directly with the sugar soap.
Do I need to rinse the surface before applying a bleach-based cleaner after using sugar soap?
Yes, you should ensure thorough rinsing of the surface with water before applying another cleaner, such as a bleach-based product, after using Selleys Original Sugar Soap.
What product does Selleys recommend for effective mould eradication as a follow-up to sugar soap?
Selleys recommends using Selleys Rapid Mould Killer as a follow-up product for effective mould eradication if sugar soap alone isn't sufficient.
What safety precautions should I take when using bleach-based cleaners on ceilings or areas above eye level?
When using bleach-based cleaners or spray applications on areas above your eyeline, you should wear protective eyewear to prevent spray from entering your eyes and read the pack instructions carefully for all safety information before using.
What is the recommended step-by-step process for cleaning mould and grime with sugar soap and bleach-based products?
The best practice approach is: 1) Clean with Selleys Original Sugar Soap first, 2) Rinse thoroughly with water, 3) Apply a bleach-based cleaner or Selleys Rapid Mould Killer if needed, and 4) Allow the products to work independently rather than mixing them together.
Why does Selleys advise against mixing sugar soap with other cleaning products?
Selleys advises against mixing sugar soap with other cleaning products because doing so can create safety hazards and produce unpredictable results.