Wet & Forget - FAQs

Can I use Wet & Forget safely on ANY exterior surface?

Sure can - absolutely ANY exterior surface.  This one product cleans them all!  There's no need to buy separate products for all these varied surfaces!

Great for all types of Roofs including Decramastic, Clay tile, Concrete tile, Super 6, Fibrolite, Colour steel, Zincalume (iron roof)
    • Asphalt (Blacktop)
    • Astroturf
    • Bowling greens
    • Butinol
    • Bricks & paving
    • Canvas tents
    • Caravan awnings
    • Concrete
    • Cow sheds
    • Driveways
    • Fibreglass boats
    • Fibreglass hulls/topsides
    • Fibrolite cladding
    • Flexipave
    • Glass/Plastic houses
    • Glass houses
    • Golf greens
    • Grouting
    • Hinuera stone
    • Inflatable dinghies
    • Limestone
    • Hockey pitches
    • Oamaru stone
    • Marble
    • Outdoor furniture
    • Outdoor pots
    • Paintwork
    • Paths
    • Patios
    • Patio furniture
    • Plastic houses
    • Pool surrounds
    • Shade sails
    • Solar Panels
    • Tennis courts
    • Teak decks
    • Textured finishes
    • Tiles
    • Timber decks
    • Tombstones
    • Umbrellas(outdoor)
    • Vinyl cladding
    • Weatherboards
    • Yacht dodgers/sails


    Will Wet and Forget affect my pets?

    Not under normal circumstances, but normal safety precautions prevail. Keep your precious pets off the surfaces until the surface is TOTALLY DRY.  This prevents the cute little critters licking product off their fur or paws.  We say "Don't let your moggy or Doggy's paws get soggy!  If they accidentally walk or sit in the product - wash their feet and bottoms with fresh water as a precaution.  


    How do I apply Wet and Forget?

    1. Mix the product 1 part Wet and Forget to 5 parts of water - in a garden sprayer. (eg 1L Wet & Forget to 5L water)
    2. Choose a cool dry day to apply it.
    3. Saturate the dry surface with the product.
    4. NO rain for the first 5 hours
    5. Then, just watch it come cleaner, bit by bit as Mother Nature takes over. The weathering process gently takes the decomposing material away bit by bit without scouring the surface it has infested.
    6. Only one application!


    What time of the year do you apply Wet and Forget?

    There is no definitive time - but of course all these growths such as lichen, moss, mould and algae appear more in the winter months when the exterior surfaces are damp and wet which are the perfect conditions for these growths to thrive. The best time to apply Wet & Forget is when you see the first signs of green. Always apply to a DRY surface so you do need to wait for that right day. If you can stop it at the green stage, then the cleaning is so much quicker than when the surface is black - which is a sure sign that the contamination has been there for a much longer time. Be proactive and get rid of it at the first visible sign.


    Do you need to rinse off Wet & Forget?

    NO. Apply Wet & Forget to a dry surface and then just leave it. Mother Nature takes over as the contamination breaks down and the weathering process takes it away gently, bit by bit until the surface is clean. If you rinse - you will dilute the product and the results will not be as expected.


    Is Wet and Forget a bleach?

    Absolutely not!


    What is the shelf life of Wet and Forget?

    Unlike bleach based cleaners, Wet & Forget has an unlimited shelf life.


    What is the difference between Wet and Forget and Rapid Application?

    They are 'sister' products.  The ingredients and coverage are the same but the dilution rates are different because the way you apply them is different.  Wet and Forget needs a garden sprayer while Rapid Application needs just a hose to apply.
    Rapid Application and Wet and Forget give you the same coverage

    Is there any residual effect if I use Wet and Forget?

    Some of the ingredient remains active if the surface is porous. This helps prevent premature recontamination.


    If I am on tank water, can I use Wet and Forget on my roof?

    Sure can. But you must disconnect the water supply to your water tank for 3-4 weeks or have at least 36mm of rain to remove the concentrate from your water tank. Wet and Forget has been used for over 35 years to treat biological growth on roofs and you don't want the decomposing debris to get into your tank water.


    How do I apply Wet & Forget?

    You only need a garden sprayer and mix the product up 1-5.


    Can I change the specified ratios given in the instructions for Wet & Forget?

    Yes. If the contamination is extreme, increase the strength for a quicker reaction. However, if you have cleaned the surface previously with Wet & Forget and you want to give it just a maintenance spray, you can decrease the strength if the contamination is light. The cleaning process will still be just as effective.


    Do I have to use Wet & Forget all at once?

    No, but good planning is essential. Work to a pattern so you know where you have started and stopped. The product is fine if left in the spray container as it does not deteriorate when it has been diluted. Plus it will not damage your garden sprayer as the product is not corrosive.


    How long will Wet & Forget last in the container?

    Wet & Forget has unlimited shelf life. Always keep the cap done up tightly and the container out of reach of children.


    How long does it take Wet & Forget to work?

    It is totally dependent on the intensity of the contamination. If it is really light you will see results within days. Otherwise it may take approximately 2-3 months to see improvements. Your concrete may turn an orangey brown when the Wet & Forget is applied. This is normal and shows you have had a good reaction. The discoloration will dissipate over a short period of time and is not permanent. The good news is that when you use it again the following season, the clean up will occur within weeks. In the very worst case scenario where contamination is extreme, it may take 6-12months.


    What is the dilution rate and coverage area of Wet & Forget?

    Dilute Wet & Forget 1 part to 5 parts water. Every 5L pack yields 30L of product to spray. With this, you will get coverage of between 100-300m2 depending on the porosity of the surface. ie painted surfaces will use less product but porous surfaces readily absorb the product and therefore coverage could be in the range of 100-150m2


    When is the best time to apply Wet & Forget?

    On a cool, dry windless day and when no rain is expected for 4-6 hours. Often the evening is best when evaporation of the product is minimal. This will ensure that the surface to be treated stays wet with Wet & Forget for an extended period.


    Will Wet & Forget damage my plants?

    Not unless you are directly spraying it onto the plants. If you accidentally do this, then rinse the plants down with water from the hose. Or better still, protect them with paper or plastic to avoid overspray.


    Will Wet & Forget remove the mould off my timber decks?

    Most definitely! But if your deck is older and has never been cleaned, it may be noticeably blackened with the contamination. In this case, it would be advantageous to wait a month after the application of Wet and Forget and give the area a light brush with a broom or scrubbing brush with warm water to remove it. The good news is that you should only have to do this once and then the maintenance becomes so easy.  Also check out our other amazing product, Hit The Deck,  for a more instant result (although it does involve more elbow grease!)


    Will Wet & Forget get moss out of lawns?

    Sure will! Firstly lightly water the lawn but not enough to saturate the moss. Do this late in the day when the sun is low so that evaporation is kept to a minimum. Dilute the 5L Wet & Forget 7 parts water to 1 part Wet & Forget and spot spray the moss. You may have to give it a couple of goes until you have it under control. At worst you may get slight burning on the grass but it will recover very quickly. Rake the dead moss out. then sprinkle lime over the area as this is usually a sign that your pH of the soil is not quite right.


    How much Wet & Forget will I need to clean my roof?

    The average 3 bedroom tile roof is approx 150m2 but because of the undulations of the tile profile the actual area is a lot bigger. Therefore an average tile/concrete roof would require 2 x 5 litre packs, depending on how porous the surface is and how much biological growth is present. For an average 3 bedroom tile roof with lichen you would require 3 x 5 litre packs depending on the total area covered with lichen.

    For Lichen removal:
    For best results mix the Wet & Forget and spot spray the lichen, leave for 10-15 minutes and then respray the lichen and the entire roof to ensure the plant absorbs the Wet & Forget thoroughly. The first application is to dissolve the waxy surface. The 2nd spray will then penetrate the lichen.
    For green moss and black mould:
    For green moss and black mould one application is normally sufficient.