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1) Are Benz soft washing chemical products fully approved and legal?
Yes, Benz Biocidal Wash and Benz Blackwash are fully approved by the Pesticide Control Service (PCS) and the Department of Agriculture and Marine in Ireland, and the Health & Safety Executive (HSE) in the UK as meeting all EU health, safety, and environmental protection standards.
Benz Blackwash is applied diluted and is "unclassified" because our formula allows the use of very low levels of sodium hypochlorite.
As far as we know Benz Blackwash is the ONLY fully legal sodium hypochlorite based soft wash biocide available in the UK and Ireland.
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6) Are Benz soft wash biocides safe for use on building materials?
Yes, When used as directed on the label and following the application instructions on this website, they are safe for all known building materials used in walls, roofs, decking, fencing, and paths – including concrete, tarmac, render, timber, aluminium, and slate.
Always treat a small, obscure test patch – and get your customer's approval of the result – before treating a material you have not treated before or are in any way unsure of.
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8) Are the Benz payment and data protection systems secure?
Absolutely. We use the world's leading ecommerce website provider – Shopify – to create the site you are reading. Our website uses SSL (Secure Sockets Layer) certification, which you will see upon checkout, and is Level 1 PCI DSS compliant.
Along with millions of reputable business we use the SSL protocol to ensure the highest level of security for your online transactions.
We also offer the world's leading online secure payment system – PayPal – to process transactions, enabling you to safely and easily pay using your PayPal account or your credit card.
All this means you can purchase from us safe in the knowledge that all your personal, business and financial data will remain secure and confidential.
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9) Do you offer reduced prices if I buy in quantity?
Yes. Click the links below and select the quantity you want from the price-quantity dropdown menu to view the substantial discounts for bulk purchases:
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10) What uses are Benz soft washing products intended for?
They treat and control the root cause of unsightly red, black, and green staining on walls, roofs, tarmac, concrete, timber decking & fencing, children's play areas, tennis courts and paving. This staining is caused by biological growths such as red algea, green algea, black and yellow lichen, mould, and fungi that are not only unsightly but can damage the actual structure of property.
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12) How long does Benz Biocidal Wash take to act?
The biocide starts to act immediately and usually begins to show results from 24 hours to 14 days although it can take longer.
The rate of cleansing will vary with every job depending on the prevailing weather, age and thickness of the biological growth, and so on. The cleansing process will continue for several months and is usually complete within a year.
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13) What happens if it rains during or after application of a soft wash biocide?
If it rains during or immediately after treatment, wait for the rain to pass and then re-apply with a slightly stronger mix to allow for dilution by the rain. There's no need to let the surface completely dry out before second application as the combined strength of the two applications will be sufficient.
This assumes the rain is not torrential, in which case it would be best to leave the job and come back when it is dry. But in practice this is rarely a problem. Just keep an eye on the weather forecast and trust your judgement.
As a rule of thumb allow a few hours of dry weather following application for Benz Biocidal Wash to soak deep into the biological growths and surface (if porous). Benz Blackwash only needs 60 minutes to fully work, so rain is not so much of an issue.
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18) Does Benz Biocidal Wash permanently prevent the return of biological growth?
No biocide, or any other treatment, can prevent the eventual return of biological growth. But Benz Biocidal Wash has a "residual biocide" effect that means regrowth is massively inhibited. Neither power washing nor bleach offer this residual effect.
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21) How long does a soft wash treatment by Benz Biocidal Wash last before needing re-application?
Self-draining surfaces like rendered walls and roofs will often stay clean for 3 years or more before regrowth requires another treatment.
Horizontal surfaces like patios, decking, drives, and footpaths stay damp longer and so regrowth happens more rapidly. These will usually require an annual or bi-annual treatment to keep the growth under control and the property looking great all year round.
We've found that horizontal treated surfaces can look good for a up to two years as long as there is good exposure to wind and sun, and organic matter such as leaves falling from overhanging trees – and flower pots that overflow when it rains – is kept under control.
If organic matter is left on the surface, and sometimes this is unavoidable, a yearly application of Benz Biocidal Wash may be needed.
25) How do you explain to a customer that results from Benz Biocidal Wash are not immediate and can take a few months to show the full effect?
We always tell our customers from the outset that “results will be seen within 24 hours to 14 days and the self-cleansing process will continue for up to a year”. And we've never had a problem.
On a large job you could split the price 80/20. Charge 80% at the time of the first application and the remainder following a very light application after two or three months. Customers are usually very happy about this as it spreads the cost. It also gives you a chance to take photos for your website and catch any missed bits.
Alternatively first treat with Benz Blackwash to give customers an "instantly clean" effect, and use Benz Biocidal Wash to keep their property clean.
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26) Is the active ingredient in Benz Biocidal Wash DDAC (Didecycldimethy-Lammonium Chloride)?
Yes. We have Benz Biocidal Wash manufactured by a leading European chemical company who have an excellent reputation for working to the very highest quality standards.
There are other sources of this chemical but they are not approved for use by the Irish, the UK, or EU government authorities. They are of inferior quality and may contain impurities that contravene Health and Safety legislation plus open the user to the risk of damaging building materials. Some contain high levels of sulphur and may cause burns, which is obviously a severe Health and Safety hazard.
Insurance companies may not cover the use of unapproved chemicals, which obviously could work out very costly indeed as the contractor would be liable if anything was to go wrong when working on a customer’s property.
But when you use Benz Biocides you can rest assured that they come from highly reputable sources, are manufactured to the most stringent standards, and conform to all EU, Irish and UK Health and Safety legislation.
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28) Does DDAC biocide kill wet and dry rot – including on decking?
Yes. DDAC kills the fungi responsible for dry and wet rot as well as helping to clear surface blemishes, thus preserving the structure of the wood as well as it’s appearance.
Keeping timber free from biological contamination is essential for it’s long-term maintenance as all exposed timber is at risk of algae and black mould attack.
If a customer wants to maintain the grey colour of a natural wood surface the best approach is to apply a DDAC wood preservative immediately discolouration appears.
This is also an excellent way to preserve wood without polluting the environment.
Warning: If decking has become slippery, a brushing – or light power wash – will be necessary prior to treatment with a DDAC biocide wood preservative. Ongoing annual or bi-annual treatment will maintain the decking (the time scale for re-treatment depends on location, environment and prevailing weather).
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29) Why would I buy Benz Biocidal Wash when there are apparently cheaper products on Amazon?
At first glance Benz Biocidal Wash may appear similar to products available to the public via Amazon and other retail outlets. But the comparison can be like comparing apples and bananas – they may both be fruit but other than that they are very different.
In reality these products are very weak, usually containing only 5-10% active ingredient (DDAC).
There are also a few slightly stronger products being sold that on closer inspection will show to be “industrial technical grade” only. They are not the same as Benz Biocidal Wash as they do not carry Pesticide Control Service (PCS), Irish Department of Agriculture and Marine, or UK Health and Safety Executive (HSE) approval for use as a biocide. And are therefore illegal for commercial use.
Also, the grade of active ingredient may be low and it may have been contaminated during production.
In contrast Benz Biocidal Wash is fully approved and contains a full 50% DDAC as active ingredient. This makes it more effective and far less expensive than any other product we know of. It is also completely legal and government approved.
This cost-effective price makes it an ideal choice for post-treatment following pressure or power washing. Click here to take a look at the graphs and our test results to see the difference between conventional power washing without follow-up treatment, and those obtained after a post-treatment with Benz Biocidal Wash.
Other important points to consider when deciding which soft washing biocide to buy:
Q: My customer noticed plants starting to die where we treated walls. Is there anything I can say to reassure the customer?
A: Did you pre and post drench the plant life and cover them to protect from over-spray?
Check your application technique as you need to be aiming for as little over-spray as possible, for safety of plant life and the operator. If there are flowerbeds that could receive run-off into the soil then divert the run-off into a foul water sewer.
Hopefully it is just some foliage damage from over-spray, in which case the plants will recover quite quickly.
In future pre-drench vulnerable areas of plant life with water first and rinse immediately after treating. If working in high heat have another operator rinse while the application is in progress.
Q: Which of your biocides will clear black lichen spots from both natural stone and block paving?
A: Benz Blackwash at 5:1, well brushed in, left to work for 60 minutes, followed by light power washing will lift the majority of the lichen. Repeat if necessary.
Once reasonably clean, thoroughly rinse and treat with Benz Biocidal Wash at 25:1, which will continue the cleaning process over the next few months. Explain this to the customer beforehand as having their property self-cleanse over time is not something most people are used to.
Q: How long should we leave before rinsing our soft washing equipment and before damage could occur to our soft washing equipment?
A: Depends on the quality of the fittings you have. Some fittings will not be suitable for prolonged exposure to soft washing biocides. We recommend rinsing immediately after completing work on a contract and/or at the end of the day.
Q: How do I rinse a roof that I cannot see properly?
A: We favour both applying soft washing biocides and rinsing high roofs from ladders secured by Tetra level 2 or 3, scaffolding, or a Cherry Picker. We nearly always include the cost of aluminium scaffolding for roofs that require soft washing with Benz Blackwash and rinsing. It is safer and you can do a better job working from the eves.
Q: Will Benz Blackwash successfully clean garage doors, painted, plastic on metal (i.e. roller door)?
A: Absolutely but always do a test patch first and get your customer’s approval of the result before treating the entire surface. Treating with Benz Blackwash at 10:1 would be the preferred dilution.
Q: How long before Biocidal Wash has an effect on a surface, whether that surface be block paving or roof tiles?
A: Benz Biocidal Wash works within minutes to kill all algae, lichen, fungi and mould. Then the self-cleansing effect can be seen in 24-48 hours with more dramatic results seen in weeks or months depending on the prevailing weather, local environment and the type of surface. Lichen are the most troublesome and can take 6 months to a year to go from a roof or drive. Red, green, light black on render will usually disappear in a few weeks.
Q: How long does Benz Biocidal Wash last on a) roofs b) driveways?
A: It depends on the location and prevailing weather. Some roofs, if pre-cleaned properly before given a soft washing treatment, can last up to five years before signs of re-colonisation appear.
But if there are tall trees near by, for example, the surface may need re-treating annually.
We to tell our customers to allow 1-3 years before a maintenance treatment may be required for the majority of roofs.
Paths and drives will usually require an annual maintenance treatment of Benz Biocidal Wash as they retain damp and attract more organic matter such as leaves and mud.
A maintenance treatment is less labour intensive than a full clean, therefore costs less, and will keep surfaces looking great all the time.
Q: What techniques can I use to help prevent unintentional streaks to surfaces my customer has not employed me to clean?
A: Reduce the run off to areas using spray techniques like low flow rate application, brushing the surface and using the correct Benz nozzle or foaming nozzle. Pre and post wetting is the most common method.
Q: We are hesitant about using Benz Blackwash for cleaning UPVC. Is it possible to produce a thicker “foam”, so the soft washing chemical sticks to the surface and minimises run off and streaking of untreated surfaces?
A: Yes, the Euro-foam High Performance Soft Washing Nozzle does just that. It’s available via Eurojet.
Benz Blackwash is great at cleaning UPVC and PVC and is especially suited to very heavily soiled areas. However it does require special handling and attention in use so if you not confident or experienced, a different UPVC cleaner may be indicated.
Also, pre and post wetting will reduce the incidence of streaking, as would brush application. The brush application soft washing method produces more of a foam but is slower to apply.
Q: Is soft washing as simple as spraying Benz Blackwash onto render with a Benz soft wash spray nozzle and then washing it off with a water fed pole?
A: Yes and no.
Simply put the process of soft washing is to apply Benz Blackwash and rinse off. You can also use Benz Biocidal Wash as a post-treatment or stand-alone cleaner.
But be aware that there are a number of health and safety considerations and other factors a professiona soft washing contractor who values their reputation should be aware of.
Please read and watch the soft washing information on this website so you can work both effectively and safely. We’ve also published a soft washing how-to manual that leads you step-by-step through many of the ins and outs of soft washing.
Q: Is there specific hose I need that is resistant to the chemicals?
A: You can use most types of hose to get going as most offer a certain level of resistance, especially if regularly rinsed through after completing soft washing. Standard 8mm microbore window cleaning hose holds up well and does not kink. If you were buying a new system then chemical resistant hose should be supplied with the system.
Q: How do I use your soft washing products to soft wash roofs in high summer heat?
A: Cool the surface by spraying it with water first and keep it wet whilst the soft washing product works, using another operator to cool spray if necessary. If this is not practical do the spraying in the cooler times of early morning and late afternoon.
Q: Am I allowed to say that on my website that I'm using Benz soft washing biocides and list some of the uses and benefits of using Benz biocides?
A: Yes, please do.
Q: I have a white Harling wall that is discoloured. Which product would be more suitable – Blackwash or Biocidal Wash?
A: Both would work. Blackwash will give instant results but depending on the amount of colonisation and porosity of the surface may need an application of Biocidal Wash as well to kill remaining spores. Biocidal Wash will work if is only red and green staining and has the advantage of being a spray once and walk away treatment, which saves time on application. If there are lots of black marks you will need to use Benz Blackwash.
Q: I treated a test patch but my customer is still unsure as there are some brown marks that are although faint the are visible. What your advice on this?
A: You’ll find that most of the marks will fade over time. The surface often comes up better when using a pressure washer with a rinsing nozzle, or set to low pressure and attaching a fan jet, to rinse. Tell your customer that this is the best system to clean their property without using aggressive power washing or harsh chemicals.
Q: Will lead flashing turning brown when exposed to Benz Blackwash?
A: Use Blackwash at 5:1. Pre-wet the lead and rinse immediately following treatment. If possible have another operator rinsing whilst you are applying. Keeping the lead cool and rinsed is especially important when applying in hot conditions.
Q: How do I reduce chemical run-off when soft washing?
A: To reduce run-off from surfaces try these techniques:
1. Use a low flow rate and spray from the bottom up - this reduces runs dramatically.
2. Use a brush with fan jets. Use a low flow rate and take your time.
3. Plan when you are going to use Benz Blackwash. Temperature affects Blackwash's oxidising properties so early morning or later in the afternoon or early evening are the best times to apply.
Q: Will Blackwash remove the marks left on render after ivy has been removed?
A: We've had mixed results depending on the variables of different contractors. The Blackwash will remove many of the marks left behind and we've found a light pressure wash with a wide angle jet when rinsing also helps.
It all depends on how well attached the ivy is. Sometimes the vines are stuck to the render in which case leaving for a period of time and then brushing off and/or light pressure washing is the only option.
To do a perfect job, cut the ivy at the root. Then separate what remains on the wall from the root by cutting out a short section. This means the ivy on the walls will die and naturally begin to separate from the walll, diminishing the danger of damaging the surface by ripping it away.
Then dig out and remove the roots, or kill them with weedkiller. As the ivy on the walls dies off and naturally falls away through time, what remains can be brushed off or lightly pressure washed.
A: Here's the facts, direct from KRend (not information picked up from online forums, which can often be misleading, confusing and outright wrong in our experience).
1) KRend can be painted but it requires great care at the preparation stage. Worst case scenario is that spores can get trapped under the layer of paint and of course will breed. A high quality masonry paint is essential.
2) KRend's recommended paint supplier is Rendit. Phone 01302 884385. They specialise in render paints and can also match KRend colours. These would be the people to recommend to your customer if they want to buy paint.
3) KRend's official guidance on preparation: Surface must be thoroughly cleaned and washed down. All biological growth must be removed and treated with biocide.
So if your customer insists on painting (perhaps they just want a change of colour for reasons of their own) then they MUST remove all algae and other biological growths and treat the surface with biocide before painting.
So you can have them as a new soft wash customer whether they paint or do not paint.
4) My suggestion is to first clean with Blackwash (5:1 to 10:1 depending on the severity of the colonisation) to produce a fast result, applying it with the Benz 10 nozzle.
Thoroughly rinse down (a power washer with a rinsing nozzle or wide angle fan jet works well. And turn the pressure down if you can do that on your power washer. At the very least keep the nozzle at least 12 inches, preferably more, away from the surface as a high pressure jet will damage the render. The ideal is to have "hose pipe" pressure at the point of contact with the render.
Then spray the render with Benz Biocidal Wash using the 6.5 nozzle. You could use the 10 nozzle but the 6.5 will be more efficient. If your customer baulks at the price of treating with both chemicals, then Blackwash alone could be offered. Personally we think this would be spoiling the ship for a halfpenny worth of tar – but if that's what the customer wants ...
Q: Can Blackwash be used to clean granite?
A: Yes. We've had excellent results with newer stone. Older stone (100 years plus) can be harder to clean but will still come up well.
Our best results have been in achieved by brushing-in Blackwash followed by light pressure washing.
As there are so many different types of granite in different locations is difficult to give a definitive answer. We suggest treating a test patch first to give you and your customer an idea of how the product will work.
Q: Is there any way to avoid having to get up on roofs and physically remove the moss by scraping and brushing?
A: Our suggestion is to employ a roofing contractor to carry out the moss removal. They will have the equipment, experience and insurance. You would simply arrange for this to happen and then treat the roof afterwards.
Q: Slates, apart from natural slates, are made from asbestos fibre cement. What insurance companies cover this risk and soft washing and working at height in general?
A: Modern slates like Tegral are not made from asbestos-containing material. Best not to work with old slates if you can not get insurance and tell the insurance company that you do not work with asbestos.
The best insurance company in the industry at the moment seems to be Hiscox.
Q: How do I remove yellow lichen from Decra roofing tiles.
A: If your customer is prepared to wait for results you could use two treatments of Biocidal Wash at 50:1. Two applications prolongs contact time with the lichen, which will take time to self-cleanse but will go in a few months.
You could also use Blackwash at 5-10:1 (depending on severity of colonisation) to give more instant results.
As always, treat a test patch first as you may find that the coating has degraded/faded under the colonisation of lichen.
You may also find that the panels have faded in the Sun before being covered in algae. So your customer needs to be prepared for the faded surface to be exposed when you clean it. This is similar to what can happen to man-made slates with painted coatings.
Q: How can I prevent leaving runs and spotting on windows?
A: Windows should be rinsed off, leaving only water on the glass. Depending on the mineral content of the water it may leave runs and spotting on the windows when it dries.
Some contractors leave windows like this and let the rain rinse off the tap water. But this is not best practice in our view.
You have several options:
1) Clean the windows yourself using a mop/applicator and squeegee.
2) Invest in water-fed pole window cleaning equipment so you won't need to climb ladders.
3) Arrange for a local window cleaner to come the day after you clean the property.
4) Explain the situation to your customer and get their agreement to arrange to have them cleaned by a local window cleaner.
Q: Do you run any soft washing training events? Your excellent website has more help and advice on it than any I’ve seen before, and I also like to learn hands-on.
A: We are looking at offering regular training events next year. In the meantime:
1) We can set up a demo session and introduction to all equipment and chemicals in Cork, Ireland if you are able to get there. Let us know if you are interested.
We are continually adding to the information, including soft washing how-to videos.
2) Study all the how-to articles and videos listed on the drop-down menu that you will find by clicking on the FAQ top menu item. We created this to serve as the best online soft wash training available in the UK and Ireland.
Click here to subscribe to our YouTube video channel so you receive notification of new how-to vids as we publish them.
3) We are exploring the possibilities of offering UK training courses and will let our "Trade Tips" blog subscribers know as and when these are available. We do not have a time schedule for rolling these out as yet, so Cork is you best short-term bet.
What we’ve done in the past is set up product and equipment demonstrations for a few interested contractors here in Cork, based at the premises of one of our equipment supplier partners. We show the different types of application equipment, go through some health and safety considerations, and do a couple of demonstrations.
Let us know if you are interested and we’ll let you know when we put the next event together.
Q: Are your products recommended by K Rend?
A: K Rend have confirmed that our methods and chemicals are safe to use on their products and will have no detrimental effects at the dilutions we suggest.
Q: What would be the costs for soft washing equipment and chemicals?
A: Here's our suggestions for your next steps:
Click here to visit our dedicated equipment page. We only sell soft wash nozzles, so please contact our recommended suppliers listed at the foot of that page for all equipment quotes.
Q: Have you ever had any issues with Sky dishes rusting? We’ve a customer who thought their dish has rusted from us using Blackwash on their render.
Also, click here to download our free Contractor Pricing Guide – which gives a lot of data on the quantities needed as well as detailed suggestions on how to price new soft wash contracts. (you will be automatically subscribed to our free Trade Tips blog in which we regularly post useful how-to soft washing tips) .
A: No but Sky dishes do rust a lot, especially near the coast. It’s the salt in the air that encourages rusting.
If Blackwash is not thoroughly rinsed from the dish, some salt from it’s decomposition may be left behind, which could speed up the rusting process.
It may be wise to take photos of Sky dishes beforehand, so you have evidence to show that damage had already occurred before you soft washed the property. And remember to rinse those dishes thoroughly.
Q: My customer is looking for a method statement along with SDS sheets for your soft washing products but am concerned that they may try to buy soft washing products direct from Benz Softwash.
A: It is quite common for end customers to request SDS sheets. Very rarely do they then try to buy.
We do not sell our professional quality products to the general public or companies not competent in their application.
Q: How do I treat efflorescence on render?
A: It is important to first check if there is an underlying problem with the render and if so that must be remedied. Then 8% dilute hydrochloric acid can be used to successfully treat the efflorescence.
Q: What's the best and safest way to treat powder coated aluminium with Benz Blackwash?
First, always treat a small, obscure test patch if you are unsure of the effects of treating a surface.
Secondly, all metals benefit from being rinsed before and after applying Blackwash.
Thirdly, be aware that the colour can fade over time and so it's wise to let your customer know that the cleaned surface may not look as it did when new.
Fourthly, dilute Blackwash to 10:1. At this level of dilution it is non-corrosive to metals.