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Common water blasting mistakes

Not all exterior cleaning is created equal. These 4 real-life stories show why experience matters, and how the right fix can save you thousands.
July 4, 2025
Blast Away Guy Pete with his branded shirt touching his goatee and looking like he’s thinking hard about things going wrong

Cheaper doesn’t always mean better!

We’ve seen a lot over the years, from quick fixes gone wrong to well-meaning efforts that didn’t quite deliver. Sometimes it’s not about bad intentions, but about missing the right tools, knowledge, or approach. When it comes to exterior cleaning, small oversights can lead to big problems, and preventable costs.

We know price matters. But shortcuts can cost more in the long run. That’s why we believe in doing things properly the first time. The stories below highlight what can go wrong when care is lacking and how a thoughtful, experienced approach can save time, money, and stress.

Four real stories of what can go wrong.

Whether you choose us, go with someone else, or decide to tackle it yourself, we want you to feel confident about what to expect.  Knowledge is power.

1. The concrete cost-cutting that cost 4 times the $$

We were recently brought in by a third-party building and construction company to quote a pre-paint wash and a concrete wash for their large concrete parking area, driveway and paths. 

They had been using another company, and we had been recommended to them as they were not overly happy with the results.  They were finding that the mould was back on the concrete and parts of the building within a couple of months. And concreate looked worse than before as time went on it showed more and more wash streaks.

This wasn’t just a case of poor cleaning, it was a missed opportunity to protect the surface properly. A simple post-wash treatment could have made all the difference.

On top of that:

🚨 Ugly wash marks were left all over the concrete. At first, there were not many, and they were faint. After a few months, more and more showed up, and they intensified. When treatment is applied, it works for several weeks to continue cleaning the concrete (making it look even better) and ensuring an even finish.
🚨 A $845.50 job needed to be done four times a year to keep it looking good and prevent it from becoming slippery and dangerous.
 

How We Fixed It:

✔️ We took the time to properly treat the concrete, not just wash it, which meant fewer cleans needed, and no patchy wash marks.
✔️ Our finishing treatments helped the concrete stay clean longer, delivering a result the client hadn’t seen in years.
✔️ Instead of four cleans a year, they now just need one. That’s more peace of mind, less hassle and better value.

2. The costly mistake of unnecessary roof washing when a roof treatment would have done the trick

We were asked to quote a building and roof wash for a large commercial property in Whangarei. During our discussions with the building owner, we discovered something surprising:

They had been paying another water blasting company $7,217 yearly to wash their relatively new roof. The problem? It wasn’t necessary.

The thing is, many roofs don’t need high-pressure cleaning at all — and in some cases, that much pressure can actually cause long-term damage. For thousands of our residential and commercial clients, a tailored treatment plan is all that’s ever been needed. No washing. No wear and tear. Just reliable, proven results — some for over 12 years and counting. It protects their roof, their warranty, and their wallet.

When we explained this to the building owner, they were shocked. Instead of selling a service the client didn’t need, we explained the difference. A soft, expert-led approach was better for their roof and their wallet. Importantly, this approach also aligned with the roof’s warranty requirements, ensuring its validity and protection against premature damage.

This isn’t just about saving money. It’s about choosing the right method, at the right time, for the right reasons.

Proven results, massive savings

To reassure the owner, we shared examples of other large commercial buildings in Auckland and Whangārei that we’ve been treating for years, some for over 12 consecutive years. The result? Those roofs were in pristine condition, without the need for excessive pressure washing.

The cost difference?
💰 Annual roof wash from their previous provider: $7,217.00
💰 Annual roof treatment with us: $2362.81

That’s a saving of $4854.19 per year, without compromising the cleanliness or longevity of the roof.

This client is so happy with our recommendation, approach and workmanship that they gave us all their other commercial building wash-down work. 

The takeaway? 

This building owner was spending thousands of dollars simply because no one had explained a different, more cost-effective approach.

If a roof wash is required, we also apply a post-wash roof treatment afterwards to kill all the mould spores and ensure the roof stays clean for longer. The company they had been using was not doing a post-wash treatment.

Sadly, we also encountered a solo mum from One Tree Point who had been led to believe that her roof needed a yearly wash and was paying another company to carry this out.

She heard about us and now gets us in to treat her roof every 3 years at our recommendation, as that is all that is required given its steep pitch.

💡 If you’re paying for regular roof washing, it might be time to rethink your approach and get a quote for a roof treatment to keep your roof clean. A tailored, expert-backed solution could save you thousands while keeping your property looking its best.

3. When the wrong water blasting tools cause damage to your property.

A homeowner in Kensington, Whangārei, recently hired a cheaper water blasting service to wash their character bungalow. 

Unfortunately, the wrong gear and a heavy hand caused real damage. It’s not that the contractor didn’t care, they just didn’t have the right know-how for this kind of home which resulted in:

🚨 Stripped paint on the cladding
🚨 Damaged decking. The timber became feathered and rough
🚨 Frustration because the home owner had to repaint the cladding and put up with feathered decking

The home owner initially requested a quote from us but chose a lower priced option. In the end, they had to repaint the cladding and replace sections of the decking. Work that might have been avoided with a different approach.

When they asked us to return later, we took a more careful approach:

✔️ We skipped the pressure and used a specialist product for the deck, preserving the timber.
✔️ Our soft washing method brought out the beauty of the cladding , no risk, no stress.
✔️ We put together a plan so they could keep things looking great, with no more damage or do-overs.

4. The roof that should never have been washed

This story still sticks with us, not because of what went wrong, but because of how easily it could’ve been avoided. A few years ago we were called to quote a range of soft washing work on a beautiful 1900s character in Mairtown, Whangarei. During our walkthrough with the homeowner, they shared their concerns about potential damage. Not only because of the age of the property but also due to a previous experience with another contractor.

They had hired a company to wash their old iron roof. Instead of carefully assessing its condition and recommending a gentle, cost-effective roof treatment, the contractor went ahead with high-pressure washing.

The result?

🚨 Water leaks due to damage caused to the old, weakened iron panels.
🚨 A big repair bill, the homeowner had to replace sections of the roof and wet insulation.

If the contractor had assessed the roof's condition in more detail, they may have recommend a safer alternative and helped avoid damage and unexpected costs.

How we would have handled it

✔️ Assessed the roof’s condition and advised against washing, preventing damage.
✔️ Recommended and quoted a roof treatment instead—a safer and more effective option that would have cost a fraction of the price of the roof wash.
✔️ Proposed a specialised treatment to neutralise and slow rust development, protecting the roof without pressure.
✔️ We always prioritise long-term solutions over quick fixes, ensuring homeowners get the best value and safest outcome.

When you work with an older home, it’s not just about what you can do, it’s about what you shouldn’t. That kind of thinking saves money, repairs, and stress.

6 ways to spot quality (and avoid the regret)

✅ The right tools, pressure and products are used for each surface. That means no damage just smart, surface-safe care.

✅ Every application is precise, ensuring a thorough clean without harming your home or building materials.

✅ Mould-prone surfaces are treated after cleaning to slow regrowth and extend the results. If there’s no mould, there’s no need and no extra cost.

✅ Gutters are cleared using techniques that protect cavities and prevent internal leaks.

✅ Ladder stabilisers and safety systems are used to prevent dented or damaged gutters.

✅ You’re backed by the 100% Love Clean Guarantee. Not happy? It’s fixed — or you don’t pay.

The bottom line: cheap can cost you more

We totally get that budgets matter. But cutting corners on exterior cleaning can lead to rework, repairs, or worse. With over 12 years of experience, 8,000+ properties cleaned, and a reputation built on care, we help you get it right the first time.

Before you book any service, it’s worth asking:

✔️ What’s included, and what happens if something goes wrong or I am not happy with the result?

✔️ Will the method protect your property, or just get the job done fast?

✔️ How long will it stay clean, and will I need to redo this again in a few months?

Exterior cleaning doesn’t need to be risky. It just needs the right people, using the right process. We’ve seen that great results come from care, knowledge, and a bit of pride in the work. And that’s what we show up with, every time.

👉 Need expert advice? Get in touch for a quote that prioritises quality, safety, and long-term results.

We’re human – and we own it

We believe in doing things right, not rushed. That means careful prep, a smile when we show up, and a little extra care when you’re not expecting it.

We’re not perfect, but when something’s not quite right, we don’t disappear. We fix it. And then some.

Every now and then (and it’s rare), miscommunication or mistakes can happen.

But here’s the difference: when we get it wrong, we don’t just fix it. We make it better than right.

Our passion for happy, wowed clients is what led us to create the 100% Love Clean Guarantee. Love it, or you don’t pay.

✅ Not completely satisfied? Let us know and we’ll be back to make it right.
✅ Still not happy? You won’t pay a cent.

100% love clean guarantee in action (case in point)

We returned to a job after a communication breakdown left the customer unsatisfied. Instead of just “fixing” it, we went all in—rolling up our sleeves to exceed expectations.

Here’s what they had to say:

⭐️⭐️⭐️⭐️⭐️
"I have no trouble recommending this company. I applaud their integrity and the exemplary service they provided to us. If there were a 10 out of 10, they would certainly get it. I was most impressed with their genuine desire to ensure we were happy with the result of their work. This is often overlooked as a component of a large company's motivation and ideals."

M. Fletcher

Remember, we are here for you every step of the way. Questions, concerns, or just a chat about how we can further tailor our service for you – we’re all ears!

Here's to cleaner, happier spaces.

Clean looks good and makes you feel great

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