Find And Fix Leaks Fast

In Your Plaster Clad Home

Patented and Proven Moisture Detection Probes

RotStop - Turns Untreated Timber Into Treated Timber



Retirement Villages

Commercial Buildings

With No Disruption And No Damage

Building Inspections      Timber Condition Testing      Moisture Monitoring

Treatment Test

Moisture Test

Condition Report and Solutions

Decay Analysis

Making Informed Decisions With Accurate Information Saves Money

RotStop Undertreated Timber to Kill and Prevent Rot in Your Home

Image of rotting timber inside a leaky building

Untreated Wet Timber

Treated Timber

Treat Timber with RotStop

Non-disruptive, low cost, post treatment - without removing any cladding

Inspect Details to Find the Source of any Leaks

Moisture Check tests
the current weather tightness

Test framing condition
in case damage has started behind the walls

“What You Absolutely Must Know About Owning A Plaster Clad House”

Our latest report gives you the answers and the best solutions for understanding the problem and looking after your biggest asset.


  • How the leaky building scandal happened and who is to blame
  • Why houses from 1992 – 2003 are at high risk of leaks and rot
  • How to identify whether your house is at risk
  • How you can find the leaks before they damage your house
  • How to turn untreated rot loving timber into treated, rot-resistant timber
  • How to BUY a plaster clad house without getting a lemon
  • How to SELL your plaster clad home for the best price
  • How to avoid having to re-clad your house or sell it for a song

This research has been conducted by New Zealand’s leading expert in the field of moisture detection and repair and provides real hope for owners of plaster clad homes.

Restore trust and value to your monolithic cladding with accurate moisture detection and treatment

For twenty years, Moisture Detection Company has been restoring peace of mind to the owners of plaster clad houses.

We are the only company who can really find the leaks in your house
(without pulling your house apart)

That’s a bold statement isn’t it, but how can we say that?

Because we invented and patented the Mdu Moisture Detection Probes which are installed anywhere in your house where leaks might show up.  No-one else has this technology.

Depending on how big and complex your house is, we might place as few as 30, or as many as 100 tiny probes under windows, beside doors, beneath deck connections ….. anywhere that our experience tells us that leaks could show up.

Then, every six months we can measure the moisture of the timber inside the wall and tell you whether there are any problems.

But that’s not all. At the time we install probes, we take samples of your timber at every location and test it for decay.

And that’s still not all.  We test a selection of the samples to find out exactly what timber treatment, if any, was used on your house.

And finally, at every probe location, we test the strength of the timber to see if it is still structurally strong.

This give us real, EVIDENCE of how your house is performing and what it needs to keep it safe.

Moisture Detection Probe

Accurate Evidence Guides Good Decisions

So what happens now that we have so much real evidence about:

  • the moisture content at dozens of potential leak points around your house
  • whether there is any decay in the timber and how bad it is
  • whether your house was built with treated timber or not
  • how strong the timber is

What you now have is real information that guides you to make good decisions about maintaining your house and spending your money wisely.

Based on twenty years of experience, we now explain to you what the evidence is saying and what that means for you, your family and your house.

  • If it has a leak or two, that doesn’t make your home a leaky building.  Virtually all houses leak but some are built to stand up to a few leaks. We can find the leaks and fix them.
  • If the timber is well treated then that is a huge positive, but if it isn’t treated, no problem because we can treat it from outside with RotStop.
  • If the timber has some decay then it can often be treated and just left because RotStop kills decay fungus and puts the rot on hold.

Usually, there are a couple of areas that require attention but now we know where they are, we can get them sorted  out quickly.

Sometimes the damage is greater but with the evidence we have gathered we can talk about your options and the best way forward for you.

The risk of not finding out where your house may be leaking can be heartbreaking and expensive.

Real Solutions for Leaky Homes

Are you concerned that your house may have some problems but you just don’t know how to find out or who you can trust?

Moisture Detection Probes have been gathering accurate information about exactly what is happening in NZ houses for over 15 years.  Only when you are armed with the right information, can you make the best choices.

To find out more, visit our “Real Solutions for Leaky Homes” webpage here.

Building Condition and Moisture Monitoring in one tool

Our technicians use the Mdu Probe System to test buildings – repeatable reliable moisture readings today and any time in the future – means your next building inspection report is even more accurate and inexpensive – and assesses timber damage without the need to cut holes through the internal wall linings or damage the exterior cladding.

The more Mdu Probes installed and the more often they are read for moisture (monitoring) the better the facts before the big decisions are made (if they need making). It’s easy for some building inspectors to dictate all the cladding must be removed to find out the framing condition and moisture contents behind the GIB (it’s not their money). Will they say the same next time you need an inspection (even if its been fixed) in a few years when you go to sell? Take the guess work out and install the Mdu Probe permanent monitoring system and regain control of your destiny. We don’t mind if you use us as a second opinion – you’ll soon see why we use the most reliable and accurate building inspection system.

Knowledge is essential

No plan will work if your plan is based on flawed logic? How will you understand you have been given false information? Or worse still accept on face value your home needs a reclad by default? Build a plan around tests performed using our Mdu Probe inspection process. If it needs a reclad our tests will show this to be true. But what if it doesn’t? Our reports are easily understandable, our advice and solutions are practical – together with ongoing monitoring this all adds up to a process that is palatable.

No unsightly damage to your home

Our technicians undertake a visual inspection to identify what parts of the building could be letting water in. These are the risk points. Perhaps that’s all you need right now. That’s okay.

Testing the framing condition below these risk points is what determines it as a leaky building or a building with leaks. Leaky buildings are those where the framing stays wet long enough to rot the framing to an extent the framing (or areas of framing) must be repalaced. Often that means taking the cladding off to gain access. Therefore our focus is on testing the framing below these details (gravity pulls water down) with the Mdu Probe System before these decisions are made – it just makes sense to get the facts first:

  • A very small hole is drilled through the skirting board and into the bottom section of timber framing inside the wall.
  • The timber is tested and samples are collected for analysis.
  • Selected timber samples are tested for treatment type and levels.
  • An Mdu PROBE is inserted into the hole and the moisture contents taken.
  • Ongoing moisture readings can be taken at regular intervals (Monitoring using the Mdu Probe Reading Service) as part of standard maintenance to test moisture levels during winter, summer and after repairs to ensure your building stays okay.

Probes Don’t Lie

Really a matter of preference – ‘Mdu Probes’ versus ‘Cut Outs’ – you choose? Both test Moisture Contents, Fungal Decay and Timber Treatment. Note scanners and heat (thermal image) machines do not provide this information. Often people talk ‘leaky buildings’ the moment they hear the building has plaster. It is very disappointing when even senior building inspectors make these statements without bothering to have these simple tests done – some even believe they have the right to carve up your cladding justifying preconceived positions. We are proving over and over it’s best to wait until the test results are in. Maybe you can save hundreds of thousands like many of our clients.

Probe under window:

  • No damage to cladding. Neat and tidy.
  • Multiple locations can be tested and still no damage.
  • Success of any repairs can be verified by subsequent monitoring.

Cut Out under window:

Needs a reclad now
Fact is these building inspectors destroyed most of the cladding around most windows this way – so now the whole building needs a reclad?
Cut outs are point in time assessments – they provide no way to verify the repair worked – even the reclad next year or the year after that.

Cut outs of a house

Neither Lie – which would you prefer?

  • Taking a moisture reading from an Mdu Probe. Monitoring.
  • Take back control of your home.
  • Gain peace of mind.
  • Excellent proof for pre-purchase reports.

Creating a drier, warmer, healthier home for your family – and protecting its future value

As a homeowner you’ll want to ensure that your biggest asset remains dry, healthy and weathertight.

If you’re building a new home, you’ll use the Mdu Probes to monitor the home whilst its still under warranty. If its leaking it will be cold and damp and getting damaged. It may even be harbouring toxic moulds. It should have been built right. The probes will tell.

If you’re worried our technicians will check its health. It may need some repairs. The sooner you find out the cheaper the repair and the quicker the recovery.

You may have had repairs done recently. You spent good money. Why not make sure and get tests done. That way you can be sure your home is healthy and dry. Order the ‘Healthy Home Check’

You’ve just purchased what you believe to be a healthy dry home. Why not get it checked out so it stays that way and the promises made to you were true?

What’s the point of monitoring?

All homes need maintenance. But how do you know what to do. Painting every 5 or 10 years doesn’t fix defective construction, faulty windows, defective guttering, leaky membranes, incorrect flashings and elevated ground lines. Every bit of decay starts with excess moisture. Moisture that could have been turned off if you knew the house had leaks.

This is the crux of all leaky building claims. Owners were not provided with the tools (moisture probes) to allow effective testing of construction or maintenance. Every car has a temperature gauge. Would you buy a car without one? Then why buy a house without moisture gauges (Probes)?

Without moisture probes you have no idea what is going on beneath the walls hidden out of view. Why should you blindly accept written warranties that builders and manufacturers know you cannot test or have verified without moisture probes? You are entitled to exercise your consumer rights?

In any event its your asset so you can look after it however you want. Perhaps you’ll never need to sell it so it doesn’t matter what condition it ends up in. Perhaps your view is you want your asset to appreciate in value and not cost the world to maintain. Monitoring will help you here. Monitoring tests the effectiveness of construction and maintenance plans. Monitoring and knowing moisture contents is the cornerstone of good building inspection reports.

Think of monitoring as the security system for your house’s structure. The Mdu Probe System can be installed in any home, and is a simple and no-fuss process.

Start today and create a history of good monitoring results so you can get set and ‘ready to sell’

Create a Mdu PROBE System that’s right for you

One size fits all? Not with the Mdu Pprobe System. Every home is different and requires a unique solution. Our rates are competitive.

Perhaps you want to start slowly or in one specific area you are concerned about. That’s fine with us.

Maybe you just want a risk report or some treatment tests done.

We provide free Mdu Probe installation quotes. Some options include:

  • Healthy Home check – limited to 40 Mdu Probes and includes at least 6 treatment tests and one set of moisture readings
  • Full house installation – POA – includes technician risk review and Mdu Probes installed around the building in ‘standard’ locations
  • Testing of selected walls or areas for the purposes of testing treatment, wood condition and moisture contents.
  • Further testing to determine the extent of decay and produce rot maps
  • Site inspections to determine scopes of repairs
  • Maintenance plans and ongoing reading service to monitor home.

Building a new home? Specify the Mdu Probe System on the plans as your independent audit system to keep you in charge and ensure your building warranties are honoured.

Why you should install the Mdu PROBE System.

  • Provides factual information on the state and condition of your home – is the timber treated, does it have decay and what are the moisture contents
  • Provides undeniable proof of your home’s weathertightness every time the moisture probes are monitored
  • Permanent Probes to enable ongoing building diagnostics
  • Early detection system to pinpoint defects before damage occurs – enabling you or your maintenance person to respond and make suitable repairs (under your maintenance plan)
  • Permanent moisture Probes test the effectiveness of maintenance plans. These are the gauges homes have been missing.
  • Assurance to banks, insurers, council, inspectors, repairers and prospective buyers that value can be measured and certain.

All this to combat stigma and give you peace of mind. The outcome of this is your home will be a warmer, healthier and safer home with good saleable market value.

And – no destroying claddings in the process. No worry about how to fix cut outs and drill holes through your cladding. How would these be warranted anyway? Its sad when we see some houses with 20-30 cut outs and hundreds of drill holes – the cladding’s stuffed now anyway. What if our more detailed testing showed 95% of the cladding is good? No need to reclad the back door if the problem is just at the front door?

Got the Probes in – now what?

Test results arm you with the evidence to act (if you want to)

Remember its not illegal to have leaks or decay – unless it is or will cause a threat to occupiers health or safety. A bit of mould here and there are indicators but not necessarily directions to move out. Mostly moulds can be cleaned up – and providing the source of the problem fixed they go away. A bit of decay is not really serious unless it is to a cantilever deck joist or the backbone of the wall bracing system which means the structural integrity is compromised. Leaks can come and go so unless they are causing damage they can be tolerated. Boils down to this – if we tested buildings straight after cyclone Bola all buildings would be condemned. If we tested in April this year after 4 months of paradise weather all buildings would be fine. So who is right? This is why we need to test treatment levels, timber condition and moisture together and on an ongoing basis so we don’t over react – under the weathertightness risk locations. Otherwise its all down to the opinion of the building inspector.

This is what owners do

  • Sell

    Can’t be bothered getting involved – too busy at work or simply too afraid to take on the challenge. Maybe they have been sold a so bad news storey they have given up. When the Mdu Probe system is installed its easy to show the positives so they can move on and sell at fair value – or realise its not all gloom and doom – hopefully before they sell for land value. For every seller there is a buyer who will do one of the options below.

  • Reclad

    A small proportion are fortunate that a reclad cost can be justified by a higher market valuation. Remember a reclad normally involves a new roof, often new double glazed windows, lowered ground lines (or concrete plinths) and a cavity with reduced complexity under the new cladding so its like (sort of) getting a new house except . . . some old framing, untreated framed roof trusses, untreated framed internal walls and untreated floors under upper level showers and bathrooms. Don’t ever expect a reclad to solve everything – the new detailing still needs monitoring

  • Target repairs

    This is small target type work like removing a bit of rot here and there and changing a flashing or two around the building. Maybe some windows get taken out and re-installed with decent flashings. Target repairs have been given a bad name by builders who sold them without monitoring – so the solutions didn’t quite work – it carried on leaking and now needs a second fix or worse still a full reclad. If only they had monitored they would have known whether they fixed it properly. If you have treated timber and moderate weathertightness risk this is a good option.

  • Maintenance

    This is normal work like painting, sealing and undertaking a few modifications to some of the details of a minor nature. This is what we are all used to. If you have treated timber this is a good option. In most cases maintenance will correct most of the problems. That will sort out what the next steps are – it may be your building can survive with a little rot as long as the bad leaks are repaired.

  • Do nothing

    If its already land value and you don’t have the desire or money then it can’t get much worse – we were told every home needs a reclad – in 2003 – yet 10 years on and only a small number have been reclad. The rest are not on the ground as expected – so what’s happening? Many homes will have damage but maybe not to an extent they have become so broken they fall over – or maybe they need testing to prove less is wrong than suspected by others. It is estimated only around 1200 homes have been reclad to date out of possibly 80,000 (Govt sources). Maybe owners are waiting it out – for new solutions to come along – like RotStop and Drying skirts as they don’t trust what they hear.

We help you along the way with whatever direction you chose. Lets keep an open mind.

I now need help fixing the problems – can you find me a contractor – YES

Whether is a full reclad, target repair, some maintenance, a building report or just a chat. We have the skilled people ready to help.

The benefit of engaging us or applying our philosophy is that you become informed so you can see decisions are transparent and not disguised to mislead you.

I bought a leaker – now what?

You meant to! Well done. Did you know about 80% of the time its not as bad as feared. Best advice is get it Probed first and then you’re prepared to make the decisions. You probably deducted the reclad cost so have some room to move. Most intentional buyers of leakers bought because its a good way to enter the market at low prices and mostly they don’t end up recladding. You got a bargain so make good use of the savings. Probes are a cheap way to work out what is actually happening behind the walls. Then decide. Don’t ever believe one shoe fits all.

You didn’t mean to! Not so well done. This mostly happens because buyers relied on poor pre-purchase reports – scanners and thermal image reports are where we see the sorriest stories. How do you know the claims they make are untrue? The industry is not policed so anyone can say what they like. First up get the house Probed. That way you know factually whether you made a mistake or not and whether advice you relied upon was bad and misleading. You may have a claim – its up to you what you to do with what money is left. If its not so bad then maybe its better to fix it up enough so it doesn’t get worse – and spend the legal costs on repairs – at least it can be lived in or rented whilst its a house. If you spend wisely you could wait out the market and eventually come out on top – provided the house doesn’t become terminal in the meantime – so Probe, fix and monitor in little steps and keep the building useful.

I want to get my house ready to sell – but others will think its a leaker

That’s plaster for you! Either get it reclad or get the facts by Probing and show buyers there’s nothing wrong with it – or maybe just a little wrong. The decision you will be faced is a money value proposition only. You have already decided to sell so don’t get emotional about it – get the facts – its your duty to yourself and your family what is the best way out with the best impact on the bank.

$300,000 to reclad or spend $2,000 to Probe and test. What if there was nothing wrong and a buyer was happy to buy on the fundamentals of a dry home. Think bank account?

Do you know buyers think all plaster homes should be land value. Its a free market so if they can get away with that – good on them.

One of our Probe clients was told exactly that – its got plaster so you’ll need to drop $200,000. Our Probes agreed its a plaster home but disagreed with the discount. Our Probes gave nothing but the green light (green is good – low moisture). No rot. It was a treasure of a home. Got $80,000 above CV – a whopping $200,000 more than the Real Estate market appraisal. Can’t guarantee you’ll be as lucky as this couple but you never know until you try.

At the worst the Probes will confirm it needs a reclad – and importantly the Probe results will define the likely frame replacement. This defines costs which means contractors won’t be endeared to include terms like “plus timber removal” which is the start of the road to variations and costs exceeding quotes.

What buyers want to see is our maintenance plans and moisture reports so they can see what is going on and what is likely to happen in the future to base offers on. We see most sellers doing the basic maintenance before selling and identifying larger items with prices so buyers know what they are getting. That is disclosure working as intended. Its not our job to justify a price or offer. Its our job to present the facts of the house.

And by the way – its not just plaster homes. Brick and weatherboard homes are out in the rain as well – and built with the same roofs, windows and ground lines – so leak as well. Did you know that some guttering systems like Taylor Fascia and Klass cause leaks even when the house has wide soffits. Wet ground doesn’t really care which cladding it is up against – it wets them all. Windows don’t discriminate either way – if they are faulty they all leak when it rains.

Contact Us Today

Telephone: 09-2710522
PO Box: PO Box 258056 Botany Manukau 2163
Address: 14 Ormiston Road, East Tamaki, Manukau, Auckland, New Zealand 2016

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