Which Type of Cladding Leaks the Most?

One of the most common questions I get asked, especially from first time home buyers wanting a building inspection:

“Which type of plaster cladding leaks the most?”

Let me get directly to the answer, based on inspecting over 1300 plaster houses at the time of writing this. It’s not very often that water physically gets through the plaster system when there are no cracks in the cladding.

Here are a few of the reasons why houses leak: (These causes can get worse with no cavity and untreated timber framing)

  • Where the cladding meets the window joinery it’s not flashed correctly causing water to get in behind the plaster, then further down in behind the building paper and onto the framing.
  • There are no head flashings above the window, letting water in around the top of the frame
  • Large cracks in the cladding allow water to soak through in behind cladding and possible through building paper penetrations.
  • Decks leak directly down into the wall and onto the timber framing
  • Internal gutters leak or butanol membranes fail from not lipping high enough up underneath doors/parapets and so on.
  • Water gets through fixings such as deck railings, nails and anything screwed through the cladding etc

There are plenty of other reasons that cause leaky buildings (or isolated leaks), but as you can see above that it’s not the actual plaster itself that leaks… it’s the workmanship and design of the home that is the problem. You could stand there all day with a hose and spray a large section of polystyrene or harditex cladding in an area where there are no windows, and it won’t leak directly through (Providing there aren’t any cracks). Even if there are cracks in areas away from windows, the water still needs to get past the building paper to penetrate the framing. Then… you could spend just 10 minutes spraying the nearest window and it might leak like crazy right away if it’s not sealed/flashed correctly or the window mitres have failed.

Other common opportunities for moisture to enter your walls which could cause you grief:

  • When your shower plumbing (such as the mixer) is up against an external wall. A slow drip in the plumbing will then proceed to fill your external wall framing with water every time the shower is used! It’s get worse if it’s on the top floor because gravity takes over and it fills up the lower level wall below it also. Nice!
  • If you get any condensation then you need to stop it asap. Not only does it cause unhealthy mould on curtains, it runs down the window and potentially rotting the sill (Which has a timber sill plate below it), or even worse the internal mitres on the window have failed and you wall is filling up with condensation water… even on those sunny days.
  • Shower screen leaks. If your shower is leaking water out the corners of the screen, then reseal it asap with a high quality sealant. We have seen many cases where home owners just think “It’s only a shower leak… no big deal“… well… it starts getting into the wall without you knowing and can become a real headache. Have you ever seen the gib board in the corners of your showers start to look like you could put your finger through it? Too late… the water is already in the bottom plate and possibly in behind the shower box itself.

Both home owners and buyers need to take care of the property they own or are buying, because it’s the small leaks that you already know about that turn into big decreases in your bank balance over time. Remember, if you can see visual evidence of moisture problems then it’s already too late in many cases.

Get a thermal imaging quick scan today and stay ontop of any pending disasters before they get out of hand! We give free quotes over the phone for these type of ‘peace of mind’ inspections, and it’s well worth it every time.

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Radio Recording for Thermal Imaging Inspections

We have built a strong & credible name in the NZ house inspection & infrared thermal imaging industry over the years. If fact, Google have placed us as #1 in their rankings for the above topics…  hence why you have landed on the most comprehensive leaky building inspection website in NZ. 

We have uploaded a recent recording of an advertorial we recently did on Newstalk ZB so you can put a ‘voice’ to our name:

Listen Here (Runs for 1.5 minutes)

We have been thermal imaging houses for years, and also offering leak detection services for those home owners who have a leak they can’t find, or are worried they could potentially buy themselves a home with leaking problems.

Call us first… you’ll get the best quote, prompt service, and most importantly – experience. We offer guaranteed free quotes over the phone! (Our quotes don’t change once we turn up to the job).


Even Newstalk ZB’s DIY Home Renovation Expert Peter Wolfkamp Has Used Our Services, and Recommends Us Live Online – Listen Here (Runs for 30 seconds)


Winter Leak Detection House Inspections

Is Winter a Good Time for A Leaky Home Inspection?

It goes without saying… if you are buying a home, it’s MUCH better if it’s been raining. A thermal imaging building inspection will clearly show leaks within a week of heavy rain. It’s only logical to test the house for leaks under the worst possible weather conditions… particulary for roof, deck and window leaks. 

Leak detection services in NZ will vary in results depending on the type of equipment used during the home inspection. It’s important to understand that thermal imaging cameras are excellent for detecting leaks on ceilings, under decks, roofs, back of showers and under windows, whilst moisture meters are the best method for testing for moisture problems in external walls.

What if it hasn’t rained for a few weeks, is it still possible to find moisture in walls?

Yes. In NZ, the typical homes we get hired to test for moisture are plaster systems with no cavity system. If the home has no cavity, then the moisture and condensation gets trapped behind the walls and soaks into the timber framing and insulation. The moisture testing meters we use are highly sensitive and will detect the slightest change in timber and gib board density caused by higher levels of moisture.

What about roof leaks after no rain?

It is true that a roof leak that hasn’t found it’s way into an external wall may go undetected in summer months… but the good news is that a roof leak is generally easy to fix, and it’s the least harmful type of leak that can be found in a home (As long as it hasn’t travelled into an external wall). Generally, if the leak was that severe you would see visual signs of damage or discolouration on the ceiling.

The insulation batts may be wet also… but if you have a pitched roof, you can crawl through the manhole and substitute the wet insulation with new batts. If it’s a mono pitched roof (Can’t crawl inside), then you can either fix the source of the leak and let it dry out, otherwise if it’s showing on the gib board you can open up the ceiling and take out the saturated insulation. Not such a big deal considering there is moisture damage to the ceiling anyway.

In summary, winter is an excellent time for thermal imaging inspections and general leak detection investigations. Summer is normally fine for moisture inspections, unless it hasn’t rained for over 3 weeks or so. Don’t rush your property purchase if you feel the place could be leaking and it hasn’t rained for some time. Give us a call if your aren’t sure if the timing is right for you.

Dux Qest (Ducks Quest) Plumbing Leaking

How do I know if I have Dux Qest plumbing in my home?

Dux Quest plumbing is notorious for leaking, and now the insurance companies are even putting clauses in their fine print that says they won’t cover any burst pipe leaks in houses that are fitted with Dux Quest.

You may need to get a plumber or building inspector in to identify for you if your property is fitted with this product.

If you can crawl under your home, you may be able see the writing on the black pipes… and if so, consider getting it replaced because if it leaks into your external walls, the damage bill could get rather large. You won’t know it’s leaking until it’s too late, as it’s normally a slow leak at one of the joins that gradually eats away at your wall.

One home owner had the ceiling collapse onto their kitchen bench from a leak in the shower above!  If you are buying a house, ask the inspector to look for this plumbing type.

Moisture Detection Companies and Services NZ

With the leaky building crisis in full swing, and the building industry slowing down again, there is now a glut of new building inspection and moisture detection companies entering the market.

How do you know who the ‘newly registered’ home inspection companies are in the past year or so? Simple. Just go to the companies office website and do a search for their company name… that’s the fast and most accurate way to REALLY tell how long they’ve been in the business for!

We pride ourselves on being one of the longer standing moisture detection companies in Auckland, Wellington and Christchurch (operating NZ Wide) with some of NZ’s most high profile companies on our books, including several councils and publically listed companies who use our services time and time again.

What’s happened recently in the NZ building inspection services industry, is builders started to run out of physical building work, and as a result they suddenly turned into inspectors.

What happens next? They start inspecting homes with a potential ‘hidden’ agender. We called up 1o companies who have started inspecting houses in the past 2 years and asked them if they fixed any problems they found. 8 out of the 10 house inspection companies surveyed said “YES”, or they could refer someone who could. 5 of them did not carry a thermal imaging camera.

So now… is it really an independant inspection if they also sell repair services also? Possibly not. This goes for pre sale, pre purchase moisture detection and building inspection services.

The way we’ve built our company over the years, is by sticking to a policy of non-biased inspections, which means it makes absolutely no difference to us if we find zero leaks, or 10 leaks using our leak detection equipment and techniques. In addition, we do these moisture inspections with reports at the best possible price possible, based on the area where you live.

Buying at Auction Costs & Tips

Are you buying at action?

Sadly, many people get ‘caught out’ at auctions in NZ because they don’t know what to look out for.

It’s almost sickening how many properties we end up moisture testing in NZ for clients who ‘just purchased’ at an auction, only to move into the house and find signs of leaks (most of which were hidden under carpet and behind furniture etc). Most of them ‘thought’ the house looked fine from what they could see… before they purchased the house. In addtion, they thought they got a good deal!! I wonder why?

Basic buying at auction costs and tips:

Is getting a thermal imaging leak inspection a cost, and money I could potentially loose before an auction ? Yes it is… but don’t miss this step! It’s AMAZING how many times clients say to me “We didn’t want to pay for an inspection incase we didn’t win the auction”. Just plain silly thinking don’t you think? Absolutely.

99% of my clients have it written into their property contract to get a building inspection and/or moisture test prior to buying the house, so why wouldn’t you do the same in an auction scenario?

What should you look for prior to buying at auction? (From a leak detective’s point of view)

  • Look for swollen skirting boards
  • Look for discoloured carpet grip in the corners under the carpet. This will most likely mean a leak is coming in from somewhere
  • Look for any visual signs of joinery failures
  • Look for any bubbling of paintwork under windows, on ceiling, in bathrooms and on just about every surface of internal and  external walls
  • Cracks in cladding and around windows
  • Lack of ground clearence
  • Any leaks around plumbing, such as under sinks and in the corners of shower screens.

These tips listed above are only a hand full of what to look for in your initial ‘visual’ inspection. The next step is to get an experienced thermal imaging company to take a look using infrared technology to detect issues you will not see, like these ones… coupled with experience in moisture testing nz houses.

Do not buy at auction until you are 110% sure there are no moisture issues in the house… and we say this with certainty after seeing so many home buyers getting caught out buying lemons. If anything, we can do a verbal inspection for you (no report), which is cheaper and will give you certainty when you buy. If you are happy with the inspection results and win the auction, you can then request a report for a small fee.

Internal Gutter Leaking

Infrared Thermal Imaging Clearly Identifies Leaking Internal Gutter

Insufficient butanol join overlap causes major headache for home owner!

One of the very common signs that you could have a leak or moisture in your ceiling space (normally flat roofs), is you can see signs of the gib board pulling back down over the screws that are holding it up. Have you seen small round marks on your ceiling the size of a screw head? That could be more than meets the eye.

One of the inspections we did this week detected the exact problem as outlined above, although the home owner had no idea what was ACTUALLY going on. They called us in because they had a damp smell in the room and couldn’t work out where is was coming from.

Here’s what we saw with the infrared leak detection camera the moment we walked in the room…

Those big black round marks are leaks detected as seen through the thermal imaging camera on the ceiling of the ‘damp smelling’ room… and the home owner has absolutely no idea these leaks even existed.

The home owners issue was solved within minutes… but finding the source of the leak in the butanol lined internal gutter was the next challenge. Well actually it wasn’t a challenge at all. Instead of using the standard 100mm overlap at the join of the butanol, the 45 angle in the corner of the internal guttering has caused the issue by flapping up slightly thanks to a shortfall in overlap on the join… not to mention that water that was pooling the area!

On the ceiling you could clearly see the gib fixing screw heads where the water had basically saturated the gib above and under the weight (and gravity) caused by high levels of moisture caused a slight sagging in the ceiling.  What to do next?

Step one is always to fix the source of the leak first. Then it’s probably best to cut the area open and pull out the wet insulation, otherwise all that trapped moisture could cause the ceiling to eventually sag right down and make a mess! It’s always good to have a visual inspection of the area in a situation where a roof has been leaking for some time, as mould growth could be taking place.

Here’s another photo of a leak at the top of a wall thanks to leaking internal guttering. The thermal image is over the top of the visual image how we see it during an inspection…

If you have any ‘visual’ cues that something isn’t right with your home, or an unusual damp smell has suddenly appeared that wasn’t there this time last year, then jump straight onto it and get a moisture ‘check up’ on the house.

Finding Balcony Leaks and Preventing Structural Failures

Leaking balconies can be a serious danger, especially if its been leaking slowing for some time before you notice it.

There are plenty of ‘real’ stories about balconies collapsing under load (too many people standing on it at one time), but the most common cause of balcony issues isn’t the load, it’s the fact that the waterproofing has failed and the joists are suffering gradual leak damage and rot which is causing the failure.

You can see in the above photo the discoloured timber cantilevered joists have completely rotted. So do you think decay and rot may have also spread down the external walls below… like cancer? There is a very high chance this has happened, especially with untreated timber behind the plaster cladding.

If you notice any discolouration on the interior lining at the top of your walls or on the ceiling of the room below a balcony, there’s a good chance it’s a leak. Here’s the challenge to finding balcony leaks…

  • Is the water running back across the joists under the deck from outside edge?
  • Has the tile grouting perished and the water is leaking through a join in the waterproofing membrane under the tiles?
  • Has the joinery of the door leading out to the deck failed?
  • Is the base of the cladding touching the deck? Water can potentially ‘wick’ back up into the bottom plate of the timber wall frame.
  • Has the waterproofing membrane been correctly installed underneath the door frame to prevent wind driven rain getting up underneath the door and down into the wall below?
  • Is the water coming down from the roof and running down the external walls?
  • Any cracks in the plaster cladding around the balcony or external walls in the area?
  • What about where the balustrade butts up against the cladding… is the area sealed correctly?
  • Is the deck level the same as the floor level inside the house, or is there a step down of around approx 100mm onto the deck? (The latter is the correct way to build under the current building code).
  • Is the leak visible on the under side of the balcony?
  • Is the balcony drain blocked, or some kind of plumbing failure occured in the area?

Our thermal imaging and moisture detection services can go along way towards detecting balcony leaks through a process of elimination… and might save you from accumulating a few grey hairs in the process!

The one thing you need to make sure of, is that you don’t leave the leak go ‘unsolved’, because the longer you leave it, the higher probability the moisture is eating into your external load bearing walls. Not good.

We find balcony leaks and determine if moisture has penetrated your walls.

Thermal Imaging Used to Detect Bracings and Fixings Behind Walls

Are you considering renovating your home, or trying to get a CCC and need a simple way to prove the appropriate bracings, studs and nogs are in place?

Using our infrared cameras is the quick way!

As you can see in the thermal imaging photo below, there has been alterations to this wall which the home owner didn’t know about. More importantly, you can see the builder has installed diagonal bracings behind the wall to strengthen the area.

There are very few techniques available that will give you such a clear picture of how your walls are constructed, without having to do damage. We have thermal imaged quite a few ‘granny flats’ and add-ons that were built without a CCC … and with our unique thermal imaging reports, we’ve helped strength our clients cases to get buildings passed through council without removing any sections of wall.

Just like a female goes to get breast thermography for pain free screening, or a dentist uses an x-ray machine to see what’s happening behind your gums before he/she operates… thermal imaging of NZ houses is the best possible way to detect leaking problems, building construction, moisture detection and missing insulation detection.

Get the visual facts about your house before making any structural or renovation decisions (or painting the house).