Different Types Of Building Inspections 

Pre-purchase Building Inspection

There are a number of Pre-purchase type building or home inspections that you should consider when purchasing a home. The main three are; Maintenance Building Inspection, Infrared Moisture Inspection (sometimes also called a Thermal Imaging Inspection), Valuation Inspection. All these inspections are often generally referred to as a Building Inspection. Other types of inspections can be required to, particularly if there are any concerns due to the age of the building or from the results of a building inspection report. These can often require further building inspections from a qualified Plumber, Electrician, Structural Engineer, Builder or Registered Building Surveyor.

Building Inspection, originally called a Structural Inspection or more commonly now called (Maintenance Inspection), as most inspectors are not suitably qualified to comment on structural issues. Sometimes these inspections include moisture testing but normally on a limited level only and would not be considered a full moisture test. Detect-A-Leak does not conduct Structural Inspections our inspections are all about moisture and moisture related issues, but often a lot of moisture issues are maintenance related and therefore moisture related maintenance issues will be checked and included in our reports.

Building Moisture Inspection - Thermal Imaging Inspection - Infrared Moisture Inspection:

As moisture and related issues are such a big concern and problem in New Zealand this type of inspection is very important, particularly if the home in question is built prior to 2005. We would recommend our inspection is completed prior to any other inspection as we often find significant moisture issues that can make completing the sale undesirable. All homes even brand new can leak if not correctly detailed and yes we are still building leaky buildings. Detect-A-Leak reports are comprehensive having both digital and thermal images along with a number of photos of the moisture levels taken at the time of the inspection. With our Pre-purchase Infrared Moisture Inspections we also inspect the exterior envelope for moisture concerns, moisture related issues and take digital photos of moisture readings taken on the interior walls for the report. IR photos can be taken of selected exterior locations if required or a IR Cladding Inspection can be added if you want additional exterior IR images. Having an IR camera as a tool to help find moisture issues is a big advantage over just using a moisture meter as the thermal images can make the moisture visible. Moisture meters only give readings on the small spot it is contacting. We sometimes have to view the anomaly through the IR camera to get the moisture meter reading at the right location. Anyone that tells you that there is no advantage in using an Infrared Camera to find moisture or that it doesn't work (as some companies advise) have not seen the results of our inspections, probably don't know or understand the technology or simply can't afford to buy an Infrared Camera.

Cladding Thermal Imaging Moisture Inspection

Using Infrared (IR) Cameras for Cladding Inspections is a great way to find where the problem areas are as they can be seen within the Thermal Image or to give additional visible evidence to a suspected moisture issue. The framing and even nail fixings and often visible in the IR images. At Detect-A-Leak we prefer to conduct a full cladding inspection with our moisture inspection in order to get a more informed picture of what the images are showing. Although we inspect the cladding as part of our normal moisture inspection and take a number of digital photos we don't normally take thermal images of the exterior unless a problem is detected during our inside testing, due to the added time and cost involved with taking exterior thermal images. However for inspections for the banks or when requested we are happy to take the additional exterior IR photos. This adds about 30mins to 1 hour extra to our time on site. The IR images are great for showing moisture in the cladding but it needs to be remembered when viewing the IR images that this does not necessarily mean the moisture is getting past the building paper and into the home. The additional exterior images taken are added to the report and often mirror an anomaly image taken on the inside when there is confirmed moisture. We are happy to discuss our reasoning for this. See more about the different types of cladding.

Health Check Infrared Moisture Detection

Have you wondered or are you worried that your home could be leaking? Then a Health Check Moisture Inspection is for you. We will conduct a full Moisture Inspection of the home. We will inspect the exterior envelope for moisture concerns, moisture related issues and take digital photos for the report. IR photos can be taken of selected exterior locations if required. Then we will conduct a full internal moisture test taking both infrared and digital photos for the report. This can be a bit like going to the dentist where it gets put off for fear of the outcome, but as we know if you need a filling and you do nothing about it the problem just gets bigger. The same applies with moisture issues; they will generally only get worse over time. So the sooner the issue is sorted the less it should cost and the better you will sleep at night. The great thing about the technology we use is early detection. Most of the issues we find that are not visible often haven't caused much damage because they are detected at an earlier stage, not unlike a dentist taking an x-ray can detect a filling before you do.

Pre-sale Building Inspection

A Pre-sale Infrared Moisture Inspection is often conducted on homes built prior to 2005 to help the vendor and aid the real estate agent to sell a home that may otherwise be difficult to sell because of moisture concerns. Due to age and types of building materials or practices used at the time the a home was built a lot of homes are considered high risk of having moisture problems or leaky building syndrome. Buyers are now much more informed about leaky building issues, sometimes moisture reports are required for the bank (see bank inspections below) and therefore want them moisture tested. When we conduct a pre-sale inspection we concentrate on moisture testing the exterior facing interior walls from within the home and around wet areas such as bathrooms and kitchens. The reports are comprehensive having both digital and thermal images along with photos of the moisture levels at the time of the inspection, giving the prospective buyer the confidence that the home has been properly moisture tested.

Weathertightness Survey

A Weathertightness Inspection is often generalised as a Moisture Inspection. There are specific courses to become a Certified or Registered Weathertightness Surveyor, most are heavily focused on invasive testing, compliance with the building code, weathertight claims and remediation work and can be quite costly. If you are wishing to register a leaky home and make a weathertight claim and you home is less than 10 years old then you need to use a Certified Weathertightness Surveyor. This type of testing can be quite involved, expensive and not that practical for Pre-purchase or general Moisture Inspection. Invasive testing may include: drilling holes in walls, cutting holes in the external cladding and taking timber samples for laboratory testing. Most weathertight surveyors don't use thermal imaging and non-invasive testing is generally a smaller part of there business.

Our method of moisture testing concentrates on non-invasive testing only and is less involved by comparison, therefore less expensive. Detect-A-Leak is often recommended by Weathertightness Surveyors for an initial Moisture Inspection and we often recommend them if invasive testing needs to be conducted or for larger remediation work or leaky building claims are involved.

Invasive Moisture Testing

Has someone suggested you need Invasive Moisture Testing? Invasive testing of your home could be major or minor depending on the property and the type of report required. Testing may include:drilling small holes in walls (inside or outside) cutting holes in the external cladding (up to A4 in size) taking timber or mould samples for laboratory testing. They will make temporary repairs which should prevent water entry for up to 6 months, but you are responsible for making the final repairs which further add to the costs. 

My recommendation is to start with a non-invasive test. Non Invasive Moisture Testing using Thermal Imaging when conducted properly can be a very accurate way to moisture test a building without cutting holes. Thermal imaging can detect where the issues are likely to be and non invasive moisture meters can be quite accurate at confirming if it is moisture or not. Once areas have been confirmed as damp or wet the problem areas and other suspect areas can be targeted directly. Although the methodology can't be expected to find every issue and areas that have been previously repaired and dried out may not be detectable we believe this is the most thorough way to test a home non-invasively. Often a number of areas that were thought to be okay or repaired are found to have ongoing moisture issues or have been poorly repaired. 

Bank Requested Moisture Inspection

Banks are now requiring Infrared Moisture Inspections or Weathertight Inspections prior to approving or renewing existing mortgages. Generally when a weathertight or weathertightness assessment is requested by a bank a non invasive infrared moisture inspection is also acceptable. The moisture inspection reports with the addition of the Infrared images are considered by many as the preferred option. Often after the bank has seen Infrared or Thermal Imaging Inspection Reports they will start requesting them. I would be happy to clarify this directly with your bank if need be, as I have given a number of educational talks to bank staff and regularly send them reports. Detect-A-Leak moisture requested reports have been accepted by every bank they have been presented to. If the bank has requested the report we need to also do a full cladding inspection for them.

Pre Auction Inspection

Are you looking for a home that is going to auction and don't want the extra expense of paying for a building report on top of the inspection cost? We can offer three options for you.

Option one: We will do our normal inspection and give the information verbally but not document or take photos. This can half the time onsite and greatly reduce the cost. This is a cost driven inspection but as in today's market there are so many buyers at auction you won't always get the home you've spent money on doing pre auction inspections resulting in some customers needing to get more than one home moisture tested. There is a risk that you won't remember all the info and there is a lot of additional information that you will be missing out on if you don't get the report. The disadvantage with this inspection is if you decide later you want the report the inspection would need to be done again.

Option two: We will do our normal inspection, give the information verbally but also document and take photos so that the report can be done at a later date if you are successful at action or want the report to help negotiate a better buying price. There is a risk that you won't remember all the info and there is a lot of additional information that you will be missing out on if you don't get the report.

Option three: We will do our normal inspection, document and take photos so that the report can be written up prior to auction so that you are fully informed and prepared for the auction. This is the more expensive option but it should be remembered a lot of homes that have moisture issues are being sold through auctions and buyers are getting caught buying homes that are leaking.

Targeted Leak Investigation

Do you have a leak and can't work out where it's coming from or have a strange smell or feeling of cold or dampness and don't know whats causing it? If you don't want the whole building tested then a Target Moisture Inspection is what you want. We can come out and use our infrared camera, moisture testing equipment and knowledge to help solve your moisture issue. These inspections are charged on an hourly rate with a minimum 1 hour charge. Are you tired or ringing a tradesman not being able to explain what needs fixing and then not having them turn up? This is often because they know they could spend a considerable amount of unpaid time looking for the source of the problem, which could turn out to be unrelated to there trade. If this inspection is what you need then call or email John 0800 338-328

Post Repair IR Audits

Before timber fascia leak
After new metal flashing
Before sealant flashing leak
After new plastic flashing


It is essential that once repairs are completed that they have been successful and the area is now back to acceptable moisture levels. Once repairs are completed we can come back and re-check the repaired areas to ensure there are no ongoing issues. Sometimes as with water leaks it may be necessary to do a quick moisture test during the repair process while wall linings are off in order to ensure areas are dry enough for work to continue.


Types of infrared building inpections video