What Type of Timber is My House Built With?

Do you know what type of timber is behind your walls?

What type of timber is used in leaky buildings?

Coming up in this article, you will see an outline of what H1, H2, H3, H3.1 and the different stamping on timber means… and which timbers are associated with leaky buildings, or potential leaky homes…

1 in 5 phone calls we receive will ask, “How do I know what type of timber my house (or the house i’m looking to buy) is built with?“. You can actually find out quite easily, but you do need to be able to see the woodmark stamp on the timber frame in one of your external walls:

What is treated timber and what is untreated timber?

Which timber will rot if I get leaks?

Hazard classes vary in treatment levels from 1 – 6, so depending on what you use the timber for will depend on treatment type:

H1 : The treatment level for low hazard situations where timber is not exposed to the weather. Its major use is for framing timber and interior linings. This type of timber has been used in external walls of ‘leaky buildings’, and the reason its failed is due to moisture ingress through the cladding and directly onto the timber! H1 timber also has sub-categories:

H 1.1 : Timber used in situations protected from the weather, dry in service and where resistance to borer only is required. Do not use this timber in external walls unless additional chemical treatment has been added.
H 1.2 : Timber used in situations protected from the weather but where there is a risk of moisture exposure conducive to decay (Pink or Blue in colour). Minimum standard to use in external walls. Check with council to confirm this minimum requirement has not been upgraded before building.

H2: This level is very similar to H1 but includes an insecticidal treatment to protect against termite attack… normally for use in Australia.

H3: For moderate decay situations where timber is exposed to the weather but is not in contact with the ground. H3 is also split into sub-categories.

H3.1 : Timber used outdoors above ground, exposed to the weather – generally in non-structural applications; i.e. fascia boards, weatherboards.
H3.2 : Timber used outdoors above ground, exposed to weather or protected from the weather but with a risk of water entrapment; i.e. decking, fencing and pergolas. Used in areas of high risk to water penetration, such as balconies.

H4: Used in high decay areas such as ground contact or fresh water. Generally used for fence posts and landscaping timbers.

H5: Used for severe decay hazard risks such as ground contact where conditions of severe or continuous wetting may occur. End uses for this hazard class are house piles and poles, retaining walls, crib walling and horticultural supports.

H6: This hazard class is for marine use. Wharf piles and fenders, marine and jetty components regularly immersed in seawater or estuarine ground.

Sometimes you may need to remove a small section of interior lining on an external wall to see the timber stamp on the frame. Otherwise it could be written on the original building plans.

Similar Posts:

Get a free 'over the phone' quick quote HERE

Best Value - Our home infrared 'Quick Scan' Details Here!

Do the moisture inspection results go on my LIM report? - Details Here

Thermal Imaging

Client Comments... (All testimonials can be verified as true and correct... updated for 2010)

I enlisted Dean’s services 2 days prior to “D-day” of us purchasing our first NZ home. Dean proved to be an extremely efficient and knowledgeable technician. He has a very good understanding not only of his specific field, but also of general building requirements. He was easily able to spot, and talk me through, existing as well as potential problems, and was very open to answering the myriads of questions I fired his way. Most importantly, he gave me non-biased answers, allowing me to make an objective decision regarding the purchase of a potentially leaky home. Thanks again for excellent service Dean! Simone P - Titirangi

We have lived for some time in an old weather board cottage which we have renovated over a period of years. Recently we discovered a leak, so we googled “find a leak” and found a comprehensive and detailed website of the same name. Next we spoke to Dean and an appointment was made. He was punctual, courteous and his experience was obvious. His thermal imaging equipment is ‘state of the art’ and the source leak was quickly detected.

Dean was able offer practical solutions which we can act on with confidence. As a result of this experience we would recommend the use of his skills before the sale or purchase of any property to be reassured as to the integrity of the property. Dean is personable, a superb communicator and a true professional. Maggie & David M - Waiatarua

Dean was very professional and I would highly recommend anyone that is thinking of buying a property to get thermal testing done. Fortunately it was by pure chance that I even knew these tests were available after speaking to my neighbour and he advising me. The house we were looking at had water leaks and Dean has saved me many thousands of dollars in the long run. David G - West Auckland

Dean is a very professional and friendly guy. He goes step by step through the process which is very valuable. When he finds a potential problem he immediately notified to me and discussed with me in details on what actions could be taken. Anyway no major problems were detected in the property I wanted to purchase. However I greatly advice anyone to obtain Dean's professional service to make sure the property is in a satisfactory condition. Robbie P - Glen Eden

Thank you very much for the great service, very professional and appreciated the time taken to explain the process. Very glad to know that with all the stigma that goes with plaster houses, ours is not a leaky home. The report has helped pin-point some areas for maintenance which we plan to undertake sooner rather than later..Thanks again. Heather M - Maraetai

We were a bit apprehensive about what the leak detection might find, but found Dean’s confident, friendly and very capable approach extremely reassuring. While we were greatly relieved by the findings concerning the exterior of the house, Dean’s thoroughness in looking also for internal issues uncovered a surprise bath leak. Thanks Dean for solving the mysterious odour that’s been bothering us for the last 6 months! We highly recommend Dean to anyone with even the slightest concerns regarding moisture in their homes. Kevin - West Auckland

Thank you Dean for your prompt service. I was given 2 days to have a Building inspection done which found some dampness in the house. It was well worth the money spent as Dean found some other damp issues. He was very thorough and very informative and even though there were issues with the house they were all fixable so I was then able to re negotiate the purchase price. I would recommend anyone buying a house- any type of building structure to have ’Thermo Imaging’ as part of a building inspection. Thank you once again. Maree, Glendowie

We had some concerns about a recently renovation house including a lower basement. Being nosey I popped around to join Dean on his inspection. Apart from enjoying meeting him, Dean was enormously informative, approachable & friendly, I found the technology & information I gleaned fascinating. Fortunately, we identified no significant issues with the property. It gave us great peace of mind & we can enjoy our new home knowing we have bought a dry, water tight property with with hidden surprises. Thank you Dean for your help & reassurance. To my mind it is certainly worth the modest sum versus potential costs you could incur which could also mar one of most expensive purchases of your life.. Diane - Devonport

Read 20 more testimonials Here!