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Climate Change could be damaging your home: here’s what you need to know, and what can be done.

Uncategorized Oct 22, 2020

Hi there. What are your first thoughts when I mention the word climate change? Do you agree with it or do you step outside your front door and you think to yourself spring and summer, it's not just as pleasant as when you were perhaps a child? Well, these extreme weather events, think of bush fires or extreme water events, this encapsulates the concept of climate change, and we all know the famous Swedish environmental climate activist, Greta Thunberg, presented her famous series of speeches in 2018 and '19 talking about the dire impact of climate change if we don't do something about it.

So that brings me to what we're going to be talking about in this week's live stream, and this is some of the impacts of extreme weather events that can affect our homes and cause damage in particular to timber and timber incorporated into not only new building construction but all sorts of different environments where timber is used. The jumping-off point for me deciding to talk about this week is this wonderful paper which came out at the beginning of October talking about the impact of extreme weather events on timber, and the reason I thought that this would be a very good topic to focus on is not a week goes by without someone ringing me up to say, "Help, my new home construction, all the timber framing or truss is showing lots of examples of mold and weathering."

Oftentimes, people tell me that they have consulted with their builder and the builder has gone to the timber industry and the timber industry has come back saying, "No, you don't have to be worried about that. That is just staining of the timber, and unless it's caused structural decay of the frame or truss, it's nothing to worry about." Well, I'm here to say that that is absolute nonsense and doesn't have any scientific credibility. Yes, I appreciate the brown and white rot fungi are those fungi that cause structural decay, but the very presence of other types of mold on your built framing is a serious health concern and we're going to be going through some of these today.

As well, I'm going to be talking about the eight areas of a home that you need to look out for to monitor for the impact of climate change all around your home. Now, the topic of today is, is climate change damaging your home? What are we talking about here? Well, we're talking essentially about warmer and wetter environments, that is warmer climate and wetter climate and then drier summers. To kick this off, I'm going to drill into that academic paper that came out at the beginning of October which puts all of this into some perspective.

To start this, we're talking about warmer weather winters, warmer dryer summers, which are a significant consequence of climate change. What the academic scientists are saying is that this change to the climate means that there is an increase in the severity of microbiological attack of exposed timbers, and what this means is that this affects not only new home construction, but homes that have already been constructed. The International Energy Agency has also stated that over the next 40 years, there are 230 billion square meters of new buildings predicted to be built, and this has an area of the size of Paris being added every single week.

Now, just think about it, the area the size of Paris in new building constructed over the next 40 years. That's a lot of potential for sick building syndrome to occur to be associated with some of these dwellings. I want to show you how you can protect yourself, but I want to get back to something called the Scheffer index in this particular research, because it applies worldwide, and this Scheffer climate index is a measure of how the monthly rain relates to temperature, and the British researchers have done the Scheffer index for the United Kingdom, but I wanted to show it for Australia.

What we can see is that at coastal areas, right around in the blue and green areas, these are those areas which show significant rain and temperature shifts, and this allows us in a sense to predict those areas of Australia that are more probable going to have a decay index associated with them. We have to respect the fact that as there is an increasing risk of climate change, this is going to lead to more rapid potential decay of all types of building elements, but particularly timber building elements, and so we can now look at some other aspects of the research as well and we have to look at the fact that climate risk results in faster rates of timber decay, which of course could lead to serious economic loss.

So these are the implications of climate change. Obviously, depreciation in asset value of buildings and there may need to be replacement due to safety or aesthetic concerns, and of course, there could be a loss of wooden cultural artifacts. Now, what can we actually look at in terms of potential solutions to climate change? Well, we need to put an increased effort into examining and assessing building designs to minimize the impact of water damage on the built environment. We also need to make better choices about more durable woods used in construction. Most importantly, we need effective wood preservation and preventative strategies, especially when timber framing has become mold affected.

We can't just cover it up with plasterboard and new paint and say the problem's hidden, it's not there, don't worry about it. Brown and white-rot fungi weren't there. It hasn't decayed significantly enough to damage the structural integrity. That's just not true. We know from the World Health Organization 2009 publication that mold affects respiratory health and increasingly we see that mold affects immune status as well. So of course, building mold into a building is just bad idea. But if we go back to this slide, we can see a hazard map of Australia for timber under the influence of decay fungi, and this is from allied research from the timber industry itself, and remarkably, you can see that the graph of the predicted fungal timber decay and the Scheffer index overlaps quite significantly.

Now, I also want to now tell you the eight areas that you should be looking at and point out some typical examples of building elements and areas in a property that you must be regularly monitoring and investigating. So this is the eight-point visual inspection checklist for what's generally termed leaky building syndrome. So look out for sagging of ceiling linings. Check for corrosion of fixings and fittings, and if you've got carpet and you think it's damp or you use a moisture meter and prove that it's damp, well, check the carpet grippers to see if they're rusting. That is an example of corrosion.

Uneven floor surfaces are a dead giveaway that there are water problems, and that again, if climate change is leading to increased levels of rain, that's going to lift floors. Obviously, look out for visible evidence of mold or fungi or evidence of mold being a musty smell. Look for swollen architraves or skirting boards, and of course, staining or discoloration of surfaces, including damage or efflorescence coming out of concrete flooring, and look for staining and rotting of carpets.

Typical areas where to look in a property are any flat roofs or roofs that have concealed guttering. Concealed plumbing is a problem in flat roofs and it leads to a build-up of water that may not be able to escape adequately. Examine the flashings around windows. Of course, decks over living areas are a big problem, as are decking and outdoor areas in apartments with planter boxes built into them. Oftentimes, water can't escape properly and then percolates through downstairs.  Another problem that you must be aware of is any ground floor home or apartment where the ground level outside is higher than inside could be a big problem. So the solution here is to inspect, assess, and monitor for better buildings.

But you're probably thinking checklists are great, but what happens when I actually have a problem? You might have a dispute. You might need to prove to someone that some of the timber building elements within your property are actually decaying. Well, that's when companies like mine come into play and you can use things like tape lifts. Even if we're too far from you, you can purchase type lifts and you can have these used. I'm going to show you exactly what this looks like for a property that I inspected earlier in the week. If I go to this now, this particular timber reveal in a apartment had been leaking from the upstairs deck planter box.

Now, the issue here is when we use these tape lifts to apply them to the surface, you can actually see that I've got a small microscope image of what this tape lift looks like, and you can see it's pulled off some of the wood, which has shown up in black, but at magnification, you can see all of those mold spores and that really is a big problem because those mold spores easily become airborne and are a serious respiratory health risk and also can cross-contaminate a home very easily and that is something that we just don't want.

This is an example of an internal window frame that has been water damaged from a slow but persistent leak from the above apartment. The outdoor deck above has a planter box that has been leaking, through the ceiling and onto the window frame. The body corporate has suggested that the mould hasn't caused structural decay and can be wiped off. 

Here's another photo showing the occupants needing to use an empty plastic container to collect the dripping water.  Notice all the wall staining to the right hand side of the photo.  Tape lifts are an easy to use tool to assess the level of contamination under the microscope and produce detailed reports of the extent of mould damage. 

Back at the lab, I can look at the tape lift under the microscope to see how bad the water damage has been?  These are normally assessed at x400 times magnification.  Tape lifts are an excellent tool for water damage and mould assessment of suspect surfaces.

Look at all those mould spores!  That's what is on the timber window architrave surface below the plastic dish.  Those mould spore seasily become airborne and can cross-contaminate other areas of the home - far away from the initial water leak.

Now at low power (x100), we can also see the wood fragments (in black) and all the tiny mould spores surrounding the timber.  It's the mould spores we need to be concerned about! 

So I hope today has shown you the potential impact of climate change and shown you that it can affect everyone and that is quite a serious consequence of fluctuations in rainfall and temperature. In any case, my name is Dr. Cameron Jones. I'd encourage you to follow and subscribe to any of my social channels by using @drcameronjones. In any case, have a great week. I'll see you next week. Bye for now.


YouTube Video:


Pham, Lam & Ekambaram, Palaneeswaran & Stewart, Rodney & Sahin, Oz & Bertone, Edoardo & de Faria Correa Thompson Flores, Juliana & Franklin de Oliveira, Guilherme. (2018). Resilient Buildings: Informing Maintenance for Long-term Sustainability.

Curling, S.F., Ormondroyd, G.A. Observed and projected changes in the climate based decay hazard of timber in the United Kingdom. Sci Rep 10, 16287 (2020).

Impact and Assessment of Moisture-affected, T. (2020). Impact and Assessment of Moisture-affected, Timber Construction | WoodSolutions. Retrieved 17 October 2020, from

Dedesko, S., & Siegel, J. A. (2015). Moisture parameters and fungal communities associated with gypsum drywall in buildings. Microbiome, 3, 71.

Time running out for construction sector to cut energy use, meet climate goals – UN. (2020). Retrieved 17 October 2020, from

Manual 4 – Decay above- ground; Technical Manuals For Timber Service Life Design Guide. (2020). Retrieved 17 October 2020, from

WHO guidelines for indoor air quality : dampness and mould. (2009). Retrieved 17 October 2020, from


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