More efficient air conditioning


We hear a lot from customers who built a new home and were convinced that if they insulated it properly, made it open and airy and positioned it in a way to capture the breezes that air conditioning wouldn’t be needed. They normally last one summer before we hear from them for a quote. If you live in Brisbane, air-conditioning is a necessity. Yes, the attributes listed above are important – but it simply gets too hot where we are to not have some form of air-conditioning. In saying that though, its still important that you take into account a few things, to work along with your air-conditioning: Insulation – whilst most houses these days are insulated, there are still a few out there that aren’t, and we would always recommend insulating your home – specifically any western facing sides of the house, as they cop it from the afternoon sun. Whirly Birds –Unbeknownst to a lot of people, if you have ceiling insulation laid on top of your ceiling – you still have a lot of heat between the insulation and the top of the roof that can’t escape anywhere, and that’s why we recommend whirly birds. These days, you can get solar whirly birds that spin at about 20 x the rate of the old school metal ones everyone is used to seeing.  If you do not have anything, then the temperature in the roof will be much higher, and the ducted system must work a lot harder to get to temperature. This will result in a loss of efficiency and will increase running costs. Not only that, it will be hotter in the house as all that heat is trapped between the roof and the insulation, and you get a baking effect between the roof and the rooms below. In extreme cases we have found that if the roof space doesn’t have some way to get heat out of the roof, a ducted system can condensate inside the roof space because the temperature of the roof is too high comparative to the temperature inside the duct, exactly like when you pull a can of coke out of the fridge and it sweats. We have seen this is in particularly low pitch roofs, along with in metal frame houses. Some may say why don’t you upgrade to a higher rating duct (like r1.5 or higher), but the issues we have seen aren’t related to the duct work but more so everything else; the indoor unit itself, the plenums, the joiners and zone motors can be a problem when you have a poorly insulated roof space. The cost of solar whirly birds is relatively affordable, you can get a decent one installed for around $5-600. Whilst we don’t offer installation services ourselves, we can recommend those who do, or if you are handy you can even DIY (although we don’t recommend as the idea of cutting a hole in the roof is a scary one especially if its not sealed properly). We have done a before and after test at a customer’s house and found a difference of about 5 degrees in the same roof, before and after 2 solar whirly birds were installed. Finally, the other thing to do is keep in mind your window coverings, particularly on the western sides of the house. For instance, on a 34 degree summers day turning the air conditioner on and leaving your window open isn’t the best of ideas. You would be surprised how much heat-load is reduced by getting better curtains, window tinting etc or even just closing them on a hot day before that sun bakes in. Of course, if you get us out to quote your property for air-conditioning, we are happy to discuss what other things you can do to help its efficiency. After all what is the point of spending all this money if it’s going to be wasted!