Browse Forums Heating, Cooling & Insulation 1 Aug 14, 2010 5:36 pm Hi All Our house that we are building is around 240sqm of living area near the coast in Perth. It has 4 bedrooms, HT, Activity room and a large open plan living area. We are getting the double brick walls insulated with rockwool , anticon (sarking) in the roof and R3.5 insulation in the ceiling (I know we left the windows as standard but we ran out of money). My question is, due to the fact that we are getting the house so well insulated, do we need to get a 15.5kw ducted split system as recommended by a few aircon suppliers or can we get away with installing a smaller 12.5kw system? Thanks in advance for your input. Re: How does insulation effect air conditioning? 2Aug 14, 2010 8:01 pm Hard to answer. A proper A/C installer does a heat load calculation. Based on the effects on direct sun and air temperature they can work out home much heat enters the building. This accounts for the amount of shading on walls and windows, the presence of radiant barriers and also insulation. They can then conclude how much heat enters given the area of the house in W/m2. Then they work out how much of the house you want to condition simultaneously. This then gives you the size of the AC unit to remove this heat. Most times these guys just do a rough calc assuming about 100W/m2 of conditioned area without taking in account of any of the above. The problem is that an undersized unit will run continuously (straining the unit) and an oversized unit frequently switches on and off trying to maintain the target temp (which is energy inefficient). Anybody know any good and reasonably priced Air conditioning contractors/companies that could install a ducted air conditioning system in the Central Coast NSW for a small… 0 8996 0 6304 How do you remove one of these ceiling air con vents? And is it possible to disconnect the duct joined to the vent from inside the house, without going into the roof cavity? 0 5947 |