Browse Forums Heating, Cooling & Insulation 1 Oct 26, 2009 8:33 pm If I add R3 to my brick veneer uninsulated walls (making them R3.5 in total) what energy saving will I have? I assume the calculation will be different due to heat transfers vertically a lot easier than horizontally? I have 85m2 wall & 24m2 single glazed windows electricity @ 23c/kWh...SA rates! On my windows I have Roman blinds in the reveal & also roller shutters (dunno what or how much R value the can be rated to) Re: Wall insulation & window insulation 2Oct 27, 2009 8:21 am The heat loss calculations are based on the idea that you need to replace heat as fast as it is lost. This is not quite how people operate their houses. It is difficult to do a $calculation because it depends on how much energy you already use for artificial heating or cooling to keep to within your comfort levels. Most people don't leave the thermostat on one setting and it leave it all day. They will only switch heating or cooling when temperatures go beyond their tolerable limits. The more efficient your house, the longer it takes for the temperature to drift outside those parameters and your heating/cooling needs decrease. Read this for an analogy: viewtopic.php?p=278870#p278870 The ceiling theoretically loses more heat because of natural convection. But it also benefits the most from insulation because it's R value is already much lower than walls (i.e. only a bit of plasterboard). This is a dollar calculation based on some assumed conditions (you need to modify this according to your situation): viewtopic.php?p=280294#p280294 Re: Wall insulation & window insulation 3Oct 27, 2009 6:59 pm So to get a good / accurate picture, I need to record my energy use to heat or cool my house for an hour at a constant temp ( I guess heat as that wouldn't include radiant heat buildup) with a known outside temp? I am currently on reverse cycle, so I would need to work out it's kW output / kW energy used also. I could then work out my heating & cooling energy use & insulation effects I am saying that double brick has similar thermal performance due to thermal mass effect. It will be still very interesting to see the state of your framing after 10-15… 10 29659 Hi all, Just wondering if anyone had suggestions on installing/replacing wall insulation on an external wall which doesn't have wrap, our miners cottage being constructed… 0 4931 1 19708 |