Often when I talk with my friends they seem to lack insight of the necessity of proper insulation or double glazing.
Where winters are mild and short, they often are damp and summers can get hot.
With damp winters the temperature feels much colder and you're not comfortable.
Unheated damp rooms will have a lot of condensation on the windows.
Overheating in summer will drive you to the use of your heatpump to cool things down.
Insulation
Proper insulation, should tackle those problems.
The Building Code requires walls to have an R value of 1.9 (for climate zones 1 and 2.)
Other countries with moderate winter temperatures have almost double that amount (R=3.5) That means a minimum of 140mm of insulation.
Going a step further: a LOW- energy or Passive house would need about 270mm of Insulation. But that's another topic to talk about..
Aluminium windows
95% of new buildings in NZ have aluminium windows with no thermal break, that is fine for strength and nice narrow frames. This however allows the unobstructed passage of heat from inside to out.
The inside temperature of the frames will be almost the same as the outside temperature thus condensating in winter times and heating up in summer.
Elsewhere these windows are only allowed to be used for internal office separation walls.
Tackle this problem by using thermally broken aluminium windows, Installing timber or uPVC windows. Timber windows will have the best insulating properties.
Double glazing
Standard double glazing, you should think that must be good.
Yes this is an improvement but can be even better. The standard double glazing should be minimum Low E glazing, filled with argon and a low E coating. This glass can have an U-value of 1.1 and even lower.
Single glazing has an U-value of 5.6.
Double gazing comes to 2.8.
Using Low E glazing in combination with thermally broken aluminium frames will result in a more comfortable house with no condensation and less cold radiation.
To get rid of cold radiation when sitting near a window would require triple glazing, I'm not getting into that. The costs for that are too high at this moment.
U or R value
What is the difference between the U Value and the R value?
The U value is used only in measuring the insulation of windows, while the R value covers all other aspects of the home: walls, floors and roofs.
To make it more confusing: The higher the R-value the better. The lower the U-value the better.
Home Concept can calculate the proper R values of any building material or composition of materials.
