with the introduction of the property manager and the way that archicad uses building materials in v21 now I was just wondering is there an online resource I can use to obtain the accurate physical properties for various building materials (stone, timbers, glass, rubber, plastic, coated metal, insulations etc etc... I can input into ArchiCADs following dialouges:
You already have that, but it is tied to Building materials, which is the way it should be. Property manager and properties there are applied to entire element. For example wall is composed from several building materials, and they have physical properties.
Values are written in a file called materials.xml, which you can find in Graphisoft/ArchiCAD 21/Addons/Energy Evaluation folder. You can Edit that file and add your materials, but be carefull with formating. Real world valčues you have to obtain from manufacturers of building materials.