Hi there,
First of all, thank you for this amazing resource. I have a couple of questions about furring channel installation to an existing concrete block wall.
1. What is the difference between a furring channel, which requires a fixing clip, and a top hat channel, which can be direct fixed?
2. Some references I've looked at have the furring channels installed vertically, while others have a additional channels running horizontally above and below (ie Villaboard Installation Guide page 10). I can't find any clear instructions on the layout for installation other than spacing requirements. Does this differ based on the type of sheeting used i.e. Gyprock Aquachek 10mm?
Thank you