I purchased a Goldaire heater to mount on the wall of our laundry. The wall is gib with paint.

The instructions say "wall mounted heaters are only to be mounted on heat resistant walls that comply with current AS/NZD specifications & building regulations".

Questions

 

1. How do I know if I have a heat resistant wall? I found that specification but it costs about $90 to buy.
2. Ignoring standards for a minute, is it generally considered safe to mount a 1000W heater to a painted gib wall? I left the heater on high for an hour, the struts that attach to the wall didn't even get warm.