Are 60 minute fire rated doorsets acceptable in a softwood frame?
The quick answer is NO, the more detailed answer is below.
In practice it is virtually impossible for a 60 minute fire test using a softwood frame, to be successful, softwood burns/chars rapidly when compared to virtually all hardwoods.
In most tests a dense hardwood is used, softwood would be accepatable if it could be supported by the appropriate test evidence.
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