Redwood standards have long been established by the Redwood Inspection Service( RIS). The most used decking grades have always been Construction Common and Construction Heart. Recently there have been an influx of proprietary grades. The question is what are they and how do they hold up to the high standards set by the RIS? Construction Common, Premium, Top Choice, and Superior Common grades are all graded to the high standards of the Construction Common grade set forth in the RIS grade book. Construction Heart, Deck Heart , and Superior Heart are interchangeable for the Construction Heart grade. There are many other grades on the market that should be looked at closely before accepting them as a Con/Common or Con/Heart grade, as the amount of acceptable downfall has been drastically increased.