Cornerstone Building (CNR) with a notable insider buy this week when director George Ball bought 25,000 shares at $14.65, a more than $366K investment. This is the first open market buy in 2021 and follows other notables in May 2020. CNR has also seen some bullish options flow including 1500 March 2022 $15 calls bought last week for $2.65/$2.70. The $1.89B company has traded well in 2021 up over 60% and pulling back about 25% from 52-week highs recently. Shares are back at a big volume node and prior breakout level. A move above $16.50 key to resuming the longer-term uptrend. Shares trade 9.87X earnings, 0.40X sales, and 2.83X cash with double-digit growth. CNR specializes in external building products for the commercial, residential, and R&R markets. Their product lineup includes areas like fiberglass doors, siding, aluminum gutters and more. CNR has benefitted from the boom in housing over the last several years and demand for new builds as supply remains low. They have been a serial acquirer with smaller M&A deals focused on building out their expansive product solutions while investing in markets like vinyl windows that are poised to grow. CNR is focused on net debt reduction now and expanding their automation solutions to drive margin expansion. Analysts have an average target for shares of $17 with a Street High $21 from Barclays who likes how CNR continues to focus on efficiency improvements and pricing to drive further through-cycle margin expansion, amidst a robust residential backdrop. Short interest is 2.66%. Hedge fund ownership fell 1.5%. Caas Capital a top buyer of stock.