The proven Zacks Rank system focuses on earnings estimates and estimate revisions to find winning stocks. Nevertheless, we know that our readers all have their own perspectives, so we are always looking at the latest trends in value, growth, and momentum to find strong picks.Looking at the history of these trends, perhaps none is more beloved than value investing. This strategy simply looks to identify companies that are being undervalued by the broader market. Value investors use a variety of methods, including tried-and-true valuation metrics, to find these stocks.In addition to the Zacks Rank, investors looking for stocks with specific traits can utilize our Style Scores system. Of course, value investors will be most interested in the system's "Value" category. Stocks with "A" grades for Value and high Zacks Ranks are among the best value stocks available at any given moment.One company to watch right now is Beacon Roofing Supply (BECN). BECN is currently sporting a Zacks Rank of #2 (Buy), as well as an A grade for Value. The stock is trading with P/E ratio of 11.28 right now. For comparison, its industry sports an average P/E of 21.47. Over the past year, BECN's Forward P/E has been as high as 17.76 and as low as 10.16, with a median of 13.10.Value investors also use the P/S ratio. The P/S ratio is is calculated as price divided by sales. This is a prefered metric because revenue can't really be manipulated, so sales are often a truer performance indicator. BECN has a P/S ratio of 0.59. This compares to its industry's average P/S of 0.93.These figures are just a handful of the metrics value investors tend to look at, but they help show that Beacon Roofing Supply is likely being undervalued right now. Considering this, as well as the strength of its earnings outlook, BECN feels like a great value stock at the moment. Infrastructure Stock Boom to Sweep America A massive push to rebuild the crumbling U.S. infrastructure will soon be underway. It’s bipartisan, urgent, and inevitable. Trillions will be spent. Fortunes will be made. The only question is “Will you get into the right stocks early when their growth potential is greatest?” Zacks has released a Special Report to help you do just that, and today it’s free. Discover 5 special companies that look to gain the most from construction and repair to roads, bridges, and buildings, plus cargo hauling and energy transformation on an almost unimaginable scale.Download FREE: How to Profit from Trillions on Spending for Infrastructure >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Beacon Roofing Supply, Inc. (BECN): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research