Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of building materials producer Owens Corning (NYSE:OC) got nailed as much as 4.9% following release of its fiscal-first-quarter earnings.

So what: Revenue for the first quarter slipped 5.2% to $1.28 billion while adjusted earnings were flat at $35 million, or $0.29 per share. Analysts had been expecting $1.34 billion in revenue along with $0.35 in EPS, so it missed by a good clip. Investors rarely like it when earnings miss, no matter how good the outlook.

Now what: CEO Mike Thaman blamed the shortfall on weaker than expected roofing volumes. Owens Corning expects the roofing business to pick up throughout the balance of the year. The company anticipates new construction in housing to improve this year and possibly some flat to improved reroofing demand. However, Owens Corning cautions, "The first-quarter volume weakness adds some additional risk to the company's financial outlook." That statement is less than confidence inspiring.

Thaman also stated, "The current outlook for our markets and the momentum in our Insulation and Composites businesses support another strong year of earnings growth." This is again expected upon strength in U.S. home construction. Owens Corning also expects its insulation business to benefit from "improved pricing and operating leverage."

Based on analyst estimates, Owens Corning trades at a forward P/E of 17 based upon its current share price and estimated earnings per share of $2.46 for the fiscal year ending December 2014.