AKRON, OHIO (Nov. 8, 3:10 p.m. ET) — Average North American selling prices for polypropylene and suspension PVC resin each bumped up 2 cents per pond in October.

The 2-cent PP move means that prices now are up a total of 3 cents per pound in September and October combined. Some buyers reported seeing only 1.5 cents in increases per month, but the two-month total settled out at 3 cents.

The increases come after prices had tumbled a total of 27 cents per pound between May and August. Combined with early-year prices increases, Regional PP prices now are down a net of 2 cents from where they started the year – a drop of about 2 percent.

The October increase resulted from tighter supplies of both PP resin and propylene monomer feedstock, as well as relatively strong PP demand growth in North America, market sources said.

Through September, U.S./Canadian PP sales were up just under 3 percent, according to the American Chemistry Council in Washington. Domestic sales growth of almost 4 percent was dampened by a 15 percent decline in export sales.

Regional PP demand “should be balanced through the rest of the year,” according to Scott Newell, a market analyst with Resin Technology Inc. in Fort Worth, Texas. “It could come down a little bit, but growth still should be positive for the year.”

Price increases of 5-7 cents per pound have been nominated for Nov. 1 for propylene monomer, and resin prices have followed monomer prices almost in lockstep for the last couple of years. But Newell said that trend could be changing, as resin markets grow tighter and operating rates approach 90 percent.

“We’re seeing producers push for [profit] margin expansion beyond the monomer price,” he said. “They’d been trying unsuccessfully for two or three years, but heading into 2013, they’re trying to change contracts that are based on monomer prices.”

“Resin supply is tightening, and that helps [PP] producers’ chances” of growing margin, Newell added.

In the short-term, North American PP supplies could be affected by the temporary closings of more than 1.5 billion pounds of combined capacity at plants operated by Braskem Americas in Marcus Hook, Pa., and by Phillips 66 Corp. in Linden, N.J. Both plants went down in advance of Hurricane Sandy, which hit the U.S. East Coast on Oct. 29, bringing with it high winds, heavy rains and flooding.

As of Nov. 8, both of those plants had regained electrical power, but neither was producing PP resin. On the Phillips 66 website, officials said that normal operations at its Bayway Refinery – which includes the PP plant – should resume in two to three weeks.

Through September, U.S./Canadian sales of PP into injection molded cups and containers were up more than 23 percent, making that category one of the region’s fastest-growing PP end markets. Sales of PP to compounders in the region were up almost 15 percent.

In PVC, producers in October were able to push through 2 cents of a 3-cent increase they were seeking for that month. The increase marks the second in as many months, following a 3-cent hike that took hold in September.

A Texas-based PVC buyer said that although demand was good in October, it’s been slowing lately. A dramatic drop in export prices and a lower-than-expected increase in ethylene feedstock also prevented the full 3-cent move from going through, he said.

The 3-cent move in September had put prices back to their Jan. 1 levels. The 2-cent October hike now puts them in positive territory by about 2 percent.

U.S./Canadian PVC sales were up almost 6 percent through September, with domestic growth of almost 7 percent slightly lessened by export growth of more than 4 percent.

The increase in domestic PVC sales is proof that the U.S. housing market is rebounding after several difficult years. Sales into the industry’s flagship rigid pipe and tubing end market jumped 10 percent through September, while sales of PVC into siding and related uses grew almost nine percent. Sales into extruded windows and doors grew at an even faster rate of almost 24 percent.

Construction-related sales made up almost 61 percent of total domestic PVC sales during that nine-month period.