26 DUNN CONSTRUCTION CO. / BIRMINGHAM, ALA.

Through its subsidiaries, MMC and Bayou Concrete, this company supplies ready-mix concrete and related construction products. It services the industrial, commercial, and infrastructure markets in the Southeast. www.dunnconstruction.com

27 PAVESTONE / DALLAS

Dan Mulhern, president of Veneerstone, a sister company of Pavestone, became president of the Masonry Veneer Manufacturers Association early in 2011. Pavestone became a subsidiary of the Oklahoma Publishing Co. in 2010. www.pavestone.com

28 IRVING MATERIALS INC. / GREENFIELD, IND.

This employee-owned corporation has four regional operation centers. It provides concrete, aggregates, and related products to the construction and building industries. www.irvmat.com

29 IMPULSORA TLAXCALTECA / MEXICO CITY

This company produces materials for manufacturing, freight, and installing precast concrete structures. It is a leading manufacturer of precast concrete structures, construction rehabilitation, railways, and concrete sleepers or railroad ties. www.itisa.com.mx

30 VALMONT INDUSTRIES INC. / OMAHA, NEB.

Operating in four business units, this company's Utilities Support Structures division produces concrete and steel poles and other structures used by utilities. The U.S. accounts for 55% of its revenue. www.valmont.com

31 CARDI CORP. / WARWICK, R.I.

This company is the largest provider of construction services in Rhode Island, specializing in commercial concrete and highway and heavy construction. It provides ready-mix concrete and aggregates throughout the Northeast U.S. www.cardi.com

32 HARPER INDUSTRIES / PADUCAH, KY.

Founded in 1949, this company is comprised of eight operating companies, including Metro Ready Mix Concrete of Nashville, Tenn., which operates 14 plants. Harper is also pursuing projects in the alternative fuel markets. www.harper1.com

33 VICAT GROUP / STOCKBRIDGE, GA.

This French company experienced an overall 6.2% increase in revenue in 2010. Its U.S. concrete businesses are National Ready Mixed Concrete Co., of Encino, Calif., and Kirkpatrick Concrete Inc., of Birmingham, Ala. www.vicat.com

34 MEADOW VALLEY CORP. / PHOENIX

With operations concentrated in the Las Vegas and Phoenix areas, this producer specializes in heavy-highway construction. Its materials division provides products for both its own projects and third parties. www.meadowvalley.com

35 LATTIMORE MATERIALS / MCKINNEY, TEXAS

Family-owned since 1961, minority owner Holcim acquired the entire company in early 2011. Operations include seven aggregate mines, 26 ready-mix concrete plants, four rail terminals, and more than 400 ready-mix and haul trucks. www.lmctx.com

36 NEW ENTERPRISE STONE & LIME / NEW ENTERPRISE, PA.

This company specializes in highway construction and construction materials production. It has several subsidiaries throughout the U.S. and operates several ready-mix plants in central Pennsylvania. www.nesl.com

37 CEMSTONE PRODUCTS CO. / MENDOTA HEIGHTS, MINN.

This producer has operations in Minnesota, Western Wisconsin, and Northern Iowa. It hosts the annual Run for Others five-kilometer race to support Habitat for Humanity. www.cemstone.com

38 METROMONT CORP. / GREENVILLE, S.C.

Specializing in precast, this company has facilities in Greensville, S.C., Atlanta, Nashville, Tenn., Charlotte, N.C., Richmond, Va., and Bartow, Fla. It acquired Royal Concrete Concepts in West Palm Beach, Fla., in January 2011. www.metromont.com

39 CONCRETE SUPPLY CO. / CHARLOTTE, N.C.

Merger of three ready-mix producers more than 50 years ago created this company, which operates more than 30 plants in South and North Carolina. It provides building materials for the commercial and residential sectors and concrete pumping services. www.concretesupplyco.com

40 FABCON INC. / SAVAGE, MINN.

This producer has operations in four states: Minnesota, Indiana, Ohio, and Pennsylvania. It manufactures concrete wall panels, highway traffic barriers, columns, and sound walls. www.fabcon-usa.com

41 HIGH CONCRETE GROUP / DENVER, PA.

This company operates in Illinois, New Jersey, Pennsylvania, and Ohio. It is a leading producer of architectural and structural wall panels, as well as the nation's largest producer of precast concrete parking structures. www.highconcrete.com

42 GATE CONSTRUCTION MATERIALS GROUP / JACKSONVILLE, FLA.

Manufacturer of architectural precast concrete, prestressed hollow core slabs, and transportation and infrastructure components. One of few producers with a blog on its website. www.gateprecast.com

43 TINDALL CORP. / SPARTANBURG, S.C.

This company designs, manufactures, and erects precast and prestressed concrete systems. Last year it completed a new Armed Forces retirement home in Gulfport, Miss., which was damaged by Hurricane Katrina. www.tindallcorp.com

44 A&A READY MIXED CONCRETE / NEWPORT BEACH, CALIF.

This is the largest family-owned supplier of ready-mixed concrete in California. Founded in 1949, its website extols, “We are concrete experts with the passion, the expertise, and the guts to take on any job.” www.aareadymix.com

45 ERNST ENTERPRISES / DAYTON, OHIO

Third-generation family-owned producer operates in Ohio, Indiana, Kentucky, and Georgia. It supplies ready-mixed concrete and provides concrete pumping services for the residential, commercial, industrial, and public sectors. www.ernstconcrete.com

46 THE MONARCH CEMENT CO. / HUMBOLDT, KAN.

Company provides ready-mixed concrete and other materials in Kansas, Iowa, Nebraska, Missouri, Arkansas, and Oklahoma. Includes Monarch Portland Cement and Monarch Masonry Cement. www.monarchcement.com

47 CONTINENTAL MATERIALS CORP. / CHICAGO

Dividing its products between construction and HVAC, this company's construction products segment accounts for half of its sales. Ready-mix concrete and aggregates are produced through subsidiaries Castle Concrete Co. and Transit Mix Concrete. www.continentalmaterials.com

48 THOMAS CONCRETE INDUSTRIES / ATLANTA

A subsidiary of Swedish-based Thomas Concrete Group AB, this is one of the Georgia's largest ready-mix producers. In less than 20 years, it has grown from three plants to 42 in three states. www.thomasconcrete.com

49 HOLIDAY ROCK / UPLAND, CALIF.

With more than 70 years in business, this is one of the largest independent producers of aggregates and concrete in the U.S. It currently has seven aggregate plants and 13 ready-mix concrete plants servicing the West Coast. www.holidayrock.com

50 TEICHERT, INC. / SACRAMENTO, CALIF.

This company's construction materials segments produce a wide variety of building materials. Its precast division manufactures products for underground utilities and infrastructure projects. www.teichert.com