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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 10-K

(Mark one)

For the fiscal year ended December 30, 2000

OR

For the transition period from                to                

Commision file number 0-3701

VALMONT INDUSTRIES, INC.
(Exact name of registrant as specified in its charter)

Registrant's telephone number, including area code: (402) 963-1000

Securities registered pursuant to Section 12(b) of the Act: None

Securities registered pursuant to Section 12(g) of the Act:
Common Stock; $1.00 par value
Preferred Share Purchase Rights

    Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Sections 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes /x/  No / /

    Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. Yes /x/  No / /

    At March 2, 2001 there were outstanding 23,336,731 common shares of the Company. The aggregate market value of the voting stock held by non-affiliates of the Company on March 2, 2001 was $262,070,000.

DOCUMENTS INCORPORATED BY REFERENCE

    Portions of the Company's annual report to shareholders for the fiscal year ended December 30, 2000 (the "Annual Report") are incorporated by reference in Parts I and II, and portions of the Company's proxy statement for its annual meeting of shareholders to be held on April 26, 2001 (the "Proxy Statement") are incorporated by reference in Part III.

VALMONT INDUSTRIES, INC.

Annual Report Pursuant to Section 13 or 15(d)
of the Securities and Exchange Act of 1934
For the Fiscal Year Ended December 30, 2000

TABLE OF CONTENTS

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PART I

ITEM 1. BUSINESS.

(a) General Description of Business

    Valmont Industries, Inc., a Delaware Corporation, was incorporated on March 8, 1946 and together with its subsidiaries (the "Company" or "Valmont") is engaged in the Infrastructure and Irrigation businesses. The description of Valmont's businesses set forth on pages 10 through 25 of the Company's 2000 Annual Report is incorporated herein by reference. The Company entered the Irrigation market in 1953 from its manufacturing location in Valley, Nebraska. The Infrastructure segment began producing and marketing engineered metal structures in the early 1960's.

    Valmont has grown internally and by acquisition and has also divested certain businesses. Valmont's business expansions during the past five years include (i) the 1996 acquisitions of TelecCentre, S.A., a French manufacturer of communication towers, and of Valmont Mastbau, KG, a German manufacturer and distributor of pole structures for the lighting market, (ii) the 1997 construction of a new coatings plant in West Point, Nebraska, (iii) the 1997 formation of a 70% owned joint venture with a Brazilian manufacturer of mechanized irrigation equipment, (iv) the acquisition of two coatings facilities in Tualatin, Oregon and in Lindon, Utah in January of 1998, (v) the expansion during 1998 of facilities in Siedlce, Poland, (vi) the acquisition during 1998 of two coatings facilities in Long Beach, California and Tulsa, Oklahoma and the purchase of Cascade Earth Sciences, Ltd., a firm providing consulting services for environmental and wastewater management projects headquartered in Albany, Oregon, (vii) investment in two retail irrigation outlets during 1999 in California and Colorado, (viii) the 1999 investment in an irrigation manufacturing facility in McCook, Nebraska and (ix) the 2000 acquisitions of four coatings facilities in Minneapolis, Minnesota; Chicago, Illinois; Los Angeles, California; and Sioux City, Iowa; an aluminum pole manufacturing plant in Minneapolis, Minnesota; and a tubing business in Waverly, Nebraska. Divestitures during the past five years include the January 1997 cash sale of the stock of Valmont Electric, Inc., a lighting ballast manufacturing business and the first quarter 1999 sale of stock of an investment in an irrigation technology development business. Divestitures in 2000 included the closure of a composite pole plant in Gunnison, Utah; the sale of certain assets of a communication tower business in France; and the rolled cylinder business in Tulsa, Oklahoma.

(b) Operating Segments

    The Company has two reportable segments:

    Irrigation:  This segment consists of the manufacture and distribution of agricultural irrigation equipment, tubular products and related parts and services; and

    Infrastructure:  This segment includes the manufacture and distribution of engineered metal structures and coating services for the lighting, utility and wireless communications industries.

    In addition to these two reportable segments, the Company has other businesses that individually are not more than 10% of consolidated sales. Amounts of revenues, operating income and total assets attributable to each segment information for each of the last three years is set forth on page 49 of the Annual Report and incorporated herein by reference.

(c) Narrative Description of Business

Principal Products Produced and Services Rendered.

    The information called for by this item is incorporated by reference to pages 10 through 25 in the Company's Annual Report.

Suppliers and Availability of Raw Materials.

    Hot rolled steel coil, zinc and other carbon steel products are the primary raw materials utilized in the manufacture of finished products for the Infrastructure and Irrigation segments. These essential items are purchased from steel mills, zinc producers and steel service centers and are readily available. It is not likely that key raw materials would be unavailable for extended periods and the Company is not dependent on any one supplier for any key raw material commodity.

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Patents, Licenses, Franchises and Concessions.

    Valmont has a number of patents for its manufacturing machinery, poles and irrigation designs. The Company also has a number of registered trademarks. Management believes the loss of any individual patent would not have a material adverse effect on the financial condition of the Company.

Seasonal Factors in Business.

    Sales can be somewhat seasonal based upon the agricultural growing season and the infrastructure construction season.

Customers.

    The Company is not dependent for a material part of its business upon a single customer, or upon very few customers, the loss of any one of which would have a material adverse effect on the financial condition of the Company.

Backlog.

    The backlog of orders for the principal products manufactured and marketed was approximately $150.5 million at the end of the 2000 fiscal year and $129.9 million at the close of 1999 fiscal year. It is anticipated that most of the backlog of orders will be filled during fiscal year 2001. At year-end, the backlog by segment was as follows (dollar amounts in millions):

Competitive Conditions.

    In the Infrastructure segment, Valmont is a major manufacturer and supplier of engineered metal structures to the lighting and traffic, utility and wireless communication industries and supplies custom coating services. The Irrigation segment involves the development, manufacture and distribution of mechanized irrigation equipment, tubular steel products and related products for both the U.S. and international markets. The Company also manufactures and distributes machine tool accessories and industrial fasteners. The Company has significant competitors in each of its industry segments. The key competitive strategy used by the Company in each segment is one of high quality and service.

Research Activities.

    The information called for by this item is incorporated by reference to the "Research and Development" on page 48 in the Company's Annual Report.

Environmental Disclosure.

    The Company is subject to various federal, state and local laws and regulations pertaining to environmental protection and the discharge of materials into the environment. Although the Company continues to incur expenses and to make capital expenditures related to environmental protection, it does not anticipate that future expenditures will materially impact the financial condition of the Company.

Number of Employees.

At December 30, 2000, the Company had 5,503 employees.

Geographic Areas.

Valmont's international sales activity encompasses over one hundred foreign countries. The information called for by this item is incorporated by reference to "Summary by Geographical Area" on page 49 in the Annual Report.

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ITEM 2. PROPERTIES

    The Company's corporate headquarters are located in a 35,000 square foot leased facility in Omaha, Nebraska, under a lease expiring October, 2008. The headquarters of the Company's operating divisions are located in Valley, Nebraska, except for wireless communication, which is located in Salem, Oregon. The principal operating locations of the Company are listed below. A map depicting 30 plants can be found on pages 8 and 9 in the Annual Report.

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ITEM 3. LEGAL PROCEEDINGS.

    The Company is not a party to, nor is any of its property subject to, any material legal proceedings. The Company is from time to time engaged in routine litigation incidental to the business.

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

    No matters were submitted to a vote of stockholders during the fourth quarter of 2000.

Executive Officers of the Company

    The executive officers of the Company at December 30, 2000, their ages, positions held, and the business experience of each during the past five years are, as follows:

    Mogens C. Bay, age 52, Chairman and Chief Executive Officer of the Company since January 1997. President and Chief Executive Officer of the Company from August 1993 to December 1996 and Director of the Company since October 1993.

    Terry J. McClain, age 53, Senior Vice President and Chief Financial Officer of the Company since January 1997. Previously Vice President and Chief Financial Officer of the Company from January 1994 until December 1996.

    E. Robert Meaney, age 53, Senior Vice President-International of the Company since September 1998. President and Chief Operating Officer-Valmont International from February 1994 to September 1998.

    Ann F. Ashford, age 40, Vice President-Human Resources of the Company since December 1999. Vice President-Human Resources, PKS Information Services, Inc., from January 1998 to December 1999. Director-Human Resources, MFS Communications Company, Inc., from January 1995 to September 1997.

    Jill A. Daily, age 54, Vice President-Procurement of the Company since June 1999. Manager-Global Procurement for Education and Development, Rohm and Haas Company, from June 1996 to June 1999. Manager-Global Procurement Training, Rohm and Haas Company, from November 1994 to June 1996.

    Thomas P. Egan, Jr., age 52, Vice President, Corporate Counsel and Secretary of the Company since 1984.

    Mark C. Jaksich, age 43, Vice President and Controller of the Company since February 2000. Director of Corporate Accounting of the Company from April 1998 to February 2000. Controller-Valmont International from July 1994 to April 1998.

    Mark E. Treinen, age 45, Vice President-Business Development since January 1994.

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PART II

ITEM 5. MARKET FOR THE REGISTRANT'S COMMON STOCK AND RELATED STOCKHOLDER MATTERS.

ITEM 6. SELECTED FINANCIAL DATA.

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

    The information called for by items 5, 6 and 7 is incorporated by reference to the following captioned paragraphs (at the pages indicated) in the Company's Annual Report:

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

    The information called for by item 7A is incorporated by reference to the captioned paragraph, "Risk Management", in the Company's Annual Report on Page 36.

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

    The financial statements called for by this item are incorporated by reference to the Company's Annual Report as set forth on pages 40 through 49, together with the independent auditors' report on page 51. The supplemental quarterly financial information is incorporated herein by reference to page 50 of the Company's Annual Report.

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE.

    None.

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PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT.

ITEM 11. EXECUTIVE COMPENSATION.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS.

    Except for the information relating to the executive officers of the Company set forth in Part I of this 10-K Report, the information called for by items 10, 11, 12 and 13 is incorporated by reference to the sections entitled "Certain Shareholders", "Election of Directors", "Summary Compensation Table", "Stock Option Grants in Fiscal Year 2000", "Options Exercised in Fiscal Year 2000 and Fiscal Year End Values", and "Long-Term Incentive Plans-Awards in Fiscal Year 2000" in the Company's Proxy Statement.

PART IV

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K.

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VALMONT INDUSTRIES, INC. AND SUBSIDIARIES

Index to Consolidated Financial Statements and Consolidated Financial Statement Schedule

Consolidated Financial Statements

The following consolidated financial statements of Valmont Industries, Inc. and subsidiaries have been incorporated by reference to pages 40 to 49 of the Company's Annual Report to Shareholders for the year ended December 30, 2000:

Independent Auditors' Report—Page 51 of the annual report.

Consolidated Balance Sheets—December 30, 2000 and December 25, 1999

Consolidated Statements of Operations—Three-Year Period Ended December 30, 2000

Consolidated Statements of Shareholders' Equity—Three-Year Period Ended December 30, 2000

Consolidated Statements of Cash Flows—Three-Year Period Ended December 30, 2000

Notes to Consolidated Financial Statements—Three-Year Period Ended December 30, 2000

All other schedules have been omitted as the required information is inapplicable or the information is included in the consolidated financial statements or related notes.

Separate financial statements of the registrant have been omitted because the registrant meets the requirements which permit omission.

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INDEPENDENT AUDITORS' REPORT ON FINANCIAL STATEMENT SCHEDULE

To the Board of Directors and Shareholders of Valmont Industries, Inc.

    We have audited the consolidated financial statements of Valmont Industries, Inc. and Subsidiaries (the Company) as of December 30, 2000 and December 25, 1999, and for each of the three years in the period ended December 30, 2000, and have issued our report thereon dated February 27, 2001; such financial statements and report are included in your 2000 Annual Report to Shareholders and are incorporated herein by reference. Our audits also included the financial statement schedule of the Company listed in Item 14 of this Form 10-K. This financial statement schedule is the responsibility of the Company's management. Our responsibility is to express an opinion based on our audits. In our opinion, such financial statement schedule, when considered in relation to the basic consolidated financial statements taken as a whole, presents fairly in all material respects the information set forth therein.

DELOITTE & TOUCHE LLP

Omaha, Nebraska
February 27, 2001

F-2

Schedule II

VALMONT INDUSTRIES, INC. AND SUBSIDIARIES
Valuation and Qualifying Accounts
(Dollars in thousands)

* The deductions from reserves are net of recoveries.

F-4

SIGNATURES

    Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized, on the 21st day of March, 2001.

    Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities indicated on the dates indicated.

    * Mogens C. Bay, by signing his name hereto, signs the Annual Report on behalf of each of the directors indicated on this 21st day of March, 2001. A Power of Attorney authorizing Mogens C. Bay to sign the Annual Report of Form 10-K on behalf of each of the indicated directors of Valmont Industries, Inc. has been filed herein as Exhibit 24.

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INDEX TO EXHIBITS

    Pursuant to Item 601(b)(4) of Regulation S-K, certain instruments with respect to the registrant's long-term debt are not filed with this Form 10-K. Valmont will furnish a copy of such long-term debt agreements to the Securities and Exchange Commission upon request.

    Except for those portions of Valmont Industries, Inc.'s Annual Report to Stockholders for its fiscal year ended December 30, 2000 (such portions filed hereto as Exhibit 13) specifically incorporated by reference in this report of Form 10-K, such annual report is furnished solely for the information of the Securities and Exchange Commission and is not deemed "filed" as part of this filing.

    Management contracts and compensatory plans are set forth as exhibits 10(i) through 10(v).

    * Filed herewith.

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