<PAGE>   1


                             SECURITIES AND EXCHANGE
                                   COMMISSION

                             Washington, D.C. 20549

                                   ----------

                                    FORM 10-Q

                   Quarterly Report Under Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                                   ----------


For Quarter Ended December 31, 2000                Commission File number 1-5341


                                ELCOR CORPORATION
             ------------------------------------------------------
             (Exact name of Registrant as specified in its charter)


<TABLE>
<S>                                                         <C>
         DELAWARE                                               75-1217920
---------------------------                                 ------------------
(State or other jurisdiction of                              (I.R.S. Employer
incorporation or organization)                              Identification No.)


          14643 DALLAS PARKWAY
SUITE 1000, WELLINGTON CENTRE, DALLAS, TEXAS                    75240-8871
--------------------------------------------                    ----------
  (Address of principal executive offices)                      (Zip Code)
</TABLE>

Registrant's telephone number, including area code           (972) 851-0500

         Indicate by check mark whether the Registrant (1) has filed all reports
required to be filed by Section 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    .
                                             ---     ---

         As of close of business on February 1, 2001, Registrant had outstanding
19,213,953 shares of Common Stock, Par Value $1 per Share.

<PAGE>   2

PART I.  FINANCIAL INFORMATION

ITEM 1.  Financial Statements

                                ELCOR CORPORATION
                           CONSOLIDATED BALANCE SHEET
                           (Unaudited, $ in thousands)

<TABLE>
<CAPTION>
                                                      December 31,   June 30,
ASSETS                                                   2000          2000
                                                      -----------   ---------
<S>                                                    <C>          <C>
CURRENT ASSETS
Cash and cash equivalents                              $   3,461    $   4,702
Trade receivables, less allowance of $958 and $963        48,429       71,712
Inventories -
         Finished goods                                   43,258       29,249
         Work-in-process                                     535          259
         Raw materials                                    14,411       11,457
                                                       ---------    ---------
                  Total inventories                       58,204       40,965
                                                       ---------    ---------

Prepaid expenses and other                                 4,127        4,312
Deferred income taxes                                      2,937        2,822
                                                       ---------    ---------
                  Total current assets                   117,158      124,513
                                                       ---------    ---------

PROPERTY, PLANT AND EQUIPMENT, AT COST                   304,851      279,028
         Less - accumulated depreciation                 (90,385)     (83,924)
                                                       ---------    ---------
                  Property, plant and equipment, net     214,466      195,104
                                                       ---------    ---------

OTHER ASSETS                                               2,797        2,957
                                                       ---------    ---------
                                                       $ 334,421    $ 322,574
                                                       =========    =========
LIABILITIES AND SHAREHOLDERS' EQUITY

CURRENT LIABILITIES
Accounts payable                                       $  33,824    $  36,034
Accrued liabilities                                        9,404       12,253
                                                       ---------    ---------
                  Total current liabilities               43,228       48,287
                                                       ---------    ---------

LONG-TERM DEBT                                           108,000       91,300
DEFERRED INCOME TAXES                                     22,474       21,083

SHAREHOLDERS' EQUITY -
         Common stock, $1 par                             19,988       19,988
         Paid-in-capital                                  58,155       58,480
         Retained earnings                                94,654       90,641
                                                       ---------    ---------
                                                         172,797      169,109

         Less --  Treasury stock (776,334 and
                    436,395 shares, at cost)             (12,078)      (7,205)
                                                       ---------    ---------
                  Total shareholders' equity             160,719      161,904
                                                       ---------    ---------
                                                       $ 334,421    $ 322,574
                                                       =========    =========
</TABLE>


See accompanying notes to consolidated financial statements.



                                       1
<PAGE>   3

                                ELCOR CORPORATION
                      CONSOLIDATED STATEMENT OF OPERATIONS
                           (Unaudited, $ in thousands
                             except per share data)

<TABLE>
<CAPTION>
                                                       Three Months Ended         Six Months Ended
                                                           December 31,             December 31,
                                                     ----------------------    ----------------------
                                                        2000        1999         2000          1999
                                                     ---------    ---------    ---------    ---------
<S>                                                  <C>          <C>          <C>          <C>
SALES                                                $  68,620    $  81,736    $ 154,821    $ 177,525
                                                     ---------    ---------    ---------    ---------

COST AND EXPENSES
       Cost of sales                                    53,825       60,674      120,244      130,416
       Selling, general and administrative              12,548        9,838       23,987       19,350
                                                     ---------    ---------    ---------    ---------
INCOME FROM OPERATIONS                                   2,247       11,224       10,590       27,759
                                                     ---------    ---------    ---------    ---------

OTHER INCOME (EXPENSE)
       Gain from involuntary conversion                     --          889           --          889
       Interest expense, net                              (623)        (104)      (1,128)        (521)
                                                     ---------    ---------    ---------    ---------

INCOME BEFORE INCOME TAXES                               1,624       12,009        9,462       28,127
       Provision for income taxes                          619        4,538        3,513       10,647
                                                     ---------    ---------    ---------    ---------
NET INCOME                                           $   1,005    $   7,471    $   5,949    $  17,480
                                                     =========    =========    =========    =========

NET INCOME PER SHARE-BASIC                           $     .05    $     .38    $     .31    $     .89
                                                     =========    =========    =========    =========

NET INCOME PER SHARE-DILUTED                         $     .05    $     .37    $     .30    $     .87
                                                     =========    =========    =========    =========

DIVIDENDS PER COMMON SHARE                           $     .05    $     .05    $     .10    $     .10
                                                     =========    =========    =========    =========
</TABLE>


See accompanying notes to consolidated financial statements.


                                       2
<PAGE>   4

                                ELCOR CORPORATION
                      CONSOLIDATED STATEMENT OF CASH FLOWS
                           (Unaudited, $ in thousands)

<TABLE>
<CAPTION>
                                                                                 Six Months Ended
                                                                                   December 31,
                                                                              --------------------
                                                                                2000        1999
                                                                              --------    --------
<S>                                                                           <C>         <C>
CASH FLOWS FROM OPERATING ACTIVITIES

         Net income                                                           $  5,949    $ 17,480
         Adjustments to reconcile net income
            to net cash provided by operating activities:

                  Depreciation and amortization                                  6,699       5,254
                  Deferred income taxes                                          1,276         401
                  Gain from involuntary conversion                                  --        (889)
                  Changes in assets and liabilities:
                     Trade receivables                                          23,283      21,607
                     Inventories                                               (17,239)     (9,257)
                     Prepaid expenses and other                                    185       2,672
                     Accounts payable and accrued liabilities                   (5,059)      6,987
                                                                              --------    --------

                  Net cash provided by operating activities                     15,094      44,255
                                                                              --------    --------

CASH FLOWS FROM INVESTING ACTIVITIES

         Additions to property, plant and equipment                            (26,048)    (31,330)
         Insurance proceeds from involuntary conversion                             --       1,651
         Other                                                                     147         (72)
                                                                              --------    --------

                  Net cash used for investing activities                       (25,901)    (29,751)
                                                                              --------    --------

CASH FLOWS FROM FINANCING ACTIVITIES

         Long-term borrowings, net                                              16,700     (13,700)
         Dividends on common stock                                              (1,936)     (1,956)
         Treasury stock transactions and other, net                             (5,198)        236
                                                                              --------    --------

                  Net cash provided by (used for) financing activities           9,566     (15,420)
                                                                              --------    --------

NET DECREASE IN CASH AND CASH EQUIVALENTS                                       (1,241)       (916)

CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR                                   4,702       4,186
                                                                              --------    --------

CASH AND CASH EQUIVALENTS AT END OF PERIOD                                    $  3,461    $  3,270
                                                                              ========    ========
</TABLE>


See accompanying notes to consolidated financial statements.


                                       3
<PAGE>   5

                                ELCOR CORPORATION
                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                   (Unaudited)

1.       The attached condensed consolidated financial statements have been
         prepared pursuant to the rules and regulations of the Securities and
         Exchange Commission. As a result, certain information and footnote
         disclosures normally included in financial statements prepared in
         accordance with generally accepted accounting principles have been
         condensed or omitted. The company believes that the disclosures
         included herein are adequate to make the information presented not
         misleading. These condensed consolidated financial statements should be
         read in conjunction with the consolidated financial statements and
         related notes included in the company's fiscal 2000 Annual Report on
         Form 10-K. The unaudited financial information contained herein has
         been prepared in conformity with generally accepted accounting
         principles on a consistent basis and does reflect all adjustments which
         are, in the opinion of management, necessary for a fair presentation of
         the results of operations for the three-month and six-month periods
         ending December 31, 2000 and 1999, but are, however, subject to
         year-end audit by the company's independent auditors. Because of
         seasonal, weather-related conditions in some of the company's market
         areas, sales can vary at times, and results of any one quarter or other
         interim reporting period should not necessarily be considered as
         indicative of results for a full fiscal year.

2.       In accordance with the requirements of FASB SFAS No. 131, the company
         is segregated into the following segments: Roofing Products,
         Electronics Manufacturing Services and Industrial Products. The Roofing
         Products segment consists of the various operating subsidiaries of Elk
         Corporation of Dallas (collectively Elk). These companies manufacture
         and sell premium laminated fiberglass asphalt residential and accessory
         roofing products, together with nonwoven mats used in manufacturing
         asphalt roofing products and various industrial applications.

         The Electronics Manufacturing Services segment consists of the various
         operating subsidiaries of Cybershield, Inc. (collectively Cybershield).
         These companies are engaged in the shielding of plastic electronics
         enclosures by the use of electroless metallic chemicals, vacuum
         metalization, robotic spray metallic paints and conductive dispense
         gaskets, application of pad print and/or decorative paint finishes,
         installation of antenna components, light tubes, battery connections,
         inserts, subassembly operations and other value added services for the
         telecommunications, computer and electronic equipment industries. Due
         to the increasing materiality of the Electronics Manufacturing Services
         business to the company, its operations have been segregated into a
         separate segment as of June 30, 2000. These operations were previously
         included in the Industrial Products segment.

         The Industrial Products segment is comprised of: (1) surface finishing
         of original equipment and remanufactured reciprocating diesel engine
         components used in the railroad and marine transportation industries;
         and (2) technology licensing and consulting services for the natural
         gas processing industry.


                                       4
<PAGE>   6

       Financial information by company segment is summarized as follows
       (in thousands):

<TABLE>
<CAPTION>
                                        Three Months Ended        Six Months Ended
                                           December 31,             December 31,
                                     ----------------------    ----------------------
                                       2000         1999         2000         1999
                                     ---------    ---------    ---------    ---------
<S>                                  <C>          <C>          <C>          <C>
SALES
Roofing products                     $  56,623    $  68,830    $ 131,841    $ 151,769
Electronics manufacturing services       8,347        9,865       16,736       19,009
Industrial products                      3,621        2,996        6,185        6,658
Corporate and eliminations                  29           45           59           89
                                     ---------    ---------    ---------    ---------
                                     $  68,620    $  81,736    $ 154,821    $ 177,525
                                     =========    =========    =========    =========
OPERATING PROFIT
Roofing products                     $   3,363    $  11,318    $  14,362    $  27,595
Electronics manufacturing services         919        2,252        1,616        3,612
Industrial products                        297         (845)        (948)        (676)
Corporate and other                     (2,332)      (1,501)      (4,440)      (2,772)
                                     ---------    ---------    ---------    ---------
                                         2,247       11,224       10,590       27,759
Gain from involuntary conversion            --          889           --          889
Interest expense, net                     (623)        (104)      (1,128)        (521)
                                     ---------    ---------    ---------    ---------
Income before income taxes           $   1,624    $  12,009    $   9,462    $  28,127
                                     =========    =========    =========    =========

IDENTIFIABLE ASSETS
Roofing products                     $ 273,872    $ 212,863    $ 273,872    $ 212,863
Electronics manufacturing services      31,303       24,096       31,303       24,096
Industrial products                      9,742        7,524        9,742        7,524
Corporate                               19,504       17,449       19,504       17,449
                                     ---------    ---------    ---------    ---------
                                     $ 334,421    $ 261,932    $ 334,421    $ 261,932
                                     =========    =========    =========    =========
DEPRECIATION AND AMORTIZATION
Roofing products                     $   2,203    $   2,110    $   4,396    $   4,211
Electronics manufacturing services         330          413          790          790
Industrial products                         65           86          150          177
Corporate                                  682           38        1,363           76
                                     ---------    ---------    ---------    ---------
                                     $   3,280    $   2,647    $   6,699    $   5,254
                                     =========    =========    =========    =========
CAPITAL EXPENDITURES
Roofing products                     $   8,490    $  16,130    $  22,232    $  25,372
Electronics manufacturing services       1,109          912        3,339        2,815
Industrial products                        118          544          370          564
Corporate                                   33        1,134          107        2,579
                                     ---------    ---------    ---------    ---------
                                     $   9,750    $  18,720    $  26,048    $  31,330
                                     =========    =========    =========    =========
</TABLE>


                                       5
<PAGE>   7

3.       Basic earnings per share is computed based on the average number of
         common shares outstanding. Diluted earnings per share includes
         outstanding stock options. The following table sets forth the
         computation of basic and diluted earnings per share (dollars and share
         totals, in thousands):

<TABLE>
<CAPTION>
                                        Three Months Ended   Six Months Ended
                                            December 31,       December 31,
                                        ------------------  -----------------
                                          2000      1999      2000      1999
                                        -------   -------   -------   -------
<S>                                     <C>       <C>       <C>       <C>
Net income                              $ 1,005   $ 7,471   $ 5,949   $17,480
                                        =======   =======   =======   =======

Denominator for basic earnings
per share - weighted average
shares outstanding                       19,317    19,564    19,420    19,546

Effect of dilutive securities:
Employee stock options                      121       507       177       481
                                        -------   -------   -------   -------

Denominator for dilutive earnings per
share - adjusted weighted average
shares and assumed issuance of shares
purchased under incentive stock
option plan using the treasury
stock method                             19,438    20,071    19,597    20,027
                                        =======   =======   =======   =======

Basic earnings per share                $   .05   $   .38   $   .31   $   .89
                                        =======   =======   =======   =======

Diluted earnings per share              $   .05   $   .37   $   .30   $   .87
                                        =======   =======   =======   =======
</TABLE>

4.       On November 30, 2000, the company increased its unsecured revolving
         credit facility from $125,000,000 to $175,000,000 and extended its term
         to November 30, 2005. The pricing level for prime rate loans,
         Eurodollar rate loans and commitment fees were increased and are based
         on the company's leverage ratio, as defined, at each quarter end. Based
         on the leverage ratio at December 31, 2000, the Eurodollar borrowing
         rate was LIBOR plus 1.125% and the commitment fee was .25% of the
         average unused portion of the line.

         The facility, among other things, requires that the company maintain a
         specified minimum consolidated net worth, a minimum interest coverage
         ratio and a maximum capitalization ratio, all based on defined terms.
         The facility also contains restrictions that limit the payment of cash
         dividends and stock repurchases based on defined criteria.

5.       During the second quarter of fiscal 2001, management determined that
         the useful lives of certain buildings and equipment utilized in the
         Electronics Manufacturing Services segment were longer than originally
         established. A change in accounting estimate was recognized to reflect
         this decision, resulting in an increase in pretax income of $150,000
         per fiscal quarter beginning in the quarter ended December 31, 2000.


                                        6
<PAGE>   8

ITEM 2. Management's Discussion and Analysis of Financial Condition and Results
of Operations

RESULTS OF OPERATIONS

CHANGES IN THE THREE-MONTH PERIOD ENDED DECEMBER 31, 2000 COMPARED TO THE
THREE-MONTH PERIOD ENDED DECEMBER 31, 1999.

     During the three-month period ended December 31, 2000, net income decreased
87% to $1,005,000 compared to $7,471,000 for the same prior year period. Sales
decreased 16% to $68,620,000 in the second quarter of fiscal 2001 compared to
$81,736,000 in the same period of fiscal 2000. Decreased sales and income were
reported in the Roofing Products and Electronics Manufacturing Services
segments. However, the Industrial Products segment achieved higher sales and
much improved operating results. During the three-month period ended December
31, 1999, the company recorded $889,000 gain from involuntary conversion as a
result of insurance proceeds exceeding the book value of assets destroyed in a
plant explosion in September 1998 at its nonwoven fiberglass roofing mat plant
in Ennis, Texas. Final settlement with the company's insurance company was
reached in fiscal 2000.

     Sales for the Roofing Products segment decreased 18% to $56,623,000 for the
three months ended December 31, 2000 compared to $68,830,000 in the same prior
year quarter. The decrease in sales reflected a decline in shipments of both
laminated asphalt shingles and nonwoven fiberglass roofing mat sold to other
roofing manufacturers. Lower demand for residential asphalt roofing products in
many regions of the country resulting from weakening industry conditions was
exacerbated by unusually harsh weather conditions in some areas of the United
States in the current year quarter, as compared to prior year record demand
levels.

     Operating income for the Roofing Products segment decreased 70% to
$3,363,000 for the three months ended December 31, 2000 compared to $11,318,000
in the prior year quarter. The decrease in operating income compared to the
prior year is primarily the result of the decrease in shipments of premium
laminated fiberglass shingles and nonwoven fiberglass mats, combined with
significantly higher costs for raw materials and higher expenses relating to the
start-up of new facilities and products. While asphalt costs have remained
relatively stable in fiscal 2001, the price of asphalt, which accounts for about
24% of cost of goods sold for laminated asphalt shingles, increased 32% in the
quarter ended December 31, 2000 compared to the same quarter last year. Average
selling prices for laminated shingles were about flat in the current year
quarter compared to the same prior year period.

     Sales for the Electronics Manufacturing Services segment decreased 15% to
$8,347,000 in the second quarter of fiscal 2001 compared to $9,865,000 in the
same period last year. Prior year quarter sales benefited from higher production
levels of components for more mature digital cell phone models. Operating income
decreased 59% to $919,000 in the three-month period ended December 31, 2000 from
$2,252,000 in the same three-month period last year. The current year's second
quarter results reflect lower production volumes of these mature phone
components and higher costs associated with ramping up production of components
for several new phone models.

     Sales for the Industrial Products Group increased 21% to $3,621,000 in the
three-month period ending December 31, 2000 compared to $2,996,000 in the same
prior year quarter. A $297,000 operating profit was reported in the current year
quarter compared to an $845,000 operating loss in the prior year quarter.
Significantly improved results were due primarily to Chromium Corporation's
turnaround after consolidating all manufacturing operations into its Cleveland,
Ohio facility. The prior


                                        7
<PAGE>   9


year operating loss included about $800,000 of nonrecurring costs to relocate
equipment and other consolidation related items. Ortloff Engineers, the
company's patent licensing and engineering consulting services business, also
reported improved operating results in the current year quarter compared to the
same prior year quarter.

     Overall selling, general and administrative costs (SG&A) in the three-month
period ending December 31, 2000 were significantly higher than in the same
period in the prior fiscal year. Increased costs compared to the prior year
period included higher sales and marketing costs in the Roofing Products segment
and higher depreciation at corporate relating to the new enterprise resource
system.

     Net interest expense in the second quarter of fiscal 2001 was $623,000
compared to $104,000 in the same prior year period. The company capitalized
$1,419,000 of interest in the current year quarter compared to $509,000 in the
prior year quarter. Capitalized interest expense in both years related to the
construction of the new Myerstown, Pennsylvania shingle plant and other major
projects.

CHANGES IN THE SIX-MONTH PERIOD ENDED DECEMBER 31, 2000 COMPARED TO THE
SIX-MONTH PERIOD ENDED DECEMBER 31, 1999.

     During the six-month period ended December 31, 2000, net income decreased
to $5,949,000 from $17,480,000 in last year's first half. Sales decreased 13% to
$154,821,000 in the current year period from $177,525,000 in the same prior year
period. Decreased sales and income were reported in the Roofing Products and
Electronics Manufacturing Services segments. The Industrial Products segment
reported a small reduction in sales and a slightly higher operating loss for the
first half of fiscal 2001 compared to the same prior year period.

     Sales for the Roofing Products segment decreased 13% to $131,841,000 for
the six months ended December 31, 2000 compared to $151,769,000 in the same
period last year. During the first half of fiscal 2001, sales of the company's
laminated asphalt shingles and nonwoven fiberglass mat sold to other roofing
manufacturers declined in many regions of the country, particularly in the
Western United States, as a result of a combination of factors, including
overall weakened economic conditions, unusually harsh winter weather conditions
and actions by competitors to increase their production of laminated shingles to
compensate for lower demand for commodity shingles.

     Operating income for the Roofing Products segment decreased significantly
to $14,362,000 for the first six months of fiscal 2001 compared to $27,595,000
for the same period in the prior fiscal year. Although average selling prices
for laminated shingles were slightly higher in the current year period compared
to the same period last year, the increased sales prices did not offset the
significantly higher costs for raw materials, particularly asphalt costs, and
higher expenses relating to start-up of the new Myerstown, Pennsylvania roofing
plant and development of new products. These factors, combined with lower
shipments of roofing products, resulted in a 48% reduction in operating profit
compared to the prior year.

     Management is cautiously optimistic that recent heavy rains in the Western
United States and harsh winter weather conditions in the Midwestern and Northern
regions of the United States may provide the impetus for increased demand in the
months ahead. Further, recent actions of competitors to close inefficient
roofing plants and to curtail production at selected roofing plants may reduce
industry wide excess inventories which have restricted the industry's ability to
recover sharply higher raw material and transportation costs through increased
pricing.


                                        8
<PAGE>   10

     Sales for the Electronics Manufacturing Services segment decreased 12% to
$16,736,000 in the six-month period ended December 31, 2000 compared to
$19,009,000 in the same period in the prior fiscal year. Lower sales were
primarily the result of reduced demand for mature digital cell phone models
served by Cybershield as new models are being introduced into the market.
Operating income decreased 55% to $1,616,000 in the first half of fiscal 2001
from $3,612,000 in the six-month period ended December 31, 1999. Decreased
operating income is primarily attributable to reduced sales and higher costs
during initial production ramp-ups on new digital wireless handset products.

     Sales and operating profit for the Electronics Manufacturing Services
segment are expected to increase in the third and fourth quarters of fiscal 2001
due to the scheduled ramp-up of new cellular handset components and other new
products. Although there are many uncertainties in the market, if Cybershield's
telecom customers maintain current production schedules, full year fiscal 2001
sales and operating income could exceed fiscal 2000 results by about a third.

     Sales for the Industrial Products segment decreased 7% in the six-month
period ended December 31, 2000 to $6,185,000 from $6,658,000 for the same period
in the prior fiscal year. A $948,000 operating loss was reported in the current
year period compared to a $676,000 operating loss in the prior year period.
However, the current year operating loss occurred in July 2000 and was the
result of the consolidation of manufacturing operations and initial production
of products new to Chromium Corporation's Cleveland, Ohio plant. Excluding the
results for July 2000, Chromium has generated an operating profit for the
current year period and the outlook appears good for continuing improvement as
fiscal 2001 progresses. The prior year period operating loss included a
significant amount of nonrecurring items relating to the consolidation of
Chromium's manufacturing operations. Excluding these costs, Chromium's operating
results were near break-even in the first six-months of fiscal 2000. Ortloff
Engineers experienced lower sales and operating results in the first half of
fiscal 2001 compared to the same prior year period. However, its outlook for
awards of significant licenses of the company's leading edge patented cryogenic
gas processing technology appears good for the remainder of fiscal 2001.

     Overall S,G&A costs in the six-month period ending December 31, 2000 were
significantly higher than in the same period in the prior fiscal year, primarily
as a result of higher sales and marketing costs in the Roofing Products segment
and higher depreciation at corporate relating to its new enterprise resource
system.

     Net interest expense in the first half of fiscal 2001 was $1,128,000
compared to $521,000 in the same prior year period. The company capitalized
$2,667,000 of interest in the current year period compared to $784,000 of
interest in the prior year period in connection with the construction of its new
Myerstown, Pennsylvania shingle plant and other major products. Interest expense
is expected to be higher in the second half of fiscal 2001, primarily due to
higher borrowing rates and increased debt levels relating to the seasonal
increases in working capital requirements.

FINANCIAL CONDITION

     During the first six months of fiscal 2001, the company generated cash
flows of $15,094,000. Overall working capital at December 31, 2000 (excluding
cash and cash equivalents) was $1,055,000 lower than at June 30, 2000. Trade
receivables were $23,283,000 lower at December 31, 2000 compared to June 30,
2000, primarily due to seasonality in the roofing business. However, the
decrease in receivables was almost totally offset by higher inventories and
lower current liabilities.


                                       9
<PAGE>   11


     Higher inventories of premium laminated fiberglass shingles and roofing
mats reflect increases in both units and cost per unit basis, as well as
building an initial base level of inventory at the new Myerstown, Pennsylvania
roofing plant. Although inventories are higher than planned due to lower
shipments of residential asphalt roofing products in the December 2000 quarter,
management does not believe the current level of inventory to be excessive.
Inventory levels are being closely monitored in relation to current and
projected sales levels. The current ratio at December 31, 2000 was 2.7:1
compared to 2.6:1 at the end of fiscal 2000. Historically, working capital
requirements fluctuate during the year because of seasonality in some market
areas. Generally, working capital requirements and related borrowings are higher
in the spring and summer months, and lower in the fall and winter months.

     The company used $25,901,000 for net investing activities in the first six
months of fiscal 2001. Most expenditures were for additions to property, plant
and equipment. About $19,100,000 of capital expenditures in the first six months
of fiscal 2001 were for construction costs relating to the new Myerstown,
Pennsylvania premium laminated fiberglass asphalt shingle plant. Construction of
this new facility has been completed, start-up is underway and progressing very
smoothly and limited manufacturing operations began in the December 2000
quarter. The Myerstown plant is expected to increase the company's overall
laminated shingle capacity by about 38%. The company plans to continue its
expansion plan over the next several years in accordance with its assessment of
growth in market demand, primarily by expanding capacity and improving
productivity at existing plants, developing new products, installing production
lines for new products, and increasing capacity for Cybershield's digital
wireless cellular phone business, including international expansion.

     Cash flows from financing activities were $9,566,000 during the first half
of fiscal 2001, primarily resulting from a $16,700,000 increase in long-term
debt. Long-term debt represented 40% of the $268,719,000 of invested capital
(long-term debt plus shareholders' equity) at December 31, 2000.

     In September 1998, the company's Board of Directors authorized the purchase
of up to $10,000,000 of common shares from time to time on the open market to be
used for general corporate purposes. On August 28, 2000, the Board of Directors
authorized the repurchase of up to an additional $10,000,000 of common stock. As
of December 31, 2000, 600,590 shares with cumulative cost of $9,366,000 had been
repurchased under these authorizations.

     On November 30, 2000, the company increased its revolving credit facility
from $125,000,000 to $175,000,000 to support its capital expansion program.
Management believes that current cash and cash equivalents, projected cash flows
from operations and the increased unsecured revolving credit facility should be
sufficient during fiscal 2001 and beyond to fund its expansion plans, working
capital needs, dividends, stock repurchases and other cash requirements.

     The company's operations are subject to extensive federal, state and local
laws and regulations relating to environmental matters. Although the company
does not believe it will be required to expend amounts which will have a
material adverse effect on the company's consolidated financial position or
results of operations by reason of environmental laws and regulations, such laws
and regulations are frequently changed and could result in significantly
increased cost of compliance. Further, certain of the company's industrial
products and electronics manufacturing services operations utilize hazardous


                                       10
<PAGE>   12

materials in their production processes. As a result, the company incurs costs
for remediation activities off-site and at its facilities from time to time. The
company establishes and maintains reserves for such remediation activities, when
appropriate. Current reserves established for known or probable remediation
activities are not material to the company's financial position or results of
operations.

FORWARD-LOOKING STATEMENTS

         In an effort to give investors a well-rounded view of the company's
current condition and future opportunities, management's discussion and analysis
of the results of operations and financial condition and other sections of this
Form 10-Q contain "forward-looking statements" about its prospects for the
future. The statements that are not historical facts are "forward-looking
statements" within the meaning of the Private Securities Litigation Reform Act
of 1995. These statements usually are accompanied by words such as "outlook,"
"believe," "estimate," "plan," "project," "expect," "anticipate," "predict,"
"could," "should," "may," or similar words that convey the uncertainty of future
events or outcomes. These statements are based on judgments the company believes
are reasonable; however, the company's actual results could differ materially
from those discussed here. Such risks and uncertainties include, but are not
limited to, the following:

         1.       The company's roofing products business is substantially
                  non-cyclical, but can be affected by weather, the availability
                  of financing and general economic conditions. In addition, the
                  asphalt roofing products manufacturing business is highly
                  competitive. Actions of competitors, including changes in
                  pricing, or slowing demand for asphalt roofing products due to
                  general or industry economic conditions or the amount of
                  inclement weather could result in decreased demand for the
                  company's products, lower prices received or reduced
                  utilization of plant facilities. Further, changes in building
                  codes and other standards from time to time can cause changes
                  in demand, or increases in costs that may not be passed
                  through to customers.

         2.       In the asphalt roofing products business, the significant raw
                  materials are ceramic-coated granules, asphalt, glass fibers,
                  resins and mineral filler. Increased costs of raw materials
                  can result in reduced margins, as can higher trucking and rail
                  costs. Historically, the company has been able to pass some of
                  the higher raw material and transportation costs through to
                  the customer. Should the company be unable to recover higher
                  raw material and/or transportation costs from price increases
                  of its products, operating results could be adversely affected
                  and/or lower than projected.

         3.       The company has completed construction and is in process of
                  starting up its new roofing plant in Myerstown, Pennsylvania.
                  Progress in achieving anticipated operating efficiencies and
                  financial results is difficult to predict for new facilities.
                  If such progress is slower than anticipated or if demand for
                  products produced at the new facilities does not meet current
                  expectations, operating results could be adversely affected.


                                       11
<PAGE>   13


         4.       Certain facilities of the company's electronics manufacturing
                  services and industrial products subsidiaries must utilize
                  hazardous materials in their production process. As a result,
                  the company could incur costs for remediation activities at
                  its facilities or off-site, and other related exposures from
                  time to time in excess of established reserves for such
                  activities.

         5.       The company's litigation, including Elk's defense of purported
                  class action lawsuits, is subject to inherent and
                  case-specific uncertainty. The outcome of such litigation
                  depends on numerous interrelated factors, many of which cannot
                  be predicted.

         6.       Although the company currently anticipates that most of its
                  needs for new capital in the near future will be met with
                  internally generated funds or borrowings under its available
                  credit facilities, significant increases in interest rates
                  could substantially affect its borrowing costs under its
                  existing loan facility, or its cost of alternative sources of
                  capital.

         7.       Each of the company's businesses, especially Cybershield's
                  shielding business, is subject to the risks of technological
                  changes that could affect the demand for or the relative cost
                  of the company's products and services, or the method and
                  profitability of the method of distribution or delivery of
                  such products and services. In addition, the company's
                  businesses each could suffer significant setbacks in revenues
                  and operating income if it lost one or more of its largest
                  customers, or if its customers' plans and/or markets should
                  change significantly.

         8.       Although the company insures itself against physical loss to
                  its manufacturing facilities, including business interruption
                  losses, natural or other disasters and accidents, including
                  but not limited to fire, earthquake, damaging winds and
                  explosions, operating results could be adversely affected if
                  any of its manufacturing facilities became inoperable for an
                  extended period of time due to such events.

         9.       Each of the company's businesses is actively involved in the
                  development of new products, processes and services which are
                  expected to contribute to the company's ongoing long-term
                  growth and earnings. If such development activities are not
                  successful, or the company cannot provide the requisite
                  financial and other resources to successfully commercialize
                  such developments, the growth of future sales and earnings may
                  be adversely affected.

         Parties are cautioned not to rely on any such forward-looking beliefs
or judgments in making investment decisions.


                                       12
<PAGE>   14

PART II.  OTHER INFORMATION

ITEM 4:  Submission of Matters to a Vote of Security Holders

     (a)  The company's Annual Meeting of Shareholders was held on October 24,
          2000 for the purpose of electing two directors and ratifying the
          appointment of the company's independent auditors.

     (b)  Directors Elected:

<TABLE>
<CAPTION>
                                                                                       NUMBER OF VOTES
                                                                                       ---------------
                                                                                 FOR                     AGAINST
                                                                                 ---                     -------
<S>                                                                           <C>                        <C>
                 Thomas D. Karol                                              17,911,495                     415
                 Dale V. Kesler                                               17,835,794                  76,116

                 Other Directors Whose Term Continued After the Meeting:

                 James E. Hall
                 Harold K. Work
                 David W. Quinn
                 Richard J. Rosebery
</TABLE>

     (c)  Other matters voted upon at the meeting and the number of affirmative
          votes, negative votes and abstentions.

<TABLE>
<CAPTION>
                                                                                      NUMBER OF VOTES
                                                           -----------------------------------------------------------
                                                           AFFIRMATIVE                 AGAINST             ABSTENTIONS
                                                           -----------                 -------             -----------
<S>                                                        <C>                        <C>                  <C>
                 Ratification of Arthur
                 Andersen LLP as
                 Independent auditors of
                 the company for the fiscal
                 year ending June 30, 2001                    17,971,779               50,332                  24,437
</TABLE>

ITEM 5:  Other Information

          On February 6, 2001, the company announced that the Board of Directors
          elected Thomas D. Karol, a member of the Board, as President and Chief
          Executive Officer, to succeed Harold K. Work, effective March 26,
          2001. Mr. Work will continue as Chairman of the Board of Directors for
          a transition period before retiring.

ITEM 6:  Exhibits and Reports on Form 8-K

     (a)  Exhibits:

          Exhibit (4.12): Credit Agreement dated as of November 30, 2000 among
          Elcor Corporation, Bank of America, N.A., as Administrative Agent,
          Swing Line Lender and L/C Issuer, Bank One, Texas, N.A., as
          Documentation Agent, First Union National Bank, as Syndication Agent,
          The Other Lenders Party Hereto, and Bank of America Securities LLC, as
          Sole Lead Arranger and Sole Book Manager.



                                       13
<PAGE>   15

       (b)       The registrant filed one report on Form 8-K during the quarter
                 ended December 31, 2000. The registrant filed a Form 8-K on
                 October 17, 2000 relating to a press release containing
                 "forward-looking statements" about its prospects for the future
                 and certain other information concerning the company's
                 disclosures under Regulation F-D.


                                       14
<PAGE>   16



                                   SIGNATURES




Pursuant to the requirements of the Securities and Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



                                         ELCOR CORPORATION



DATE:  February 13, 2001                 /s/ Richard J. Rosebery
                                         ---------------------------------
                                         Richard J. Rosebery
                                         Vice Chairman, Chief Financial &
                                         Administrative Officer

                                         /s/ Leonard R. Harral
                                         ---------------------------------
                                         Leonard R. Harral
                                         Vice President and Chief
                                         Accounting Officer



<PAGE>   17
                               INDEX TO EXHIBITS

<TABLE>
<CAPTION>
EXHIBIT
NUMBER                        DESCRIPTION
--------                      -----------
<S>                 <C>
 4.12               Credit Agreement dated as of November 30, 2000 among Elcor
                    Corporation, Bank of America, N.A., as Administrative Agent,
                    Swing Line Lender and L/C Issuer, Bank One, Texas, N.A., as
                    Documentation Agent, First Union National Bank, as
                    Syndication Agent, The Other Lenders Party Hereto, and Bank
                    of America Securities LLC, as Sole Lead Arranger and Sole
                    Book Manager.
</TABLE>