ARTICLES OF INCORPORATION
                                       of
                         CARDINAL FINANCIAL CORPORATION
 
         The undersigned does hereby establish a stock corporation under and by
virtue of the provisions of the Virginia Stock Corporation Act, Chapter 9, Title
13.1, of the 1950 Code of Virginia and acts amendatory thereof, for the purposes
and under the corporate name hereinafter mentioned, and to that end, does, by
these Articles of Incorporation, set forth the following:
 
                                    ARTICLE I
 
The name of the Corporation is Cardinal Financial Corporation.
                                   ARTICLE II
 
         The nature of the business and the purposes to be conducted and
promoted by the Corporation, that shall be in addition to the authority of the
Corporation to engage in any lawful act or activity for which corporations may
be organized under the Virginia Stock Corporation Act and acts amendatory
thereof, are to buy or otherwise acquire, own, manage, and sell, or otherwise
dispose of shares of capital stock and other securities of banks and other
corporations. In addition, the Corporation shall have the power to transact,
promote or carry on any business of any character that is not prohibited by law
or required to be stated in the articles.
 
         The foregoing provisions of this Article II shall be construed both as
purposes and powers and each as an independent purpose and power. The foregoing
enumeration of specific purposes and powers shall not be held to limit or
restrict in any manner the purposes and powers of the Corporation, and the
purposes and powers herein specified shall, except when otherwise provided in
this Article, be in no wise limited or restricted by reference to, or inference
from, the terms of any provision of this or any other Article in these articles
of incorporation; provided that the Corporation shall not conduct any business,
promote any purpose, or exercise any power or privilege within the Commonwealth
of Virginia that, under the laws thereof, the Corporation may not lawfully
conduct, promote or exercise.
 
                                   ARTICLE III
 
         The address of the registered office of the Corporation shall be 11350
Random Hills Road, Fifth Floor, Post Office Box 460, in the County of Fairfax,
Virginia 22030, and the name of the initial registered agent for the Corporation
shall be John H. Rust, Jr., a member of the Virginia State Bar and a resident of
Virginia, and whose address is 11350 Random Hills Road, Fifth Floor, Post Office
Box 460, Fairfax, Virginia 22030.
 
                                   ARTICLE IV
 
         The Corporation shall have authority to issue 50,000,000 shares of
common stock of $1.00 par value per share and 10,000,000 shares of preferred
stock of $1.00 par value per share.
 
                                       -1-
 
<PAGE>
 
         Common Stock. The holders of common stock shall, to the exclusion of
the holders of any other class of stock of the Corporation, have the sole and
full power to vote for the election of directors and for all other purposes
without limitation except only (i) as otherwise provided in the certificate of
serial designation for a particular series of preferred stock, and (ii) as
otherwise expressly provided by the then existing statutes of the Commonwealth
of Virginia. The holders of common stock shall have one vote for each share of
common stock held by them.
 
         Subject to the provisions of the certificate of serial designation for
series of preferred stock, the holders of common stock shall be entitled to
receive dividends, if, when and as declared therefor and to the net assets
remaining after payment of all liabilities upon voluntary or involuntary
liquidation of the Corporation.
 
         Preferred Stock. Authority is expressly vested in the Board of
Directors to divide the preferred stock into series and, within the following,
limitations, to fix and determine the relative rights and preferences of the
shares of any series so established and to provide for the issuance thereof.
Each series shall be so designated as to distinguish the shares thereof from the
shares of all other series and classes. All shares of preferred stock shall be
identical except as to the following, relative rights and preferences, as to
which there may be variations between different series:
 
         (a)   The rate of dividend, the time of payment and the dates from
which dividends shall be cumulative, and the extent of participation rights, if
any.
 
         (b)   Any right to vote with the holders of shares of any other series
or class and any right to vote as a class, either generally or as a condition to
specified corporate action.
 
         (c)   The price at and the terms and conditions on which shares may be
redeemed.
 
         (d)   The amount payable upon shares in event of involuntary
liquidation.
 
         (e)   The amount payable upon shares in event of voluntary liquidation.
 
         (f)   Sinking fund provisions for the redemption or purchase of shares.
 
         (g)   The terms and conditions on which shares may be converted, if the
shares of any series are issued with the privilege of conversion. Prior to the
issuance of any shares of a series of preferred stock, the Board of Directors
shall establish such series by adopting a resolution setting forth the
designation and number of shares of the series and the relative rights and
preferences thereof to the extent that the variations are permitted by the
provisions hereof.
 
         All series of preferred stock shall rank on a parity as to dividends
and assets with all other series according to the respective dividend rates and
amounts distributable upon any voluntary or involuntary liquidation of the
 
                                       -2-
 
<PAGE>
 
Corporation fixed for each such series and without preference or priority of any
series over any other series; but all shares of the preferred stock shall be
preferred over the common stock as to both dividends and amounts distributable
upon any voluntary or involuntary liquidation of the Corporation. All shares of
any one series shall be identical.
 
         Preemptive Rights. No holder of shares of the stock of any class of the
Corporation shall have any preemptive or preferential right to subscribe to or
purchase (i) any shares of any class of the stock of the Corporation, whether
now or hereafter authorized; or (ii) any securities or obligations of the
Corporation convertible into stock of the Corporation, issued or sold; or (iii)
any options, warrants or rights to purchase such shares or securities
convertible into any such shares.
 
         Rights, Options or Warrants. Authority is expressly vested in the Board
of Directors to create and issue rights, options, or warrants for the purchase
of shares of any class of the stock of the Corporation, upon such terms and
conditions and for such consideration, if any, and such purposes as the Board of
Directors may approve, without the necessity of shareholder approval.
 
                                    ARTICLE V
 
         The number of directors shall be fixed by the Bylaws, or, in the
absence of a Bylaw fixing the number, the number shall be nine. The directors
shall be divided into three classes (A, B, and C) as nearly equal in number as
possible. The initial term of office for members of Class A shall expire at the
first annual meeting of stockholders after their election; the initial term of
office for members of Class B shall expire at the second annual meeting of
stockholders after their election; and the initial term of office for members of
Class C shall expire at the third annual meeting of stockholders after their
election. At each annual meeting of stockholders following such initial
classification and election, directors elected to succeed those directors whose
terms expire shall be elected for a term of office to expire at the third
succeeding annual meeting of stockholders after their election, and shall
continue to hold office until their respective successors are elected and
qualify.
 
         The initial Board of Directors of the Corporation shall consist of nine
persons, and the names and addresses of the persons who are to serve as the
Directors of the Corporation and the class to which each director is assigned
are as follows:
 
<TABLE>
<S>                          <C>                                <C>
Class A Directors            Class B Directors                   Class C Directors Wayne W. Broadwater
Nancy K. Falck               Robert M. Barlow 12031 Wright Lane                   1502 Basswood Court
9411 Piscataway Lane Bristow, VA 20136-1613       McLean, VA  22101                   Great Falls, VA
22066
Harvey W. Huntzinger         L. Burwell Gunn, Jr.                Dale B. Peck 139 Dishpan Lane
5525 Beech Ridge Dr.         9111 Tetterton Ave. Stafford, VA 22554                   Fairfax, VA 22030
Vienna, VA  22182
John H. Rust, Jr.            Jones V. Isaac                      James D. Russo 3915 Lake Boulevard
13317 Query Mill Rd.         11304 Taffrail Ct. Annandale, VA 22003                 North Potomac, MD
20878      Reston, VA 20191
</TABLE>
 
                                       -3-
 
<PAGE>
 
         In the event of any increase or decrease in the number of directors
fixed by the Bylaws, all classes of directors shall be increased or decreased as
equally as may be possible. Newly-created directorships resulting from an
increase by not more than two in the authorized number of directors or any
vacancies in the Board of Directors resulting from death, resignation,
retirement, disqualification, removal from office, or other cause, shall be
filled by the affirmative vote of a majority of the directors then in office,
whether or not a quorum. Each director so chosen shall hold office until the
expiration of the term of the director, if any, whom he has been chosen to
succeed or, if none, until the expiration of the term of the class assigned to
the additional directorship to which he has been elected, or until his earlier
death, resignation, or removal. No decrease in the number of directors
constituting the Board of Directors shall shorten the term of any incumbent
director. Any director or the entire Board of Directors may be removed from
office at any time but only for cause and only by the affirmative vote of the
holders of more than two-thirds of each class of the voting stock of the
Corporation then outstanding at a meeting called for that purpose.
 
                                   ARTICLE VI
 
         A.  Limitation of Liability. To the full extent that the Virginia Stock
Corporation Act, as it exists on the date hereof or may hereafter be amended,
permits the limitation or elimination of the liability of directors or officers,
a director or officer of the Corporation shall not be liable to the Corporation
or its stockholders for monetary damages.
 
         B.  Right to Indemnification. The Corporation may indemnify and hold
harmless, to the fullest extent permitted by applicable law as it presently
exists or may hereafter be amended, any person who was or is made or is
threatened to be made a party or is otherwise involved in any action, suit or
proceeding, whether civil, criminal, administrative or investigative (a
"proceeding") by reason of the fact that he, or a person for whom he is the
legal representative, is or was a director, officer, employee or agent of the
Corporation or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation or of a partnership,
joint venture, trust, enterprise or nonprofit entity, including service with
respect to employee benefit plans, against all liability and loss suffered and
expenses reasonably incurred by such person. The Corporation shall be required
to indemnify a person in connection with a proceeding initiated by such person
only if the proceeding was authorized by the Board of Directors of the
Corporation.
 
         C.  Prepayment of Expenses. The Corporation shall pay the expenses
incurred in defending any proceeding in advance of its final disposition,
provided, however, that the payment of expenses incurred by a director or
officer in advance of the final disposition of the proceeding shall be made only
upon receipt of an undertaking by the director or officer to repay all amounts
advanced if it should be ultimately determined that the director or officer is
not entitled to be indemnified under this paragraph or otherwise.
 
         D.  Claims. If a claim for indemnification or payment of expenses under
this paragraph is not paid in full within sixty (60) days after a written
 
                                       -4-
 
<PAGE>
 
claim therefor has been received by the Corporation the claimant may file suit
to recover the unpaid amount of such claim and, if successful in whole or in
part, shall be entitled to be paid the expense of prosecuting such claim. In any
such action the Corporation shall have the burden of proving that the claimant
was not entitled to the requested indemnification or payment of expenses under
applicable law.
 
         E.   Non-Exclusivity of Rights. The rights conferred on any person by
this paragraph shall not be exclusive of any other rights which such person may
have or hereafter acquire under any statute, provision of this certificate of
incorporation, the bylaws, agreement, vote of stockholders or disinterested
directors or otherwise.
 
         F.   Insurance. The Corporation shall have power to purchase and
maintain insurance on behalf of any person who is or was a director, officer,
employee or agent of the Corporation, or is or was serving at the request of the
Corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, against any liability
asserted against him and incurred by him in any such capacity, or arising out of
his status as such, whether or not the Corporation would have the power to
indemnify him against such liability under the provisions of this paragraph.
 
         G.   Other Indemnification. The Corporation's obligation, if any, to
indemnify any person who was or is serving at its request as a director,
officer, employee or agent of another corporation, partnership, joint venture,
trust, enterprise or nonprofit entity shall be reduced by any amount such person
may collect as indemnification from such other corporation, partnership, joint
venture, trust, enterprise or nonprofit enterprise.
 
         H.   Indemnification in the Event of Merger or Consolidation. For the
purposes of this paragraph, references to the Corporation include all
constituent corporations absorbed in a consolidation or merger as well as the
resulting or surviving corporation so that any person who is or was a director,
officer, employee or agent of such a constituent corporation or is or was
serving at the request of such constituent corporation as a director, officer,
employee or agent of another corporation, partnership, joint venture, trust or
other enterprise shall stand in the same position under the provisions of this
section with respect to the resulting or surviving corporation as he would if he
had served the resulting or surviving corporation in the same capacity.
 
         I.   Amendment or Repeal. Any repeal or modification of the foregoing
provisions of this paragraph shall not adversely affect any right or protection
hereunder of any person in respect of any act or omission occurring prior to the
time of such repeal or modification.
 
                                   ARTICLE VII
 
         A.   Amendment to Articles of Incorporation. An amendment to the
Articles of Incorporation of the Corporation shall be approved if a majority of
the votes entitled to be cast by each voting group entitled to vote on an
amendment to the Articles of Incorporation of the Corporation are cast in favor
of such action; provided, that, if such amendment shall have been approved by
less than two-
 
                                       -5-
 
<PAGE>
 
thirds of the directors, holders of more than two-thirds of the issued and
outstanding shares of the Corporation's common stock must vote in favor of such
action.
 
         B.   Merger, Exchange or Sale. Any mercer or share exchange to which
the Corporation is a party or any direct or indirect sale, lease, exchange or
other disposition of all or substantially all of the Corporation's property,
otherwise than in the usual and regular course of business, shall be approved if
a majority of the votes entitled to be cast by each voting group entitled to
vote on such transaction are cast in favor thereof; provided, that, if such
transaction shall have been approved by less than two-thirds of the directors,
holders of more than two-thirds of the issued and outstanding, shares of the
Corporation's common stock must vote in favor of such transaction.
 
         C.   Conditions Upon Approval. This Article shall not affect the power
of the board of directors to condition its submission of any plan of merger,
share exchange, or direct or indirect sale, lease, exchange or other disposition
of all or substantially all of the Corporation's property, otherwise than in the
usual and regular course of business, on any basis, including the requirement of
a greater vote.
 
         IN WITNESS WHEREOF, I set my signature this 24th day of November, 1997.
 
 
                                        /s/ John H. Rust, Jr.
                                        ----------------------------------[SEAL]
                                        John H. Rust, Jr., Incorporator
 

       

 

                              ARTICLES OF AMENDMENT
                       OF THE ARTICLES OF INCORPORATION OF
                         CARDINAL FINANCIAL CORPORATION
 
         1.     The name of the Corporation is Cardinal Financial Corporation.
 
         2.     On August 25, 2000 the Corporation submitted Articles of
Amendment designating a series of Preferred Stock called the 7.25% Cumulative
Convertible Preferred Stock, Series A (the "Series A Preferred Stock"), which
Articles of Amendment were approved by the Clerk of the State Corporation
Commission on August 25, 2000 (such Articles of Amendment are hereinafter
referred to as the "Articles of Amendment Designating the Series A Preferred
Stock").
 
         2.     The Articles of Incorporation of the Corporation are amended by
deleting the third paragraph of the Articles of Amendment Designating the Series
A Preferred Stock and replacing it with the following:
 
                RESOLVED, that 1,412,000 authorized but unissued shares of this
         Corporation's Preferred Stock ($1.00 par value) are hereby designated
         as a series of Preferred Stock called the 7.25% Cumulative Convertible
         Preferred Stock, Series A (the "Series A Preferred Stock"), with the
         following voting powers, rights and preferences.
 
The remaining provisions of the Articles of Amendment Designating the Series A
Preferred Stock are not amended by these Articles of Amendment.
 
         3.     The foregoing amendment was adopted by unanimous written
consent of the Board of Directors of the Corporation.
 
         4.     As of the date hereof, no shares of Series A Preferred Stock
have been issued. Pursuant to Article IV of the Articles of Incorporation of the
Corporation, no shareholder approval of these Articles of Amendment is
necessary.
 
         The undersigned officer of the Corporation declares that the facts
herein stated are true as of October 24, 2000.
 
                                  CARDINAL FINANCIAL CORPORATION
 
 
 
 
                                  ____________________________________________
                                  Name:    /s/ L. Burwell Gunn
                                         -------------------------------------
                                  Title:            President
                                         -------------------------------------
                                         L. Burwell Gunn, President
 
<PAGE>
 
                                                                     
                              ARTICLES OF AMENDMENT
 
                                     TO THE
 
                            ARTICLES OF INCORPORATION
 
                                       OF
 
                         CARDINAL FINANCIAL CORPORATION
 
 
         A.       The name of the Corporation is Cardinal Financial Corporation.
         B.       The following resolution, setting forth the designation and
the number of shares of a series of Preferred Stock ($1.00 par value) of the
Corporation and the relative rights and preferences thereof, was duly adopted by
the Board of Directors of the Corporation at a meeting held on May 22, 2000:
 
         RESOLVED, that 1,376,772 authorized but unissued shares of this
Corporation's Preferred Stock ($1.00 par value) are hereby designated as a
series of Preferred Stock called the 7.25% Cumulative Convertible Preferred
Stock, Series A (the "Series A Preferred Stock"), with the following voting
powers, rights and preferences:
 
         1.       Dividends.
                  ---------
 
                  (a) The holders of the outstanding shares of Series A
Preferred Stock shall be entitled to receive, if, when and as declared by the
Board of Directors of the Corporation, out of any funds legally available
therefor, cash dividends at the rate and payable on the dates hereinafter set
forth. The rate of dividends payable on the Series A Preferred Stock shall be
$.3625 per share per annum and no more. Dividends shall be payable in equal
quarterly installments on the last day of March, June, September and December of
each year, commencing on the last day of the calendar quarter in which the
Corporation and Heritage Bancorp, Inc. merge. Dividends shall be cumulative and
accrue on the Series A Preferred Stock from and after the date of issuance
thereof. Dividends payable on the last day of the calendar quarter in which the
Corporation and Heritage Bancorp, Inc. merge or on any other date which is not
the last day of March, June, September or December shall be calculated on the
basis of a 360 day year and the actual number of days elapsed.
 
                  (b) No dividend whatsoever shall be declared or paid upon, or
any sum set apart for the payment of dividends upon any shares of Parity Stock
for any dividend period unless a like proportionate dividend for the same
dividend period (in proportion to the respective annual dividend rates per share
set forth in the Articles of Incorporation or the respective Articles of
Amendment) shall have been declared and paid upon, or declared and a sufficient
sum set apart for the payment of such dividend upon, all shares of Series A
Preferred Stock outstanding.
 
<PAGE>
 
                  (c)   Unless Dividends Accrued on all outstanding shares of
Series A Preferred Stock and any outstanding shares of Parity Stock due for all
past dividend periods shall have been declared and paid, or declared and a sum
sufficient for the payment thereof set apart, and full dividends (to the extent
that the amount thereof shall have become determinable) on all outstanding
shares of such stock due on the respective next following payment dates shall
have been declare and a sum sufficient for the payment thereof set apart then
(i) no dividend (other than a dividend payable solely in Common Stock) shall be
declared or paid upon, or any sum set apart for the payment of dividends on any
shares of Junior Stock; (ii) no other distribution shall be made upon any shares
of Junior Stock; (iii) no shares of Junior Stock shall be purchased, redeemed or
otherwise acquired for value by the Corporation or by any Subsidiary; and (iv)
no monies shall be paid into or set apart or made available for a sinking or
other like fund for the purchase, redemption or other acquisition for value of
any shares of Junior Stock by the Corporation or any Subsidiary.
 
         2.       Voting Rights.
                  -------------
 
                  The holders of the outstanding shares of Series A Preferred
Stock shall not be entitled to receive notice of, or to participate in, or to
vote on any matter at any meeting of the stockholders of the Corporation, except
to the extent that such holders are afforded a vote by the laws of the
Commonwealth of Virginia in existence at the time any matter requiring such vote
shall arise.
 
         3.       Liquidation.
                  -----------
 
                  In the event of liquidation, dissolution or winding up of the
affairs of the Corporation, the holders of shares of Series A Preferred Stock
then outstanding shall be entitled to be paid in cash out of the net assets of
the Corporation, including its capital, a liquidation price of $5.00 per share,
plus Dividends Accrued to the date of payment, and no more, before any
distribution or payment shall be made to the holders of shares of Junior Stock
and after payment to the holders of the outstanding shares of Series A Preferred
Stock and to the holders of shares of other classes and series of Parity Stock
of the amounts to which they are respectively entitled, the balance of such
assets, if any, shall be paid to the holders of the Junior Stock according to
their respective rights. For the purposes of the preceding sentence, neither the
consolidation of the Corporation with nor the merger of the Corporation into any
other corporation nor the sale, lease or other disposition of all or
substantially all of the Corporation's properties and assets shall, without
further corporate action, be deemed a liquidation, dissolution or winding up of
the affairs of the Corporation. In case the net assets of the Corporation are
insufficient to pay the holders of the outstanding shares of Series A Preferred
Stock and other series of Parity Stock the full preferential amounts to which
they are respectively entitled, the entire net assets of the Corporation shall
be distributed ratably to the holders of the outstanding shares of Series A
Preferred Stock and other series of Parity Stock in proportion to the full
preferential amounts to which they are respectively entitled.
 
         4.       Conversion.
                  ----------
 
 
 
 
 
<PAGE>
 
                  (a) Each holder of any outstanding shares of Series A
Preferred Stock shall have the right, at any time, to convert any of such shares
into Common Stock of the Corporation. Furthermore, as to any shares of Series A
Preferred Stock called for redemption, each such holder shall have the right at
any time prior to the close of business on the fifth full business day preceding
the date fixed for redemption (unless default shall be made by the Corporation
in the payment of the redemption price in which case such right of conversion
shall continue without interruption), to convert any of such shares into shares
of Common Stock of the Corporation. The number of shares of Common Stock into
which each share of Series A Preferred Stock shall be convertible shall be equal
to the number arrived at by dividing $5.00, without any payment or adjustment
for Dividends Accrued, by the conversion price per share of the Common Stock
fixed or determined as hereinafter provided. Such conversion price shall
initially be $6.65 per share, subject to the adjustments hereinafter provided
(such price as adjusted at any time being hereinafter called the "Conversion
Price").
 
                  (b) The holder of any outstanding shares of Series A Preferred
Stock may exercise the conversion right provided in Paragraph (a) above as to
all or any portion of the shares that he holds by delivering to the Corporation
during regular business hours, at the principal office of the Corporation's
transfer agent or such other place as may be designated in writing by the
Corporation, the certificate or certificates for the shares to be converted,
duly endorsed or assigned in blank or endorsed or assigned to the Corporation
(if required by it), accompanied by written notice stating that the holder
elects to convert such shares and stating the name or names (with address and
applicable social security number or other tax identification number) in which
the certificate or certificates or shares of Common Stock are to be issued.
Conversion shall be deemed to have been effected on the date (the Conversion
Date) when such delivery is made. As promptly as practicable thereafter the
Corporation shall issue and deliver to or upon the written order of such holder,
at such office or other place designated by the Corporation, a certificate or
certificates for the number of full shares of Common Stock to which he is
entitled and a payment in cash of any dividends declared and unpaid with respect
to the shares of Series A Preferred Stock so surrendered up to the dividend date
that immediately precedes the Conversion Date. The person in whose name the
certificate or certificates for shares of Common Stock are to be issued shall be
deemed to have become a stockholder of record on the Conversion Date, unless the
transfer books of the Corporation are closed on that date, in which event he
shall be deemed to have become a stockholder of record on the next succeeding
date on which the transfer books are open; but the Conversion Price shall be
that in effect on the Conversion Date, unless the Conversion Date falls after
the date that the Corporation mails a notice of redemption under Section 5(c)
and before the date fixed for redemption, in which case the Conversion Price
shall be that in effect on the date that such notice of redemption is mailed.
 
                  (c) If, for twenty (20) consecutive trading days beginning on
or after the end of the forty second (42nd) calendar month following the
effective date of the merger of the Corporation and Heritage Bancorp, Inc., the
last sale price of the Common Stock exceeds 1.30 multiplied by the Conversion
Price, then, effective at 5:00 p.m. on the last day in such twenty (20) day
period, (y) all outstanding shares of Series A Preferred Stock shall
automatically convert into and become shares of Common Stock, as if each holder
of Series A Preferred Stock exercised the conversion right provided in Section
4(a) and (z) all shares of Series A Preferred
 
<PAGE>
 
Stock, whether or not the certificates therefore shall have been surrendered for
cancellation, shall be deemed no longer to be outstanding for any purpose and
all rights with respect to such shares shall thereupon cease and determine,
except the right to receive certificates for shares of the Corporation's Common
Stock upon surrender of certificates for shares of Series A Preferred Stock the
same manner described in Section 4(b). Promptly following a conversion of shares
of Series A Preferred Stock pursuant to this Section 4(c) the Corporation shall
give written notice of such conversion by first class mail, postage prepaid to
the holders of Series A Preferred Stock at the last addresses shown by the
Corporation's stock transfer records. No delay or imperfection in such notice
will affect the automatic conversion of Series A Preferred Stock into shares of
Common Stock pursuant to this Section 4(c). For purposes of this Section 4(c)
and Section 4(f), the last sale price of the Corporation's Common Stock shall be
deemed to be the last sale price reported by NASDAQ or its successor, but if the
Common Stock is listed on a national stock exchange, the last sale price on any
date shall be deemed to be the last sale price on the exchange on which it
generally has the highest trading volume.
 
                  (d)  The Corporation shall not issue any fraction of a share
upon conversion of shares of the Series A Preferred Stock. If more than one
share of the Series A Preferred Stock shall be surrendered for conversion at any
time by the same holder, the number of full shares of Common Stock issuable upon
conversion thereof shall be computed on the basis of the total number of the
shares of Series A Preferred Stock so surrendered. If any fractional interest in
a share of Common Stock would be deliverable upon conversion, the number of
shares of Common Stock deliverable shall be rounded up to the nearest full
share.
 
                  (e)  The issuance of Common Stock on conversion of outstanding
shares of Series A Preferred Stock shall be made by the Corporation without
charge for expenses or for any tax in respect of the issuance of such Common
Stock, but the Corporation shall not be required to pay any tax or expense which
may be payable in respect of any transfer involved in the issuance and delivery
of shares of Common Stock in any name other than that of the holder of record on
the books of the Corporation of the outstanding shares of Series A Preferred
Stock converted, and the Corporation shall not be required to issue or deliver
any certificate for shares of Common Stock unless and until the person
requesting the issuance shall have paid to the Corporation the amount of such
tax or shall have established to the satisfaction of the Corporation that such
tax has been paid.
 
                  (f)  The Conversion Price shall be subject to the following
adjustments:
 
                       (i)     Whenever the Corporation shall (A) pay a dividend
on its outstanding shares of Common Stock in shares of its Common Stock or
subdivide or otherwise split its outstanding shares of Common Stock, or (B)
combine its outstanding shares of Common Stock into a smaller number of shares,
the Conversion Price in effect at the effective date of the happening of such
event shall be adjusted so that the holders of the Series A Preferred Stock,
upon conversion of all thereof immediately following such event, would be
entitled to receive the same aggregate number of shares of Common Stock as they
would have been entitled to receive immediately following such event if such
shares of Series A Preferred Stock had been converted immediately prior to such
event, or if there is a record date in respect of such
event, immediately prior to such record date.
 
<PAGE>
 
                      (ii)     In case the Corporation, after the date of this
resolution, shall issue rights, warrants or options to subscribe for or purchase
shares of Common Stock, or securities convertible into or exchangeable for
shares of Common Stock, at a price per share less than the lesser of the
Conversion Price or Current Market Value (as hereinafter defined) per share of
Common Stock and if such rights, warrants, options or securities are
exercisable, convertible or exchangeable for a period of more than thirty (30)
days after the date of their issuance, the Conversion Price shall be adjusted so
that the same shall equal the price determined by multiplying the Conversion
Price in effect immediately prior to the issuance of such rights, warrants,
options or securities by a fraction, the numerator of which shall be the number
of shares of Common Stock outstanding at the close of business on the date of
issuance of such rights, warrants, options or securities plus the number of
shares which the aggregate exercise price of the shares of Common Stock called
for by all such rights, warrants, options or securities (excluding any
theretofore exercised, converted or exchanged) would purchase at such Current
Market Value and the denominator of which shall be the number of shares of
Common Stock outstanding at the close of business on the date of issuance of
such rights, warrants, options or securities plus the number of additional
shares of Common Stock called for by all such rights, warrants, options or
securities (excluding any theretofore exercised, converted or exchanged). Such
adjustment shall be made on the date that such rights, warrants or options are
issued. For the purposes of this Section 4(f), the "Current Market Value" per
share of Common Stock on any date shall be deemed to be the average of the last
sale price on each of the twenty (20) consecutive trading days commencing forty
(40) trading days before such date. A trading day, for the purpose of this
resolution, is a day on which securities are traded on the Nasdaq Stock Market
or, if the Common Stock is then listed on any national stock exchange, on such
exchange.
 
                      (iii)    Whenever the Corporation shall make a
distribution to holders of Common Stock of evidences of its indebtedness or
assets (excluding dividends and distributions paid in cash out of funds
available for dividends in accordance with applicable law), the Conversion Price
immediately prior to such distribution shall be adjusted by multiplying such
Conversion Price by a fraction, (y) the numerator of which shall be the
denominator, hereinbelow described, less the fair value (as conclusively
determined in good faith by the Board of Directors of the Corporation) at the
time of such distribution of that portion of the evidences of indebtedness or
assets distributed which is applicable to one share of Common Stock, and (z) the
denominator of which shall be the Current Market Value per share of Common Stock
on the next full business day after the record date fixed for the determination
of the holders of the Common Stock entitled to such distribution. Such
adjustment shall be retroactively effective as of immediately after such record
date.
 
            (g)       Notwithstanding any of the foregoing provisions of this
Section 4, no adjustment of the Conversion Price shall be made if the
Corporation shall issue rights, warrants or options to purchase Common Stock, or
issue Common Stock, pursuant to one or more stock purchase plans, stock option
plans, stock purchase contracts, incentive compensation plans, or other
remuneration plans for employees (including officers) or any shareholder rights
plan of the Corporation or its Subsidiaries adopted or approved by the Board of
Directors of the Corporation before or after the adoption of this resolution.
 
                                       1
 
<PAGE>
 
                  (h) In any case in which this Section 4 provides that an
adjustment of the Conversion Price shall become effective retroactively
immediately after a record date for an event, the Company may defer until the
occurrence of such event issuing to the holder of any shares of Series A
Preferred Stock converted after such record date and before the occurrence of
such event that number of shares of Common Stock issuable upon such conversion
that shall be in addition to the number of shares of Common Stock which were
issuable upon such conversion immediately before the adjustment in the
conversion price required in respect of such event.
 
                  (i) Anything in this Section 4 to the contrary
notwithstanding, no adjustment in the Conversion Price shall be required unless
such adjustment would require an increase or decrease of at least $.25 in such
price; provided, however, that any adjustments which by reason of this paragraph
(h) are not required to be made shall be carried forward and taken into account
in making subsequent adjustments. All calculations under this Section 4 shall be
made to the nearest cent.
 
                  (j) Whenever the Conversion Price and subsequent changes to be
made therein are adjusted pursuant to this Section 4, the Corporation shall (i)
promptly place on file at its principal office and at the office of each
transfer agent for the Series A Preferred Stock, if any, a statement, signed by
the Chairman or President of the Corporation and by its Treasurer, showing in
detail the facts requiring such adjustment and a computation of the adjusted
Conversion Price, and shall make such statement available for inspection by
shareholders of the Corporation, and (ii) cause a notice to be mailed to each
holder of record of the outstanding shares of Series A Preferred Stock stating
that such adjustment has been made and setting forth the adjusted Conversion
Price. Unless the change in the Conversion Price is caused as a result of action
described in subparagraph (i) of paragraph (e) of this Section 4, it shall be
accompanied by a letter from the Corporation's independent public accountants
stating that the change has been made in accordance with the provisions of this
resolution.
 
                  (k) In the event of any merger, share exchange or similar
transaction to which the Corporation is a party, except (i) a merger in which
the Corporation is the surviving corporation or (ii) a share exchange in which
the Corporation's shares are issued to shareholders of another corporation, the
plan of merger, plan of share exchange or comparable document shall provide that
each share of Series A Preferred Stock then outstanding shall be converted into
or exchanged for the kind and amount of stock, other securities and property
receivable upon such merger, share exchange or similar transaction by a holder
of the number of shares of Common Stock of the Corporation into which such share
of Series A Preferred Stock might have been converted immediately prior thereto.
 
                  (l) Shares of Common Stock issued on conversion of shares of
Series A Preferred Stock shall be issued as fully paid shares and shall be
nonassessable by the Corporation. The Corporation shall, at all times, reserve
and keep available for the purpose of effecting the conversion of the
outstanding shares of Series A Preferred Stock such number of its duly
authorized shares of Common Stock as shall be sufficient to effect the
conversion of all outstanding shares of Series A Preferred Stock.
 
<PAGE>
 
                  (m) Shares of Series A Preferred Stock converted as provided
herein shall not thereafter be reissued as shares of Series A Preferred Stock,
but, upon issuance by the State Corporation Commission of Virginia or any
successor thereof of a certificate of reduction or document of similar effect,
such shares shall become authorized and unissued shares of Preferred Stock which
may be designated as shares of any other series. No additional shares of
Preferred Stock, however, may be classified as Series A Preferred Stock.
 
         5.       Redemption.
                  ----------
 
                  (a) The Corporation may, at its option at any time after
December 31, 2020 and from time to time thereafter, redeem all or any portion of
the outstanding shares of Series A Preferred Stock at a redemption price of
$5.00 per share, plus in each case Dividends Accrued to the date fixed for
redemption. Additionally and at the same redemption price, the Corporation may
redeem all or any portion of the Series A Preferred Stock after a merger, share
exchange or similar transaction to which the Corporation is a party is approved
by the holders of the Common Stock and not approved by holders of the Series A
Preferred Stock; provided such transaction is submitted to the holders of the
Series A Preferred Stock on terms that are in accordance with Section 4(k); and,
provided further, that no redemption may occur and no redemption notice may be
sent before the end of the forty second (42nd) month following the effective
date of the merger of the Corporation and Heritage Bancorp, Inc. unless such
notice states that the redemption price will be $5.00 per share, plus Dividends
Accrued to the date fixed for redemption, plus an amount equal to all dividends
that would accrue if the Series A Preferred Stock remained outstanding until the
end of the forty second (42nd) month following the effective date of the merger
of the Corporation and Heritage Bancorp, Inc. and no later.
 
                  (b) In case less than all of the outstanding shares of Series
A Preferred Stock are to be redeemed, not more than 60 days prior to the date
fixed for redemption the Corporation shall select the shares to be redeemed by
prorating the total number of shares to be so redeemed among all holders thereof
in proportion, as nearly as may be, to the number of shares registered in their
respective names, by lot or in such other equitable manner as the Board of
Directors may determine. The Corporation in its discretion may determine the
particular certificates (if there are more than one) representing shares
registered in the name of a holder which are to be redeemed.
 
                  (c) Not less than thirty (30) nor more than sixty (60) days
prior to the date fixed for any redemption pursuant to paragraph (a) of this
Section 5, notice of redemption shall be given by first class mail, postage
prepaid, to the holders of record of the outstanding shares of Series A
Preferred Stock to be redeemed at their last addresses as shown by the
Corporation's stock transfer records. The notice of redemption shall set forth
the number of shares to be redeemed, the date fixed for redemption, the
applicable redemption price (including the amount of Dividends Accrued to the
date fixed for redemption), and the place or places where certificates
representing shares to be redeemed may be surrendered. In case less than all
outstanding shares are to be redeemed, the notice of redemption shall also set
forth the numbers of the certificates representing shares to be redeemed and, in
case less than all shares represented by any such certificate are to be
redeemed, the number of shares represented by such certificate to be redeemed.
 
<PAGE>
 
                  (d) When a notice of redemption of any outstanding shares of
Series A Preferred Stock shall have been duly mailed as hereinabove provided, on
or before the date fixed for redemption the Corporation shall deposit in cash
funds sufficient to pay the redemption price (including Dividends Accrued to the
date fixed for redemption) of such shares in trust for the benefit of the
holders of the shares to be redeemed with any bank or trust company in the City
of Richmond, State of Virginia, having capital and surplus aggregating at least
$50,000,000 as of the date of its most recent report of financial condition and
named in such notice, to be applied to the redemption of the shares so called
for redemption against surrender of the certificates representing shares so
redeemed for cancellation. Except as set forth in Section 4(a), from and after
the time of such deposit all shares for the redemption of which such deposits
shall have been so made shall, whether or not the certificates therefor shall
have been surrendered for cancellation, be deemed no longer to be outstanding
for any purpose and all rights with respect to such shares shall thereupon cease
and determine except the right to receive payment of the redemption price
(including Dividends Accrued to the date fixed for redemption), but without
interest. Any interest accrued on such funds shall be paid to the Corporation
from time to time.
 
                  (e) The Corporation shall also have the right to acquire
outstanding shares of Series A Preferred Stock otherwise than by redemption,
pursuant to this Section 5, from time to time, for such consideration as may be
acceptable to the holders thereof; provided, however, that if all Dividends
Accrued on all outstanding shares of Series A Preferred Stock shall not have
been declared and paid or declared and a sum sufficient for the payment thereof
set apart neither the Corporation nor any Subsidiary shall so acquire any shares
of such series except in accordance with a purchase offer made on the same terms
to all the holders of the outstanding shares of Series A Preferred Stock.
 
                  (f) Shares of Series A Preferred Stock redeemed or otherwise
acquired by the Corporation shall not thereafter be disposed of as shares of
Series A Preferred Stock, but, upon issuance by the State Corporation Commission
of Virginia or successor thereof of a Certificate of Reduction or document of
similar effect, such shares shall become authorized and unissued shares of
Preferred Stock which may be designated as shares of any other series. No
additional shares of preferred stock, however, may be classified as Series A
Preferred Stock.
 
         6.       Definitions
 
                  -----------
 
                  For the purposes of this resolution, the following terms shall
have the following meanings:
 
                  "Capital Stock" means the Capital Stock of any class or series
(however designated) of the Corporation.
 
                  "Common Stock" means the Common Stock of the Corporation
($1.00 par value) as constituted on the date of this Resolution, or shares of
any other class of Capital Stock into which such Common Stock is reclassified
after such date.
 
<PAGE>
 
                  "Dividends Accrued" means an amount equal to the sum of all
dividends required to be paid on the shares of Series A Preferred Stock from the
date of issue of the shares of Series A Preferred Stock to the date to which the
determination is to be made, whether or not such amount or any part thereof
shall have been declared as dividends and whether there shall be or have been
any funds out of which such dividends might legally be paid, less the amount of
dividends declared and paid and, if any dividends have been declared and set
apart for payment but not paid, the amount so set apart for the payment of such
dividends. Accrued Dividends for any period less than a full calendar quarter
shall be calculated on the basis of the actual number of days elapsed over a
360-day year.
 
                  "Junior Stock" means any Capital Stock ranking as to dividends
and as to rights in liquidation, dissolution or winding up of the affairs of the
Corporation junior to the Series A Preferred Stock.
 
                  "Parity Stock" means shares of any series of the Corporation's
Preferred Stock and any shares of Capital Stock ranking as to dividends and/or
as to the rights in liquidation, dissolution or winding up of the affairs of the
Corporation equally with the Series A Preferred Stock.
 
                  "Prior Stock" means any Capital Stock ranking as to dividends
or as to rights in liquidation, dissolution or winding up of the affairs of the
Corporation prior to the Series A Preferred Stock.
 
                  "Subsidiary" means any corporation, a majority of the
outstanding voting stock of which is owned, directly or indirectly, by the
Corporation or by the Corporation and one or more Subsidiaries.
 
                                        CARDINAL FINANCIAL CORPORATION
 
                                        By: /s/ L. Burwell Gunn, Jr.
                                           -------------------------------------
                                              L. Burwell Gunn, Jr., President
 
                                        By: /s/ Nancy K. Falck
 
                                           -------------------------------------
                                                 Nancy K. Falck, Secretary