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  CLIFF’S AUTO BODY, INC. v. CARL M. GRENIER
                  (AC 39988)
               DiPentima, C. J., and Lavine and Sheldon, Js.

                                  Syllabus

The plaintiff C Co. sought to foreclose a judgment lien on certain real
   property owned by the defendant. In an underlying debt collection
   action, which concerned a debt that arose out of a motor vehicle accident
   involving D, the defendant’s deceased mother, C Co. had secured a
   judgment in its favor against D in December, 2008. The trial court also
   awarded C Co. interest but did not set the rate at which the interest
   would accrue. C Co. thereafter placed a judgment lien on certain of D’s
   real property. D then appealed from the judgment to this court, which
   dismissed the appeal for lack of a final judgment because there was an
   unresolved claim for discretionary prejudgment interest. In April, 2010,
   C Co. filed a motion for clarification requesting the trial court to enter
   an order setting the rate of prejudgment interest. The court granted the
   motion and ordered prejudgment and postjudgment interest at a rate
   of 10 percent per year. Following D’s death, the defendant became the
   owner of the subject property. Thereafter, C Co. commenced this action
   against the defendant seeking to foreclose the judgment lien. The defen-
   dant filed a motion to dismiss on the grounds that the judgment lien
   was not valid, that the court lacked subject matter jurisdiction and that
   the lien did not specify the rate of interest. The court denied the motion
   and rendered a judgment of foreclosure by sale in favor of B Co., which
   had been substituted as the plaintiff. On the defendant’s appeal to this
   court, held that the trial court improperly rendered a judgment of foreclo-
   sure by sale, as the judgment lien was invalid as a matter of law and
   could not have served as the basis for the judgment of foreclosure by
   sale; the judgment lien was predicated on the judgment in the debt
   collection action, which did not state the rate of interest and, therefore,
   did not specify with certainty the amount for which it was rendered, nor
   was the amount ascertainable from the record or by mere mathematical
   computation, and because this court previously had determined that
   the judgment in the debt collection action was not a final judgment and
   C Co. had failed to timely file a motion to open within four months of
   the judgment to obtain an award of interest that included the rate of
   interest, the trial court in that action lacked the power to determine
   the rate of prejudgment and postjudgment interest more than fifteen
   months after the judgment had been rendered.
     Argued October 24, 2017—officially released February 27, 2018

                            Procedural History

  Action to foreclose a judgment lien on certain of the
defendant’s real property, and for other relief, brought
to the Superior Court in the judicial district of New
London, where Basley Holdings, Inc., was substituted
as the plaintiff; thereafter, the court, Hon. Robert C.
Leuba, judge trial referee, denied the defendant’s
motion to dismiss and rendered a judgment of foreclo-
sure by sale, from which the defendant appealed to this
court. Reversed; judgment directed.
   James J. Schultz, for the appellant (defendant).
  Kerin M. Woods, with whom, on the brief, was
Rachael M. Gaudio, for the appellee (substitute
plaintiff).
                           Opinion

   LAVINE, J. The defendant, Carl M. Grenier, appeals
from the judgment of foreclosure by sale rendered by
the trial court in favor of the plaintiff Basley Holdings,
Inc.1 The defendant’s principal claim on appeal is that
it was improper for the court, Hon. Robert C. Leuba,
judge trial referee, to deny his motion to dismiss for
lack of subject matter jurisdiction.2 We reverse the judg-
ment of the trial court.
   The following historical facts and procedural history
are relevant to our resolution of the defendant’s appeal.
The debt at issue arose out of a motor vehicle accident
involving the defendant’s deceased mother, Frances
Grenier (decedent), many years ago. The plaintiff under-
took to repair the decedent’s vehicle, but for reasons
not relevant to the present matter, the decedent refused
to pay the plaintiff for its efforts. The plaintiff, therefore,
brought a debt collection action against the decedent
and secured a judgment in its favor in the amount of
$9887.22 on December 30, 2008. The court, Riley, J.,
also awarded the plaintiff interest pursuant to General
Statutes § 37-3a3 but did not set the rate at which the
interest would accrue.4 On January 2, 2009, the plaintiff
placed a judgment lien in the amount of $9887.22 on
the decedent’s real property at 82 Pendleton Hill Road
in Voluntown (property). The decedent appealed from
the judgment against her, but, on April 15, 2010, this
court sua sponte ordered the appeal dismissed for want
of an appealable final judgment.5 The judgment was not
a final judgment for purposes of appeal because there
was an unresolved claim for discretionary prejudgment
interest. See Balf Co. v. Spera Construction Co., 222
Conn. 211, 214, 608 A.2d 682 (1992) (prejudgment inter-
est part of compensation due).
  On April 13, 2010, more than fifteen months after
Judge Riley rendered judgment in the debt collection
action, the plaintiff filed a motion for clarification ask-
ing the court to set the amount of prejudgment interest.
On April 26, 2010, Judge Riley ordered prejudgment and
postjudgment interest at the rate of 10 percent per year.
   In May, 2014, the defendant became the owner of
the property by devise due to his mother’s death. The
plaintiff commenced the present action against the
defendant in early 2015 to foreclose the judgment lien
it had placed on the property in January, 2009. The
defendant, who was then self-represented, responded
by filing several special defenses grounded in our pro-
bate statutes and thereafter filed a motion for summary
judgment on those grounds. The motion for summary
judgment was denied by the court, Cosgrove, J. The self-
represented defendant subsequently filed an amended
answer and special defenses and an amended motion
for summary judgment on the ground that the judgment
lien was flawed because General Statutes § 52-328 (b)
requires a judgment creditor to file a judgment lien
within four months of the final judgment.6 Judge Cos-
grove sustained the plaintiff’s objection to the amended
motion for summary judgment on August 25, 2015, stat-
ing that the plaintiff obtained a valid judgment against
the decedent and when the judgment was not paid, the
plaintiff placed a lien on the property.
   The defendant obtained counsel, who filed numerous
motions to dismiss the action on the ground, among
others, that the judgment lien was flawed and unen-
forceable because it was predicated on a judgment that
was not final. On October 28, 2015, the defendant filed
a motion to dismiss on the ground that the court lacked
subject matter jurisdiction. On April 21, 2016, the court,
Devine, J., denied the defendant’s motion to dismiss
after finding that the plaintiff had filed the lien within
four months of when the judgment was rendered against
the decedent. The court, relying on Mac’s Car City,
Inc. v. DiLoreto, 238 Conn. 172, 183, 679 A.2d 340 (1996),
concluded that the judgment lien was valid even though
the decedent had taken an appeal.7 Subsequently, the
defendant filed numerous motions to dismiss, for rear-
gument, and for clarification, all of which were denied.
On November 25, 2016, when the foreclosure matter
was scheduled to begin trial, the defendant filed another
motion to dismiss and, on November 29, 2016, a motion
for a continuance. The court, Nazzaro, J., denied the
motion for a continuance.8
   The matter was tried before Judge Leuba. Following
the presentation of evidence, Judge Leuba learned that
Judge Nazzaro had not ruled on the defendant’s motion
to dismiss and, therefore, heard the arguments of coun-
sel.9 The court denied the defendant’s motion to dismiss
predicated on the grounds that there was no valid judg-
ment lien, that the court lacked subject matter jurisdic-
tion, and that the lien placed in evidence did not specify
the rate of interest. In denying the motion to dismiss,
Judge Leuba cited Judge Devine’s memorandum of deci-
sion denying one of the defendant’s prior motions to
dismiss. Judge Leuba thereafter rendered a judgment
of foreclosure by sale in favor of the plaintiff on Novem-
ber 30, 2016.10
  The defendant appealed. He claims, among other
things, that the court improperly rendered a judgment
of foreclosure by sale on the basis of an invalid judg-
ment lien in the debt collection action. We agree that
the judgment lien submitted at the foreclosure hearing
was invalid and, therefore, conclude that the court erred
in rendering the judgment of foreclosure by sale.
  The determinative question before us is whether the
court properly rendered a judgment of foreclosure by
sale. An appellate court ordinarily reviews ‘‘a trial
court’s decision to grant foreclosure for an abuse of
discretion. . . . When, however, the claims on appeal
are not targeted at the trial court’s exercise of discre-
tion, but at a subsidiary legal conclusion, our review is
plenary.’’ (Citation omitted.) ARS Investors II 2012-1
HVB, LLC v. Crystal, LLC, 324 Conn. 680, 685, 154 A.3d
518 (2017). The legal issue before us is whether the
court properly concluded that the judgment lien on the
property was valid.
   The following facts are relevant to our decision. Two
days before the decedent’s appeal was dismissed for
lack of a final judgment, the plaintiff requested that
Judge Riley enter an order setting the rate of prejudg-
ment interest in the debt collection action. Judge Riley
granted the plaintiff’s request in April, 2010, more than
fifteen months after he had rendered judgment in the
debt collection action. He, however, lacked the power
to do so.
   ‘‘Our case law establishes that any substantive modifi-
cation of a judgment constitutes an opening of the judg-
ment. The issue of whether a particular action by the
trial court opens the judgment typically arises when
the court alters the judgment more than four months
after the judgment was rendered and a party challenges
the court action as an untimely opening of the judgment
. . . .’’ Commissioner of Transportation v. Rocky
Mountain, LLC, 277 Conn. 696, 705, 894 A.2d 259 (2006).
General Statutes § 52-212a provides in relevant part:
‘‘[A] civil judgment or decree rendered in the Superior
Court may not be opened or set aside unless a motion
to open or set aside is filed within four months following
the date on which it was rendered or passed. . . .’’
Both § 52-212a and Practice Book § 17-411 provide that
the trial court lacks the power to open a judgment
more than four months after the judgment is rendered.
Commissioner of Transportation v. Rocky Mountain,
LLC, supra, 706.
   In the present case, Judge Riley fixed the rate of
prejudgment interest and added postjudgment interest
to the debt collection judgment more than fifteen
months after the judgment was rendered. The defendant
claims that assigning the rate of interest on the debt
collection judgment constituted a substantive change
in the judgment. We agree; adding an award of postjudg-
ment interest to a damages award is a substantive modi-
fication of the judgment. Id., 707, citing Goldreyer v.
Cronan, 76 Conn. 113, 117, 55 A. 594 (1903). Because
the plaintiff did not seek to have the debt collection
judgment opened to determine the rate of prejudgment
interest within four months of December 30, 2008, when
the judgment was rendered, the court lacked the power
to determine the rate of prejudgment interest and to
add postjudgment interest in April, 2010.
   The case of Unifund CCR Partners v. Schaeppi, 140
Conn. App. 281, 59 A.3d 282 (2013), informs our decision
in the present case. Unifund CCR Partners was a debt
collection action in which the trial court, Miller, J.,
rendered judgment in favor of Unifund CCR Partners
(Unifund) on June 19, 2006. Id., 283, citing Unifund
CCR Partners v. Schaeppi, 126 Conn. App. 370, 372, 11
A.3d 723 (2011). Unifund placed a judgment lien on real
property owned by the Schaeppis on July 18, 2006. Id.
On August 25, 2006, Unifund filed a motion for an order
of weekly payments, which the court granted on Sep-
tember 11, 2006. Id. Unifund initiated a foreclosure
action against the Schaeppis and filed a motion for
summary judgment as to liability. The trial court, Hon.
Robert Satter, judge trial referee, denied the motion on
exemption grounds but noted that the judgment and
lien against the Schaeppis did not state the amount
of the lien. Id., 284. Unifund filed a motion seeking
clarification of the June 19, 2006 judgment, but Judge
Miller found that there never was a finding as to the
amount of the debt. Id., 285. Consequently, there was
no judgment to clarify. Id.
   Thereafter, the Schaeppis filed their own motion for
summary judgment on the basis of Judge Satter’s obser-
vations in his memorandum of decision regarding the
issue of liability. Id. By memorandum of decision filed
October 15, 2008, Judge Satter granted the Schaeppis’
motion for summary judgment and stated, as a matter
of law, ‘‘a judgment of no amount, underlying a judg-
ment lien in an incorrect amount cannot form the basis
of a foreclosure action.’’ (Internal quotation marks omit-
ted.) Id. Unifund appealed to this court arguing that the
June 19, 2006 judgment was a full and final judgment
and, in the alternative, that the order for weekly pay-
ments entered on September 11, 2006, was a money
judgment. Id.
   This court rejected both of Unifund’s arguments and
affirmed the summary judgment in favor of the
Schaeppis. Id., 286. This court determined that the ‘‘June
19, 2006 judgment was not a full and final judgment
because it did not specify with certainty the amount
for which it was rendered, nor was the amount ascer-
tainable from the record or by mere mathematical com-
putation. . . . Without deciding whether the
installment payment order of September 11, 2006, was
a money judgment, this court concluded that it was
impossible for it to have served as the basis for the
judgment lien, as the judgment lien was recorded weeks
before the court entered its installment payment order.’’
(Citation omitted; internal quotation marks omitted.)
Id.
  After this court affirmed the judgment granting the
Schaeppis’ motion for summary judgment, Unifund filed
a motion to open and modify the judgment of June 19,
2006. The motion was denied, as were the subsequent
motions for reargument and reconsideration. Id. Uni-
fund then asked Judge Miller to articulate his reasons
for denying its motion to open the judgment. Id. Judge
Miller articulated that the judgment Unifund sought to
open lacked a specific dollar amount and, therefore,
was not a valid judgment, and the court did not ‘‘have
the ability to open a judgment that was never really
a judgment.’’ (Internal quotation marks omitted.) Id.
Unifund thereafter appealed once more to this court. Id.
   In its second appeal, Unifund argued that Judge Miller
abused his discretion by failing to open the June 19,
2006 judgment because the court has authority pursuant
to § 52-212a in cases where the judgment was obtained
by mutual mistake. Id., 287. This court rejected Uni-
fund’s argument on the ground that it rested ‘‘on the
faulty premise that there exists a judgment to open.’’
Id. Because this court already had determined that ‘‘the
judgment rendered on June 19, 2006, was not a full and
final judgment; Unifund CCR Partners v. Schaeppi,
supra, 126 Conn. App. 380; it declined to engage in that
analysis for the second time.’’ (Internal quotation marks
omitted.) Unifund CCR Partners v. Schaeppi, supra,
140 Conn. App. 287.
   In the present case, the judgment lien placed on the
property on January 2, 2009, was predicated on the
December 30, 2008 judgment in the debt collection
action. In the decedent’s appeal, this court determined
that the debt collection judgment was not a final judg-
ment because the rate of interest had not been set.
The plaintiff failed to open timely the debt collection
judgment to obtain an award that set the rate of prejudg-
ment interest. Moreover, for the sake of argument only,
even if the plaintiff timely had opened the debt collec-
tion judgment and had obtained a judgment that incor-
porated the rate of interest, in order to obtain a valid
judgment lien, it was required to file a new judgment
lien on the property. There is no evidence that the
plaintiff has filed a judgment lien on the property since
January 2, 2009.12 General Statutes § 52-380a (a) pro-
vides in relevant part that ‘‘[a] judgment lien, securing
the unpaid amount of any money judgment, including
interest and costs, may be placed on any real property
by recording, in the town clerk’s office of the town
where the real property lies, a judgment lien certificate
. . . containing . . . the date on which the judgment
was rendered, and the original amount of the money
judgment and the amount due thereon . . . .’’ Pursuant
to § 52-328 (b), the lien must be recorded within four
months of judgment.
  We conclude, therefore, that the judgment lien sub-
mitted in evidence in the present foreclosure action
was invalid as a matter of law and could not serve as
a basis for the judgment rendered by the court. The
judgment lien was predicated on a judgment that did
not state the rate of interest and, therefore, did not
specify with certainty the amount for which it was ren-
dered, nor was the amount ascertainable from the
record or by mere mathematical computation. We,
therefore, reverse the judgment of foreclosure by sale.
  The judgment is reversed and the case is remanded
with direction to grant the defendant’s motion to dis-
miss for lack of subject matter jurisdiction.
      In this opinion the other judges concurred.
  1
     Following the commencement of the present action by the named plain-
tiff, Cliff’s Auto Body, Inc., its successor in interest, Basley Holdings, Inc.,
was substituted as the party plaintiff. For convenience, we refer in this
opinion to the named plaintiff and the substitute plaintiff collectively as
the plaintiff.
   2
     The defendant also claims that the court improperly (1) rendered a
judgment of foreclosure by sale in the absence of a final judgment, (2)
deferred to the ruling of the court, Divine, J., on his motion to dismiss, (3)
ordered him to trial under the pain of sanctions when a motion to dismiss
was pending, (4) rendered a decision on a judgment that had not timely
been opened, (5) permitted the plaintiff to put documents into evidence
without authenticating them or laying a foundation, and (6) violated his
right to due process on numerous grounds.
   The plaintiff states that the issue on appeal is whether the court properly
rendered a judgment of foreclosure by sale pursuant to General Statutes
§ 52-380a. We reverse the judgment of foreclosure by sale for the lack of a
valid underlying judgment. We therefore need not address the remainder
of the defendant’s claims.
   3
     General Statutes § 37-3a provides in relevant part: ‘‘[I]nterest at the rate
of ten percent a year and no more, may be recovered and allowed in civil
actions . . . as damages for the detention of money after it becomes pay-
able. . . .’’
   4
     ‘‘In Sears, Roebuck & Co. v. Board of Tax Review, 241 Conn. 749, 765–66,
699 A.2d 81 (1997), this court held that the 10 percent interest rate set forth
in § 37-3a is not a fixed rate, but rather the maximum rate of interest that
a trial court, in its discretion, can award.’’ Gianetti v. Meszoros, 268 Conn.
424, 426, 844 A.2d 851 (2004).
   5
     This court issued the following order: ‘‘After a hearing as to why the
defendant’s appeal should not be dismissed for lack of a final judgment
because there has been no final determination regarding the amount of
damages, in light of the fact that the trial court, in rendering judgment in
accordance with the factfinder’s report, failed to specify the rate at which
prejudgment interest should be calculated; see Gianetti v. Meszoros, 268
Conn. 424, 426 [844 A.2d 851] (2004); it is hereby ordered that this appeal
is dismissed.’’
   6
     General Statutes § 52-328 (b) provides that no real estate may be subject
to attachment ‘‘unless the judgment creditor places a judgment lien on the
real estate within four months after a final judgment.’’
   7
     In his memorandum of decision, Judge Devine stated in part: ‘‘The ruling
was appealed and then remanded to the trial court to determine the amount
of interest. Even though the Appellate Court ruled that the trial court’s
judgment was not final, the lien filed after the original judgment remains
valid.’’
   The order dismissing the appeal contains no remand order. See footnote
5 of this opinion.
   8
     Judge Nazzaro issued the following order: ‘‘Counsel on the eve of trial
filed no less than its third motion to dismiss, one of which was withdrawn and
then refiled and then denied on the merits. Counsel moved for reargument
on dismissal. That motion was denied. Counsel moved for clarification of
rulings. Those motions were denied. Subject matter jurisdiction has already
been argued and determined. Counsel again attempts to revive dismissal
on this basis on the eve of trial. The motion to continue the court trial one
day before trial is denied. The parties are ordered to appear and try the
case in accordance with the trial management report. Failure to appear and
or proceed may result in sanctions and or dismissal. This motion is untimely,
is prejudicial and if granted would permit unreasonable delay.’’
   9
     In his argument, counsel for the defendant referred to Unifund CCR
Partners v. Schaeppi, 140 Conn. App. 281, 59 A.3d 282 (2013). He argued,
in relevant part, that a judgment is not a full or final judgment when it does
not specify with certainty the amount for which it was rendered, nor was
the amount ascertainable from the record or by mere mathematical computa-
tion. ‘‘It’s been argued that you can’t look at the record and ascertain the
amount of the judgment, but the lien was filed in January, 2009. In 2010,
there was an untimely opening where [Judge Riley] specified interest at 10
percent. Well, the lien should have been refiled, if anything, to have a
position, but it was not. As I said, what was presented to the court today
was a lien that does not specify interest, it is not of any specified amount
in total, and there has been no testimony, no evidence, to the contrary.’’
  10
     The court found the debt to be $21,497.72. The value of the property
was $200,000. The court also awarded attorney’s fees of $7150, an appraisal
fee of $600, and a title search fee of $250.
  11
     Practice Book § 17-4 (a) provides in relevant part: ‘‘Unless otherwise
provided by law . . . any civil judgment or decree rendered in the superior
court may not be opened or set aside unless a motion to open or set
aside is filed within four months succeeding the date on which notice was
sent. . . .’’
  12
     The copy of the judgment lien attached to the plaintiff’s complaint is
dated January 2, 2009, and states the amount of damages as $9887.22.
