Thorup v. Thorup

2024 UT App 93
THE UTAH C OURT OF APPEALS
M ONA THORUP ,
Appellee,
v.
M ARCUS THORUP ,
Appellant.
Opinion
No. 20220583-CA
Filed July 5, 2024
Third District Court, Salt Lake Department
The Honorable Amy J. Oliver
Commissioner Joanna Sagers
No. 204906416
Jonathan G. Winn, Attorney for Appellant
Jenna Hatch, Attorney for Appellee
JUDGE R YAN M. HARRIS authored this Opinion, in which
JUDGES M ICHELE M. C HRISTIANSEN F ORSTER and JOHN D. LUTHY
concurred.
HARRIS, Judge:
¶1 	In this case, we are asked to consider whether the district
court properly allocated—as between a divorcing couple—the
equity in the house in which the couple lived during their
marriage. In particular, Marcus Thorup challenges the court’s
determination that substantial portions of the value of the house,
which was originally his separate property, became commingled
into the marital estate. We find merit in many of Marcus’s
arguments, and therefore reverse the court’s equity allocation
order and remand the case for further proceedings.

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BACKGROUND
¶2 	Marcus and Mona Thorup married in 1986.1 Eleven years
later, in 1997, they moved into a new house (the House) built—at
the apparent cost of $445,000—by Marcus’s father’s construction
company. For the next seven years, the House was titled in the
name of Marcus’s father’s company, and Marcus and Mona lived
there rent-free. During some of this time, Marcus and Mona
obtained a homeowners insurance policy that listed both of them
as “owners” of the House, even though that was not actually the
case. And for a year or so around 1997, Mona’s mother lived in a
separate apartment on the property, and she paid Marcus and
Mona some $13,000 that went toward the costs associated with
building the separate apartment.
¶3 	In May 2004, Marcus’s father (through his company)
“gifted” the House to Marcus “as an inheritance.” Thereafter, title
to the House was in Marcus’s name; Mona was never placed on
title. In December 2004, Marcus used the House as collateral for a
$150,000 loan. Marcus later testified that the proceeds from the
loan were not spent on the House but, instead, were spent on
marital matters, such as medical bills, credit card bills, some other
unspecified “investments,” and a payment on the couple’s “cabin
lot.” Over the next ten years, the loan was fully repaid, entirely
with marital funds.
¶4 	Between 1997 and 2020, Marcus, Mona, and their children
lived in and maintained the House. They also made some
improvements to the House over that time. For purposes of this
dispute, Marcus retained an expert who determined that the out-
of-pocket cost of the family’s improvements had been $12,171,
1. Because the parties share the same last name, we use their first
names for clarity, with no disrespect intended by the apparent
informality.

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and that the family’s maintenance of and improvements to the
House “contributed about $20,000 to its current value.”
¶5 	In 2020, Mona filed this divorce action and asked (among
other things) that the House and all its equity be awarded to her.
Marcus responded by filing a counterclaim in which he contended
that the House was an “inheritance from his father” and was his
“separate property.” This dispute eventually worked its way to
trial, and the parties agreed, by written stipulation, to resolve the
issue by way of an “informal custody trial” before a domestic
relations commissioner, a procedure usually limited to resolution
of custody disputes and whose parameters are set forth in rule
4-904 of the Utah Code of Judicial Administration. Under this
procedure, the parties agreed to “present[] their case[s]” to the
commissioner, under oath, without questioning by attorneys. In
addition to providing their own testimony, the parties agreed that
they could each “present any documents they want[ed] the [c]ourt
to consider” and that, “[a]fter the [c]ourt [had] heard from both
parties,” only then would attorneys be allowed “to make legal
argument.” In stipulating to this procedure, the parties agreed to
“waive the normal question and answer manner of trial” and to
“waive the rules of evidence,” and they agreed that “[t]he other
party [could] tell the [c]ourt anything he or she feels is relevant.”
The parties also waived their right to “challenge any of the
documents 	or 	testimony 	that 	was 	considered” 	by 	the
commissioner during the informal trial, and they agreed that
“[t]he only issue on appeal [would] be whether the [c]ourt abused
its discretion in reaching its findings and conclusions.”
¶6 	During the course of the informal trial—which took place
over parts of two trial days—the commissioner heard from
Marcus and Mona, who testified (largely through proffer by
counsel) about the events described above. In addition, the parties
by stipulation submitted sworn declarations and other similar
documents 	from 	other 	witnesses, 	which 	evidence 	the
commissioner 	accepted 	and 	considered. 	And 	the 	parties’

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attorneys made extensive arguments, both in written briefs filed
prior to the trial and in oral arguments made during the trial.
¶7 	Mona took the position that, even if the House was
originally Marcus’s separate property, “the separate property
converted into marital property during the marriage.” She made
two specific arguments in this regard, asserting both (a) that she
had contributed to the value of the House through maintenance
and 	improvements, 	and 	had 	thereby 	acquired 	an 	equitable
interest in it, and (b) that the House had been commingled into
the marital estate. Marcus, on the other hand, took the position
that the House was, and always had been, his separate property,
and that it had not been commingled into the marital estate. He
acknowledged 	that 	“Mona 	may 	have 	a 	contribution 	claim”
regarding the House, but he pointed to evidence indicating that
the family’s contributions had increased the value of the House
by only $20,000, and he argued that, at most, Mona was therefore
entitled to only $10,000 of the House’s total value.
¶8 	At 	the 	conclusion 	of 	the 	trial, 	and 	after hearing 	the
arguments, the commissioner made an oral ruling, determining
that much of the House’s value—$150,000 of its original value,
plus all of its appreciation—had been commingled into the
marital 	estate. 	As 	support 	for 	this 	determination, 	the
commissioner 	noted 	that 	the 	marital 	estate 	had 	repaid 	the
$150,000 loan that used the House as collateral, and reasoned
that 	the 	loan 	indicated 	“that 	the 	family 	in 	essence 	bought
that mortgage and paid it back.” The commissioner also relied
on the facts that, during the period before Marcus was gifted
the 	House, 	the 	parties 	obtained 	homeowners 	insurance
indicating that they were both owners of it and that Mona’s
mother had paid $13,000 toward “the mother-in-law apartment
being enhanced.” And the commissioner found relevant the fact
that Mona had been “responsible for maintaining” the House
and 	its 	“landscaping.” 	The 	commissioner 	also 	found—by
averaging two appraisals—that the House was worth $312,500 in

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2004 when it was gifted to Marcus and was worth $765,000 at the
time of trial. The commissioner then concluded that Marcus
should receive $162,500 ($312,500 minus $150,000) as his separate
property, and that the parties would split the remaining $602,500
equally.
¶9 	The commissioner’s oral ruling was later encapsulated in
written findings of fact and conclusions of law and a decree of
divorce, which documents were signed by the assigned district
court judge.
ISSUES AND STANDARDS OF REVIEW
¶10 	Marcus 	now 	appeals, 	and 	he 	challenges 	the 	specific
portions of the commissioner’s ruling that concern allocation of
the value of the House. In particular, he takes issue with the
commissioner’s determination that much of the House’s value
was commingled into the marital estate. And he challenges the
finding that the House was worth $312,500 in 2004.
¶11 	Mona asserts that, because this case comes to us from an
“informal custody trial,” the applicable standard of review is
deferential and the scope of appeal is “steep and constricted.”
Mona is certainly correct that, when parties agree to resolve their
issues through an informal trial, they waive their right to appeal
certain evidentiary issues. See Utah R. Jud. Admin. 4-904(b)(7)
(stating that parties may not appeal from an informal trial on
“grounds that . . . rely upon the Utah Rules of Evidence”). In this
case, Marcus and Mona agreed that they would “not be able
to 	challenge 	any 	of 	the 	documents 	or 	testimony 	that 	was
considered” during the proceeding, and neither party attempts
to 	raise 	any 	evidentiary 	issues 	on 	appeal. 	But 	Mona 	is
incorrect 	when 	she 	asserts 	that 	the 	appellate 	standards 	of
review—on the issues that are appealable—are any different in
appeals from informal trials than they are in other cases. The

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court’s 	ultimate 	ruling 	is 	appealable, 	see 	id. 	(stating 	that 	a
“final order” from an informal trial “may be appealed on any
grounds” other than grounds that “rely upon the Utah Rules of
Evidence”), and will be reviewed under the same appellate
standards of review that are applicable in appeals from formally
tried cases.
¶12 	Mona resists this conclusion by pointing to language in the
parties’ stipulation stating that “[t]he only issue on appeal will be
whether the [c]ourt abused its discretion in reaching its findings
and conclusions.” She argues therefrom that all issues in this
appeal—regardless of the usual standards of review—must be
reviewed for abuse of discretion. We disagree. The form the
parties used to encapsulate their stipulation is a form that—in
keeping with the usual usage of the informal trial procedure—is
designed for custody cases. We thus interpret the form’s reference
to the “abuse of discretion” standard as simply indicating that the
court’s ultimate ruling regarding custody will be reviewed as per
usual: for abuse of discretion. See Lobendahn v. Lobendahn, 2023 UT
App 137, ¶ 18, 540 P.3d 727 (“We review custody determinations
under an abuse of discretion standard, giving the district court
broad 	discretion 	to 	make 	custody 	awards.” 	(quotation
simplified)). We do not interpret the form as indicating that—for
issues that are appealable—the standards of appellate review are
any different in cases coming to us after an informal trial than they
are in cases coming to us in the usual manner.
¶13 	Now that we have determined that the standards of review
in this appeal will be the same as in an appeal from a formally
tried case, we must determine what those standards of review are.
Marcus contends that both of the court’s determinations that he is
here challenging—regarding commingling and the House’s value
in 	2004—are 	conclusions 	of 	law 	properly 	reviewed 	for
correctness. 	Mona, 	on 	the 	other 	hand, 	asserts 	that 	these
determinations are factual and reviewed for abuse of discretion or
clear error. We agree with Mona.

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¶14 	“[District] courts are in the best position to determine
whether property is marital or separate, and we defer to their
findings 	of 	fact 	[in 	this 	regard] 	unless 	clearly 	erroneous.”
Thompson v. Thompson, 2009 UT App 101, ¶ 10, 208 P.3d 539; see
also Lindsey v. Lindsey, 2017 UT App 38, ¶ 26, 392 P.3d 968 (“We
generally defer to a [district] court’s categorization and equitable
distribution of separate property and uphold its determinations
in that regard unless a clear and prejudicial abuse of discretion is
demonstrated.” (quotation simplified)). Thus, we review a district
court’s factual findings in this regard for clear error, and we
review for abuse of discretion its ultimate determination of
whether a particular item is separate or marital property.
¶15 	And this same standard of review also applies to the more
specific question of whether the House was commingled into the
marital estate. See Dahl v. Dahl, 2015 UT 79, ¶ 143, 459 P.3d 276
(reviewing a commingling ruling for abuse of discretion); Oliekan
v. Oliekan, 2006 UT App 405, ¶¶ 18–19, 147 P.3d 464 (same). A
court’s determination that a piece of originally separate property
has been commingled into the marital estate is just a particular
way of determining that the property is marital (rather than
separate) property.
¶16 	Finally, we also apply a deferential standard of review to
Marcus’s challenge to the court’s finding regarding the value of
the House in 2004. See Marroquin v. Marroquin, 2019 UT App 38,
¶ 10, 440 P.3d 757 (“We defer to [a] district court’s findings of
fact related to property valuation and distribution unless they
are clearly erroneous.” (quotation simplified)); see also Rothwell
v. Rothwell, 2023 UT App 50, ¶ 33, 531 P.3d 225 (“A district
court’s 	factual 	determinations 	are 	clearly 	erroneous 	only 	if
they are in conflict with the clear weight of the evidence, or if
this court has a definite and firm conviction that a mistake has
been made.” (quotation simplified)), cert. denied, 537 P.3d 1011
(Utah 2023).

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ANALYSIS
¶17 	We first discuss Marcus’s challenge to the court’s ruling
that much of the House’s value had been commingled into the
marital estate. We then turn to Marcus’s challenge to the court’s
finding that the House was worth $312,500 in 2004.
I. The House: Separate or Marital Property?
¶18 	On the question of whether and to what extent the House
constitutes marital property, we begin by discussing what is at
issue in this appeal and—notably—what is not at issue in this
appeal. Neither party challenges the court’s determination that
the House was originally Marcus’s separate property when title
was placed in his name in 2004. The court awarded Marcus
$162,500, intended to represent the original value of the House in
2004, less the later loan amount. The basis for this award, as we
understand 	it, 	was 	the 	commissioner’s 	(at 	least 	implicit)
determinations that the House was Marcus’s separate property in
2004 and that Marcus is entitled to keep his separate property to
the extent it was not commingled or subject to an equitable
contribution made by Mona. No party challenges that portion of
the commissioner’s ruling.
¶19 	Marcus 	does 	challenge 	two 	other 	aspects 	of 	the
commissioner’s ruling regarding the House’s status as separate or
marital property. First, Marcus challenges the commissioner’s
determination that $150,000 of the original value of the House—
the amount of the December 2004 loan—had been commingled
into the marital estate. Second, Marcus takes issue with the
determination that the appreciation, over time, in the value of
the House became 	commingled into the marital estate. We
discuss these two challenges, in turn, after first setting forth
applicable 	legal 	principles 	regarding 	separate 	property 	and
commingling.

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A. Background Legal Principles
¶20 	One of the tasks courts often face in adjudicating divorce
cases is making an equitable division of the marital estate between
the divorcing spouses. Our supreme court has described this
property-division process as follows:
Before a district court distributes marital assets, it
must 	(1) 	identify 	the 	property 	in 	dispute 	and
determine 	whether 	it 	is 	marital 	or 	separate
property, (2) consider whether there are exceptional
circumstances 	that 	overcome 	the 	general
presumption 	that 	marital 	property 	be 	divided
equally, (3) assign values to each item of marital
property so that a distribution strategy can be
implemented, and (4) distribute the marital assets
consistent with the distribution strategy.
Dahl 	v. 	Dahl, 	2015 	UT 	79, 	¶ 	121, 	459 	P.3d 	276 	(quotation
simplified). Marcus’s first challenge concerns the first step in this
process: assessing whether a particular piece of property—here,
the House—is marital property that belongs to the marital estate
or is instead separate property that belongs to him alone.
¶21 	“Marital 	property 	ordinarily 	includes 	all 	property
acquired during [the] marriage, whenever obtained and from
whatever source derived.” Lindsey v. Lindsey, 2017 UT App 38,
¶ 31, 392 P.3d 968 (quotation simplified). Separate property, on
the other hand, includes each spouse’s “premarital property”—
that is, property owned by one spouse prior to the marriage—as
well as “gifts[] and inheritances” received by a spouse during the
marriage. See id.; see also Mortensen v. Mortensen, 760 P.2d 304, 308
(Utah 1988) (stating that courts should “generally award property
acquired by one spouse by gift and inheritance during the
marriage . . . to that spouse”).

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¶22 	Property determined to be part of the marital estate will be
divided 	equitably—and 	presumptively 	equally—between 	the
divorcing spouses. See Lindsey, 2017 UT App 38, ¶ 32 (“The
presumption is that marital property will be divided equally
. . . .”). But separate property “will not be divided at all,” id., and
will “generally” be awarded, “together with any appreciation or
enhancement of its value,” to the spouse whose separate property
it is, see Mortensen, 760 P.2d at 308; see also Lindsey, 2017 UT App
38, ¶ 32 (“Equity generally requires that each party retain the
separate property he or she brought into the marriage, including
any appreciation thereof.” (quotation simplified)).
¶23 	In some situations, however, property that begins as one
spouse’s separate property can lose its separate identity and
become part of the marital estate. See Mortensen, 760 P.2d at 308;
see also Lindsey, 2017 UT App 38, ¶ 33 (stating that, sometimes,
“circumstances warrant an equitable override of the separate-
property retention rule”). Our case law has identified three such
situations: (1) where “separate property has been commingled”
into the marital estate, Lindsey, 2017 UT App 38, ¶ 33; (2) where
“the other spouse has by his or her efforts or expense contributed
to the enhancement, maintenance, or protection of that property,
thereby acquiring an equitable interest in it,” Mortensen, 760 P.2d
at 308; and (3) “in extraordinary situations when equity so
demands,” Lindsey, 2017 UT App 38, ¶ 33.
¶24 	First, with regard to commingling, one rather obvious
situation in which commingling occurs is where “one spouse has
contributed all or part of the property to the marital estate with
the intent that it become joint property.” See Dahl, 2015 UT 79,
¶ 143. But even short of an outright intended contribution,
property that started out as separate property may be considered
commingled 	if 	it 	becomes 	inextricably 	and 	untraceably
intertwined with marital assets. See id. (“[P]remarital property
may lose its separate character where the parties have inextricably
commingled it with the marital estate . . . .”). Quite important to

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any commingling analysis, then, is whether the property in
question has retained “its separate character.” See id. And this
inquiry often turns on whether the property’s separate identity
can still be traced or accounted for. See Mortensen, 760 P.2d at 307
(stating that property is commingled when it “completely loses its
identity and is not traceable”); see also Pusey v. Pusey, 728 P.2d 117,
119 (Utah 1986) (upholding a district court’s determination that
property was commingled because “it could not trace any assets
to any source”). Indeed, in one case we phrased the relevant
question 	as 	whether 	the 	property 	at 	issue 	“became 	so
commingled that [it] could not be segregated” from the marital
estate, and we determined that it had not, because “the marital
and 	premarital 	interests 	were 	reasonably 	capable 	of 	being
determined” and “it was still possible to trace and separately
identify” the separate property. Oliekan v. Oliekan, 2006 UT App
405, ¶¶ 20–23, 147 P.3d 464. Thus, separate property will be
considered commingled when it has been mixed in with marital
assets to such a degree that it is no longer reasonably possible to
distinguish between the separate and marital property. On the
other hand, if “the marital and premarital interests” are still
“reasonably capable” of being traced and identified, then the
separate property retains its separate nature and will not be
considered commingled. See id.
¶25 	Second, “under the contribution exception, a spouse’s
separate property may be subject to equitable distribution when
the other spouse has by his or her efforts or expense contributed
to the enhancement, maintenance, or protection of that property,
thereby acquiring an equitable interest in it.” Lindsey, 2017 UT
App 38, ¶ 35 (quotation simplified). “This exception may be
satisfied when one spouse brings assets into the marriage and the
other spouse’s prudent investment of those assets substantially
increases their value, or when marital funds are expended or
marital debt is incurred for the benefit of one spouse’s separate
property.” Id. (quotation simplified). “Under such circumstances,
one spouse’s effort or investment may render the other spouse’s

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underlying asset, its appreciated value, or some portion thereof
subject to equitable distribution.” Id.
¶26 	Third, there exists a catch-all exception for situations—not
covered 	by 	either 	of 	the 	first 	two 	exceptions—in 	which
“extraordinary circumstances . . . warrant a departure from the
presumptive rule.” Henshaw v. Henshaw, 2012 UT App 56, ¶ 15,
271 P.3d 837. This exception is rarely applied; we have stated that
the “bar for establishing an extraordinary situation is high,
traditionally 	requiring 	that 	invasion 	of 	a 	spouse’s 	separate
property is the only way to achieve equity.” Lindsey, 2017 UT App
38, ¶ 46 (quotation simplified).
¶27 	During the informal trial, Mona made arguments under
the first two of these exceptions, arguing that—even if the House
was Marcus’s separate property in 2004 when it was gifted to
him—at least part of the House’s value became part of the marital
estate due to commingling or due to the family’s equitable
contribution. The commissioner accepted Mona’s commingling
argument, and therefore opted not to consider whether, or to what
extent, Mona had acquired an equitable interest in the House
through contributions.
B. The $150,000 Loan
¶28 	The first part of the commissioner’s commingling analysis
with which Marcus takes issue is the ruling that $150,000 of the
House’s original value became commingled into the marital
estate. In December 2004, some seven months after the House was
gifted to Marcus, he used the House as collateral for a $150,000
loan, and that loan was fully repaid, over the next ten years, with
marital funds. The commissioner determined that, given these
facts, “the marital estate paid for that portion of the [H]ouse
directly by paying off the mortgage,” and ruled that the amount
of the House’s original value collateralized by the loan ($150,000)
was marital property rather than Marcus’s separate property.

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¶29 	We acknowledge the facial appeal of the commissioner’s
ruling: the fact that the marital estate paid the loan back certainly
makes it look like the estate might have acquired an interest in the
House. But our supreme court has made clear that a separate asset
does not necessarily become marital property simply because a
marital estate pays back a loan drawn from that asset. See Dahl v.
Dahl, 2015 UT 79, ¶¶ 142–145, 459 P.3d 276. At a minimum, more
analysis is required in order to reach that conclusion.
¶30 	In 	Dahl, 	a 	husband 	had 	possessed 	certain 	retirement
accounts (IRAs) “prior to his marriage” that were his “separate
property.” Id. ¶ 142. During the marriage, the husband “withdrew
funds from the IRA[s] to pay off a home equity loan secured by
the marital home and then replenished the funds using a marital
bank account.” Id. The wife contended that, by this action, the
husband had “commingled” the IRAs with marital assets and
thereby “converted [them] to marital property.” Id. ¶¶ 142, 144.
¶31 	Our supreme court rejected the wife’s argument, holding
that the husband’s actions did not cause the IRAs to lose “their
separate identity.” Id. ¶ 144. In the court’s view, the transaction
was “best characterized as a loan from [the husband] to the
marital estate, which was in turn repaid with marital funds.” Id.
On the facts presented in Dahl, there was “nothing . . . suggesting
that [the husband] intended to commingle his IRA funds with the
marital estate.” Id. And the court held that the IRAs “did not
become so inextricably commingled into the marital estate that
the district court was incapable of tracing [them].” Id. (quotation
simplified). In summary, the court noted that the IRAs did not
lose their “separate identity simply because [the husband] made
a loan from [the IRAs] to pay off a home equity loan.” Id. ¶ 145.
¶32 	The lesson of Dahl, as relevant here, is that when one
spouse uses his or her separate property to facilitate a loan to the
marital estate, the proceeds from that loan are used to benefit the
marital estate, and the marital estate pays the loan back with

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marital funds, the separate property used to facilitate the loan
does not, simply by virtue of the loan, become commingled into
the marital estate.
¶33 	Marcus asserts that Dahl is materially indistinguishable
from this case. As he sees it, he facilitated a loan to the marital
estate using his own separate property—the House—as collateral,
and the marital estate was obligated to pay that loan back just like
it would have needed to pay off a loan collateralized in any other
way. He asserts that—just like the transaction in Dahl—nothing
about 	this 	transaction 	indicates 	any 	intent 	on 	his 	part 	to
commingle the House with the marital estate. And he notes—
correctly—that this loan did not render a factfinder incapable of
tracing his separate property. We find Marcus’s arguments at
least potentially persuasive, and we note that Mona (in her
appellate brief) did not cite Dahl and made no effort to rebut
Marcus’s argument that Dahl is controlling here.
¶34 	We agree with Marcus that the commissioner’s analysis is
at odds with Dahl.2 The commissioner’s analysis on this point was
quite brief, and simply assumed that, because the marital estate
repaid the $150,000 loan amount, it had “paid for that portion of
the [H]ouse directly.” As noted, it does not necessarily follow,
simply from the fact that the marital estate repaid the loan, that
2. In fairness to the commissioner, Marcus did not cite Dahl during
the informal trial. But this does not present a preservation
problem, because litigants are permitted to cite new authority for
the first time on appeal to support arguments regarding issues
properly raised below. See Patterson v. Patterson, 2011 UT 68, ¶ 18,
266 P.3d 828 (“[W]e routinely consider new authority relevant to
issues that have properly been preserved . . . .”). In this instance,
the parties raised the relevant issue at the informal trial—whether
$150,000 of the House’s original value was commingled into the
marital estate—and are therefore entitled to bring new authority
to our attention on appeal bearing on this preserved issue.

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the asset that facilitated the loan—here, the House—became
commingled into the marital estate. See id. ¶ 144.
¶35 	The question of whether repayment of the loan by the
marital estate resulted in commingling turns on whether the
proceeds of the loan were used for marital-estate purposes
unrelated to the House or were, instead, used to increase the value
of the House. If the proceeds were used—as they were in Dahl—
entirely 	for 	marital-estate 	purposes 	unrelated 	to 	the 	asset
leveraged for the loan, then Marcus is correct that the situation
here would be materially indistinguishable from Dahl, and the
transaction would be “best characterized as a loan . . . to the
marital estate” facilitated by Marcus’s separate property. See id.
On the other hand, if the loan proceeds were used to improve the
House, 	the 	marital 	estate’s 	repayment 	of 	that 	loan 	might
accurately be said to have resulted in the marital estate “[paying]
for that portion of the [H]ouse directly,” a situation that might
support a determination that commingling (or, alternatively,
acquisition of an equitable interest) had occurred.
¶36 	On the question of what the loan proceeds were used for,
the commissioner made no findings. Marcus testified that the loan
proceeds were spent not on the House (or on any other personal
endeavors of Marcus) but on marital things, such as medical and
credit card bills, other unspecified “investments,” and a payment
on the couple’s “cabin lot.” But neither in the oral ruling made at
the conclusion of the informal trial nor in the written ruling issued
thereafter did the commissioner make any specific findings about
either the credibility of Marcus’s testimony on this point or about
whether any of the loan proceeds were spent on the House.3
3. At the conclusion of the informal trial, the commissioner stated
that some of the loan proceeds were “used to pay some medical
bills for” Mona. It is unclear from the record whether this
(continued…)

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20220583-CA 	16 	2024 UT App 93
¶37 	In 	the 	end, 	we 	view 	the 	commissioner’s 	analysis 	as
incomplete. 	Because 	the 	reason 	the 	commissioner 	gave 	for
determining that the loan amount had been commingled does not
necessarily 	support 	that 	conclusion, 	and 	because 	the
commissioner did not make certain factual findings necessary to
complete 	the 	analysis, 	we 	must 	reverse 	the 	commissioner’s
determination that $150,000 of the House’s original value was
commingled into the marital estate, and we remand the matter to
the district court for further proceedings on this point.
C. The House’s Appreciation
¶38 	The 	second 	part 	of 	the 	commissioner’s 	commingling
analysis with which Marcus takes issue is the ruling that all of the
House’s appreciation since 2004—an amount the commissioner
determined to be $452,500 ($765,000 minus $312,500)—was no
longer 	Marcus’s 	separate 	property 	because 	it 	had 	been
commingled into the marital estate. As support for this ruling, the
commissioner 	cited 	(a) 	the 	homeowners 	insurance 	policies
acquired before Marcus owned the House that listed both Marcus
and Mona as “owners,” (b) Mona’s testimony that she was
responsible for maintaining the House and its landscaping, and
(c) the fact that Mona’s mother had paid $13,000 toward “a
mother-in-law apartment” in the late 1990s. Even applying a
deferential standard of review, we agree with Marcus that the
commissioner committed an abuse of discretion in so ruling.
¶39 	We begin our analysis by repeating the long-established
legal principle that, ordinarily, appreciation on separate property
belongs not to the marital estate but, rather, to the spouse whose
statement constituted an oral factual finding or merely a musing
on the part of the commissioner, and no such finding appears in
the written ruling. In any event, we are unaware of any statements
or findings, written or oral, made by the commissioner about
whether any of the loan proceeds were used on the House.

Thorup v. Thorup
20220583-CA 	17 	2024 UT App 93
separate property it is. Mortensen v. Mortensen, 760 P.2d 304, 308
(Utah 1988) (stating that separate property, “together with any
appreciation or enhancement of its value,” belongs to the separate
spouse); Keyes v. Keyes, 2015 UT App 114, ¶ 28, 351 P.3d 90 (“In
most cases, equity requires that each party retain the separate
property that he or she brought into the marriage, including any
appreciation of the separate property.” (quotation simplified));
Thompson v. Thompson, 2009 UT App 101, ¶ 12, 208 P.3d 539 (“An
award of separate property includes its appreciation during the
marriage.”); Burt v. Burt, 799 P.2d 1166, 1169 (Utah Ct. App. 1990)
(“Inherited or donated property, as well as its appreciated value,
is generally regarded as separate from the marital estate and
hence is left with the receiving spouse in a property division
incident to divorce.”).
¶40 	This general rule—that a spouse should receive his or her
separate 	property, 	together 	with 	any 	appreciation—may 	be
varied on the basis of commingling, but only when it is clear that
the spouse intended to contribute the property to the marital
estate, or when it becomes functionally impossible to trace or
account for the separateness of the spouse’s property. See Oliekan
v. Oliekan, 2006 UT App 405, ¶¶ 20–23, 147 P.3d 464 (stating that
the question in commingling cases is whether the property
“became so commingled that [it] could not be segregated” from
the marital estate, and determining that commingling was not
present 	because 	“the 	marital 	and 	premarital 	interests 	were
reasonably capable of being determined” and because “it was still
possible to trace and separately identify” the separate property);
see also Dahl, 2015 UT 79, ¶ 143 (“[P]remarital property may lose
its 	separate 	character 	where 	the 	parties 	have 	inextricably
commingled it with the marital estate, or where one spouse has
contributed all or part of the property to the marital estate with
the intent that it become joint property.”).
¶41 	Commingling 	occurs 	most 	commonly 	with 	money,
because 	dollars 	are 	fungible 	and, 	when 	separate 	money 	is

Thorup v. Thorup
20220583-CA 	18 	2024 UT App 93
deposited 	into 	the 	same 	account 	as 	marital 	money, 	it 	can
become difficult to tell which dollar is which. See, e.g., Pusey v.
Pusey, 728 P.2d 117, 119 (Utah 1986) (affirming a district court’s
finding 	“that 	throughout 	the 	marriage 	[the 	husband] 	had
commingled corporate and personal funds so that [the court]
could not trace any assets to any source”). Yet even money will
not be considered commingled if the separate property funds can
be identified and traced. See, e.g., Oliekan, 2006 UT App 405, ¶ 23
(affirming a district court’s determination that no commingling
had occurred because “it was still possible to trace and separately
identify the funds” at issue); accord Arnason v. Arnason, 2002 UT
App 243U, para. 2.
¶42 	Real property is easier to trace than money, and it is
therefore perhaps not as common for commingling to occur
with regard to real property as it is with money. Cf. Dahl, 2015
UT 79, ¶ 146 (“A spouse can maintain the separate identity
of premarital [real] property by utilizing section 1031 exchanges
to avoid commingling separate property with marital property.”).
But it is at least conceivable that separate real property—or at
least the proceeds therefrom—can become commingled into a
marital estate. For instance, in one case we concluded that,
where proceeds from the sale of separate property (including
real 	property) 	had 	been 	“deposit[ed] 	into 	the 	parties’ 	joint
accounts” and thereby lost its separate identity, commingling
had occurred. Dunn v. Dunn, 802 P.2d 1314, 1321 (Utah Ct.
App. 	1990). 	And 	in 	other 	cases, 	we 	have 	observed 	that,
where significant or substantial marital assets are invested to
support, 	maintain, 	or 	improve 	separate 	real 	property,
commingling may have taken place. Keiter v. Keiter, 2010 UT App
169, ¶ 23, 235 P.3d 782 (stating that “expending marital funds
toward otherwise separate real estate supports a determination of
commingling that may convert separate property into marital
property”); Schaumberg v. Schaumberg, 875 P.2d 598, 603 (Utah Ct.
App. 	1994) 	(affirming 	a 	district 	court’s 	determination 	that
commingling 	of 	the 	“appreciated 	portion” 	of 	a 	husband’s

Thorup v. Thorup
20220583-CA 	19 	2024 UT App 93
separate real property had occurred where the parties had “used
substantial 	marital 	funds 	to 	maintain 	and 	augment” 	the
property).
¶43 	In this case, however, the House was never sold, and
therefore no proceeds from any sale were ever deposited into a
marital account. And there was no evidence presented that the
parties 	invested 	significant 	sums 	of 	marital 	money 	into
supporting, maintaining, or otherwise improving the House.
Here, tracing the separate nature of the House, including the
appreciation in its value, is fairly obvious, and we see no evidence
indicating that the House ever lost its separate identity.
¶44 	In 	particular, 	we 	find 	the 	evidence 	upon 	which 	the
commissioner relied unpersuasive and entirely unsupportive of a
determination that all appreciation of the House after 2004 was
commingled into the marital estate. Two of the three items upon
which the commissioner relied—that both Marcus and Mona
appeared as “owners” on homeowners insurance policies, and
that Mona’s mother paid $13,000—occurred prior to 2004, before
Marcus even owned the House. These items therefore have
extremely limited value in the analysis, and they simply do not
point to any commingling of post-2004 appreciation.
¶45 	The other item upon which the commissioner relied—the
fact that Mona had been involved in some of the maintenance
of the House, especially the landscaping—is likewise insufficient
to support a determination that the entirety of the House’s
appreciation 	was 	commingled 	into 	the 	marital 	estate. 	As
noted above, the investment of substantial marital assets into
separate real property can support a determination that the
separate property was commingled. See Keiter, 2010 UT App 169,
¶ 23; Schaumberg, 875 P.2d at 603. But here, no such evidence
was presented; Mona did not offer evidence of any specific
monetary contributions, nor did she attempt to provide many
particulars 	about 	the 	nature 	of 	her 	landscaping 	and 	other

Thorup v. Thorup
20220583-CA 	20 	2024 UT App 93
contributions.4 One spouse’s residence at, and assistance with the
day-to-day maintenance of, the other spouse’s separate real
property will not usually be enough to render the entirety of that
property’s 	appreciation 	commingled 	into 	the 	marital 	estate.
Under 	the 	circumstances 	presented 	here, 	we 	conclude 	that
Mona’s rather non-specific contributions to maintenance and
landscaping are insufficient to support a determination that the
entirety of the House’s appreciation was commingled into the
marital estate.
¶46 	That is not to say that such contributions are irrelevant to
the ultimate separate-or-marital-property analysis. As noted,
Mona also made an argument, at the informal trial, that she had
made an equitable contribution to the value of the House that
should be recognized under the contribution exception to the
general rule that separate property goes to the individual spouse.
While Mona’s evidence is insufficient to support a determination
that the entirety of the House’s appreciation was commingled into
the marital estate, such evidence might be sufficient to support a
determination that Mona made an equitable contribution to the
House 	that 	ought 	to 	be 	quantified 	and 	recognized 	in 	the
distribution of marital property.
4. The best evidence of Mona’s contributions appears to be found
in her answer to a written interrogatory from Marcus that asked
her to “detail” all her contributions to the House. In that answer,
she stated generally that she “maintained and upkept” the House
and “was in charge of maintaining the yard.” She also described
other remodeling and maintenance activities, such as helping to
repaint, retile, and redecorate various rooms in the House. But she
made 	no 	effort—whether 	in 	that 	interrogatory 	response 	or
otherwise—to quantify her efforts in dollars, and she did not hire
an appraisal expert to assess any increase in value to the House
that her efforts might have brought about or to rebut Marcus’s
appraisal expert’s conclusions in that regard.

Thorup v. Thorup
20220583-CA 	21 	2024 UT App 93
¶47 	Accordingly, 	we 	conclude 	that 	the 	commissioner
committed an abuse of discretion in determining, on this record,
that 	the 	entirety 	of 	the 	House’s 	appreciation 	had 	been
commingled into the marital estate, and we therefore reverse that
determination. We remand the matter, however, so that the
district court might have an opportunity to consider Mona’s
alternative argument—not reached by the commissioner—that
she made an equitable contribution to the value of the House that
should be considered in the distribution of the marital estate.
II. The House’s 2004 Value
¶48 	Marcus also challenges the court’s finding that the value of
the House, when it was gifted to him in 2004, was $312,500.
Marcus argues that the House’s value was actually $445,000—the
amount his father’s construction company spent to build it. On
this record, however, we conclude that the court’s finding is
supported by competent evidence and that the commissioner
therefore did not commit clear error in making it.
¶49 	When a court is asked to value real property, it may do so
in any one of several ways, depending on the evidence presented.
Certainly, one way to value a house is to assess how much it cost
to build it. See Carter v. Sorenson, 2004 UT 33, ¶ 2, 90 P.3d 637
(referring to the “traditional appraisal methods” as “the cost
approach, 	the 	income 	approach, 	and 	the 	sales 	comparison
approach”). But more commonly, appraisers value residential real
property using a “comparable sales” approach, in which they
attempt to “locate and analyze sales of ‘comparable’ properties . . .
between a willing buyer and a willing seller in which the sale price
is determined by market forces.” See Utah Dep’t of Transp. v.
Admiral Beverage Corp., 2011 UT 62, ¶ 40, 275 P.3d 208.
¶50 	During the informal trial, Marcus presented evidence that
his father’s construction company spent $445,000 to build the
House in the 1990s. Had that been the only evidence presented at

Thorup v. Thorup
20220583-CA 	22 	2024 UT App 93
trial, Marcus may have a credible argument that the court
committed clear error by not adopting that methodology in
assessing the House’s 2004 value. But that was not the only
evidence presented at trial. Marcus also presented an appraisal of
the House, as of May 2004, that applied a comparable-sales
methodology; the first draft of that appraisal valued the House at
$285,000, and an “amended draft” valued it at $340,000. The court
found, based on this evidence, that the best indication of the value
of the House in 2004 was an “averag[e] of the two values proposed
by” Marcus’s appraiser, which is $312,500.
¶51 	This finding is amply supported by evidence in the record
and is therefore not clearly erroneous. See Kimball v. Kimball, 2009
UT App 233, ¶ 20 n.5, 217 P.3d 733 (“The pill that is hard for many
appellants to swallow is that if there is evidence supporting a
finding, absent a legal problem—a fatal flaw—with that evidence,
the finding will stand, even though there is ample record evidence
that 	would 	have 	supported 	contrary 	findings.” 	(quotation
simplified)). We therefore reject Marcus’s challenge to the court’s
finding that the House was worth $312,500 when it was gifted to
him in 2004.
CONCLUSION
¶52 	We reject Marcus’s challenge to the court’s factual finding
regarding the value of the House in 2004. But we sustain Marcus’s
challenges 	to 	the 	court’s 	commingling 	determination, 	and
specifically to its rulings that (a) $150,000 of the House’s original
value was commingled and (b) the entirety of the House’s post-
2004 appreciation was commingled. We therefore reverse the
court’s equity allocation order, and we remand the case to the
district court for further proceedings, consistent with this opinion,
regarding the use to which the parties put the 2004 loan proceeds
and regarding Mona’s claim to an equitable interest in the
appreciation of the House under the contribution exception.