What’s the issue?

It is often said that good fences make good neighbours.[1]  But condominium living often raises one key question: where does your unit end, and the common property begin?  This boundary is critical because it determines who – owner or condominium corporation – is responsible for potential costly repairs and upgrades.

The Alberta Court of Appeal’s recent decision in Aubin v Condominium Plan No 862 2917 (“Aubin”) offers new guidance, with implications for hundreds of condo plans across the province.

What is the Aubin case about?

This case involved a unit owner who owned a ground-floor unit in a high-rise condominium building.  The unit itself shared a common wall with the condominium’s common property lounge, which was used for board meetings and social functions, as may be scheduled by any unit owner. 

In 2019, the unit owner brought a claim against her condominium corporation, alleging that the condominium corporation had a duty to improve the sound transference between the common area lounge and her unit, on the other side of the wall.  The issue, as explained by the unit owner in her own evidence, was that she could hear noise coming from the lounge when it was in use, and that the noise was allegedly interrupting her daily life.

What are condominiums in legal terms?

Condominiums can be many things: 

  • apartment-style high-rise buildings;
  • commercial warehouses;
  • townhouses; and even
  • bare parcels of land.  

Condominiums are not a specific type of construction, nor are they just a form of collective living.  Condominiums are in actual fact a form of collective property ownership.  That is, they are a legal construct to facilitate the shared ownership of real property.  Through that construct, unit owners own and are responsible for their private units.  Like any property owner, unit owners must maintain their unit, comply with the applicable rules and community standards that govern their community, and are liable when they cause damage to neighbouring property owners. 

Condominium unit owners also own a proportionate share of the common property in their condominium.  A “condominium corporation” is the statutory body that comes into being when a condominium plan is registered to manage the maintenance of the collective common property interests of all of the owners. 

Indeed, the condominium context creates a further layer of complexity, given the competing interests that must all be balanced for peaceful co-existence and shared property ownership.  The responsibility of balancing the private and communal interests of the unit owners falls to the condominium’s elected board of directors, who are generally entitled to deference in the exercise of their discretion in managing the shared property of all unit owners in their collective best interests to, hopefully, achieve the greatest good for the greatest number.[2]  On this point, when reviewing a condominium board’s decision, a court’s first question is usually to ask whether the directors acted honestly and in good faith and exercised the care, diligence and skill that a reasonably prudent person would exercise in comparable circumstances.[3]

What was at stake in the Aubin case?

In Aubin, the building was built in approximately 1973.  Neither the condominium corporation nor the unit owner played any part in the construction and design of the wall and there was no evidence that the wall was not otherwise structurally sound or had ever been renovated or altered since the time of the building’s original construction.  The Court had to decide who is responsible for the wall: the owner or the condominium corporation?

How does the Condominium Property Act define boundaries?

Defining the boundary became critical to determining who, as between the unit owner and the condominium corporation, was responsible for improving the sound transference that was noted to be below applicable building code standards.

Section 8(1)(f) of the Condominium Property Act (the “CPA”) specifically requires that every condominium plan in Alberta must contain a description setting the boundary between the units and common property.  Appreciating that condominium plans are drafted by land surveyors, and not lawyers, s. 9 of the CPA sets certain default boundaries to clarify the legal boundary between units and common property.  This facilitates a purposive interpretation of the condominium plan documents, akin to the interpretation of municipal planning documents and statutes more broadly.

In this regard, the statutory default under s. 9(1) provides:

9(1)  Unless otherwise stipulated in the condominium plan, if

(a)    a boundary of a unit is described by reference to a floor, wall or ceiling, or

(b)    a wall located within a unit is a load bearing wall,

the only portion of that floor, wall or ceiling, as the case may be, that forms part of the unit is the finishing material that is in the interior of that unit, including any lath and plaster, panelling, gypsum board, panels, flooring material or coverings or any other material that is attached, laid, glued or applied to the floor, wall or ceiling, as the case may be.

[emphasis added]

By operation of the statutory default under s. 9, therefore, the drywall on the interior of a unit is part of the owner’s private unit, whereas the interior wall studs and building structure are common property.  This avoids the historic approach where the boundary was considered to be the centre-point of the shared floor, wall, or ceiling, which resulted in individual owners bearing some responsibility for building structural components located within these components and beyond the surface finishings.  

The notation in the condominium plan documents in Aubin, as required pursuant to s. 8(1)(f), provided as follows:

The boundary of any unit with the common property is the undecorated interior surface of the unit floor, wall, or ceiling as the case may be.

As readers familiar with condominiums will appreciate, this wording is typical of hundreds of condominium plans throughout Alberta and has become a sort of historic industry standard for many surveyors who draft condominium plans.[4]  What might also be noted is that this wording is not an exact copy of s. 9.  In this regard, the Court noted:

[31]        … the condominium plan stipulates the unit boundaries with sufficient specificity to displace the default position in s 9(1). The condominium plan provides “the boundary of any unit with common property is the undecorated interior surface of the unit floor, wall, or ceiling as the case may be” [emphasis added]. This is distinct from how unit boundaries are described in s 9(1), which says, “the finishing material that is in the interior of that unit, including any lathe and plaster, panelling, gypsum board, panels, flooring material or coverings or any other material that is attached, laid, glued or applied to the floor, wall or ceiling, as the case may be” [emphasis added].

[32]           The wording of each provision is substantially different. … The default provisions in s 9(1) treat finishing material, such as drywall, as part of the unit but the condominium plan treats only the decoration on that finishing material, for example, paint or wallpaper, as part of the unit. There is no ambiguity. The terms are plain, and their meaning is obvious. In this case, the entirety of the wall separating the appellant’s unit from the lounge, save for any decoration on the surface in the appellant’s unit, is common property and the respondent is responsible for it.[5]

[emphasis in original]

In reaching this conclusion, the Court of Appeal held that there was a fundamental distinction between the language of the condominium plan and the statutory default under s. 9(1).  Taken literally, and applying the specifics of the condominium plan versus the statutory default, the Court found that the difference in the language was material as the plan documents stipulated something other than the statutory default by virtue simply of the difference in language of the plan compared to that of the CPA. 

What did the Court decide in Aubin?

The condominium plan in Aubin used the phrase “undecorated interior surface” instead of the CPA’s “unfinished interior surface.” The Court ruled that this subtle difference meant the entire wall, including the drywall, was common property. In other words, the condo corporation, not the owner, was responsible. Given the ubiquitous language of the plan documents in issue in this case, this distinction can be expected to be found in the condominium plans of hundreds of condominiums across Alberta. 

What are the potential legal implications for condo owners and administrators?

The Court of Appeal ostensibly arrived at this conclusion by applying statutory interpretation principles to the notations on the plan, noting that the interpretation of condominium plans is an exercise analogous to statutory interpretation.  Specifically, a condominium plan must be interpreted:

  • in its entire context;
  • in its grammatical and ordinary sense; and
  • in harmony with the purpose of the CPA and the intention of the legislature.[6] 

How does the doctrine of absurdity apply?

With respect to statutory interpretation, the Supreme Court of Canada also relies on the doctrine of absurdity, which holds that a literal interpretation of statutory words “…can be considered absurd if it leads to ridiculous or frivolous consequences, if it is extremely unreasonable or inequitable, if it is illogical or incoherent, or if it is incompatible with other provisions or with the object of the legislative enactment.”[7] 

Together with the absurdity doctrine, the Supreme Court has also emphasized that statutory interpretation must always proceed according to the text, context, and purpose of the legislation, reminding lower courts that statutory interpretation is centered on the intent of the legislature at the time of enactment and that courts are bound to give effect to that intent.[8]  Interpretations that are consistent with or promote legislative purpose should be adopted, while interpretations that defeat or undermine legislative purpose should be avoided.  This process may also be referred to as the “pragmatic method” of interpretation, which is based on consideration of the effects of a statute, or the effects of a given interpretation of it.[9]  In other words, courts aim to interpret provisions pragmatically, considering the real-world effects of competing interpretations.

What about municipal and planning documents?

Condominium plans are often compared to municipal planning documents because:

  • both are drafted by non-lawyers (surveyors, planners) but bind property owners;
  • both must be interpreted purposively and harmoniously; and
  • courts grant deference to local authorities and boards in applying them.

This analogy reinforces the courts’ view that condo plans, like zoning bylaws, are subordinate enactments requiring careful interpretation.[10]  In this regard, too, the Court of Appeal has recognized that planning documents are neither written by lawyers, nor written for lawyers to administer, but are rather prepared by land surveyors and municipal planners for the local authorities and specialized administrative bodies to administer, who are owed deference in their decisions when interpreting and applying their own planning documents.[11]

Condominium plans, like municipal planning documents more broadly, are akin to subordinate enactments, passed by and under the statutory authority of the CPA in respect of a specific parcel of condominiumized land.  When interpreting such subordinate enactments, courts must also consider the greater legislative milieu that informs the scheme and interpret the provisions in a manner that maximizes the purposive effect of related provisions and avoids internal inconsistencies that may render other provisions meaningless.[12]

Why is Aubin difficult to reconcile with prior law?

When viewed in this light, with the applicable interpretation principles in mind, it is difficult to reconcile the Court’s recent decision in Aubin with the provisions of s. 8 and s. 9 of the CPA. 

In accordance with s. 8(1)(f), every condominium plan must stipulate the boundary between the units and the common property. 

Recognizing that condominium plans are drafted by land surveyors, not lawyers, s. 9 of the CPA goes on to provide for certain default boundaries to aide in interpreting condominium plans. 

Based on the Court of Appeal’s ruling in Aubin, if condominium plans are to be interpreted literally, with no reference to the statutory defaults whatsoever, and given that every condominium plan must specifically stipulate the boundary between units and the common property, it is difficult to see what the purpose of the statutory default in exactly the same regard under s. 9 might be. 

The risk is that s. 9 will be rendered meaningless by operation of the interpretation of a subordinate document.  This, too, is somewhat at odds with the Court’s previous approach to the interpretation of s. 9 and condominium plans. 

For example, in its decision in Alberta Residential Corporation v Certain Lloyd’s Underwriters, the Court of Appeal dealt with a similar issue that involved the exact same, ubiquitous language on the condominium plan as in Aubin.  In the Lloyd’s Underwriters decision, though, the Court rejected the insurer’s argument that “undecorated” (the wording of the condominium plan) and “unfinished” (the wording of s. 9) made any material difference to the constituent parts of the unit for insurance purposes for which the insurer was obligated to repair. 

While not specifically an insurance case and while the dispute in Lloyd’s Underwriters dealt with the definition of a unit rather than strictly the boundary, Aubin arguably stands somewhat at odds with the Court’s historic approach to these issues.

Did the Court introduce equity principles?

Yes. Another aspect of the Aubin decision that bears noting is the introduction of equity to the interpretation of technical planning documents and the allocation of repair and maintenance obligations more broadly. 

In Aubin, the Court of Appeal found that it was not enough for the condominium board to treat the unit owner equally under the bylaws, in that the owner is not specifically singled out, but condominium boards in such cases must also treat owners equitably, and ensure an individual owner’s concerns are fairly considered. This includes recognizing the unique circumstances of an owner’s individual unit.[13]

What is unusual about this is that the Court of Appeal’s own seminal decisions in condominium law preclude the application of equitable principles in the interpretation and application of technical condominium documents.  This marks a shift because:

  • Historically, courts were not permitted to impose what they consider to be fair on a case-by-case basis in a condominium; and
  • The CPA is designed to provide certainty and achieve fairness by enabling all owners to rely on the relative certainty of the allocation of rights and responsibilities in a given condominium corporation, regardless of the whims of a board or its views regarding other aspects of fairness.[14]

Inherent in the choices people make and the prices they pay when they buy real property, there will always be an accounting of the differences between different pieces of real property that people choose to buy.  Owners who purchases a less desirable unit, for instance, cannot demand that the other unit owners pool their resources to improve the unit owner’s own property, when they themselves did not pay for such value. This is as true in purchasing condominium units as with any other real property.  The introduction of equity considerations not just into exercises of discretion, but into the technical and strict requirements to maintain property will likely have to be further clarified by the courts, given the limited resources of condominium corporations and the competing interests of all of their unit owners, which must necessarily be considered.  

What should condo owners and administrators do after Aubin?

Until the relationship between the statutory default boundary and the notations on condominium plans (which, as noted, are mandated by law and must be included in all condominium plans) has been further clarified by the courts, the boundary defined by s. 9 would appear to have so little practical impact that it is almost meaningless, given that every condominium plan must specifically stipulate the unit boundaries.[15]  Being drafted by land surveyors, it is inherent in the nature of condominium plans that there will be variation in the drafting of these notations defining unit boundaries. 

Based on the Court of Appeal’s decision in Aubin, it appears that it will inevitably be the literal wording of the condominium plan documents that governs, and where there is any variation in the drafting that differs from the statutory default (which, as noted, is almost a given) then that will be taken as an intention to vary the default. 

The practical impact of this is:

  • An expansion of common property: Many features previously thought to belong to owners are now considered part of the condominium corporation’s responsibility.
  • Uncertainty about statutory boundaries: The default rules under the CPA cannot be assumed to apply if the condominium plan uses different wording. In such cases, the plan wording prevails.
  • Reclassification of unit finishes: Interior elements such as drywall, ceiling finishes (e.g., popcorn ceilings), and non-decorative floor coverings (e.g., soundproofing underlay) are now to be treated as common property where condominium plans contain wording similar to that in Aubin. 
  • Equitable treatment: The Court has firmly held that in interpreting and applying their own plan documents and the shared responsibilities as between owners and condominium corporations, notwithstanding the broad applicability of these documents across all unit owners, condominium boards must nonetheless strive to ensure that owners are individually treated equitably, and not simply subject to equal treatment under the condominium plans and bylaws. 

Condominium corporations bear the obligation to maintain the common property and investigate and remediate deficiencies.  In exercising the condominium corporation’s maintenance obligations, as well, boards will have to ensure that they treat each and every owner, with all of their individual and potentially conflicting interests, equitably.  It is no longer sufficient to apply the same rules equally to all unit owners. 

In meeting their obligations to maintain the common property and treat owners equitably under the plan documents and bylaws, condominium boards should be mindful that the extent of the common property for which they are responsible may not be obvious and they must treat every request or complaint by a unit owner equitably, and search to find resolution.  Following Aubin, condominium boards would now be well advised to carefully evaluate their condominium plan to determine whether there is more common property in any given situation than may at first meet the eye.   

Conclusion

Condo law is evolving, and the responsibilities of owners and boards are shifting.  Aubin expands what counts as common property and increases the obligations of condominium corporations.  

Do not wait until a dispute arises. If you are a condo board member, property manager, or unit owner, our Condominium & Strata Group can help you interpret your plan, clarify responsibilities, and resolve disputes effectively.

Contact our team today to schedule a consultation or subscribe to our newsletters for ongoing legal updates.

[1] Based on the 1914 poem “Mending Wall” by Robert Frost.

[2] 934859 Alberta Inc. v. Condominium Corporation No. 0312180, 2007 ABQB 640 at paras. 54-55; Anderson v. Owners: condominium plan no. 99SA34021, 2010 SKQB 53 at paras. 23-24; Maverick Equities Inc. v. Condominium Plan No. 942 2336, 2010 ABQB 179 at paras. 44-46; Condominium Corporation No 0723447 v Anders, 2016 ABQB 656, at para. 31.

[3] 3716724 Canada Inc. v. Carleton Condominium Corporation No. 375, 2016 ONCA 650, at para. 53.

[4] See, for example, the Court of Appeal decision in Alberta Residential Corporation v Certain Lloyd’s Underwriters, 2015 ABCA 195, where the Alberta Court of Appeal dealt with an insurance claim involving exactly the same notation in the condominium plan as the one in Aubin.

[5] Aubin v Condominium Plan No 862 2917,2025 ABCA 248, at paras. 31-32.

[6] Rizzo & Rizzo Shoes Ltd. (Re), [1998] 1 SCR 27, at para. 21.

[7] Ibid at para. 27.

[8] Telus Communications Inc. v. Federation of Canadian Municipalities, 2025 SCC 15, at para. 32.

[9] Paragon Capital Corporation Ltd v Starke Dominion Ltd, 2020 ABCA 216, at paras 37-41, citing Pierre-Andre Côté in his text “The Interpretation of Legislation in Canada”, 4th ed (Carswell, 2011) at 469.

[10] Rossdale Community League v Edmonton (City), 2017 ABCA 90, at para. 11.

[11] McCauley Community League v. Edmonton (City), 2012 ABCA 314, at paras. 28 and 32.

[12] Christenson v Kelly, 2025 ABKB 157, at para. 51, citing Cameron Hutchison, The Modern Principle of Statutory Interpretation, 2nd ed (Toronto: LexisNexis, 2022) at 70 and Ruth Sullivan & Elmer A Driedger, Sullivan and Driedger on the Construction of Statutes, 4th ed (Markham, ON: Butterworths, 2002) at 149-50.

[13] Aubin, supra note 5, at para. 38.

[14] Condominium Plan No. 8222909 v. Francis, 2003 ABCA 234, at para. 32.

[15] Section 9 provides particular provisions for doors and windows, which Aubin did not deal with, as it dealt with a wall specifically.  Whether Aubin will have any bearing on doors and windows is yet to be seen.