When Conduct Overrides Clear Terms: The Dangers of Implied Modifications in Lease Agreements

In Kiburu v Boma Mart Ltd & 2 others (Civil Appeal E628 of 2021) [2024] judgment by the High Court, the issue of whether a party’s conduct can override the clear and unambiguous terms of a written lease agreement was front and center. This case, an appeal arising from Civil Suit No. 9519 of 2019, offers valuable insights into how courts should approach the doctrine of conduct when interpreting contractual agreements. The court was tasked with determining whether the conduct of the parties in a lease agreement could alter provisions expressly stated in the contract, specifically with regard to tenant improvements to the leased premises. The decision has important implications for lease agreements and the enforcement of their terms.

Background: A Dispute Over Rent and Renovations

The dispute in this case stemmed from a lease agreement between the appellant (landlord) and the 1st respondent (tenant), wherein the tenant was leasing part of the landlord’s property. Tensions arose when the tenant carried out improvements to the leased premises without seeking or receiving prior written consent from the landlord, as required by the terms of the lease.

The tenant then sought to offset the cost of these renovations against rent arrears, a request the trial court initially entertained. The appellant, however, disputed this arrangement, emphasizing that the lease agreement prohibited such alterations without prior written approval. Furthermore, the appellant argued that the renovations became the property of the landlord at the end of the lease term, as stipulated in the agreement.

Doctrine of Conduct: A Problematic Ruling

The trial court ruled in favor of the tenant, invoking the doctrine of conduct to suggest that the landlord had implicitly consented to the renovations, despite the lack of written approval. The court observed that the landlord had not objected to the renovations during their execution and thus allowed the tenant to offset the cost of the renovations against the rent arrears.

However, this ruling overlooked a critical point: the lease agreement was clear and explicit in its terms regarding tenant improvements. The contract required written consent for any alterations, and any unauthorized modifications were to become the property of the landlord without compensation. The trial court’s reliance on conduct to override the express terms of the lease was problematic and led to a flawed judgment.

Legal Precedent and Contractual Integrity

In appealing the decision, the appellant cited the well-established legal principle that a court cannot rewrite a contract between the parties. As noted in the case of National Bank of Kenya Ltd v Pipeplastic Samkolit (K) Ltd & Another (2001), parties are bound by the terms of their contract unless there is evidence of coercion, fraud, or undue influence. In this case, the lease agreement had no provisions that allowed for an alteration based on implied consent. The court of appeal agreed, emphasizing that the written terms of the lease should prevail over any unspoken assumptions about the landlord’s approval of the renovations.

The Court of Appeal’s Finding

The High Court’s appeal judgment set aside the trial court’s ruling, reinstating the original terms of the lease. The court ruled that the tenant’s failure to seek written consent for the renovations constituted a breach of the lease agreement. Furthermore, it emphasized that such conduct could not modify the express contractual provisions. The tenant was required to restore the premises to their original condition, and the appeal was allowed in favor of the appellant’s counterclaim for unpaid rent.

Key Takeaways for Lease Agreements

This case serves as an important reminder for landlords and tenants alike that written agreements should be strictly adhered to. Courts will typically not allow a party’s conduct to override clear terms in a contract, especially in the absence of express provisions permitting such modification. For both landlords and tenants, the following points are critical:

  1. Written Consent for Alterations: Lease agreements should explicitly state the need for written consent for any alterations or improvements. Without such consent, the tenant risks violating the terms of the contract.
  2. Avoid Implied Modifications: The doctrine of conduct cannot be used to alter the terms of a contract unless there is a clear agreement or provision allowing it. Conduct should not be relied upon to modify an agreement that is otherwise unambiguous.
  3. Burden of Proof in Claims for Damages: In cases where claims for damages or expenses are made, such as the costs of renovations, the burden of proof lies with the party making the claim. Special damages, in particular, must be strictly proven with clear and convincing evidence.
  4. Adherence to Lease Terms: Both landlords and tenants should respect the terms of their lease agreements, especially when it comes to disputes over rent and property alterations. A failure to follow the established process can result in legal consequences.

Conclusion: Upholding Contractual Integrity

This case highlights the importance of upholding the terms of written agreements, especially when dealing with issues such as property modifications. The court’s decision reinforces the notion that parties to a contract are bound by its express terms, and that conduct alone cannot alter the agreement unless explicitly permitted.

For landlords and tenants, this judgment serves as a crucial reminder to carefully review lease terms and seek legal advice when faced with disputes. The principles established here ensure that clear agreements are not undermined by implied conduct, thereby promoting fairness and certainty in contract enforcement.


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