Sustainability is increasingly a core consideration in the multi-family residential sector as developers adopt low-carbon solutions such as geothermal to meet stringent green standards, rising carbon taxes, and shifting market preferences.

Diverso Energy - a geothermal pioneer in the GTA - has collected key insights from a recent panel of experts to assist developers considering a geothermal heating and cooling system for their next project.

The panel led by Tim Weber, Diverso co-founder and CEO also featured Jeff Wilkinson, President of CB Wilkinson and Jennifer Burstein, President of NOVI BLDS. Together, they recommend adhering to several best practices to keep projects on track and within budget.

• Early engagement: Bring all key stakeholders into the project early to align goals and tackle potential issues proactively.
• Site preparation: Complete site remediation and preparation before geothermal drilling to avoid delays and complications.
• Effective scheduling: Coordinate geothermal activities with other trades to prevent scheduling conflicts.
• Continuous improvement: Learn from past projects to refine processes and boost efficiency.

Early engagement

Integrating geothermal systems into your construction schedule begins with a well-crafted game plan, says Weber, whose company leverages decades of experience gained delivering more than 300 projects. That means including geothermal in the design phase.

Involve key stakeholders - such as the geothermal partner, mechanical engineers, and construction managers - from the start. Creating a collaborative environment from the outset minimizes miscommunication and clarifies roles, leading to a smoother integration of geothermal with other trades, often resolving challenges before they escalate.

Understanding the geothermal sequence

Geothermal drilling is largely "out of sight, out of mind," but it does impact construction timelines. The financial impact of geothermal installations is closely tied to effective scheduling. Delays, especially later in the project, are costly. Coordinating scheduling matters with a client’s project management team can ensure a seamless experience.

Minimizing disruptions, Diverso drills the borefield before excavation begins, returning for horizontal tie-ins only after shoring and excavation are complete. The tie-in process involves connecting the ground loops to the building’s mechanical system through horizontal connections. As for the system itself, each borehole is neatly located underneath the building footprint.

Managing site preparation and remediation

Challenges such as contaminated soils can jeopardize the drilling process. Addressing these issues before drilling begins through close collaboration between your geothermal partners, consultants, and engineers is key to mitigation projects.

Diverso’s team recently tackled soil contamination at Foret Condos by Canderel, a former service station site, by employing a double-casing process and adhering to strict safety protocols. This ensured that the borefield was installed quickly and safely.

Navigating foundations and site-specific challenges

Specific foundation types also present unique challenges for geothermal integration. For instance, spread footings can create space constraints that complicate the tie-in process. Raft slabs - particularly those designed as bathtub slabs - also require careful planning to avoid negatively impacting the waterproofing layer. Raglan House Condos by Camrost Felcorp is one of many Diverso projects utilizing bathtub raft slabs. Their in-house engineering team also employed quad pipe as an alternative borehole design, highlighting their expertise.

Managing the raft slab’s waterproofing during the tie-in is critical. Any penetration of the waterproofing layer must be carefully planned for and coordinated with the geothermal partner, especially in low-risk areas like the mechanical room, where potential leaks can be more easily managed.

While complex, bathtub raft slabs can simplify the geothermal tie-in process by providing full site access and reducing the time needed per borehole. However, despite these efficiency gains, Weber stresses that “Diverso still requires full site access for at least two weeks. With proper coordination, we can then share the site to begin raft slab construction.” Drawing on past projects, he adds, “Based on our experience, the overall schedule impact of a bathtub raft slab is about the same as conventional spread footings.” Regardless of the foundation type, meticulous sequencing and planning are crucial for mitigating schedule impacts and conflict on site.

Choosing the right geothermal partner

Best practices improve geothermal projects, but start with selecting the right partner. As Ontario’s first vertically integrated geothermal company, Diverso Energy consolidates engineering, drilling and construction management in-house. Vertical integration offers significant advantages, particularly in the design, installation, and monitoring of geothermal systems. By managing these processes in-house, Diverso optimizes coordination and quality control. Its unique geothermal utility model is backed by CVC DIF, a global infrastructure fund manager with over €18 billion in infrastructure assets under management.

Similar to that of a traditional natural gas utility, Diverso’s Energy-as-a-Service (EaaS) model shifts costs from capital expenditure (capex) to operational expenditure (opex). This innovation allows developers to incorporate geothermal infrastructure into their buildings without the upfront payment, providing tenants with a fixed-cost, low-carbon solution over a 30-year term that balances sustainability with affordability.

For a deep dive into the topics covered, please view the official webinar recording below.