The Pivot is a new residential rental development located in North Vancouver. The developer, Adera Development Corp., is using Cross Laminated Timber (CLT) to construct this project. CLT is made of engineered wood panels, typically three to nine boards thick, and laminated with special glues at high pressure with each layer laid in a different direction to create a strong building material. SmartWoodTM is being used as floor panels, in place of conventional framing of joists and sheathing. The project consists of a six-storey wood framed building, containing approximately 88 rental units, built over a two and a half level concrete parking garage. The building is designed to meet the energy target of Step 3, as outlined in section 10.2.3 of the 2012 BC Building Code.  Step 3 energy targets include TEUI (Total Energy Use Intensity) <=120, and TEDI (Thermal Energy Demand Intensity) <=30 (kWh/m2*year). A detailed energy model of the building has been prepared, to confirm the anticipated energy performance targets can be achieved; modeling results confirm the project target values to be TEUI=101.9 & TEDI=29.6 kWh/m2*year.

Williams Engineering (WE) supplied mechanical design services for this project which included heating, ventilation, plumbing and fire protection; as well as energy modelling services. The building heating system is mandated to be “district energy ready” with the use of hydronics throughout the spaces. The heating in each unit is a radiant floor system, and the domestic hot water is provided by a boiler/storage tank generation system with domestic hot water recirculation to ensure hot water is provided to all necessary plumbing fixtures. Currently, the hydronic plant consists of separate boiler plants for the building heating and domestic hot water systems. Cap-offs have been included in each system for direct connection of the DES Energy Transfer Station when they become available.  The ventilation is provided by an in-suite HRV unit, which removes stale air from the bathrooms and provides outdoor air in each bedroom and living area, while saving energy by transferring energy from the stale airflow into the incoming outdoor airstream. Corridor pressurization is provided on each floor by a roof top air handling unit complete with a heating coil to temper the air. Plumbing is designed for all residential fixtures, roof and site drainage requirements. A performance specification sprinkler system is designed to meet NFPA-13 requirements.

The location of this project (located close to the confluence of two active waterways) has resulted in the need to “think outside the box” while designing the mechanical systems for this project. The level of the water table, and the presence of the waterways, result in a requirement to address subterranean hydraulic pressure, as well as anticipating intermittent over-land flood conditions.  A series of wells have been designed, to provide pressure relief ports, in the case of rising groundwater; other measures are in place to limit the opportunity for over-land flow to enter the parking structure.

Saving time through the prefabrication process of CLT, also streamlines the efficiency of the installation process, thus creating a not only sustainable but environmentally responsible project. Williams Engineering continues to stay committed to engineering cities that are safe, inclusive and resilient.