BUILDING ENERGY ENGINEERING – DESIGNING THE FUTURE OF BUILDING CONSTRUCTION
Embracing the Inevitable
Designers, contractors, developers and building owners/homeowners alike find themselves challenged to comply with increasingly rigorous building energy efficiency targets, as mandated by local, regional and national building codes.
In late 2014, the British Columbia Building Code (BCBC) introduced new requirements for energy efficiency in housing and small commercial and industrial buildings. The 2018 version of the BCBC includes additional technical provisions, such as higher insulation rating requirements and tighter building envelopes coupled with controlled supply and exhaust air capabilities.
Changes in government regulations encompassing such industry-wide shifts in focus present great opportunities for engineering and construction companies prepared to embrace the new business landscape.
In other words, don’t fight City Hall; join the party!
With foresight and no small degree of courage, this is precisely what one of my clients decided to do. For over two decades, ROV Consulting Inc. (www.rovconsulting.ca) has enjoyed a strong reputation for delivering structural engineering design and consultation services to the building construction industry. However, broader industry trends towards sustainable building design and practices prompted ROV to invest heavily in developing in-house expertise to model, test and certify energy efficiency performance ratings for homes and commercial buildings.
So, what does all that look like?
Building Energy Engineering Designs Homes of the Future
Using sophisticated computer energy modeling techniques, ROV can precisely replicate the thermal envelope of any building and calculate expected energy performance. Inputs factored into the analysis include:
The orientation of the building accounting for seasonal variations and building lot features
Number, size, location and physical properties of windows and doors to be installed
Quality and quantity of insulation placed below the slab, in and on the walls and in the roof spaces
Types of building materials and assemblies used.
Energy modeling allows ROV to assess and fine-tune building designs to meet minimum energy performance requirements mandated by code or offer superior energy-saving design properties inherent with Passive Building, R2000, Energy Star(TM) and Net Zero Energy Building designs. ROV can customize the building envelope plan to satisfy virtually any desired energy performance objective.
Using energy modeling, ROV can calculate the expected return on investment when selecting superior energy-efficient designs. Customers can compare the payback time required to offset higher construction costs with savings from significantly reduced utility bills, smaller mechanical systems and footprint requirements and extended building life.
ROV can test the completed building to measure energy transfer and air leakage parameters and overall energy performance against the design model. As a final step, ROV’s in-house Energy Advisor can certify the building achieves a validated energy efficiency rating.
Adding Up the Wins
Employing building energy engineering services offers significant benefits for designers, developers, builders and owners alike:
Following a performance-based building energy compliance path through modeling instead of the prescriptive approach can substantially reduce materials and labour costs (for an explanation of the differences between the two methods, refer to the end of this article).
Developers, builders, renovators and designers can customize their framing, building envelope, window-to-wall ratios and methods for renovation and upgrading.
Accurate quantitative analysis of building envelope design before construction leads to fewer costly design changes during construction.
For contractors, lower construction costs provide a compelling competitive edge.
A simplified review process for inspection agencies equates to faster turnaround times on building permits and approvals.
Contractors can elevate their perceived value and demonstrate they are staying current with trends in sustainable building practices.
In more energy-efficient buildings, residents will experience a cleaner, healthier and more comfortable living environment while achieving lower greenhouse gas emissions.
Customers enjoy more control over what they receive from their building investment.
WHAT DO YOU MEAN BY PRESCRIPTIVE AND PERFORMANCE PATHS?
Both the BC Building Code and the National Building Code of Canada offer two paths for building energy compliance – Prescriptive or Performance:
The Prescriptive Path requires that each component of a structure is built to a prescribed standard. For example, a standard 2x6 exterior wall structure must meet a minimum prescribed R-value of 17.48. While working with the prescriptive path is more straightforward and does not require the use of computer programs during design, it offers no opportunities to optimize the use of building materials and labour and reduce costs.
The Performance Path requires that the building as a whole performs to a prescribed standard. In other words, a building shall not exceed the energy target of the identical unit constructed using the prescriptive path. The performance path requires sophisticated design software used by building energy engineering experts to determine the most efficient use and placement of materials to meet energy objectives – typically saving thousands of dollars in the final construction cost.