Hotel builders use building energy modelling

There is a new energy code in Ontario that is changing the way hotels, especially limited service hotels, are b

By Stephen Blood

There is a new energy code in Ontario that is changing the way hotels, especially limited service hotels, are being built.

The Supplementary Standard SB-10 of the Ontario Building Code,
combines the requirements of the latest ASHRAE 90.1 Energy Standard with
additional provisions from ASHRAE 189.1 2009, a Standard for the Design
of High Performance Green Buildings.

This new code effectively jumps from 1999 to 2013 standards in one
giant step, giving Ontario the most progressive energy standard
requirements in North America. Hotel builders in other areas are
watching to see if their provinces will follow suit.

Strict, often costly new requirements for new builds

For new build hotels, this means finding ways to save money while meeting the strict and often costly new requirements.

Urban and full service hotel designs, especially those that have
large window areas, have begun utilizing building energy modelling as
part of their design plan. This service, usually reserved for LEED
(Leadership in Energy and Environmental Design) certified projects,
helps to optimize the building envelope and mechanical and electrical
systems for LEED credits.

Architects are now using this building energy modelling to
efficiently meet the new energy code standard. This process allows hotel
builders to evaluate various energy saving measures for return on
investment in order to choose the most cost effective solution to the
new regulations.

The cost of a building energy model often pays for itself by
providing energy efficient options, complete with expected payback
periods.

Dealing with PTAC units

Limited service hotels face a slightly different dilemma. While they
usually have smaller window areas, they are traditionally heated and
cooled with PTAC units, which can be easily serviced and replaced.

Typically, these units use electricity as a power source, which
places them squarely in the new codes most severe Ontario Climatic Zone
7. This means that hotels with electric PTAC units need to be designed
as if they were located in Thunder Bay even if they are located in balmy
St. Catharines!

New requirements for more energy efficient lighting and heat recovery in hotel exhaust systems have also been called for.

Many of the options for optimizing mechanical and electrical systems
to minimize the economic consequences of the new requirements are not
available when using PTACs.

In this case, energy modelling can be used to find economic justification for a more expensive mechanical system.

There are a few PTAC units that use hot water for heating, which may
become a viable option if they become less complex and expensive.

South-facing window requirements limit site planning

Stringent requirement that more windows face south, rather than east
or west, can be very restrictive on site planning for a hotel. An
otherwise desirable site that is long and narrow in the north-south
direction or has lake views to the east or west may not be a viable
option under the new code.

Determining the most cost-effective solutions

Balancing the long-term payback of energy improvements, against often
critical capital costs, will define building decisions. Building Energy
Modelling can help determine the most cost effective solutions.

Modelling should be done at the earliest stages of the project to
provide the largest number of options and get maximum return on
investment.

Energy savings from innovative building envelopes, alternate energy
sources, heat recovery, sun shading, and building controls solutions can
also reduce initial capital costs by downsizing expensive mechanical
systems.

For example: the use of solar energy to preheat fresh air and provide
hot water has produced significant savings for some projects. This
strategy dovetails smoothly with the philosophy of Integrated Project
Delivery (IPD), in which design and construction methods and cost
choices are integrated from the first moment a project is considered –
now with a new emphasis on energy and sustainability.

Minimizing construction costs while complying with regulations

While following prescriptive measures may minimize design costs, it
will not guarantee effective control of construction costs, which can be
10 to 20 times the related design fees.
Hotel owners and developers
need to evaluate how construction costs can be minimized while
complying with the new regulations by including building energy
modelling in the design process.

About the author

Stephen Blood is an associate at Chamberlain Architect Services,
Limited in Burlington, Ontario. A winner of both the W. Gerald Raymore
and Henry Adams Medals, Stephen has been solving building challenges
with the Chamberlain Group since 1996. He is a member of the Ontario
Association of Architects (OAA) and the Ontario Building Envelope
Council. Stephen’s degrees include a Masters of Architecture, Bachelor
of Environmental Design Studies, a Diploma in Computer Programming and a
Bachelor of Arts. Stephen may be reached at sblood@chamberlainIPD.com.