renowned expertise

in building science

Areas of expertise

Among the most important laboratory installations in Canada

Building science is the study of interactions between the various materials, products and systems used in building construction and their impact on the uses and occupants of the buildings and the environments they are located in.
A building envelope is a set of elements and/or systems that play the role of separating differing environments, as well as of protecting building occupants and materials. A building envelope also functions to control the exchanges that occur between the inside and the outside environment to which it is exposed.

It is the understanding of physical principles related to air, heat and moisture flow, and their effects, that allows the development of building envelope assemblies that can adequately contribute to the control of the inside environment while respecting performance and durability criteria.

Airtightness

An active involvement on standards writing committees, providing industry training and giving technical presentations

Moisture and energy can travel through a building envelope by air leaks or, more precisely, by the uncontrolled flow of conditioned air. Air that flows through cracks or openings in envelope assemblies can carry significant quantities of water vapor. This condition can become problematic when the moving air reaches a part of the assembly where surface temperatures are below the dew point, resulting in the formation of condensation and/or frost.
In cold climates, this can happen when warm and humid indoor air exfiltrates towards the cold outside. In warm climates, this can happen when warm and humid outdoor air infiltrates toward the air-conditioned, cool interior.

Watertightness

A central hub of knowledge and know-how

Water infiltration into, or through, building envelope systems is a common problem and the main cause of premature deterioration problems. Frequently, these issues arise from poorly designed details, lack of knowledge of material properties, or poor execution related to the use of unqualified workers, lack of quality control and/or lack of maintenance.

Thermal behaviour

Building envelope quality control

Durability

Since temperatures are seldom the same on both sides of a building envelope, heat flow inevitably and continuously occurs. This heat flow has an important impact on the building envelope’s performance. Among other things, if the heat flow is excessive, energy consumption will increase and the occupants’ comfort can be seriously compromised.

In addition, heat flow can create favorable conditions conducive to condensation if humid air comes into contact with surfaces that are below its dew point. This can contribute to the deterioration of materials and also to air quality problems arising from mould growth. It is therefore very important to take this heat flow into consideration to understand and control it to the greatest extent possible.

In order to ensure that buildings are safe and building envelopes are efficient and durable, their design and implementation process must meet specific requirements. Requirements for designers in terms of the construction and expected performance of the various building envelopes components are defined in the documents of various types such as codes, standards, procedures and other recognized references. The process of designing and constructing a building envelope must include verification that the implementation respects the requirements stated in these documents as well as in the plans and specifications. In other words, there must be quality control at all phases of an envelope design and construction project.

All buildings reach a level of ageing beyond which it is no longer profitable to maintain them in service. This is called the end of their life cycle. Every system, every material, every component eventually reaches the end of its life cycle and no longer meets its desired performance level. Design, layout and implementation of envelope components must, therefore take durability into account.

Deterioration and rehabilitation

Laboratory accredited by the main organizations recognized in North America

An important factor influencing many building performance problems is the lack of building maintenance. Maintenance is certainly not exclusive to buildings since any infrastructure must be maintained (roads, bridges, dams, etc.) However, building envelope maintenance is particular since a building envelope defines and forms a separation between differing environments that often represent conflicting conditions. It is also used to shelter and protect people.

We consider maintenance to be all planned, periodic or repetitive works aiming to keep a building in use with the objective of preserving its value and providing a reasonable level of comfort and safety for its users.

Rehabilitation is defined in terms of works aiming to achieve general improvement or compliance with current codes and standards. It is to be reinstated into the original state. Renewal is an associated undertaking that essentially aims to restore and repair buildings that no longer fill their original function due to degradations.

In-service behaviour

A reference sought by leaders of the construction community

In-service behavior differs from initial behavior due to modifications, gradual performance loss or any alteration that the building faces along its service life. In-service behavior is an essential factor that can be measured and calculated in order to check a building’s potential to react adequately.