Net-Zero Energy Building and Building Envelope

Net-Zero Energy Building and Building Envelope

The detrimental effects of carbon fuel consumption on the environment have stimulated development of a ‘net-zero’ energy measurement for public and private buildings. A ‘Net-Zero’ building is defined as one that creates as much energy as it consumes on an annually averaged basis. Currently, energy production is not incorporated into the construction of most commercial properties. The primary focus is on creating a building structure that consumes energy efficiently. Once energy efficiency is mastered, the addition of energy production systems will move the project closer to the net-zero goal.

The first consideration for energy efficiency is the building envelope and how that structure controls indoor air quality and moisture levels. Both liquid and gaseous moisture (water and humidity) can cause mold growth and degrade building materials. Preventing entry of either will maintain the air quality and durability of the building over time.

Preventive and remedial measures regarding moisture intrusion include: rainwater-tight detail design, prevention of uncontrolled air movement, reduction of indoor air moisture content, reduction of water vapor diffusion into walls and roofs, selection of building materials with appropriate water vapor transmission characteristics, and proper field workmanship quality control.

Many builders use a rainscreen design to keep weather water at bay. A rainscreen, such as, DELTA®-DRY, has a structured membrane that provides drainage and ventilation, as well as a complete capillary break behind the cladding. It protects the building envelope from bulk water intrusion (i.e. wind driven rain), and manages water leakage through the cladding. DELTA®-DRY also captures and drains transient moisture migrating through the wall structure. A rainscreen provides an air-gap on the interior and exterior side of the membrane for drainage and ventilation.

Because moisture can also intrude through humidity, barriers must be installed to control its movement into and out of the building. A failure of the vapor  barrier can result in condensation inside walls and crevices. The resulting moisture can cause the development of mold. The simplest approach to creating an airtight enclosure is with a premium air and moisture membrane such as DELTA®-VENTA SA.

As the commercial property design and building industries advance towards the goal ‘net-zero’ energy, properly detailed building envelopes will continue to be more important. To learn more about building envelope membranes that can help you as you move towards net zero energy, contact us.