What is a building envelope, why is it beneficial and how does it save money?

A building envelope is like a shell, barrier or seal of protection against the outside world. Anything that separates the internal building from the external environments makes for this envelope. This includes roofs, doors, walls, and floors. In the winter, it prevents heat transfer and helps the building remain cool during the summer months.

The barrier is pivotal to building’s structural energy because a good envelope ensures an edge to better in-built HVAC systems & lighting, implying lesser money spent on equipment. The envelope accounts for at least 30% of the energy consumed. The older buildings were never constructed keeping an envelope in mind, which is why they are so energy inefficient and spend a lot on retro-commissioning it.

Tight Vs. Loose Envelopes

Tight and loose are the two types of building envelopes. A tight envelope allows for very few air leaks because of the insulants, sealants, & energy efficient windows used. The tight seal facilitates a well controlled indoors environment implying more comfort, reduced moisture, natural ventilation (without the need for mechanical needs).

Loose envelopes can be achieved by design as well as poor construction of the building. They result in unwanted moisture, poor indoor air quality, increased contaminations, bad health of occupants, lesser efficiency and major loss of air conditioning and heat implying higher energy usage & costs.

Functions of a building envelope

Structural support

The envelope essentially ensures that the building’s structure is stable and sound, and that it provides the necessary support vis-à-vis weight, & load bearing. Moreover, it also helps meet local regulations and building codes.

Climate Control

As previously discussed, the envelope takes care of air regulation, and sustainably, whilst also being optimally energy efficient. The local climate usually determines construction. For example, a cold climate will mandate stronger infiltration.

Aesthetic Appeal of a ‘finish’

A visually pleasing exterior is important to all types of buildings. Because the envelope is literally the building’s exterior, it should be designed realizing that explicit requirement of locales.

Components of a building envelope

1. Foundation

A combination of slabs, footings, and concrete walls makes for the foundation of a building. Its purpose is to transmit the building’s loads to the underneath grounds. The envelope needs to offer moisture control to support the transmission and also prevent the thermal energy from seeping inside the building.

2. Walls

Walls ensure exterior support, control and finish of a building. The wall system elements are insulation, exterior cladding & sheathing, vapor barrier, water resist and condensation along with thermal energy regulation and control.

3. Air

Air-tightness is indispensable to a building’s overall efficiency. It defines whether or not a building’s envelope is loose or tight. Solutions like sealants, sheathing, spray foams, membranes, etc., account for up to 20% of energy savings.

4. Movement

Temperature changes, unpredictable weather, and ground movement make the building move, literally. It’s important that the building envelope accommodates these movements because a rigid envelope results in cracks and other small stresses.

5. Energy

Modern construction takes into account energy consumption on priority- including new constructions as well as retrofits. Energy efficient constructions are cost-effective and eco-friendly. The building needs to be designed in a manner that prevents energy loss of any kind.

6. Durability

A proper envelope ensures a comfortable longevity of the building and contributes to greater structural integrity. Functionality, optimization and efficiency need to be taken care of collectively.

 

Conclusion

Building envelope is pivotal to a building’s structural soundness, energy efficiency, climate control and proper functioning. A sound building also uses less energy which is great for the environment as well as your pockets.

The Cotocon Group has an able team of experts with vast experience. We are qualified to take care of all the energy services, from facilitating legal compliance to making your building the most competitive & efficient through audits and retro-fits. Contact us to know more!