There was a time when cavity wall insulation was considered an efficient method of energy loss prevention. That time has passed.

History Of Cavity Wall Insulation

In years past, cavity wall insulation was considered efficient and less expensive than most other forms of wall insulation. It was used to reduce heat loss through a cavity wall by filling the air space with a material that would inhibit heat transfer. This was done by immobilizing the air within a cavity, preventing convection, and thus reducing heating costs. Many products, such as spray foam and fiberglass batting, were used to fill in the space between wall studs. It maintained existing wall thickness, reduced condensation, and caused minimal disruption to daily life when installed.

However, over the years many disadvantages to cavity wall insulation were determined. The most prominent was thermal bridging. A thermal bridge occurs when there is a gap between materials and structural surfaces. It also occurs each time there is a door or window. Thermal bridges have a detrimental effect on the energy efficiency of a house. Cavity insulation limits thermal protection to just the area in the wall cavity and allows a thermal bridge heat transfer through framing studs. The studs can also pull heat from the insulation.

Crossing The Thermal Bridge

Today there is a much more cost-effective way of keeping a house heated and cooled. The method is called continuous insulation and is usually referred to as CI. Continuous insulation effectively stops thermal bridging between the outside temperature and the inside wall cavity, i.e. inside temperature. This reduces heat loss and increases the effective R-value of a wall system. By keeping the cavity insulation warmer and protected from the stud’s thermal bridging allows the cavity insulation to insulate to its full potential. Also continuous insulation can move the dew point from inside a cavity to the exterior wall, which helps protect against the formation of mold and mildew by keeping condensation out of the wall cavity. With the inclusion of a drainage plane and moisture barrier, CI can provide protection against water intrusion, degradation of materials, and extends the lifespan of a home.

Which CI?

Although there are many products that can be classified as CI, one now stands out as providing very effective continuous insulation benefits. Wall CI Board products manufactured by Atlas Roofing Corporation, have a polyiso foam core that provides a higher level of thermal performance compared with Extruded Polystyrene (XPS), Expanded Polystyrene (EPS), and mineral wool. Atlas Wall CI Board products are backed by a 15-year thermal performance warranty. Its air and moisture barrier properties are field proven, lab tested, and code compliant. These CI products meet fire ratings and codes with low flame/smoke propagation. Polyiso chars in place and doesn’t drip like other plastics. Wall CI Board products are stable, durable, non-corrosive, and compatible with most sealants and adhesives. Lightweight Atlas Wall CI Board products are much easier to install, requiring only standard tools and fasteners.

Why Today?

Building science has proven conclusively that CI is the most effective way to insulate building envelopes for energy savings. More than 90% of the U.S. jurisdictions now prescriptively list the use of continuous insulation for steel-framed walls above grade.

Closed-cell polyisowall insulation is an effective choice for CI, and Atlas Wall CI Board is a leader in polyiso products. The company has eight state-of-the-art manufacturing plants dedicated to the Atlas Wall CI Board product line.

Complete details on continuous insulation and the benefits of Atlas Wall CI Board products can be found at www.AtlasRoofing.com/Continuous-Wall-Insulation.