In the U.S., our understanding of air leakage through building envelopes has evolved over the course of 100 years or more.
Thermal bridges in walls can reduce the overall performance of a building. In addition, ignoring thermal bridges can result in significantly over-estimated building performance and moisture condensation ultimately leading to corrosion, mold, rot and more.
Today, it is well understood that controlling air leakage through building envelopes by proper use of air sealing materials and methods is crucial for many reasons.
In past articles, we have extensively covered the benefits that foam plastic continuous insulation provides for all types of construction in all climates.
R25 does not equal R20+5ci Why? Thermal bridging! The added R5ci reduces heat loss through both the wall cavity and the framing members
Tom Walker of British Plastics and Rubber says that “One trend in the [British] construction market is the use of pre-fabricated Structural Insulated Panels (SIPS).
If a property owner is considering an upgrade to improve energy efficiency, a building envelope inspection is recommended first.
The only way you can have any effect on the building code is to get directly involved. In fact, with a little effort you can change current code language that is unclear or write new sections of code based on your area of expertise. The code development process is open to anyone having influence if initiative is taken.
The task of assembling the components of framing, cladding, insulation, structural sheathing, and various control layers into a durable, cohesive system is a similar balancing act, but there are solutions.
Nowadays it’s common to see other kinds of WRBs on commercial products such as peel-and-stick, fully self-adhered membranes, spray applied membranes, and so forth.
Integrating continuous insulation with traditional building methods is much easier than it sounds. Take tar paper for example. Tar paper is historically the most common water resistive barrier (WRB) for residential construction.
A labor cost effective option with certain products is to use continuous insulation as its own WRB, by taping all seams and overlapping the insulation boards over the flashing.
Today CI is virtually required in commercial construction. But residential walls, typically framed with wood, not steel, have less of an issue with thermal bridging. So is the use of CI on these types of structures worth it? Absolutely!
Most cavity insulation products are very effective at minimizing sound transmission. Therefore, use continuous insulation to keep warm and insulate the cavities to reduce noise!
Humans aren’t good “talking” thermometers, because we “feel” thermal conductivity. Want proof? As my college physics prof often told us, you’d rather the outhouse had a wood seat than a porcelain one on a cold night (even though they’re the same temperature)!