WHY DOES THERMAL BRIDGING MATTER?
Thermal bridging is when heat moves through a material that is more conductive than the others around it. Heat will naturally travel on the "path of least resistance" across the material that is the most conductive.
This can happen in floors, balconies, and windowsills but the simplest example is in the exterior walls. In most home's insulation is only placed between studs in the wall, however those studs themselves can serve as a bridge for energy to transfer between the indoors and outdoors. To resolve this, the walls can be constructed with a continuous insulation layer, can have increased spacing between studs and can be designed with deliberate connections between materials.
The most sustainable home designs will have no thermal bridging. This is achieved when the contractor's carpentry & product installation is installed in ways that eliminate access for heat transfer through the building envelope.
HOW MUCH DOES IT COSTS?
Thermal bridging is much easier to eliminate in new home construction than it is in renovations. While there are some extra costs associated with creating a continuous insulation layer and working with a highly skilled builder, the impact on building costs is minimal.
However, since thermal bridging can be a major source of energy loss, a home with no thermal bridging will spend less on utility bills. Ultimately resulting in a net positive on the initial investment.