Everyone knows better than to leave his or her coat open while walking outside in wintertime. The heaviness of the material will not matter when you have a crack at the zip. Similarly, building insulation that is not continuous will be less efficient, despite its high R-value. The escaped heat will be a waste of both money and energy. 

The International Energy Conservation Code places a requirement of continuous insulation in its building’s structures. The 2012 revision explains that all eight climate zones in the US require extreme insulation in-grade walls, roofs, and floors.

IECC adds that continuous insulation helps reduce moisture loss and lowers condensation within the envelope assembly. It requires the use of continuous insulation that runs across all thermal bridges to eliminate the use of fasteners and service openings. The use of CI reduces the use of fiberglass installed inside wall studs, which has been a standard part of light constructions throughout the decade. 

Types of continuous insulation products

Expanded Polystyrene – EPS

EPS is the most commonly used rigid foam because of its exceedingly low prices averaging 31 cents per square foot. It has a moderate R-value hence is not the most suitable for constructions that need higher quality.

EPS has low compressive strength and tends to absorb more water than other forms. The structural compounds of EPS are Structured Insulated Panels and Insulated Concrete Foams. EPS must be a cover for house wrap and get extra support from plywood and OSB when used in sheathing constructions.

Extruded Polystyrene

Many environmentally conservative builders do not find this foam material convenient for their projects. Its makeup includes the flame retardant ingredient HBCD and blowing agents that contribute to global warming. The perk is that it works excellent in hot regions and highly flammable spaces.

This foam has a moderate R-value and prices at approximately 47 cents for each square foot. It is stronger than EPS and offers better resistance against water intrusion. It is convenient for the construction of under slabs and applications that fall under the grade. 

XPS is available in both unfaced and faced formats. Star R Foam produces accurately engineered XPS and has earned its name among the giants of foam manufacturers in the nations.


This foam is the most expensive variation of all rigid foams. It costs averagely 70 cents for each square foot and has a thickness of one each for each panel. The higher R-value makes it worthwhile for constructions that need increased durability. 

This foam absorbs water but is applicable as WRB under the cladding. The longevity of the foam is a scientific complication that depends on the climate of the region. 

Natural continuous insulation products

Mineral wool

It has a lower R-value than most synthetic products. Mineral wool has high permeability and is easy to use.


This natural material has excellent acoustic control and extended durability. It is, however, limited and, therefore,,, suitable as a niche product. It has a low R-value of 3.6 but is convenient for use in areas that need a high flame resistance quality.


Continuous Insulation Products
Star R Foam
3220 Avenue F
Arlington TX 76011 US

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