The building code defines residential construction as one, two or three family dwellings. Broadly speaking everything else is commercial. While the two codes have different requirements for insulation, the principles are exactly the same: a building must be properly air sealed and insulated to be economical to operate and comfortable to occupy. High insulation values mean little if outside air bypasses the insulation. This is true no matter what construction method is used.
Ohio uses the 2009 International Energy Conservation Code to govern requirements for the performance of commercial buildings. The 2009 IECC requires the use of continuous insulation on wall assemblies, which was a significant step forward, especially for metal frame buildings.
Unfortunately, the code does little to address air sealing. At Pure Seal we have seen the consequences of this omission and as a result, we pay great attention to proper air sealing on all our projects. Thankfully polyurethane spray foam allows us to insulate and air seal with one material.
Commercial buildings are many things. From factories to nursing homes, they come in all shapes and sizes and are constructed in many different ways. Broadly speaking, we can look at metal, wood and masonry construction. Sound insulation is another area where foam can make a real difference.
Metal construction
Metal is common in commercial buildings. Whether light gauge frame or structural steel, the metal presents an insulation challenge because of its high conductivity. Without a continuous layer of exterior insulation, metal will conduct massive amounts of cold to the inside of the building, which reduces the true r-value of the wall to a fraction of the nominal value of any cavity insulation. As if that wasn’t enough, the ice cold metal can cause condensation and freezing of air borne moisture, either inside the wall cavity or on the drywall. Condensation is also a very good reason why air permeable insulation such as fiberglass should not be used in buildings with an exterior metal skin. While common because of low cost, vinyl covered blanket insulation will let humid air reach the metal where it will condense and freeze in low temperatures. Closed cell polyurethane spray foam provides insulation and vapor control and is the product of choice for metal application.
Wood construction
Commercial wood frame buildings mostly distinguish themselves from residential construction by their size. From an air sealing and insulation perspective there is little difference but the cost of a potential system failure is much greater; a ruptured pipe caused by a drafty floor cavity is much worse when it happens on the third floor of a nursing home.
Masonry construction
Brick, block and concrete walls are strong and long lasting but they must be insulated to provide any kind of comfort. In new construction, this is best achieved with spray foam, either on the outside of the structural wall or on the inside behind the drywall. In either case the foam should be continuous so it is important to leave a gap between any framing and the masonry to allow for insulation. In a retrofit situation, it may be possible to fill cavities inside a wall with foam.
Sound insulation
High-level sound insulation requires more than just wall cavity insulation. That said, we have achieved significant improvements in office environments by injecting Air Krete foam into the walls. Air Krete flows to fill all gaps and openings through which sound waves can travel; because of its mass, it also deadens the wall.
