There are three principal layers; 1  External intercostal muscles aid in quiet and forced inhalation. They originate on ribs 1-11 and have their insertion on ribs 2-12. 2  Internal intercostal muscles aid in forced expiration (quiet expiration is a passive process).
Costs. A professional concrete contractor will typically charge $2-$4 per square foot for a simple stain application, including the sealer. A stain application with patterning and sawed lines will typically cost between $4 and $10 per square foot.
View all concrete floor videos. The cost of stained concrete can vary greatly. For a basic application of a single stain color with sealer and minimal surface prep, most decorative concrete contractors charge between $2 and $4 per square foot. As the complexity of the job rises, so will the price.