Starting from the Bottom | Oregon

2 Hour Audio Course | Approval #SRA1907
This course takes a look at decisions made in selecting materials for the foundation, floor assembly and foundation types and how to avoid problems that occur from making poor choices.
0.2 ICC CEUs – Approval #27604  


Instructor: Paul Spite

When a floor collapses or when mold appears on it, we can be sure of one thing. Such problems likely began when poor choices were made selecting materials, from the level of the grade to the level of the finished floor. Like the problems they spawn, choices made in proper or improper floor design, begin at the bottom and work their way upward.

This course takes a systematic look at decisions made in choosing specific components of construction, from the ground to the top of the first finished floor. Those choices need to be sound and dependable, since the top of that floor is the base upon which the rest of the enclosure will rest.

This design process includes an analysis of water attacking the structure, why specific foundation options are selected, what framing members will support the floor, how vapor drive will be controlled, what insulation will be installed to isolate climates, the subflooring that will be the primary barrier between the inside atmosphere and any space below, and the underlayment and finish flooring that will be placed above.

If we do our job well as designers, that last component will be the only part of everything chosen, to ever need further attention or consideration from our clients.

By the end of this course, you will:

  • Understand building science principles relevant to floor system design and moisture intrusion issues that affect indoor air quality, as well as structural integrity
  • Readily identify system components in a high-performance floor assembly, such as grade, crawl space, vapor retarder, framing systems, insulation, sub-floor, underlayment and finish flooring.
  • Be able to explain how the changing codes and evolving building materials are impacting and influencing sub-flooring system design
  • Realize the principles behind the vapor drive in operation below floors, and how to anticipate and prevent the movement of moisture into flooring components.
  • Develop a solid rationale for fastener types chosen and implemented to combine flooring assembly components.
  • Have a grasp of recommended design methodology incorporating building science principles and code requirements, to ensure a designed floor assembly provides durability and increases occupant well-being

This Course Covers:

  • Exterior & Interior Parameters Affecting Performance
  • Managing Incoming Moisture
  • Foundation Considerations
  • Moisture and Vapor Control Measures
  • Framing System Choices
  • Climate Separation via Insulation
  • Fastener Selection
  • ​Choosing Subflooring
  • Underlayment
  • Finish Floor Coverings
  • Applying Design from the Ground Up
  • Problematic Design Scenario
  • Floor Assemblies in Hot Humid Climates
  • Experimental Study
  • General Design Recommendations