Reuben has been meaning to blog about the subject of this episode since 2014. He was finally able to create and post it when it was brought up by an internal team question.

Today, the gang will be talking about the issues of rotted rim joists, beam fill, and floor structure problems that tend to come up in old houses. The gang answers the questions “why it happens,” “when it happens,” “what are the signs that one should look for," and “ when does it need further evaluation.”

The show starts off with Reuben sharing what prompted him to write this post. He shares an inspection he participated in with Duane Erickson, now a retired home inspector, from whom he got the term “beam fill.” He also shares an inspection from the past in a house that had rotted rim  joists behind beam fill, and how much it cost to be fixed.

Then, Tessa explains how fiberglass insulation at a rim joist adds only a little bit of an R-value and how it is actually a bad thing when it comes to building science regarding heat, airflow, and moisture movement. She shares how a homeowner can still have airflow getting through the insulation when fiberglass is used at a rim joist and how it isolates it from the heat and the airflow in the basement.

Bill then asks the following questions:

• How much money does it actually save me in the long run in terms of heating cost or cooling cost to spray a rim joist?
  
• What are the risks of creating some sort of rot or mold?
  
• How often do you think this is a concern in older houses?
  
• In making some improvements to one’s house, can durability and comfort be achieved, or is it a sliding scale, where you give up one to accomplish the other?
  
• Do stucco houses have this problem more frequently than wood-sided houses?
  
• Will water vapor cause rot?
  

Related link: https://www.structuretech.com/blog/beam-fill