Crawlspace Vapor Barrier
Exposed earth in crawlspaces should be covered with a vapor barrier to control moisture by helping prevent evaporation from the soil. Polyethylene sheets a minimum of 6 mils thick, are recommended. They should overlap a minimum of 6 on the seams, and the seams sealed with tape. The vapor barrier sheeting should also be sealed around posts, piers or columns. The barrier sheeting should continue up walls a minimum of 6, and be sealed to the wall with furring strips, attachment tape or adhesive.
Pictured here is an image of the main natural gas supply line entering a crawlspace through the masonry block foundation. It appeared that there had been previous moisture intrusion with evidence of efflorescence and dirt wash beneath the pipe. It is recommended to evaluate and repair as needed to prevent further moisture problems.
From the Library of Inspection Articles “Crawlspace Hazards and Inspection” Crawlspaces can contain a large variety of hazards which are cause for concern to entrants. These hazards can include mold, fungus, pests, hantavirus pathogens, asbestos, standing water/sewage, building debris, exposed wiring and even the potential for structural collapse. It is extremely important to use the proper PPE for crawlspace inspections and to thoroughly examine the path of travel to avoid these hazards.
Modern building standards recommend that wooden floor joists have a minimum of 11⁄2 inches of bearing where they rest upon supporting structures.
Modern building standards recommend that wooden floor joists or wooden girders have a minimum of 3 inches of bearing where they rest upon supporting structures unless additional adequate support is provided.
The above is from page 9 in the course book. Can someone please explain the difference? I read these as two different length requirements for the same thing. What am I missing?
Hi, in the video Kenton said the foundation was undermined at the sump pump but he didn’t explain how it was undermined or show a picture. Can someone explain this?
In the attached inspection photo, we are looking at the main beam and its connection point to a pier. I observed evidence of past wet damage and decay. At the time of inspection, the affected areas were dry to the touch. I also observed signs of fatigue/failure of the main beam. On either side of the pier, the beam and ledger strips have dropped below the top of the pier.
In the photo, you will also note a 2 inch PVC drain pipe coupled to the original cast iron drain pipe. This drain pipe is for the washing machine. I observed improper notching of the main beam for the drain pipe to enter the dwelling. I also observed vertical penetrations through the span of the beam, on either side of the pier, for the water supply lines to enter the dwelling.
Additional notes: the floor is uneven/rolling in the kitchen/laundry area beneath and surrounding the washing machine.
It is my opinion that the observed damage is a material defect which may be affecting the structural integrity of that home. I recommend further evaluation and correction by a qualified contractor.
After reading the article titled “Crawlspace Hazards and Inspection” I now have a higher respect for utilizing the proper PPE when doing anything in a crawlspace. Prior to my pursuit of becoming a home inspector, I viewed the crawlspace as any other typical environment. I showed a disregard for the potential hazards, and had performed some work without the use of any PPE.
During my recent inspection of my own crawlspace, I was much more aware of the potentially hazardous elements I was encountering. Areas of exposed dirt, standing water on the moisture barrier, a damaged pier, and an improperly notched main beam with significant decay, just to name a few.
As an individual with a sensitivity to allergens, mold and fungus is high on my list of hazards to be aware of. In the attached inspection photo, you will see the evidence of decay and fungal-like growth on the floor panels beneath the bathroom area.
has anyone purchased a crawlspace rc car. If so how do you like it. Here in florida I have alot of crawlspaces and nasty little bugs. If it helps more than hinder i might build one.
