I dealt with three home inspections this week and two of them turned up moisture in the crawlspaces.
Nearly all of our homes in the Boise real estate market are built on raised foundations with crawlspaces underneath.
Very few homes in the Boise real estate market are built on slab foundations, but slab foundations sure would help eliminate our crawlspace moisture challenges.
We have an underlying layer of clay in many parts of the Boise area, which acts as a barrier to groundwater percolating into our soils.
This, along with faulty finish grading of lots, over-watering of lawns, and downspouts dumping rain water onto the ground alongside foundations often leads to moisture in crawlspaces.
One of the homes that was inspected this week had faulty grading of the side yard that actually sloped toward the home instead of away from it.
That makes you wonder how the home ever passed the building department’s final inspection, but I have seen this situation many times.
To correct the problem, the seller of this home has hired a contractor to remove the plastic vapor barrier and dry out the crawlspace with fans over a period of several days.
Then, a landscape contractor will bring in additional topsoil and grade it so that it slopes away from the home.
Fixing these problems can be costly.
I have been involved in several transactions where remediation of crawlspace moisture cost $10,000 or more.
Some of our better builders are now installing perimeter foundation drains that pipe runoff water away from to a dry well (a pit full of drain rock that extends below the layer of clay).
In a worst-case scenario, crawlspace moisture can result in toxic mold.
Thankfully, none of my inspections this week revealed problems that severe.