The Forgotten Crawl Space (Part 2 of 2)

(Continued from: Part 1)

A bit more about the crawl space . . .

We got a call a few years ago about a property that had a “moisture vapor” problem in the crawl space.  That’s what an inspection report listed it as.  So, I went to look; sure enough plenty of water (probably two to four inches at the time) under the home, and in the winter again.  The inspection report (crawl space section) recommended installation of a “moisture vapor” barrier to stop the moisture and vapor from getting into the home; nothing else was recommended.  But, where does the water go when you seal the ground below it?  Hmm.

Possible solutions . . .

I suggested we first get the water out (with a sump pump set-up), figure some ways to keep it out (better exterior drainage), and then put the barrier over the ground in the crawl space.  The soil was clay (we call it ‘adobe’ here) and it’s great for many things, but it doesn’t allow the water to seep into it very quickly, and it’s rather expansive (it grows with moisture).

If we had just put the barrier down, without thinking about the water that already gets into the space we would be compounding the problem because then the water couldn’t even get back into the soil when the rainy season ends each year.  The barrier would stop the “rising damp” (moisture that rises up out of the ground into the crawl space, becoming vapor) but it would not have dealt with the entry of rainwater into the space.  To me, it’s like building a beautiful remodel but ignoring the cracked and settling foundation below the whole thing.  (See examples in Part 1)  It’s just not right!  We have so many stories like these that we could share.  But there are a lot of other parts of the home that are also important to cover.


(These photos are from our collection.  Our own crawl space shortly after moving in – we were just starting to clean up this mess.  How many problems can you find?)

To continue . . .

Ultimately, this owner went with my suggestions and got the best of all solutions: getting the rainwater to stay out of the building and keeping the vapor (relative humidity) in the space to an acceptable level.  Solved!  And, years later no issues in or around the home from the previous moisture.

Other complications many folks don’t know about . . .

By the way, vapor is a potential problem under homes in summer also, if you have un-insulated cold water piping or air conditioning lines and ducts down in your crawl space.  The moisture rises up into the space, evaporates (becomes vapor) into the air, then condenses onto the cold surfaces of the piping, ducts, tubing and other things.  Think of foggy windows on a cold morning in a snowed-in lodge.

Another issue with moisture and such below the home can be respiratory problems for the occupants.  Many of us are resistant to most of these because of strong immune systems and such, but it’s still a big consideration.  You should have the indoor air quality in your home checked by an indoor environmental professional, particularly if you are prone to breathing or other health problems that can be associated with what happens inside of your home.

What to look for in your crawl space . . .

If you do go into your crawl space pay attention for signs of life: nesting debris, bio-colonies, discolored wood, fuzz on surfaces, rotted wood, soft/wet soil, nasty smells; as well as leaks from water lines, high water stains on the foundation, etcetera.  You’ll want a good quality respirator, particularly if you suspect something is going on down there.  (Eg. Critter nesting debris can be infected with “Hanta virus” – very dangerous to us . . . probably other harmful things also.)

There are additional things to pay attention to (definitely an exhaustive list but a good start) . . .

Cracked, chipped, leaning or heaved foundation; exposed reinforcing steel; rust or colored powder on the concrete surfaces; stacked blocks or shims; rusted, broken or loose hardware (bolts, straps, other similar); moisture penetrating through the foundation; puddles; drainage lines; holes through the foundation (that are not sealed properly); loose posts, beams or other structural items; sagging insulation, ducts, wiring, piping; sump and/or pump locations (should be located in low spot/s and/or have drain lines to gather and move water to them; should also be reasonably easy to access and maintain, if possible); check that drain pumps are hooked up to protected electrical circuits (get your electrician to check it if you’re not sure) and have proper discharge piping (as these are not passive items they should be checked regularly).  If you think anything looks like it should have more support call a building contractor or an engineer to look at it.

If you see damaged spots (or any unusual looking discolorations) on any of the framing or sheathing, or any leaking from pipes, or any ducts have separations in them,  it’s time to call a professional for an assessment of what’s happening.  Don’t think, “It will go away,” or “It’s under the house; I just won’t worry about it.”  It may very well get you someday.  Or, someone you care for.

Knowledge is good . . .

If you know what’s going on in your crawl space, you’re armed and ready to take the next steps, and the more you know (and the sooner) . . . the better for you.  These things usually cost much less when they’re caught early.  Be sure that if you try to sell the home, you’ll likely have to deal with it at that time.

Basically, just think of the space as a cave that needs to be explored!  Or you could get a friend, suit him (or her) up with the proper protection, get the digital camera ready and send him/ her into your crawl space.  The photos are good to keep for reference also.  Put them onto the computer and zoom in to really look closely at what is down there.

Drone tanks

Won’t it be nice when crawling drones become more affordable and of high enough quality to help with checking out a crawl space.  (Flying drone would get caught by the obstacles.)

Action is critical . . .

When you find anything that could require attention, call a professional or attend to it yourself.  It’s so much better to get this done than to put it off.  You may be able to spend a few hundreds of dollars rather than tens of thousands a bit later.


(Read Part 1)

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