Crawl Space code height

We are looking to buy a house and had a home inspector come and comment the soil in the crawl space was wet. He also mentioned the space below the basement subfloor was only about 2 inches high. We are in Colorado and our city follows the following building codes

2015 International Residential Code (IRC)
2015 International Building Code (IBC)
2014 National Electric Code (NEC)
2015 International Plumbing Code (IPC)
2015 International Mechanical Code (IMC)
2015 International Fuel Gas Code (IFGC)
2015 International Energy Conservation Code (IECC)
2015 International Swimming Pool and Spa Code (ISPSC)
​2015 International Existing Building Code (IEBC)
2009 ANSI (As referenced in the 2009 International Building Code)

The house was built in 1985 and I can’t find anything in the current codes that say if a crawl space has to be a certain height so I can begin to look if was also the same when the house was built.

We also had a structural engineer out and mention the area below the house needs to be dried out which we know.

So before we bug the county and city, is there a code for the height of crawl space?


Crawlspace - clearances.jpg

I would think that would be a local code to your area.

In my area, anything built in 1985 would be a slab foundation. But obviously, this does not hold true for the entire country.

Nice diagrams

Here this is noted on the Termite Report as well.

copied from 24MB file pg 212
Sec. 2516.
(a) General. The requirements in this section apply to all wood frame construction.
(b) Preparation of Building Site. All stumps and roots shall be removed from the soil to a depth of at least 12 inches below the surface of the ground in the area to be occupied by the building.
All wood forms which have been used in placing concrete, if within the ground or between foundation sills and the ground, shall be removed before a building is occupied or used for any purpose. Before completion, loose or casual wood shall be removed from direct contact with the ground under the building.
© Protection Against Decay and Thrmites.

  1. Wood support embedded in ground. Wood embedded in the ground or in direct contact with the earth and used for the support of permanent structures shall be treated wood unless continuously below the groundwater line or continuously submerged in fresh water. Round or rectangular posts, poles and sawn timber columns supporting permanent structures which are embedded in concrete or masonry in direct contact with earth or embedded in concrete or masonry exposed to the weather shall be treated
    wood. 'freatment shall conform to U.B.C. Standard No. 25-12, Tables Nos. 25-12-B through 25-12-F, for ground contact.
    **2. Under-floor clearance. **When wood joists or the bottom of wood structural floors without joists are located closer than 18 inches or wood girders are located closer than 12 inches to exposed ground in crawl spaces or unexcavated areas located within the periphery of the building foundation, the floor assembly including posts, girders, joists and subfloor, shall be approved wood of natural resistance to decay as listed in Section 2516 © 3 or treated wood.
    Accessible under-floor areas shall be provided with an 18-inch by 24-inch access crawl hole. Pipes, ducts and other nonstructural construction shall not interfere with the accessibility to or within under-floor areas.

Up a little early there buddy. :slight_smile:

Also covered here;

R317.1 Location Required

Protection of wood and wood-based products from decay shall be provided in the following locations by the use of naturally durable wood or wood that is preservative-treated in accordance with AWPA U1 for the species, product, preservative and end use. Preservatives shall be listed in Section 4 of AWPA U1.

  1. Wood joists or the bottom of a wood structural floor when closer than 18 inches (457 mm) or wood girders when closer than 12 inches (305 mm) to the exposed ground in crawl spaces or unexcavated area located within the periphery of the building foundation.

I don’t believe that height would fly with a VA or FHA loan.