WSRB Blog

What is an Open Foundation? | WSRB Blog

Written by Robert Lacy | March 13, 2018

Have you ever received an WSRB inspection and noticed the building had an “open foundation?” What the heck is that? Because many people are unfamiliar with the term, we’ve made it the topic of this blog post.

Open foundations feature openings that go beneath the building, generally into a crawl space or other open space beneath the floor joists. Keep in mind that open spaces beneath a second story are not considered the same as an open foundation.

Open foundations, like this one, can create property risk

 

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Other than those under docks, wharves and piers, open foundations are generally avoidable. Closing them helps protect the building from fire risk and improves its overall safety.

Open foundations can appear in a number of ways:

  • A masonry wall resting on a combustible foundation that rises above the low-water mark.
  • A trailer-type structure on stilts without protection, running along the bottom of the building between the floor and the ground.
  • A building with an unprotected opening into a basement or crawlspace.

Open foundations are a concern for a simple reason

Anyone walking by can flick a cigarette or other burning material into the open space. A smoldering fire in a crawl space can go unnoticed and easily grow into a larger fire that can work its way up the wall joists and across the underside of the floor. Open foundations also create a potential for arson or other dangerous activity because burning items can easily be thrown into the crawl space.

Open foundations can generally be closed easily, reducing risk.

Also, open foundations are simply a nuisance. They look like easy places to throw trash, which can pile up in the building and attract more refuse. This debris can serve as fuel for a potential fire or make the building a target for vandals.

How to reduce open foundation risk

It’s not hard to take necessary precautions. First, take a quick walk around the outside of the structure. Take note of any holes or chutes into a crawl or below-floor space, then put up chicken wire or other protection to cover the opening, making sure it’s secured on all sides.

If a trailer is being held up by combustible posts or foundations, attach chicken wire or trellis along the outside perimeter to enclose the area, and make it difficult for people to throw burning materials underneath.

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