How to Install Small Enclosures
The following steps walk through the four main points of a typical field installation of an underground enclosure that is smaller than 24 inches by 36 inches.

Written by Rob Fox on November 28, 2018
Small underground enclosures, commonly called handholes or pits, can come in a variety of shapes and sizes. Enclosures house critical electrical, telecommunications, gas, and water service connections. Each installation and application is different, but there are common installation guidelines that when followed will help to minimize field damage and ensure longevity.
The following steps walk through the four main points of a typical field installation of an underground enclosure that is smaller than 24 inches by 36 inches. To ensure a successful installation, it is important to comply with federal, state, and local laws and any applicable building codes.
The Four Basic Steps
Carefully install the cover and do not drop it. Rough handling of covers during installation can cause the lip of the box to chip and can damage the cover. Ensure proper soil compaction so that surrounding soil does not sink over time. Crews can temporarily mark their completed enclosures with conduit stubs so they could quickly audit their finished job site.
Site plans might specify that a concrete collar is to be poured around the enclosure for cosmetic reasons, for extra security, or for additional strength. Begin by creating a form and adding gravel to the base. A cutaway view shows the layers below the concrete ring of an enclosure. The concrete apron should be a minimum of four inches thick, but can fill the space between the top lip of the enclosure and the gravel base.
When installing a high-security Quazite® lock box enclosure, first install the inner metal jacket and then lifts the outer polymer concrete box into place. Check for level as each part of the assembly is added. The installer should check the spacing of the box in relation to the floor. Pour concrete into the floor. Cover the boxes with plywood to avoid getting concrete on or in the enclosure during the pour. Smooth the concrete with a trowel, finish edges, and remove extra rock and concrete prior to curing. The concrete will need to cure and covers added to complete the installation.
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