Enclosures sized smaller than 24” x 36” can be safely and securely installed by following these four simple steps.
Site Selection
Select an appropriate site or location that is suitable for an underground enclosure. Consider the following:
- Slope — Level is ideal, but some grade is acceptable depending on soil conditions and expected drainage.
- Existing underground utilities — Call 8-1-1 and avoid all existing lines
- Traffic — Select the enclosure type and ANSI/TIER load rating based on application.
Excavation
- Excavate six inches to one foot larger than enclosure size.
- Excavate six to eight inches deeper than enclosure height.
- Cover bottom of hole with six-inches crushed rock.
- Level gravel prior to setting enclosure.
Placement
- Remove cover from box.
- Manually position box on leveled gravel in bottom of hole.
- Adjust for level or to match grade.
- Trim/prepare any incoming conduit paths.
Backfill
- Begin backfilling around perimeter of box and manually tamp, every six- to eight-inches of backfill. Proper backfilling will minimize settling and potential frost heave of the enclosure.
- Where ribbing exists on exterior of enclosure, carefully work backfill into voids and tamp.
- Bring backfill to desired grade. Enclosures Reference Guide
