Subgrade vault

A subgrade vault for providing an enclosed region to house utility connections, said vault comprising:

• a body having a peripheral wall with an upper end and a lower end, an upturned skirt around the lower end extending peripherally around the body;
• a plurality of buttresses interconnecting the peripheral wall to the skirt;
• an upwardly-facing rim extending around the upper end;
• a seat in said region depending from said rim, said seat comprising a re-entrant wall from said rim and an inwardly-extending flange, and a plurality of buttresses interconnecting said re-entrant wall and the inside of said peripheral wall;
• and
• a lid for closing said upper end, said lid comprising a top plate with an upper surface, and a plug depending from the lower surface of said top plate whereby to form an overhanging shoulder;
• said lid and body being formed of a moldable organic plastic material, said lid fitting in said seat with its shoulder bearing on the rim;
• locking means for releasably holding said lid to said body, said locking means comprising a lip on said flange, a fastener with a head, a shank and a thread on said shank, said shank being passed through an opening in said lid with its head against the lid;
• a U shaped clip with two arms pressed onto said lip with the said arms on opposite sides of it, aligned with said fastener, said clip being made of metal and forming a thread adapted to engage the thread on the fastener, thereby to hold the lid to the body.