SVI have developed an annular gap sealing technique for mains which lie underneath a private property, for example, under a garage or under a conservatory. This innovative process can be deployed by our Contract Service team and helps to protect the gas main and prevent surface slump.
The annular gap sealing technique uses our Flowstop foam kit in conjunction with one of our bespoke entry systems and can be injected from a remote location allowing application in hard to reach places.
Prior to the job being carried out our Contract Service team will perform a CCTV inspection to ensure there are no unforeseen obstacles in the way. The metallic main where the annular gap entry system will be fitted will then be cleaned before insertion of the annular filling.
Important Information: The Overbuild System is only available on properties which have been fully assessed and meet the strict Overbuild criteria as set out by the GDN’s.
Features and Benefits
- The system is transportable through a customer’s property
- The system fully fills the annular space beneath the property and by at least 2m outside of the building line
- Injection of the sealant can be accomplished through varying connections to the annular space including via a UPT system, fabric end seals or a flexible fabric entry system
- It realises an increased ability to plan ‘Live Mains Insertion’ projects with built over properties within the vicinity
- It enables the total decommissioning / abandonment of annular spaces beneath customer properties
- The technique is deployable from remote, less sensitive areas within the customer’s private boundary
- It reduces disruption to the public by abandoning annular spaces without the need to fully excavate them or carry out expensive and disruptive diversion work
- Cost benefits can be made due to the ability to plan ‘Live Mains Insertion’ projects without the need for expensive diversion work that the Overbuilds System avoids
- All waste produced by the technique will be removed by SVI after the operation is completed