D400 Gully Grating assemblies with compatible Gully Chute Connectors

This image illustrates the finished ironwork installation without road surfacing strata, but with intermediate bedding mortar (shown red) and supporting mass concrete foundation materials in place.

Note: The above illustrates a conventional BS EN124 Group 3 location which allows a 3-flange gully grating to form a close abutment with a concrete kerb line.

In order to decide the most appropriate construction sequence for a given site, the following factors should be taken into account:

• The top face of the Gully Grating is intended to align flush with [or not lower than 6mm below] the intended surrounding finished surfacing.
• The overall depth of installed ironwork will be the sum of;
  • the overall depth of the two ironwork products stacked one on top of the other.
  • plus, an additional [minimum] 10mm bedding material thickness between the two ironwork products.
  • plus, the depth of mass concrete foundation needed underneath the Gully Chute Connector.

Note: Mass concrete supporting the Gully Chute Connector should ideally be a similar grade/strength and thickness as that used for bedding of the adjoining concrete kerbs.

• The Gully Chute Connector has a rear outlet spigot invert depth of c.178mm.

• The Gully Chute Connector is intended to be supported on its underside by mass concrete which should extend past its plan profile to provide full support to the intended overlying Gully Grating. The visible vertical faces of the concrete foundation may be finished vertically or battered.

• The Gully Chute Connector has a rear outlet [male] spigot suitable for connection to 150 or 160mm I/Dia [female] socketed pipework or the like and should be orientated to suit the intended pipework.

Note: When fitting the pipework (etc.) to the spigot, clean and then coat the spigot with a compatible lubricant to help prevent damage to the pipe fitting’s sealing element.

• Highway brand Gully Grating frames and compatible Gully Chute Connectors contain industry-standard BS7903-profiled large lifting keyway features for manual or mechanical lift, as appropriate.
• The bedding material placed between the Gully Grating and Gully Chute Connector is intended as an adhesive, structural, adjustment layer and should also envelope the top of the Gully Grating flange to a depth of >10mm. A Polyester Resin mortar type is recommended for this purpose. E.g. Wrekin Unipak.

Where hinged, ensure that the Gully Grating itself opens in the direction of traffic (so that, if left open, a traffic strike will close it). If the Gully Grating is not supplied hinged in the correct direction, remove the 2nr hinge pins and relocate them to the desired position.

• Allow all bedding and site mixed concrete materials to fully cure before allowing vehicles to traffic the ironwork.

In situations where the finished ironwork installation is likely to become exposed to construction-type or other damaging traffic types prior to its intended service application, ensure that it is protected by the temporary fitment of one of the following:

• Armadillo Ironwork protection (where available)
• Conventional Road Plates
• Other methods of protection

Note: Trafficking of the finished installation must not occur until the bedding, structural materials and adjacent surfacing have fully cured and any necessary temporary, pre-service protection is in place.

In general, cast iron products require little routine maintenance during their lifetime when exposed to their normal UK service environment. For further information, see Wrekin’s ‘Maintenance of BS EN124-2 Ironwork’ document.

For specific guidance on the assessment of an installation’s service condition, refer to the WRc Inspector’s Guide to Street Ironwork for the UK Water Industry CP373a/P8669.