Technical Snapshot

Issue: Planter Box Penetrations

Planter Boxes are considered a high risk in relation to water leaks, with constant presence of water and damp or wet soil.  

Combine this with the way penetrations are installed via coring, through the critical floor wall junction, and the potential for leaks is almost certainly to occur. 

HDPE irrigation pipes, which have a bonding issue with nearly all membrane products, should be avoided as the potential for leaks is almost certain to occur.

Penetration at the critical wall floor junction should always be avoided. If this situation occurs, a concrete hob should be installed allowing the membrane to be sufficiently detailed at a higher point, to eliminate the risk.

Pipe clamps should also be considered to create a positive seal to all HDPE pipes.

Incorrect

1. No collar or sealant of any kind is being used here.

AS 4654.2 – 2012 states that all penetrations must be properly secured, & “All pipes, ducts and vents should be located within a collar mechanically fixed to the substrate as an extension to the penetration.

A separate collar should be used for each penetration.” & “The membrane must have a minimum overlap of 75 mm onto the collar”

• All penetrations to be secured through a collar/sleeve through the wall, allowing a minimum membrane overlap of 75mm.
• The penetration must be clear of any critical points, such as the corner floor wall junctions, up high on the wall, just below the top of the soil level is ideal.
• Provide minimum clearance around the penetration on all sides of 50mm.
• Irrigation pipes must be secured separately to the collar/sleeve via a clamping collar. HDPE plastic due to the smooth surface creates a bonding issue with membranes, resulting in delamination.
• The hammering of these pipes turning on and off tears at any membrane. Membranes are not designed to secure pipes.

Correct