The HydroHALT Sealing System & IVD-Merkblatt Nr. 3-2 Ausgabe Nov. 2014

In Merkblatt Nr. 3 – 2, the core focus is new concepts (other than injectable sealants) in the form of butyl adhesive sealing strips. Merkblatt Nr. 3 – 2 is a supplement to Merkblatt Nr. 3 – 1, consequentially both documents are related and must be considered relevant in respect of the HydroHALT Sealing System.

The HydroHALT Sealing System is a joint sealing technology not currently recognized by Merkblatt Nr. 3 – 1 or 2 which documents are technically prejudiced to the continued installation of traditional butyl adhesive sealing strips.

The HydroHALT Sealing System was developed to overcome the problems associated with the use of such butyl adhesive sealing strips. Examples of the installation limitations and technical problems associated with the use of butyl adhesive sealing strips promoted in Merkblatt Nr. 3 – 1 & 2 that HydroHALT overcomes are:

1. Merkblatt Nr. 3 – 1 & 2 promotes the use butyl adhesive sealing strips that can only be installed during the installation of a shower tray or bath. The HydroHALT Sealing System can be installed:



During installation of a new shower tray or bath

Fig. 2

Over shower trays and baths with up-stands


Fig. 3

Into an existing ledge/wall joint

Fig. 4

Over an existing ledge/wall joint



2. Merkblatt Nr. 3 – 2 promotes the use of a 30mm wide butyl adhesive bed which requires the shower tray side walls to be at least 30mm high. HydroHALT can be installed with low profile shower trays as low as 6mm.

Fig. 5



3. Merkblatt Nr. 3 – 2 recommends the ‘pleating’ of strips to solve the problem of rounded shower tray and bath side wall corners. The HydroHALT strip extends 100% into all wall corners because it is firstly bonded to the shower wall and not the side wall of shower trays or baths.

Fig. 6

Hydrohalt fits tight into corner

Fig. 7


4. Merkblatt Nr. 3 – 2 recommends the use of sealant isolating material to address problem of sealants reacting with the butyl adhesive. In the HydroHALT Sealing System butyl adhesive has been eliminated.



5. Merkblatt Nr. 3 – 1 Fig. 9 and Merkblatt Nr. 3 – 2 Fig. 4 both highlight the cavity formed over the butyl adhesive upper face after installation. This cavity creates perimeter ponding that continually feeds capillary action up the shower walls. In the HydroHALT System, the exposed upper face of Sealux-N throws water away from the walls.

Fig. 8

Fig. 9


Cut Protection

Fig. 10

Fig. 10

IVD-Merkblatt Nr. 3 – 2 part 4 paragraph 2 states that cut protection for waterproofing systems is currently not fully regulated due to technical feasibility – and no more !

The inferred implication is that cut protection will be fully regulated when technically feasible.

Cut protection may be advantageous in respect of butyl adhesive sealing strips where an unrestricted void exists between the ledge and the strip upstand (see Figure 8).

Cut protection is not required in the HydroHALT sealing system because the sealant extends over the ledge.

What is required is normal care and attention in respect of the task in hand.

When replacing the sealant between the tile and ledge, the blade is set to the minimum depth required to remove the tile/ledge sealant and no more.