The Glass Railing Specialists

POSIglaze Base-Fix Drain Block 5mm Shim

The patented plastic drain block raises your channel above the fixing substrate to create water drainage channels. Simply align the grooves in the drain block with the channel and then lay the channel over the drain blocks. Read the full installation guides here.

As a maximum, drain blocks can be stacked to a height of 20mm before being filled with sealant. The 5mm black must be used with the 10mm block to enable the sealant to be pumped in.



Can be used on POSIglaze Balcony Seal for base Fix Channel.


POSIglaze is compatible with glass thicknesses between 12mm – 21.5mm.


Drain blocks are available for use with the POSIglaze channel. We stock two variations of POSIglaze drain block, a Base Drilled Drain Block and a Side Drilled Drain Block to be used alongside base or side fix channel.


Base Drilled Drain Block Dimensions:
H = 5mm


1x 5mm Plastic Shim


POSIglaze base fix and side fix require different drain blocks, please ensure you select the correct product.


Excluding VAT


This website uses cookies to ensure you get the best experience. For further information read our privacy policy.