Safe Glass Balustrade Installation into a Timber Substrate
Wednesday April 15, 2026
Common issues with glass balustrade fixed to a timber substrate
Fixing a glass balustrade to a timber substrate has been a requirement from the beginning. However, the way that force loads pass through the glass and into the fixings has long posed a challenge. As a result, balustrade manufacturers have struggled to provide a reliable solution.
The key issue is how the channel is secured to the timber. Most installations would look to use lag bolts or ‘coach screws’ to fix the channel into the timber.
Research and development
At Pure Vista, safety and durability are a core focus. To support this, our team conducts extensive in-house testing for research and development. Our team performs the tests multiple times on the same installation. To research the timber fixing issue, we carried out line load testing using the lag bolt fixings.
In the initial line load test, the lag bolts passed; however, during the second and third tests, we discovered that the bolts were pulling out of the timber.
In response to timber’s popularity in construction, we worked on a method to provide a strong fixing that will last the lifetime of the balustrade. This led us to create the Timber Fixing Plate, a plate with fixing holes into the timber and a threaded sleeve to hold the channel. This proved to be an incredibly strong design, which, test after test, has no signs of fatigue.
How to install a glass balustrade to a timber substrate
New decking areas can be designed with the right-sized timber to accommodate the Timber Fixing Plate. Alternatively, existing areas can be bolstered up to suit.
Timber substrate requirements
The timber must provide an edge distance of 5 x the 6mm timber screws, resulting in a minimum required timber size of 130 x 150mm (W x H).
POSIglaze with Timber Fixing Plate Installation Guide
1. Drill the bolt holes
2. Position the Timber Fixing Plates
3. Screw the plates to the timber
4. Continue to install POSIglaze channel as normal
Installers can rebate squares out of the timber to recess the Timber Fixing Plates. Then lay the waterproof membrane over the top, and apply the BalconySeal® system to achieve a waterproof installation.
Tested and certified
We have tested the timber plates for use with domestic balustrades and balconies up to 1200mm high (0.74kN line load to BS 6180).
Find our test reports here.
Compatibility
POSIglaze
POSIone
