This article explains fall protection options for a Stonebloc wall.
Balustrades and Fencing
Where a wall height is, or greater than, 1m high fall protection is required. While Stonebloc does not endorse any particular balustrade solution, we do provide a number of generic wall designs to support multiple balustrade options which comply with relevant regulatory codes.
Two factors play an important role in the ability of a Stonebloc wall to support top and rear mounted balustrading. The height of the post, and the distance between posts.
The height of the post determines the lever action on the block. The higher the post, the more reinforcing required. For the purposes of Stonebloc generic designs the maximum allowable post is 1.1m from the top of the wall. This height is the regulatory minimum required for fall protection. The distance between posts determines the amount of force each post exerts on the wall. The shorter the distance, the less the force exerted. For the purposes of Stonebloc generic designs two spacing options are considered 1.6m spacing, and a maximum of 2.4m spacing. The table below displays the force differential between the two spacing options;
|
Line Load |
Post Spacing |
Load/Post |
|
|
160mm |
0.9kN |
|
2400mm |
0.6Kn |
There are three balustrade mounting options available with a Stonebloc retaining wall:
- Top Mounted - where the posts are bolted directly to the top of the wall.
- Rear Mounting - where the posts are bolted directly to the back of the wall.
- Separated Fencing - where the posts are physically separated from the wall.
Top Mounted Balustrades
Stonebloc is one of the few retaining wall solutions which provide for balustrading to be top mounted. In order to support top mounting, the blocks do need to be tied together with brackets. The brackets need to be stainless steel in order to provide sufficient corrosion resistance to meet council requirements for consent.
Rear Mounted Balustrades
balustrades without the need for reinforcing clips, where the height of the balustrade above the top of the wall is no more than 1100mm high, and the spacing between the posts is no greater than 2400mm.
The Stonebloc wall design supporting this balustrade mounting requires the posts to be fixed to a minimum of two different blocks. The exact fixing specifications should be provided by the balustrade/fence supplier.
Separated Fence
This is the most common fencing/balustrade solution for retaining walls. The fence posts are concreted in place behind the retaining wall. As the fence is physically separate from the retaining wall there is no need for the wall design to consider supporting the fence design.
When selecting this option, remember to consider the wall profile - in some cases the fence posts will need to be offset a minimum 850mm from the front face of the wall.
Fixing Detail for Rear Mounted Balustrade
Bracing Detail for Top Mounted Balustrade
Top mounted balustrades require stainless steel clips to be installed on the back of the wall in order to tie the top few rows of blocks together.
Standard brackets used are BS65 for the I Clip, and BS55 for the L Clip. Both the brackets are supplied by Envirocon and have product codes in Hubspot with up to date pricing.