ABN: 83 155 600 749

LIC: 247579C

Original Specification

The  building contractor, Lahey Constructions, was to demolish two buildings in a row of terraces and so additional support was required to be provide lateral wall restraint  to the remaining buildings either side. Helicrete was chosen to carry out the work and tied every second joist to the wall as there wasn't any current positive connection detail to the joists. The ties used were Helifix Bow Ties (8mm x 295mm). The work was carried out over several hours to the satisfaction of the foreman allowing for the schedule of work to proceed as planned.

Engineer's original design, believing the joists were built into the wall and their ends over lapped side by side.

Investigation by Helicrete on site found out the joists were in fact butted up end to end with each other and the original installation of Helifix bow ties was not possible. The consultant engineer then specified the the new detail which is effectively detail RB06 but the ties were installed in reverse from the outside-in.  

​​Wall Restraint 

T: 02 4308 9901

M: 0406 588 585

The need for restraining walls is quite a common one. This can be due to several different reasons and one of the more common ones being the lack of lateral restraint when the building was first built. Other reasons may be from changes or alterations to a buildings usage, such as removal of internal bracing walls. Demolition and construction of adjacent buildings can cause the disturbance of walls and their foundations. Vibrations from earth moving equipment, undermining of walls or poorly temporarily braced walls are other factors. When a wall is built their is a direct relationship between the thickness of wall and it's height, slenderness ratio. The ability of the wall to stay upright above a certain height requires support by another means, this is usually affected by tying the walls (Leafs) to each other in a cavity construction, and in the case of a solid brick wall to other elements such as floor joists, ceiling joists and the roof structure. As can be seen in the video and photos above, the floor joist ends were built into the walls relying only on the friction of their bearing onto the wall and surrounding bricks to hold them in place. This is rectified by the installation of the wall ties. 

Click Thumbnail For Larger Image of Repair Detail