The Two Part Tie is a standard-duty cavity wall tie designed to surpass the specifications of a Type 2 Tie for up to a 300mm cavity, as per PD 6697: 2010. It delivers unmatched water resistance across the cavity due to its unique connection feature, ensuring no water seepage from the outer to the inner leaf, even when installed with an angle of up to 5° in an unfavourable direction. This tie is suitable for use in a minimum mortar joint thickness of 10mm.
Often, constructing cavity walls with a large clear cavity can present challenges when the inner and outer leaves are built independently. Problems such as block overturning due to tie weight and maintaining a horizontal level may occur. The Two Part Tie addresses these issues effectively. Its two-part design enables an independent inner section to be embedded into the block or internal leaf, leaving a short slotted connection exposed for the attachment of the outer sections, which are installed during the construction of the outer leaf.
The inner sections of the Two Part Tie are available in standard lengths of either 170mm or 220mm to accommodate a maximum insulation board thickness of 70mm or 120mm respectively (alternative lengths are available upon request). An embedment of 62.5mm into the bed joint in both leaves is recommended. The outer sections are available in a range of lengths to suit cavities from 150 – 400mm.
Tie Density and Spacing
For walls with both leaves thicker than 90mm, the wall ties should typically be installed at a density of at least 2.5 ties/m². Grayson suggests spacing the ties at 900mm horizontal centres and 450mm vertical centres staggered at alternate courses up to a 300mm cavity. For larger cavities, a spacing of 600 x 450mm is recommended to maintain Type 2 load capacities.
Wall ties should be evenly distributed over a wall, except around openings or at an un-bonded panel edge, where the tie density should be increased to 225mm vertical centres within 225mm of the opening or edge.
The Two Part Tie demonstrates the best of standard-duty cavity wall tie design, offering outstanding performance and versatile application.