CAVITY WALL TIES & RETAINING CLIP:
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Improve the effective thickness of a wall under load.
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Maintain the moisture break and thermal/sound insulation characteristics of cavity walls.
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Designed, manufactured and tested to the BS requirements of DD140 parts 1 and 2.
DD140 TYPE 3 CAVITY TIES:
General purpose ties suitable for cavity widths up to 75mm. Suitable for use in masonry cavity walls of domestic houses and small commercial buildings up to 15m in height, where the basic wind speed does not exceed 44m/s.
INSULATION RETAINING CLIP:
Suitable for use with all cavity wall ties. Used to hold insulation material back to structure.
SOUND RESISTANCE:
As stated within the Approved Document E 2003 - Resistance to the Passage of Sound - wall ties used in external and separating cavity walls have to have a minimum value of dynamic stiffness to reduce the transmission of airborne noise. Ties are separated into Type A and Type B.
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Type A: Can be used in separating walls and external walls subject to them also having the required structural capacity.
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They can be butterfly ties or other ties with a dynamic stiffness of less than 4.8 MN/cu.m
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Type B: Can only be used in external cavity walls subject to them also having the required structural capacity.
They can be butterfly ties or other ties with a dynamic stiffness of less than 113 MN/cu.m
MATERIAL:
Cavity Wall Ties: Stainless steel to BS EN 10088/2 Grade 1.4301.
Thickness as noted in table below.
Insulation Clip: Black plastic.
INSTALLATION:
For cavity walls with a leaf thickness of 90mm or more, unless otherwise specified place ties at 900mm centres horizontally, 450mm centres vertically and staggered where possible to a minimum density to be 2.5 ties per square metre.
Additional ties should be used at the unbonded vertical edges of an opening or at movement control joints. These should be placed 225mm from the joint, or opening, edge and at a maximum of 300mm centre to centre.
Ties should be embedded into each leaf by at least 50mm, however to allow for normal tolerances of cavity widths this is usually increased. When using insulation batts, it may be necessary to reduce the horizontal tie spacing to 600mm centres.
