Please note: This third edition of TR34, published in 2003, has now been superseded by the fourth edition published in August 2013. The third edition may still be cited in contract specifications.
Table 4.2: Permissible limits on Properties II and IV in free-movement areas.
|Floor Classification||Typical floor use||Property II limit
|Property IV limit
|FM 1||Where very high standards of flatness and levelness are required.
Floors to FM 1 classification may need to be constructed using long strip methods. See Section 2.2.3.
|FM 2||Buildings containing wide aisle racking with stacking or racking over 8 m high, free-movement areas and transfer areas||3.5||5.5||8.0||12.0|
|FM 3||Buildings containing wide aisle racking with stacking or racking up to 8 m high.
Retail and manufacturing facilities
In assessing the surface regularity of free-movement areas, a sample of points on the floor is surveyed, as it is not practical to survey the infinite number of combinations of points on the floor. Unlike in defined-movement areas, it is not necessary to control every point with precision as MHE is generally operating with loads at low level and there is minimal risk of collision with storage racking at high level as a result of the floor being uneven.
Data analysis and permissible limits
The survey data is analysed and compared with the permissible limits for Properties II and IV given in Table 4.2.
In speculative construction, the developer is advised to build to as high a standard as possible. Surface regularity specification FM 2 (Special), see Table 4.4, is suggested to reduce the amount of grinding required for Category 1 use once the defined-movement areas have been defined.
Table 4.4: Permissible limits on Properties II and IV in floors for possible conversion to Category 1.
|Floor Classification||Floor use||Property II limit
|Property IV limit
|Floor for possible conversion to Category 1 defined movement||3.0||4.5||6.5||10.0|
The floor is non-compliant if:
Measuring Property IV (and Datum check) using an Optical Level and Parallel Plate Micrometer, taking readings from an Invar Staff to 0.1mm.
Measuring Property II on site with our Property II Meter.
The Concrete Society’s TR34 Free Movement (4th Edition) Classifications
The Concrete Society’s TR34 Free Movement (3rd Edition) Classifications
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