TR34 2003 3rd Edition Free Movement Floor Classifications
According to TR34 2003 (3rd Edition) Free Movement floors and associated construction tolerances are not intended for very narrow aisles, where a defined movement specification should be used.
The surface regularity is controlled in two ways;
1. Appropriate flatness (Property II)
2. Appropriate levelness (Property IV)
Each of these properties has got limits which have to be achieved to ensure that the floor as a whole with all its static and mobile equipment can operate safely and efficiently.
Flatness Explained
Flatness is surface regularity characteristics measured between two points over a short distance, typically 300mm.
To control flatness (the change in elevational difference between two consecutive measurements 300mm apart of each other) TR34 2003 specifies Property II limits, which can be found in table 4.2 and 4.4 of TR34 2003 3rd Edition. These are also shown in the table below.
Property II (flatness) is measured using specialist digital equipment DABROS Digital Property F Recorder with accuracy of 0.1mm, and all measurements are taken at 10mm intervals. The DABROS Digital Property F Recorder is pulled along the randomly chosen grid lines on the Free Movement area. The survey data is continuously collected by a phone connected via Bluetooth with the device and later analysed using our specialist software, which generates graphs for each individual survey run.
Below graphical illustration of how the property II is measured.
Floor classification | Typical floor use | Property II limit (mm) | |
95% | 100% | ||
FM 1 | Where very high standards of flatness and levelness are required. Floors to FM1 classification may need to be constructed using long strip methods. | 2.5 | 4.0 |
FM 2 (Special) | Floors for possible conversion to Category 1 defined-movement. | 3.0 | 4.5 |
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 |
FM 3 | Buildings containing wide aisle racking with stacking or racking up to 8 m high Retail and manufacturing facilities | 5.0 | 7.5 |
Levelness explained
Levelness is surface regularity characteristics measured over a long distance, typically 3m. Also, any point on the floor has to be within +/-15mm from a datum, which is usually set at the start of the construction of a building.
To control levelness TR34 2003 specifies Property IV limits, which can also be found in table 4.2 and 4.4 of TR34 2003 3rd Edition. These are also shown in the table below.
Floor classification | Typical floor use | Property IV limit (mm) | |
95% | 100% | ||
FM 1 | Where very high standards of flatness and levelness are required. Floors to FM1 classification may need to be constructed using long strip methods. | 4.5 | 7.0 |
FM 2 (Special) | Floors for possible conversion to Category 1 defined-movement. | 6.5 | 10.0 |
FM 2 | Buildings containing wide aisle racking with stacking or racking over 8 m high, free-movement areas and transfer areas | 8.0 | 12.0 |
FM 3 | Buildings containing wide aisle racking with stacking or racking up to 8 m high Retail and manufacturing facilities | 10.0 | 15.0 |
Limits explained
Each of the properties (Property II and Property IV) have 95% and 100% limits.
In order for the floor to comply with any required classification following criteria have to be met:
1. No more than 5% of all Property II measurements (all survey lines combined) exceeds the 95% limit of the required classification
Example:
FM2 (Special) – 95% of all measurements combined must have values of max. +/-3.0mm or less in order to comply with the required classification.
2. No more than 5% of all Property IV measurements (all level differences between adjacent points) exceeds the 95% limit of the required classification,
Example:
FM2 (Special) – 95% of all level differences between adjacent points must have values of max. +/-6.5mm or less in order to comply with the required classification.
3. None of all Property II measurements in any survey run exceeds the 100% limit of the required classification,
Example:
FM2 (Special) – 100% of all measurements recorded must have values of max. +/-4.5mm or less in order to comply with the required classification.
4. None of all Property IV measurements (all level differences between adjacent points) results exceeds the 100% limit of the required classification,
Example:
FM2 (Special) – 100% of all level differences between adjacent points must have values of max. +/-10.0mm or less in order to comply with the required classification.
5. None of the Property IV result of the floor is outside ± 15 mm of datum.
Non Compliance
Where more than 5% of all the measurements are greater than the 95% limit (for both Property II and Property IV) or where any measurements are greater than the 100% limit (for both Property II and Property IV), TR34 2003 recommends that the individual measurements are examined in detail to determine their significance before any remedial actions are taken. Minor variations are unlikely to affect the performance of a floor (disadvantages of this can often outweigh the advantages) and remedial actions such as surface grinding will affect the appearance of the floor.