When you analyze dimension sheets from different quantity surveyors, you will realize that the order in which measurements are entered is quite different. The takeoff pattern varies between estimators. You will find an estimator with a clear and logical arrangement of quantities that can be easily followed and tracked. The other estimator, the one who will give you a headache has quantities that are hard to track and follow up. Most of the times, the data/takeoff entries created by this estimator has a pattern which is hard to understand or let alone figure out how the measurements were done. When we are talking about dimension sheets, we are not talking about paper sheets that you will find in a traditional Quantity Surveying firm e.g. cut and shuffle method, but we are talking about electronic dim sheets that you will use on a computer estimating program like WinQS or CostX. If you are still using paper sheets, then you are old-fashioned and behind technology. Computer-based electronic dim sheets can save your time and increase your productivity by a large margin, therefore you shouldn’t be using paper sheets in this age. Measurement has gone electronic and already there is powerful BIM takeoff software that can automatically generate quantities from digital 3D Architectural models.
With that said, if you are manually entering measurements on takeoff software, you should follow some basic principles that allow your dimension sheets to be easily understood. Anybody who reads your dimensions should be able to track the various parts of the drawings that were measured, for example when you are measuring walls, a rectangular building has at least four elevations. It might be a simple rectangle or it might be a complex design with several corners. In order to make your dimensions trackable, you have to enter them in a logical order. Start measuring your walls from point A to point B (corner-to-corner) to get dimension AB, then point B to point C to get dimension BC and so on. Do this successively until you have completed the perimeter, to the last point X. The last dimension should be XY. After completing the perimeter, your dimensions should look like this:
Wall AB – 2.100m
Wall BC – 2.400m
Wall CD – 4.000m
Wall DF – 3.200m
Wall FG – 2.000m
Wall GH – 2.500m
Wall HI – 4.000m
Wall IJ – 2.500m
Wall JK – 2.100m
On a digital dimension sheet, your dimensions should look like this:
You can clearly see how the walls have been referenced, the thickness and type of brickwalls i.e. Ext. (for External Walls) has been stated. When you copy the dimensions to another trade or location, you can easily see the walls that are being referred to on the drawings. It’s easy to check and track walls that have been measured, even if you are not the person who measured them.
|2.100||1||2.100||Ext Wall AB – 230mm|
|2.400||1||2.400||Ext Wall BC – 230mm|
|4.000||1||4.000||Ext Wall CD – 230mm|
|3.200||1||3.200||Ext Wall DF – 230mm|
|2.000||1||2.000||Ext Wall FG – 230mm|
|2.500||1||2.500||Ext Wall GH – 230mm|
|4.000||1||4.000||Ext Wall HI – 230mm|
|2.500||1||2.500||Ext Wall IJ – 230mm|
|2.100||1||2.100||Ext Wall JK – 230mm|
Compare the above dimension sheet with the one below. The dimension sheet below contains measurements which are hard to track or check against the drawings. The estimator literally made it hard to follow up the Dims. It’s not clear which walls have been measured and it will take a lot of effort to determine the connection and accuracy of the quantities against the drawings.