Careful and accurate measurements of each element of the landscape and external will ensure that the project will suceed

In order to measure and quantities correctly,  the following data is required; 

• Plans, sections and other relevant details of the work. 
• Specifications indicating the exact nature and class of materials to be used

An estimate is necessary to give the client a reasonably accurate idea of the cost to help  decide if the work can be undertaken as proposed or needs to be curtailed or abandoned, depending upon the availability of funds and prospective direct and indirect benefits. Landscape and external works are often let out on a lump sum basis, in which case the client must be in a position to know exactly how much expenditure he is going to incur on them.

1. Estimating Materials 
Measuring the works correctly ensure it is possible to determine what materials and in what quantities will be required for the work so that the arrangements to procure them can be made.

2. Estimating Labour
The number of workers who will have to be employed to complete the work in the specified time can be calculated from the estimate by devising a works programme. 

3. Estimating Plant & Machinery 
An estimate will help in determining amount and kind of equipment needed to complete the work.

4. Estimating Time
Having previous experience on a wide range of projects it is possible to estimate with a reasonable degree of accuracy the  length of time required to complete an item of work or the project as a whole. Whereas the importance of knowing the probable cost needs no emphasis, estimating materials, labor, plant and time is immensely useful in planning and execution of any work.