Cost Loading your schedule and Earned Value Analysis
I know that many people consider cost loading a schedule and then tracking those costs as magic, which can only be done by scheduling experts and to get there you will need to spend a lot of time and energy. And this is true well it was true. until now.. because now I am going to explain how it is done in 1-2 paragraphs....
Okay the first thing you need in order to track your construction cost performance and cost load your construction schedule is a detailed construction schedule. The more detailed your schedule is, the more refined your comparisons will be. After having all of the construction activities, plus non construction activities like scaffolding, protection of existing etc... in your schedule, and you assign all the durations and relations between those activities, you are ready to cost load your schedule.
Cost loading of schedule can be done in different ways or the combination of them. You can assign duration based rated costs, material costs, one time cost items or the total of these to any activity. These three things I just wrote are called your resources, assigning resources. A resource, by definition, can be used for any other activity too. In addition to assiging resources, you can also add a fixed cost to the activities. In some cases, adding resources can be omitted altogether and you only give fixed costs to your activities as a lump sum cost of that item to cover everything for that activity.
After you are done with adding all these, the scheduling software you are using will add the costs of all these and come up with a total cost of that activity for that instant. In MS project, this is to Cost column for instance. So in other words, even if you assign just lump sum costs to activities, do it at the fixed cost column. And MS project will calculate the cost for you in cost column. Cost column is like a result column of all costs. Don't enter directly in there, it is not good practice.
After you assign all costs and resources and come up with the costs for each activity, you can then look at the cumulative costs over time. You will need to switch views for that. In MS project that view is called the Task usage view. In task usage view, simply add the cumulative cost to the display rows, and it will show you how that cumulative cost accumulates over time. Then all you need to do is to copy paste the progressing dates and the cumulative cost to excel and come up with a nice S Curve, which shows you your total spending over time. MS projecyt can also draw this graph by itself but I find copying and pasting into excel better way as I can tweak the format of the graph as I want.
This was the first phase of your cost tracking, which was done at the beginning of the job, before there are any actual costs incurred. At this stage, do not forget to save a baseline of your schedule. This is very important for tracking purposes for later.
The second phase is, when your job starts and you start to have some real data in your hand. After you get your real data, you will start to enter those in your actual columns. You can either enter the data to your actual % or actual work or remaining work columns. No matter what you do, it is not different just a matter of how you get your data. But most cases to enter actual work remaining can be considered entering in a more healthy way as the duration remaining may not represent the true work remaining sometimes. When you start to update you will have durations that are different than original durations for some activities. This means that your planned vs actual will not be the same. This is when you do your earned value analysis, where your actual performance vs budgeted performance can be compared. For instance lets say you were planning to spend 100 dollars in 5 days for an activity but on your 4th day, you already spent 120 dollars and there are 3 days of more remaining work. Your planned vs actual earning are different here and you will need to calculate or rather you will have your scheduling program calculate budgeted cos of work planned, vs budgeted cost of work performed and actual cost of work performed. You can find a lot of articles on the net about EVA, but dont forget that the main principle is what I just wrote. That part is more planning rather than scheduling so I will not go into details of it here.