Project managers who’ve been around the block know that even the best-laid plans can go awry. Instead of letting a delayed task derail the entire project and disrupt delivery, those PMs use float to manage delays and steer the project to on-time completion. But what is float in project management? And how can PMs use float alongside various project management frameworks?
What is project management float?
Put simply, project management float is the amount of time a given task can be delayed without causing a delay in the entire project. But, there’s a little more to it than that. In fact, there are two distinct types of float that project managers use to manage task timelines: total float and free float.
Let's look at some of the distinctions between the two.
Total float
- The total amount of time a task can be delayed without affecting the final project delivery date
- Usually what PMs are referring to when they talk about "project float"
- Can compromise a project's final delivery date and is of more concern than free float
Free float
- The amount of time a task can be delayed without impacting other tasks in the path
- Referred to less often than total float
- Usually not a huge concern to project delivery
Benefits of float in project management
As you can imagine, project float — sometimes called project “slack” — is highly beneficial for project managers, particularly those who oversee large, complicated projects with multiple task paths. Of course, project float helps tremendously with resource management, scheduling, and keeping projects on track for a timely delivery. But float is also extremely valuable for PMs working with contractors and internal resource managers.
For example, by knowing precisely how much free float and total float a particular task has, you give your contractors more leeway to work with. This means they can optimize their schedule by choosing the best crew for the job, working as materials arrive, working in the best weather conditions, and avoiding overtime.
Similarly, internal resource managers benefit from the flexibility project slack provides. Instead of feeling pressured by tight, non-negotiable deadlines, project float gives them the breathing room needed to allocate resources in the most efficient manner possible.
How to calculate float in project management
Before you can calculate total or free float, you must first identify and map your project’s critical and non-critical tasks. Of course, the tasks that make up your critical path are dependent on one another. By definition, then, there will be no float in the project’s critical path. However, in complex projects that contain more than one task path, float will come into play in your non-critical paths.
With your critical and non-critical task paths identified and planned, it’s time to calculate your float. These can actually be calculated with a simple formula.
To calculate total float, subtract the task’s earliest finish (EF) date from its latest finish (LF) date. It looks like this: LF - EF = total float. Alternately, you can subtract the task’s earliest start (ES) date from its latest start (LS) date, like this: LS - ES = total float. Both of these formulas will give you the task’s total float.
Free float, on the other hand, is calculated by subtracting the task’s earliest finish date from its earliest start date. That formula looks like this: ES - EF = free float.
An example of float in project management
Let's look at a simple example of how float can arise in a project.
Imagine you are building an extension on the ground floor of your home, and you set a deadline of six months. In order to build the extension, the following tasks need to be completed:
- Laying the foundations
- Plumbing and electricity
- Plastering and painting
- Laying the floor
The plumbing and electricity cannot be installed until the foundations have been properly laid, which will take six weeks. However, in your project schedule, you have allocated eight weeks for foundations to be laid. This means that laying foundations can start two weeks after your project's start date without affecting the scheduled installation of plumbing and electricity. The float for laying the foundations is, therefore, two weeks.
How to use float for better project management
No matter your preferred project management framework or style, understanding total and free float can help you and your teams improve resource management, internal and external scheduling, and project delivery. The great part about float is that it can be implemented in just about every PM framework, including Agile, Kanban, critical path, PERT, waterfall, and more.
Of course, by leveraging a proven project management software platform like Wrike, you’ll have all the tools you need in one convenient place. Wrike’s interactive Gantt charts make it simple to see exactly where a project is at any given time while giving you insight into total and free float among your project’s tasks.
If you’d like to see exactly what Wrike can do for you and your project teams — and how float can help you get the most from your next project — start a free two-week trial today.
FAQs
What does float mean in project management? ›
Project management float, also known as “slack,” is the amount of time a project can be delayed before failing to meet a deadline. Usually, this time will depend on what tasks are involved and how much float each one allows.
What is an example of float in project management? ›For example, if you determine the earliest date your team can finish installing drywall is Sept. 10 and the latest date they can finish this task is Sept. 14, your total float is four days.
What are the three types of floats? ›Types of Float- Free Float, Total Float, Project Float.
How is float calculated in project management? ›Float Calculations
Formulas for calculating Total Float and Free Float are as follows: Total Float = LS – ES (it is also calculated by LF – EF)Free Float = Lowest ES of successors – EF. Free Float = Lowest ES of successors – EF.
The float is essentially double-counted money: a paid sum which, due to delays in processing, appears simultaneously in the accounts of the payer and the payee. Individuals and companies alike can use float to their advantage, gaining time or earning interest before payment clears their bank.
How do float values work? ›Integers and floats are two different kinds of numerical data. An integer (more commonly called an int) is a number without a decimal point. A float is a floating-point number, which means it is a number that has a decimal place. Floats are used when more precision is needed.
What does a negative float mean? ›Negative float, also known as negative slack, is a common concept in project management that refers to the amount of time that must be saved to complete a project on time. Another way of looking at negative float is the time beyond the scheduled completion date that a project or activity requires to achieve completion.
What are examples of float? ›A floating point number, is a positive or negative whole number with a decimal point. For example, 5.5, 0.25, and -103.342 are all floating point numbers, while 91, and 0 are not.
What is the concept of float analysis? ›The FLOAT Method is a five-step process that facilitates your ability to outline your project by (1) conceiving of a research question, (2) explaining how you locate, (3) organize, and (4) analyze a given data source, and finally, (5) transforming your findings into a visualization.
What is zero float in project management? ›When there is no extra time between activities, we have zero float, and it is considered a critical activity. A series of critical activities that are dependent on one another make up a critical path. If a critical activity slips and doesn't meet its deadline, it causes the project finish date to slip.
How do you know if a float is valued? ›
- In the function isfloat() , float() tries to convert num to float. If it is successful, then the function returns True .
- Else, ValueError is raised and returns False .
The triple constraints of project management—also known as the project management triangle or the iron triangle—are scope, cost, and time. You'll need to balance these three elements in every project, and doing so can be challenging because they all affect one another.
Is float and slack the same? ›Project float, also known as slack, is the amount of time by which a given task within a project can be delayed before it impacts the deadline for the project.
What are the advantages of float? ›There are a several physical benefits that floating has been shown to offer – including reduced pain, inflammation, reducing stress your body or immune system might be under. Floating promotes vasodilation, which means that your blood vessels dilate to allow better blood flow as well as ease high blood pressure.
When should I use float? ›float is mostly used in graphic libraries for high processing power due to its small range. double is mostly used for calculations in programming to eliminate errors when decimal values are being rounded off. Although float can still be used, it should only be in cases when we're dealing with small decimal values.
What is a good float ratio? ›What is considered a good low float percentage is subjective; traders have different preferences for float percentage. However, most traders look for a percentage between 10% and 25%.
Is higher or lower float value better? ›Low float is better to the majority, high float is only better if it's in the top 3 worst floats, collectors love them. how can you tell what skin value is?
How do you profit from a float? ›The term for that 'processing time' is known as 'float'. Businesses can profit on this float by earning interest on that money. Banks, for example, will lend your float money out to other banks and earn interest on it. In doing so, they make a profit from your transfer.
What are the 7 kinds of floating? ›- The Traditional Saddle Float. ...
- The Hammock Float. ...
- The Amazing Back Float. ...
- The Fitness Front Float. ...
- Standard (most common) Under the Arms Float with Thang Arms Extending Forward. ...
- Under the Arms Float with Thang Arms Extending Behind. ...
- The popular Lazy Lounge Float.
When a body floats in a liquid, the weight of the liquid displaced by its immersed part is equal to the total weight of the body. This is the law of floatation, i.e. while floating the weight of the floating body = Weight of the liquid displaced by its immersed part.
What are 5 things that float? ›
- Some items that float on water are listed below:
- Plastic bottle.
- Piece of paper.
- Piece of sponge.
- Piece of thermocol.
- Wood.
- Bamboo.
- Plastic ball.
Float, sometimes called Slack (float) , is the amount of time an activity, network path, or project can be delayed from the early start without changing the completion date of the project. Total float is the difference between the finish date of the last activity on the critical path and the project completion date.
What determines float? ›An object floats when the weight force on the object is balanced by the upward push of the water on the object. The upwards push of the water increases with the volume of the object that is under water; it is not affected by the depth of the water or the amount of water.
Why is it important to learn how do you float? ›Floating is a crucial part of learning to swim. When learning to swim, self rescue is an important piece. A lot of accidents at the pool happen when someone unexpectedly falls into the water. If they don't know how to float, they will mostly likely begin to panic which makes the situation even more dangerous.
What is a good low float? ›Investors typically consider a float of 10-to-20 million shares as a low float, but there are companies with floats of less than one million. Some larger corporations have very high floats in the billions, and you can find even lower-float stock trading on over-the-counter exchanges.
Do floats have to be positive? ›Floating point numbers are different from integer numbers in that they contain fractional parts. Even if the number to the right of the decimal point is 0 (or decimal comma, if your locale uses commas instead of periods), it's still a fractional part of the number. Floating point numbers can be positive or negative.
How much float does the critical path have? ›Historically, activities with zero float were defined as the critical path.
What are float types? ›The FLOAT data type stores double-precision floating-point numbers with up to 17 significant digits. FLOAT corresponds to IEEE 4-byte floating-point, and to the double data type in C. The range of values for the FLOAT data type is the same as the range of the C double data type on your computer.
How do you fix a negative float? ›Solution. With negative float caused by a Must Finish By date constraint, one solution to remove it would be to compress the project schedule. A few common methods that can be used to shorten the project duration while maintaining the project scope is to use either fast tracking or crashing.
What is total vs free float? ›Simply put, Total float is the amount of time that an activity can be delayed without delaying the project. On the other hand, free float is the amount of time that an activity can be delayed without delaying the early start of its successor.
What is minimum float? ›
Minimum Float IPO means the consummation of an IPO on an Approved Exchange in which the number of shares of Class C DTI Common Stock sold to the public equals or exceeds 10% of the outstanding DTI Common Stock calculated on a pro forma basis immediately following the consummation of such IPO.
How do you read a float? ›So, to read a float number from console, give the format and argument to scanf() function as shown in the following code snippet. float n; scanf("%f", n); Here, %f is the format to read a float value and this float value is stored in variable n .
How do you compare float values? ›To compare two floating point values, we have to consider the precision in to the comparison. For example, if two numbers are 3.1428 and 3.1415, then they are same up to the precision 0.01, but after that, like 0.001 they are not same.
What are 5 types of constraints? ›- NOT NULL constraints. ...
- Unique constraints. ...
- Primary key constraints. ...
- (Table) Check constraints. ...
- Foreign key (referential) constraints. ...
- Informational constraints.
Time, scope and cost: the three pillars of Project management.
What is time vs quality vs cost? ›The triangle illustrates the relationship between three primary forces in a project. Time is the available time to deliver the project, cost represents the amount of money or resources available and quality represents the fit-to-purpose that the project must achieve to be a success.
Who owns the float in a construction schedule? ›A float-allocating clause generally provides that the project's float is owned by the owner (or contractor) and that the contractor (or owner) or any other party is not entitled to any adjustment to the project completion date or compensation because of the loss or use of project float.
What is float vs lead? ›Float information is useful in resource allocation when there are resource constraints. Lead is used for accelerating start of tasks (fast tracking) for reducing project timelines.
Why critical path is the longest path? ›The critical path (or paths) is the longest path (in time) from Start to Finish; it indicates the minimum time necessary to complete the entire project.
What does float mean in business terms? ›Float: The float indicates how many shares are available for the general investing public to buy and sell. It does not include, among other things, restricted stock held by insiders. However, if insiders eventually sell their stock in the market, these shares become part of the float.
What does float mean in working? ›
A Float employee is defined as an employee who works a variable work schedule at multiple work sites or departments within or between facilities. A Regular Float employee is one who works a predetermined number of hours in a pay period but with no regularly defined work schedule.
What does float mean in a company? ›The term float refers to the regular shares a company has issued to the public that are available for investors to trade. This figure is derived by taking a company's outstanding shares and subtracting any restricted stock, which is stock that is under some sort of sales restriction.
What does float mean on a work schedule? ›Examples of Schedule Float in a sentence
Float or Slack in the Schedule Float or slack is the amount of time between the early start date and the late start date, or the early finish date and the late finish date, of any of the activities in the schedule.
What is considered a good low float percentage is subjective; traders have different preferences for float percentage. However, most traders look for a percentage between 10% and 25%.
What is a float example? ›Examples of integers are 0 , 1 , 2 , 3 and 4 . The float data type represents a floating-point or decimal number. Examples of floats are 0.1243 and 12.245 .
What's an example of float? ›Example Sentences
They floated the logs down the river. She floated gracefully across the stage.
A floating holiday is a benefit some employers offer employees in addition to vacation or PTO. Typically, it's a paid day off that is sometimes offered as a substitution for a public holiday. However, unlike a public holiday, a floating holiday may be used at an employee's discretion, taken on a day they choose.
What is a good float for a company? ›What is considered a good low float percentage is subjective; traders have different preferences for float percentage. However, most traders look for a percentage between 10% and 25%.
Is high float good? ›Generally speaking, high-float stocks are usually best for long-term investing strategies. If you're looking for potentially substantial gains in a short timeframe, then low-float stocks can be something to look into.
What does it mean when a company has a low float? ›Low float stocks are those with a low number of shares. Floating stock is calculated by subtracting closely-held shares and restricted stock from a firm's total outstanding shares. Closely-held shares are those owned by insiders, major shareholders, and employees.
What is considered a low float? ›
Investors typically consider a float of 10-to-20 million shares as a low float, but there are companies with floats of less than one million. Some larger corporations have very high floats in the billions, and you can find even lower-float stock trading on over-the-counter exchanges.
What does low float mean? ›A low float stock is a stock with a relatively small number of available shares on the market. That doesn't mean these companies don't have a lot of shares. They often do. But they're usually closely held by institutional investors, employees, or other major stakeholders.
Do you get paid more to float? ›Float pool nurses that are paid higher rates receive, on average, 15% more than their permanent counterparts.
Who owns float in a schedule? ›A float-allocating clause generally provides that the project's float is owned by the owner (or contractor) and that the contractor (or owner) or any other party is not entitled to any adjustment to the project completion date or compensation because of the loss or use of project float.
How do you calculate float in project schedule? ›To calculate total float, subtract the task's earliest finish (EF) date from its latest finish (LF) date. It looks like this: LF - EF = total float. Alternately, you can subtract the task's earliest start (ES) date from its latest start (LS) date, like this: LS - ES = total float.