Therefore, the guidelines do contain more choices than are required for any specific project. If some aspect of your project is relatively simple and straightforward, keep the structure of the CAD data for that project segment as simple as you can.
Remember: your goal is to keep your project data structure as simple as is appropriate for your project. One bit of advice about text styles—use the fonts that come with your system wherever you can and avoid non-standard fonts.
If you develop cus- tom fonts or buy fonts from a third party and then incorporate them into your drawings, you may have trouble passing your data files to other team members. There are ways around these problems, but why complicate things unnecessari- ly? Caution Avoid fancy or custom text fonts. Keep it simple—stick with the standard fonts that come with your CAD system and you will avoid unnecessary coordination prob- lems. One of the most important ways you can improve your productivity with CAD is to let it help you avoid drawing things more than once.
A library is the most obvious way to do this. Caution Develop a CAD library. It will improve your productivity and make your work more consistent. Develop a basic library when you first get your system, then expand your library with every project.
Use your library. Start your library with: S Standard sheets with: S borders and title blocks S parameter settings for units, scales, text heights, etc. When closing out a project, comb the files for material that should be added to your library. Before drawing anything new for the current project, consult your library for guidance or for material that can be re- used, either as it is stored or with minor changes.
Make library development an ongoing effort in your company. In the same way, you may be reluctant to pass your own design files back to the general contractor or on to the project owner. The reason for this reluctance is often a concern about liability for the contents of the files.
For a more detailed discussion of these concerns, see Liability on page A. In such projects, the team is assembled earlier in the project. Design of the overall project design and sub-systems must be carefully coordi- nated in such situations to keep an air distribution system clear of structural members or light fixtures, or example.
When this happens, it is critical to document all exchanges, to insure that all parties understand just what information is being exchanged and just what stage of completion the exchanged files represent. Internet-based project collaboration service portals now offer unprecedented new opportunities to exchange information in a timely, responsible, and efficient manner. Test out these new technologies on smaller projects before committing them to larger projects where you have more at risk.
Ask the tough questions about Internet security to safeguard your intellectual property. Explore the full scope of the cost of these services, so you do not experience any rude surprises as the size of your project document and drawing database grows. Admittedly, it is always important to proceed with caution into new arenas, however it may be equally important to avoid letting excessive caution prevent you from preceding to find out what these new technol- ogies can do for you.
This can save you significant time and effort. It can save you money and help you finish your drawings just that much sooner. When you receive CAD files from other project team members, though, you must determine whether: S the files reached you on schedule S the files were prepared according to the Project CAD Specification S the files contain the information you expected S the files contain up-to-date information S whoever provided the files warrants that the information contained in them is accurate Once you receive information from the designer or the general and then do your own CAD work, you may have to pass your CAD files on to other parties.
You may have to transfer your files to the general who may plan to use them himself in a project scheduling or project management system or may pass them on to the project owner. You may have to pass your files directly to the owner. Caution Understand your contractual relationships within the project team. Who do you have a contract with?
Who has a contract with you? What do the contracts re- quire? Consider these relationships when you receive a request to deliver electronic files If you do have a contract with someone who makes such a request, determine how the request fits into what the contract requires you to do. If you do not have a contract with the requester, you may not be required to deliver anything.
If you pass your CAD files on to other project team members, be sure you completely document each submittal as described previously. In doing so you may be voluntarily assuming liability that is not included in your contract. Deliver your CAD files only when you are required to do so by a contrac- tual relationship or a legal requirement.
Understand your contractual relationships. Who is your contract with? What does your contract require you to deliver? Suppose you are the air conditioning contractor and that your contract is with the general contractor.
What if the plumbing contractor asks for your CAD files? You do not have a contract with the plumbing contractor. You are not receiving any compensation for working with him. Anything you give him is a gift and by giving it you assume an undefined liability for the content of what you deliver. You are assuming liability that is not required by any written agreement and you are doing it for free! You have no contractual obligation to the plumbing contractor and you should not give him anything.
Suppose that in the situation above the general contractor asks you to deliver CAD files to a third party. You may not be required to make the requested deliver, but you want to be a responsible team member and keep the project moving forward.
You will probably end up making the delivery as requested, but here are some suggestions: S Determine whether your contract requires you to make the delivery.
S If the delivery is not required, consider requesting additional compensation. After all, you will be doing work that was not included in the original agreement. S Deliver the requested material to the general contractor and let him pass it on to the third party. S Document whatever you deliver. Pay special attention to describing what you deliver and its state of comple- tion at the time of the delivery.
Do not assume responsibility for updating the recipient on changes that occur after delivery. This might include: site survey data, drawings of existing building conditions in the project area or existing adjacent structures, or drawings from previous project phases preliminary designs, for example.
Caution Will you be receiving electronic files from the project owner or other project team member? Check these files carefully and determine how you will use them before you agree to a price or schedule for your work. Owners usually provide this information to prevent the project team from having to gather the information themselves.
Owners often expect that their providing these files will save work for their project team and, thus, reduce design fees. Sometimes this works out.
Often it does not. First, what is the condition of the electronic files? S Are they well organized and were they executed carefully? S Are they compatible with your CAD system and easy to read? S Do they contain information you can use? S Do they contain a lot of other information from which you will have to extract the useful parts? S Does the value of the information contained in the files exceed what it will cost you to use them? Second, is the information contained in the files accurate?
S Can you rely on the information without having to go to the field and verify it? S Is the party who prepared the files available to answer your questions about them? S Does the owner warrant the accuracy of the information? Few owners will make such assurances, but without such a warranty, you may have to field verify everything in the files.
This makes the files much less valuable. An owner may require you to deliver files at the end of the project for several reasons: Project Archive. The owner may want to keep CAD files as a project archive.
An electronic archive is more volatile than he may understand. Electronic files can become inaccessible and unusable through deterioration of magnetic me- dia or through changes in hardware or software. Your best protection is to educate the owner before the project starts.
If you do not have direct access to the owner, you can only work through channels to spread this information. Use in Later Project Phases. The owner may want to use the CAD files from your phase of the project to help imple- ment later phases of the project furniture and finishes or installation of equipment, for example.
With each exchange you must be aware of what is happen- ing and you must ask yourself some questions. Use in Facility Management. The owner may want to use the files to start a facility management system. In such situations, the owner may modify your files and go on to use them in ways you had never considered.
Caution Your CAD files can be changed without a trace by anyone who has copies of them. Protect yourself from liability for the problems of people who modify your files and then use them inappropriately. Include appropriate language in your agreements and in transmittals.
You must protect yourself from liability for problems arising from use of modified versions of your files. Make sure your contract language provides such protection. Also, keep careful documentation of your submittals both electronic files and hard copies so that in case a problem should arise, you will be able to determined just what was included in the files when you delivered them. Pre-project CAD data exchanges typically consist of files you receive from the owner or the general contractor that contain or are supposed to contain information you will need to do your work.
In working with such data exchanges, you must determine: S When will you receive the files? Exactly when are you supposed to receive the files? Who is responsible for providing them get the name of a specific person? If the files are not delivered when scheduled, will you get more time or money to complete your work? S Who made the files you will receive? S What do the files contain? Do they contain the information you need? S How were the files made? What was the CAD specification?
S What is the quality of the files? Are they complete? Are they correct? Will you have to field verify any of the information? What is the CAD specification for the files to be exchanged? How much effort will it take for you to make this translation? S Exchange Schedule. How many CAD files exchanges will you make?
How many are required in your con- tract? When will you make the exchanges? Remember that each exchange will take time and money. S Exchange Contents. What information will each exchange include? Which drawings will be included?
What will be shown on each drawing? What stage of completion does each exchange represent? How can you use the files you receive? S Documentation. How will you document these exchanges to track: what you deliver, what you receive, when exchanges are made, etc.? S Version Control. How will you know that you have the most current version of files from other team members? S Acceptance.
This issue arises in the case of progress submittals when the project team submits preliminary data to the project owner or perhaps construction manager.
In these situations, the party receiving the submit- A. On receiving this notification, the project team members can make required changes and proceed with their work.
How can you be sure review and acceptance will be timely? How can you protect yourself from being forced by deadline pressures to proceed with your work before receiving the necessary approval? See Liability on page A.
S Ownership. Who will own the electronic files that you deliver to others? In the case of coordination files ex- changed with other project team members, this is not a significant issue. It is an issue when design files are passed to the project owner or end user. See the discussion of this issue in the next section. In making such exchanges, determine. What is the CAD specification for the files you will submit?
S Submittal Contents. What specific information are you required to submit? At what point is the recipient deemed to have reviewed and accepted the files? When are you relieved of responsibility for the content of the electronic files? After all, electronic files deteriorate over time and they can be modified without a trace. At some point the recipient must assume responsibility for main- taining the files and safeguarding their contents. S File Ownership. Who will own the electronic files you deliver to others?
This becomes an important issue with the files that the project owner or end-user receives. Ownership will determine which party can use the information contained in the files and how the files can be used.
Depending on the specifics of your contract, you can retain ownership of your files, transfer ownership to the owner or end-user, or establish a shared own- ership of the files.
This may be the time to meet with the client or end-user to determine just how he plans to use your files and then discuss how you might work with the files and provide additional services. S The Receiver. Who will ultimately receive your submittal—the general contractor, the project owner, the end user, or consultant for a later phase of the work?
How will this party use your files? Is this an appropriate use for your files? If not, how can you protect yourself? S Archiving Issues. Does the project owner plan to keep your files as an archive? Does he understand the limita- tions of electronic archives? What should you keep for your own archive? A typical project team might include: designers and their design consul- tants, contractors and subcontractors, manufacturers and suppliers, and the project owner and end users.
Project team members work together in a complex matrix of relationships which changes as the project moves from preliminary phases through the end of construction and user occupancy. Project information flows through this matrix. At any time some project team members may want project information another member has or is developing.
At any time you may have information that another team member will want. Automation and CAD systems particularly have made it even easier to pass information back and forth among project team mem- bers and to do it quickly. The free, rapid flow of information among project team members can help team members communicate quickly, and can save time and effort as team members have the information they need instead of having to wait for it, and can keep the project moving forward.
The uncontrolled flow of project information among project team members can also pose risks. Without proper con- trol, team members can end up: S working with data that is incorrect, not ready, unchecked, or for other reasons should not have been exchanged S working with data that represents a design alternative rather than the actual design S working with design information that has not been approved for release S working with outdated information S working with multigenerational copies of data files S not knowing whether changes were made to the files as these copies were madeInformal information ex- changes among project team members can lead to these problems and raise serious liability problems.
In a well-run project, data exchanges between the team members are established in the contracts and are then managed carefully.
The manager may be the principal designer, the general contractor, the construction manager, or some other party. Without effective management of data exchange within the project team, each team member is on his own. Careful team members will implement their own data exchange management systems and there will be a great deal of dupli- cated effort. Whether project data exchanges are well managed or not, each project team member must protect himself. His goals should be: S to use CAD files received from others only if he can verify that they contain correct and current information S to assure that the information he is using from outside sources is kept current as changes occur S to assure that he releases only correct and current data to other team members S to document the whole process and develop a paper trail in case of later questions These principles apply when you are working on a multi-member project team.
They also apply when you are just working with other teams or even just other individuals in your own company.
When working on a multi-member project team, your first step is to determine the nature and structure of your contrac- tual relationships. This caution applies to other project team mem- bers, of course, but it also applies particularly to outsiders who want the information for their own uses. Let the general contractor or the project owner handle these requests.
If you are a sub-contractor to the general and you need to exchange CAD files with another sub, make the exchange through the general. Document everything that you receive and everything that you give to anyone else.
Documentation can help you re-construct events after the fact if questions arise. More immediately, though, documentation can help you and your project team to keep track of where things stand on a day-to-day basis. Let the general or designated data exchange manager manage these issues. Let the general keep track of who has received what, when the delivery occurred, percentage completion at the time of the exchange, etc.
Let the general act as the data coordinator and traffic cop for the project. Assume, then, that you have settled these contractual issues and are preparing to exchange CAD files with other mem- bers of the project team.
What files are included? Which drawings do they include? What were the design assumptions under which the drawings were made? What is the currency date of the material you are delivering? How complete are the drawings at the time of the exchange. S Be sure you deliver only what you intend to deliver. Check your files before you send them.
This simple precaution can save you embarrassment. S Document your delivery carefully. Keep a copy of your transmittal and other documents describing exactly what is being delivered. Keep hard copies of the drawings included in the CAD files. Keep copies of the CAD files. Keep a record of who is receiving the delivery and of your relationship with this party establish why you are making the delivery. List any third parties who you know will be receiving copies or your delivery.
S Update recipients. Whenever you receive CAD data files from another project team member: S Determine what you have received. Who made the files you have received—the sender, or another party? S Document it carefully. Keep any notes that you make during your confirmation of the delivery. Keep a copy of the files as you received them in your project records. S Commit to updating. Understand that you must keep yourself updated on any changes to the information.
This principle would be very helpful if each team member could work independently, never interacting with other team members, and just submit his finished work at the end of the project. Unfortunately, this is not the case, nor has it ever been the case except in the very smallest and least complex projects.
The success of any one team member depends on the other team members doing their jobs correctly: before he begins work, while he is working, and after his work is finished. They must pass a great deal of information CAD files and many other things back and forth during the project and they must be able to rely on the information they receive and stand behind the information they pass to others. This complicates the liability picture. Steps toward such a liability structure include: S project contracts that describe data exchanges between project members S who will provide information and who will receive it?
S how many exchanges will be made? S what will be included in each exchange? S what is the state of data currency at each exchange? S how can the data be used once it is received? S a structure to manage the day-to-day details of data exchange S tracking scheduled data exchanges S assuring that exchanges are made as scheduled S receiving CAD files from the parties who are supposed to provide them S verifying that the files contain the information they are supposed to contain S conveying the files to the parties scheduled to receive them S assuring that the parties who receive CAD files are kept current as changes are made to the files Establishing and operating this kind of structure requires a significant effort and additional costs—initially.
The effort pays off quickly in terms of improved data flow, reduced confusion, and clear liability. If this structure is established on a project-wide basis and if team members feel confident it will work smoothly, a sav- ings will be achieved by reducing duplicated efforts among team members as each tries to cover his own liability expo- sure. S A free and open exchange of information among the project team members. Such an exchange means that each party receives from other project team members the information he needs to perform his own work.
It also means that each party must provide information about his own work to other parties need for their work. S An equitable and appropriate distribution of liability among the members of the project team.
The most obvious benefits are using CAD in-house to produce your own drawings. Select a good CAD system and adopt an in-house project CAD standard similar to those used by your colleagues and you can experience significant gains in productivity as you produce your drawings, perform design calculations, generate quantity take-offs, etc. Using this infor- mation, you can: S get drawings of existing site conditions in CAD format rather than having to gather the information and draw it up yourself S learn about the design intentions of other team members S perform ongoing coordination between your work and that of other team members In achieving this second tier of benefits, though, you will encounter challenges in the areas of data coordination, addi- tional costs, and liability.
These challenges are best addressed by project-wide efforts that begin with the general contractor or the project owner. Lacking such efforts, you must take whatever steps you can to protect yourself and so must all the other team mem- bers.
The considerations above relate primarily to automating projects as they are currently performed. Creatively used, your CAD system can become a tool that will be useful in other ways, too. CAD work can be a way for you to make yourself known to the project owner. Using modern technological tools effec- tively to produce successful work can let you stand out on the project team and keep you from getting lost among all the other sub-contractors. Your CAD system can be a great sales tool.
CAD includes tools that will let you present your work to your clients in forms they can readily understand. A 3D model or a process flow simulation can help your client understand your de- sign with much greater clarity than you could achieve with 2D mechanical design drawings, performance charts, or verbal descriptions. Your sales efforts will be much more effective when you can communicate your proposal clearly, when you can really show it to your client. Your CAD system will let you offer new products and services that extend beyond the construction of the project.
As you use your CAD system to develop your project design, you build an electronic database that describes the facility and your design. If developed carefully, this database is a product that has great potential value to your client. You can add non-graphic data attaching to the graphic representation of a piece of equipment information such as: manufacturer name, model number, serial number, installation date, maintenance recommendations, etc.
Such a system can help a client manage system maintenance activities, assure inventory of belts and filters, or even issue preventive maintenance work orders. Like any other new and powerful tool, though, you must use it with planning and care.
S Does your computer hardware meet the requirement? S Is your computer hardware compatible with the requirement? For example, Microsoft Windows S Does it specify the name and version number of the operating system under which the files you deliver will be read? S Can your system work with this requirement? For example, AutoCAD S Do you have the required CAD software? S If not, will your CAD software let you deliver files that are compatible with the required format?
Think about this carefully. Make tests to verify this compatibility before you sign an agreement. S Other software S Does the CAD specification require you to use any other software such as design calculation software? S Can you meet this requirement?
Design Elements. How must your data directories and files be organized? S Drawing names and descriptions. What drawings are you required to produce? What must they be named?
What information must they include? S Reference file structure. What reference files must be attached to design files, and how must they be organized? Are there requirements for saved views that will include only portions of drawing files? These might specify several saved views of a drawing which each have different layers turned on or off.
They might also specify views that include specific portions of a larger drawing. How must the drawing information be divided into layers? What information goes into which layer? S Entity naming conventions. What names must you use for: assemblies, blocks, cells, details, symbols, etc.? S Line types, weights, and colors.
What line types, weights, and colors must you use? In what circumstances are you required to use them? S Text fonts and sizes. What line text fonts and sizes must you use?
S Symbols and other library materials. What library materials must you use? How are you required to use them? S Drafting Standards. What are drafting standards for the project? What are the established procedures for handling the project CAD work? S Number of and schedule for submittals. How many electronic file submittals are you required to make?
When must you make them? S Require submittal contents. What must be included in each submittal? S Procedure for each submittal. How must each submittal be made? Do procedures vary between submittals? S Review and acceptance procedures. How will your submittals be reviewed and accepted? Will they be re- viewed and approved in a timely manner? This would be impossible. Instead, the list aims to offer some specific guidelines, and also describe the questions you should ask through the life of a project.
Once you consider these questions and determine the answers, you can make decisions about the project. S Have you worked with this party before? S If so, was the previous project successful?
S If not, can you learn anything about the party? S Have other team members been identified? Who are they? S Who will receive the CAD files? Will all deliveries go to the same party, or will they be split? S How will these parties use the CAD files?
S Are these appropriate uses for the files? Can the files really be used in the way the recipient plans? S Is the party that requires the files CAD-knowledgeable? S Hardware and software requirements S Can you meet the requirements with your current system?
S Will you have to buy anything else? S Will you have to go through a learning curve with the new items? S What will it cost to implement these changes?
S Will you be required to translate CAD files to meet the spec? S Will you be able to test the file exchanges before you must make a submittal? S What will this effort cost and how long will it take? S What CAD materials will you receive from other project team members? S How will the material reach you? S Who produced the material? S Material content: does it contain the information you want? S Material organization: to what CAD specification was the material prepared?
S Material quality: does anyone certify that the material contains correct information? S Can you test samples of this material before you sign a contract? S What will it cost you to use this material?
S What CAD data must you submit? S What are the required submittals and when must they be made? Just paste the urls you'll find below and we'll download file for you! If you have any other trouble downloading smacna pdf post it in comments and our support team or a community member will help you!
Calculate Cs from the information in the applicable local building code 2. Calculate the values of Cs at the various attachment locations in the building 3. Terms zIt is not necessary for the contractor to fully understand the previous terms as these values should be determined by the designer.
General Requirements 1. Details provide lateral bracing system. Typical vertical supports per local building code must be used. Thermal expansion not given but must be considered. General Requirements 4. Brace in-line equipment independently of ducts and pipes. Cables to have minimum breaking strength. Per Table General Requirements 9. Expansion anchors per Table Proprietary connectors may be used where values are greater.
Welding to conform to AWS D1. Brace conduit same as equivalent weight of pipe. General Requirements Do not mix solid and cable bracing. Bracing for equipment NOT included. All runs will have a minimum of two transverse and one longitudinal braces. A run is defined as any change in direction except as allowed by offsets. Ducts are suspended from hangers 12 in. Hangers must be positively attached to the duct within 2 in.
Lateral motion will not cause damaging impact with other systems. Lateral motion will not cause loss of vertical support. Ducts have a cross-sectional area of 6 ft2 or less.
HVAC ducts are suspended from hangers 12 inches mm or less in length with hangers detailed to avoid significant bending of the hangers and their attachments, or » 2. HVAC ducts have a cross-sectional area of less than 6 square feet 0. Transverse and longitudinal bracing per tables Chapters 5, 6, 7 and 8.
Ducts may be grouped. Select bracing requirements based on combined weight.
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