Yeah, “addendum” is a fancy word, derived from Latin. The Latin background is the reason the plural is “addenda.” But really, what’s important is that it means something that’s added. In construction, it’s something added to or deleted from the contract, or something that revises the contract. Remember, the contract includes the contract documents – the drawings, the specifications, the agreements, etc.
The Project Resource Manual – CSI Manual of Practice, published by the Construction Specifications Institute, says that addenda are “written or graphic instruments issued to clarify, revise, add to, or delete information in the procurement documents or in previous addenda.” It goes on to say that “it is imperative that participants to the construction process properly account for these changes by posting or documenting the appropriate addenda information in the affected areas of the drawings and specifications.”
So, what is the proper procedure for design professionals when issuing addenda?
Remember that you are MODIFYING THE CONTRACT DOCUMENTS. The easiest way to think about this is to put yourself in the shoes of the people building the project. They are going to take your addendum, cut out the additions from the paper document of the addendum, and tape them over the things in the originally-issued documents that changed. They will strike through the things that your addendum deletes. When you, the design professional, issue addendum changes (or ANY modifications to the contract documents, actually) you NEED to actually MODIFY THE DOCUMENTS. If an Addendum item changes something about the contract documents, you have to actually modify the documents. You can’t just answer bidder questions without actually modifying your documents, the contract documents, to back up the answer to your question.
If you can’t put yourself in the shoes of the contractor, put yourself in your own future shoes. How does it feel when a question comes up late in the project, and you think that you may have changed something a while ago, but now you can’t remember what changed, and there is no official documentation of that modification? Feels bad. Looks bad to your client.
Do yourself, and your clients, and the contractor, a favor. Issue proper and complete addendum modifications. Change the actual documents, and, even if you don’t issue a whole drawing, document exactly what the change is, so that the intent is unambiguously communicated to all the participants in a construction project. You’ll probably thank yourself later!