If you’re an architect, need I say any more?
If you’re not an architect, I’m going to explain. A red line is not referring to the elevated train (“L”) in Chicago that runs north and south through the Loop, nor is it a great BMX bike and it is not referring to the process where mortgages are denied for various reasons (racist and discriminatory reasons). The phrase “red lines” or “red-lining” is an architectural idiom or might I say slang term for the process where architects make editorial notes on a set of drawings, generally construction drawings, with the understanding that a lesser experienced staff member will make those revisions to the actual drawings. To some it’s the bane of their existence and something most interns can look forward to upon graduation. A highlighter is used to cross out or highlight the markings in order to know they’ve been addressed. In my world, being a one-person office, I must “pick up” my own red lines. I have to admit, there are many times I’d love to make them and walk away knowing someone else will handle them.
Part of my lack of regular writing lately is I’m in the midst of developing a set of construction drawings for a project and since I share how architects think about what we do, this seemed like an obvious topic. For me to truly see the drawings clearly and think about the content, I must print out copies of them (usually at a smaller scale) and as I’m thinking through issues, I draw on them with a red pen. I often have a draft set handy with a series of running comments to remind me of items needing to be addressed, oftentimes with the assistance of others.
Why do we use a red pen? I suppose it’s just tradition and we don’t question tradition. Actually it’s really very practical. It’s the easiest color to see and recognize that it’s not part of the final drawing.
Years ago (yes a story is coming), and I don’t mean centuries ago, just earlier in my career, architects made drawings by hand on vellum or sometimes mylar. The drawings were copied with a developer type machine and the resulting copy had a white background with blue lines (some referred to as blue prints, although technically incorrect and archaic). Oftentimes the exposure was set a bit dark and there was a lot of bluish background to the drawing. Using a red pen was simply the easiest color to see. For those of you who are focused on being PC or just a bit sensitive, red pens are not intended to be mean or pejorative. Red is not seen as a critical color, just an easy one to see. Now I haven’t always had that opinion. I started out my career frequently “picking up” red lines where my boss would review a set of drawings and make his notes with a red pen. Once he was through with his notes, he would give me the set and I would make the changes on the original drawings. I had a mix of emotions each time, many unpleasant. The worst was when he would add one word in the middle of a large paragraph. Drawing by hand and using pencil, we had to erase part of the paragraph and insert the word and re-letter the remaining words. Years later I shared that story with him and he laughed. I wasn’t laughing at the time, especially when adding one word made me feel the boss was being a bit petulant.
I still think on paper. I constantly sketch, doodle, make notes and think out loud on paper with yes, a red pen. These red-marked drawings are an important step in the architectural process. Many decisions and thoughts are contained in them. It’s where we really imagine how the building parts come together and we make important notes and reminders of elements to coordinate. No one just sits down and draws a drawing. I’m sure there are many that can think and edit on the screen. For me to “see” the drawings for both content and line quality, I must print draft copies and scribble all over them. I used to get frustrated at my first job when the boss would “bleed” all over the drawings. It’s easy to take it personally like you’ve done something wrong or didn’t live up to the standard. Now I look back and see that architecture is hard and there are many things to think about and coordinate. Sometimes a fresh eye looking at the drawings (not on the screen) sees what is missing. Fortunately, there is a sense of completion that the important issues are incorporated when you look at a set of red lined drawings and the red lines have been highlighted.
This is just something architects do.
think | architect 
Lee- Hold on to your redlines until the job is done-done and you’ve been paid. You may need backup at some point to justify your work and fee. Folks often relate to quantity as opposed to quality and equate volume to payment. I’m loving your “think l architect”.
Larry, great to hear from you and thanks for reading. You’ve got over a year and 105 more posts to catch up. Yes I usually keep most work products in the file. I keep my sketches especially. I like to know where the root of ideas came from and my earliest thoughts.
Lee, I have fixed many red lines in my career and drawn them for others to fix. I remember one time that I put a detailed note on the drawings in red for the draftsman to make a change to a particular detail. Instead of making the change to the detail he actually wrote out the note with an arrow to the detail. That one sure tried my patience.
I’ve had the same thing happen many times too. I started using different color pens to distinguish between notes to the person and notes to make on the drawing. That got cumbersome.
Been there done that…red make change…blue for ‘changer’ to read/consider.
I did the same thing, but probably lost track of which pen meant what…
Lee i think your memory has been corrupted. Blue Prints were BLUE Background with WHITE Lines.
How did I miss your comment from five years ago? I appreciate the comment, but in my post, I linked to another post where I explained the history of “blueprints.” You are correct, but I was using the term in a newer context. The fact that people still use this word – even in a generic sense (i.e. the blueprint of the political plan to…), drives me nuts. Everyone uses this term – except architects. The world is a strange place. Thanks, five years later, for reading.
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Yeah redlining in the sense of the mortgage comment…it was not denial for “various reasons” it was for racism and discrimination.
You’re correct. I edited the post to note that. As architects, we use the term due to the color of the pen. The other process is unrelated to this post, but is awful, abhorrent, and altogether wrong.