What do all these types of lines in architecture plans mean?

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What Different Line Types in Architecture & Design Drawings Mean

Thick lines, thin lines, lines with brusque or long dashes (or both!) — if you don't speak the language of all these line types, an architecture or design drawing tin can be pretty mystifying. This primer on design drawing linework will give you a starter toolkit so you can tell what you're looking at.

July sixteen, 2020

Dashed lines, solid lines, ones with dashes and dots, thick ones, thin ones… What do all these lines mean?

Have you ever heard someone talk in a jumble of letters and have no idea what the heck they hateful? Well, we hate using acronyms, equally they do a lot to make other people feel, well, non so smart. No 1 likes feeling like they accept no idea what is going on. In the same respect, reading an architectural drawing is something that can be incredibly confusing to people who don't know what the heck they're looking at. Just like speaking in acronyms can sow confusion, we've establish that when we show an architectural drawing to a client, they often don't know what they're reading, and conveying a design concept tin can exist muddled by the fact that they just don't quite know what they're looking at.

So, in the interest of helping people understand what an architecture, interior pattern, or mural compages drawing is communicating, here's a quick primer on what those pesky lines signify. We'll note, though, that there are going to be exceptions to the rules here, and non all architects are the same. But most architects and designers are generally post-obit these rules. We'll also add, that if y'all don't understand what something is you should admittedly feel OK request, "What does this line mean?"

Solid Versus Dashed or Dotted Lines

The first and nearly basic rule of lines in blueprint drawings is that solid lines indicate visible or "real" objects or surfaces, while anything drawing with dots and/or dashes indicates something that is unseen or "hidden" from view. Lines can represent dissimilar things depending on what "view" you are looking at — for instance, are yous looking at the confront of one wall of your room and you meet lines that stand for a window? That's an "elevation" view. Or are yous looking at the flooring and you lot tin run across lines that represent all four walls of your room? That's a "program" view. In both cases, the solid lines signal the boundaries of what you lot are looking at.

Solid Single Line

In a programme view, a solid single line is commonly something like the edge of a cabinet, a floor threshold, the nosing of a stair, or the edge of a tabletop. Information technology isn't a wall (read more about what walls await like beneath). In an pinnacle view, a solid line is something that has an edge or a corner, like a cabinet or a window frame or door jamb.

Solid, Single Lines – Types of lines or linetypes in architectural drawings.
Solid, Unmarried Lines Viewed in a Floor Program

Usually, this type of line is indicating something that is an edge, such as the edge of a stair or the edge of a countertop.

Solid Single Lines in Elevation – Types of lines or linetypes in architectural drawings.
Solid, Unmarried Lines in Summit Views

Like in a plan view, solid lines normally indicate things that are edges, like the edge of a window or the edge of a cabinet.

Two Solid Lines with a Hatch or Shaded Fill

This is a wall, and it but shows upwardly like this in plan views. The hatch or shaded fill within the wall varies per architect or designer, and in that location should e'er be a legend that explains what that hatch or shade represents. Typically, nosotros will show an existing wall with a low-cal greyness shaded make full in between the lines, and show new walls with a night gray shaded fill in between the lines.

Solid, Paired Lines – Types of lines or linetypes in architectural drawings.
Pairs of Solid Lines with a Shaded Fill in a Floor Plan

These pairs of lines betoken walls. If there are just two lines, they point the surface of the wall cease on each side of the wall. If there are other, thinner lines inside the hatch or shaded expanse, these can bespeak some of interior components that brand up the wall.

A Short-Dashed Line

In a plan view, we denote a short-dashed line as something that is higher up what you can see in the rest of the drawing. A flooring plan is actually a representation of a house if someone basically sliced the top of your building off at 4 feet above the flooring, then drew what they saw remaining. When that happens, in that location are things — like upper cabinets, or large, trimmed out openings above a pass-through between rooms — which you tin't see when the elevation half of your building is cut off. To convey these things, as they're important to know that they're there, they are shown with a short-dashed line.

Short-Dashed Lines – Types of lines or linetypes in architectural drawings.
Curt-Dashed Lines Viewed in a Flooring Plan

Lines fabricated of short dashes in a plan view indicate things that are overhead, or rather, over the height at which the plan was "cutting" — usually things above about 4' from the floor.

Short-Dashed Lines in Elevation – Types of lines or linetypes in architectural drawings.
Short-Dashed Lines in an Acme View

In an top view, these short dashed lines are unremarkably indicating something you tin't see. In the plan view, you couldn't see them because they were above the view plane. In an elevation view, you can't see the things because they are backside doors, or otherwise hidden from view.

A Long-Dashed Line

A different type of dashed line (and it isn't always consistent between blueprint firms) tin show things that are slightly different than a short-dashed line. In a plan view, a line with long dashes is often something that is much higher above you than something that would be shown with a brusque-dashed line, like the eaves of a roof. These can be helpful for reference and are chosen out in a different line type than their shorter-dashed sibling.

In an acme view, long and brusque-dashed lines are unremarkably depicting different elements that are all hidden from view, like shelves behind a cabinet door and a microwave sitting on that shelf. But they can also be used to delineate spaces that are "open" and not to be confused with a solid wall.

Long-dashed Lines – Types of lines or linetypes in architectural drawings.
Long-Dashed Lines in a Floor Plan

Lines equanimous of longer dashes as well show things that are in a higher place the view, but are used to prove things that are much higher, like the eave of a roof overhead.

An Alternating Long and Short Dashed Line

This alternating long and short dashed line has a name, a centerline. This line is non "existent" per se, it indicates the exact middle of whatever it is passing through for purposes of alignment and spacing.

For example, you might come across a centerline passing through a doorway or a toilet to indicate the location of these objects in the context of their environs. Sometimes (as with a toilet shown in a program cartoon) it has round edges, and the symbol for it in the drawing is a stand up-in for the actual toilet. If its location is designated past the centerline of it, rather than a side edge, these small variations are accounted for.

Centerlines – Types of lines or linetypes in architectural drawings.
A Line with Alternating Short and Long Dashes

These are centerlines, and they can show up either in programme or superlative views. They marking the centers of objects for the sake of locating them for construction.

In other cases, similar the doorway, it could be that the most important matter well-nigh the location of the doorway is that information technology is centered in the room. Indicating how far the door jamb is from the corner of the room might non end upwardly with the desired results, specially if the width of the opening changes during construction, whereas indicating its centerline is oriented in the room volition.

This line tin also be accompanied by the CL symbol, which is a helpful reminder of "Heart Line" written in a fancy shorthand.

A Single, Curved Line Forming Role of a Circle

This is easily the one that I most oftentimes forget to explain to clients and a lot of people (you're not alone!) have no idea what this means! It is commonly drawn as a solid line (although some architects draw information technology as a dashed line) and conveys where the door will swing. This is shown to help convey how the door swings to the contractor and to ensure that the door, every bit information technology swings, won't smack into something.

Door Swings – Types of lines or linetypes in architectural drawings.
Arced Lines in a Flooring Program

These arcs are attached to the end of rectangles that represent doors. The arcs are tracing the swing of the door as information technology opens, from the edge of the door to the jamb.

Thicker vs. Thinner Lines

Is the line thin or thick or somewhere in between? Dorsum in the proverbial day, when drawings were done by manus, the thickness of your lines helped convey the importance and hierarchy of what was depicted in the drawing. As we accept moved into 2D and at present 3D drawings, the weight of a line nonetheless conveys bureaucracy. Typically, a thick line is either something closer to you (similar in an elevation or building department), or is something more than chief, like the edge of a wall in a program. A thin line is either something farther away or something less of import. This helps your encephalon understand and translate what you're seeing.

Sometimes, clients already know what they're looking at, simply — we figure — improve prophylactic than sorry. Besides, like we said, non all design teams follow these rules exactly, so what yous might have understood in years past working with another designer might not always translate perfectly. When in dubiousness, just ask. We always capeesh it when clients inquire us questions!