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

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What Different Line Types in Architecture & Blueprint Drawings Mean

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

July 16, 2020

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

Have you e'er heard someone talk in a jumble of letters and have no idea what the heck they mean? Well, nosotros detest using acronyms, every bit they exercise a lot to brand other people feel, well, non so smart. No one likes feeling like they have 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. Merely like speaking in acronyms tin sow confusion, nosotros've found that when we show an architectural cartoon to a client, they often don't know what they're reading, and conveying a blueprint concept can exist muddled by the fact that they just don't quite know what they're looking at.

Then, in the involvement of helping people understand what an architecture, interior design, or landscape architecture drawing is communicating, here'due south a quick primer on what those pesky lines signify. We'll notation, though, that in that location are going to be exceptions to the rules here, and not all architects are the same. But most architects and designers are generally following these rules. We'll also add, that if you don't understand what something is you should absolutely feel OK asking, "What does this line mean?"

Solid Versus Dashed or Dotted Lines

The outset and virtually basic rule of lines in design drawings is that solid lines signal visible or "real" objects or surfaces, while anything cartoon with dots and/or dashes indicates something that is unseen or "hidden" from view. Lines can correspond unlike things depending on what "view" you are looking at — for example, are you lot looking at the face of one wall of your room and yous see lines that represent a window? That's an "height" view. Or are you lot looking at the floor and you lot can see lines that stand for all four walls of your room? That's a "plan" view. In both cases, the solid lines point the boundaries of what you are looking at.

Solid Single Line

In a plan view, a solid unmarried line is ordinarily something like the border of a chiffonier, a floor threshold, the nosing of a stair, or the edge of a tabletop. It isn't a wall (read more than near what walls await like below). 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, Single Lines Viewed in a Floor Plan

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

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

Like in a program view, solid lines usually signal things that are edges, like the border of a window or the edge of a cabinet.

2 Solid Lines with a Hatch or Shaded Fill

This is a wall, and it simply shows up like this in plan views. The hatch or shaded fill inside the wall varies per architect or designer, and there should ever exist a legend that explains what that hatch or shade represents. Typically, we will show an existing wall with a light gray shaded fill in between the lines, and prove new walls with a dark grayness 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 Flooring Program

These pairs of lines betoken walls. If there are but two lines, they indicate the surface of the wall finish on each side of the wall. If there are other, thinner lines inside the hatch or shaded expanse, these tin can point some of interior components that make upward the wall.

A Short-Dashed Line

In a plan view, nosotros denote a short-dashed line as something that is above what you can run into in the rest of the cartoon. A floor programme is actually a representation of a house if someone basically sliced the top of your building off at 4 feet above the flooring, and so drew what they saw remaining. When that happens, there are things — like upper cabinets, or big, trimmed out openings higher up a pass-through between rooms — which you lot tin't see when the top one-half of your building is cutting off. To convey these things, every bit they're important to know that they're at that place, they are shown with a brusk-dashed line.

Short-Dashed Lines – Types of lines or linetypes in architectural drawings.
Short-Dashed Lines Viewed in a Floor Programme

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

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

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

A Long-Dashed Line

A unlike blazon of dashed line (and information technology isn't ever consistent betwixt blueprint firms) can 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 college above you than something that would be shown with a brusk-dashed line, like the eaves of a roof. These can be helpful for reference and are called out in a different line type than their shorter-dashed sibling.

In an tiptop view, long and short-dashed lines are usually depicting different elements that are all hidden from view, like shelves backside 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 exist 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 too show things that are above 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 brusk dashed line has a proper noun, a centerline. This line is non "real" per se, it indicates the verbal heart of any it is passing through for purposes of alignment and spacing.

For example, you lot might see a centerline passing through a doorway or a toilet to signal the location of these objects in the context of their environs. Sometimes (every bit with a toilet shown in a plan drawing) it has circular edges, and the symbol for it in the cartoon is a stand up-in for the actual toilet. If its location is designated by 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 Alternate Short and Long Dashes

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

In other cases, like the doorway, it could be that the nearly important matter most the location of the doorway is that it is centered in the room. Indicating how far the door jamb is from the corner of the room might not end upwardly with the desired results, especially if the width of the opening changes during structure, whereas indicating its centerline is oriented in the room will.

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

A Single, Curved Line Forming Office of a Circumvolve

This is easily the one that I most often forget to explain to clients and a lot of people (yous're not alone!) accept no idea what this ways! It is usually drawn as a solid line (although some architects draw it equally 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 it swings, won't smack into something.

Door Swings – Types of lines or linetypes in architectural drawings.
Arced Lines in a Floor Plan

These arcs are attached to the cease of rectangles that represent doors. The arcs are tracing the swing of the door every bit it opens, from the border of the door to the jamb.

Thicker vs. Thinner Lines

Is the line thin or thick or somewhere in betwixt? Back in the proverbial twenty-four hours, when drawings were done past hand, the thickness of your lines helped convey the importance and hierarchy of what was depicted in the drawing. Every bit we take moved into second and now 3D drawings, the weight of a line still conveys hierarchy. Typically, a thick line is either something closer to yous (like in an meridian or building section), or is something more primary, like the edge of a wall in a plan. A thin line is either something farther away or something less important. This helps your encephalon understand and translate what yous're seeing.

Sometimes, clients already know what they're looking at, but — nosotros effigy — better safe than sorry. Besides, similar we said, not all design teams follow these rules exactly, so what you lot might have understood in years by working with another designer might not always translate perfectly. When in uncertainty, just inquire. We ever capeesh it when clients ask usa questions!