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Al Whitley/4 min read

Understanding Site Plan Scales and Property Boundaries in Architectural Drawings

Site Plan Reading

Site Plan Scale

Typically 1:50 or 1:100 metric; 1″ = 20'/40' imperial.

Property Boundary

Heavy line with bearings and distances marked.

Setbacks

Dashed lines indicating required distances from property lines.

Easements

Areas where utilities or access rights are reserved.

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This tutorial walks through understanding site plan scales and property boundaries in architectural drawings, covering essential tools and techniques for your projects.

Now what I'd like to show you is the site plan. So here we have the site plan for the house. Here is the house, right here in the middle of the property.

You can see that it says site plan. Over here on the right, it says 1 inch equals 100 feet. So like I showed you in the scaling drawing, all of this stuff was drawn real size, but it was scaled down to fit on our cover sheet at a scale of 1 inch equals 100 feet.

Now we typically have two different kinds of scales that we will use when we're measuring drawings. We have architectural scales and we have engineering scales. And there's also metric scales, but in North America, we don't do a lot of metric construction.

An architectural scale is more commonly used on the house itself. A quarter inch equals a foot, a half an inch equals a foot, an inch equals a foot. Engineering scales are typically broken down into tenths of an inch.

So on an engineering scale, 1 inch represents 100 feet, and what that would mean is if you were to have the appropriate scale in your hands, and if you were to have the drawing printed on paper, that if you were to measure, for example, this segment here, this is saying that from this point right here to this point right here is 290 feet. Now again, the full size of this set of drawings are 22 × 34 inches. The images that you are printing off are half size, which would be 11 × 17.

So you would have to print this area at full size in order for the scale to work. But if you were to print this area at full size, and if you were to hold down your scale that was a 1 inch equals 100 foot scale, that when you measure from this corner to this corner, it would actually measure as 2.9 inches because 2.9 inches reflects 290 feet. Now you can see this line that goes around the periphery of the project.

This is called the property line. The line type is called a property line type. In CAD, we will frequently use a phantom line type to represent the property line.

The property line is typically represented by a long dash, two shorter dashes, and the pattern repeats. Now you can see that again this is saying from this corner to this corner is 290 feet. But above it are what we call Meets and Bounds information.

This is saying that measured from this corner right here that this segment of the property is 290 feet long, but its angle is north 89 degrees 51 minutes 36 seconds west because we have four directions. I'm going to go down here to the north arrow. We have north, we have south, we have east, and we have west.

When we do Meets and Bounds information, we typically present the information using Northings. And what that means is the direction of a property line relative to north and south, but then as it swings towards east or west. So I can see that this segment right here is 290 feet long.

It's going north 89 degrees 51 minutes 30 seconds towards west. This segment right here is going north, and it's going 350 feet. This longer segment here is going south 590 feet, but it's going south 33 degrees so many minutes and seconds towards east.

So again you have the Property Lines which are normally conveyed using the Meets and Bounds information. If I look at this segment over here on the left that's saying 350 feet, so it's saying north 350 feet, you can see the property line, but you can also see these little arcs that are right here, and those arcs are telling us the length of the segment that is being presented as north 350 feet. We have the Property Lines, we have the Meets and Bounds information.

Inside of that you see a dashed line. That dashed line represents the property setback. We typically have regulations that tell us how close we can build to the edge of a property, and so we have setbacks that are saying you cannot build within this area.

We have the property line, inbound of that we have our Setback Line. I have a description of the property, so you can see I have the Assessor's Parcel Number, and then you're seeing that it's showing that this property is 10 acres.