How to Read Architectural Drawings: A Seattle Homeowner’s Guide”

TL;DR: Architectural drawings fall into five types, site plan, floor plan, section, elevation, and detail. Understanding the scale bar, title block, and cut-line notation on each sheet lets you follow your project without guessing. At Piper Cole Architects, we walk every client through a design narrative session before construction documents are issued so nothing gets lost in translation.

Every week I sit across a table from a Kirkland or Bellevue homeowner who holds a set of drawings, nods along during our review, and then admits they aren’t sure what half the lines mean. That is completely normal. Architectural drawings are a professional communication tool built for contractors and building officials, not for the people who will actually live in the finished house. My job is to make sure you can read them anyway, because an informed client catches problems before concrete gets poured.

Here is what I teach every homeowner who works with Piper Cole Architects on a residential project.

The Five Drawing Types You Will See on Any Seattle Project

Every set of construction documents contains five core drawing types. They work as a system, you cannot fully understand one without referencing the others.

1. Site Plan

The site plan shows your property from above, drawn at a small scale (typically 1″=20′ or 1″=30′). It locates the building footprint, setbacks from property lines, driveway, utility connections, and site drainage. In Seattle and Kirkland, the site plan is the sheet the permit reviewer looks at first to check zoning compliance, front yard setbacks, lot coverage percentage, and impervious surface limits all live here.

2. Floor Plan

The floor plan is a horizontal cut through the building, typically drawn 4 feet above the finished floor. Think of it as a slice, everything below the cut shows as solid walls (usually hatched or filled), and everything above shows as dashed lines. Floor plans are typically drawn at 1/4″=1′-0″ for residential work.

3. Building Section

A section is a vertical cut through the building, like slicing a loaf of bread. It shows floor-to-floor heights, ceiling heights, structural members, insulation layers, and how the roof connects to the walls. Cut lines on the floor plan (a dashed line with arrows and a sheet reference number) tell you exactly where the slice was taken.

4. Exterior Elevation

Elevations show each face of the building as a flat projection, north, south, east, and west. They call out materials, window and door heights measured from finished floor, roof pitches, and how grades (the ground level) relate to the building. If you want to understand what your addition will look like from the street, the elevation is your sheet.

5. Detail Drawing

Details are large-scale drawings, often 1.5″=1′-0″ or 3″=1′-0″ that zoom into a specific condition: how the window flashing meets the siding, how a beam bears on a post, how the deck ledger attaches to the house. These are the sheets that prevent water intrusion in Seattle’s climate.

How to Read a Floor Plan: The Five Things to Check First

When you open a floor plan, work through these five elements before reading any other information:

Scale bar. Every drawing sheet has a scale bar printed directly on it. Use it even if the drawing says “1/4″=1′-0” in the title block, sheets sometimes get photocopied at reduced size, and the scale bar remains accurate even when the stated scale does not.

North arrow. Solar orientation matters enormously for passive solar design and window sizing. The north arrow tells you which direction is which. On a Seattle hillside lot, the north arrow also helps you locate the view.

Room labels and areas. Each room is labeled with its name and, on well-prepared drawings, its square footage. Washington State requires bedroom dimensions to meet minimum egress window requirements, checking the bedroom dimensions on your floor plan is something you can do yourself.

Door swings. Doors are shown as a thin arc indicating which way they swing open. A door that swings into a tight bathroom or blocks a light switch is easy to catch on paper and expensive to fix in framing.

Window tags. Windows are referenced by a letter-number tag (e.g., “W-3”) that corresponds to a window schedule elsewhere in the drawing set. The schedule tells you the unit size, manufacturer, glazing type, and U-factor, important for Washington State energy code compliance.

Reading a Building Section: Heights and Structure

When I show clients a building section during a schematic design review, I point to three numbers first: the floor-to-floor height, the floor-to-ceiling height (which is shorter because the structural floor assembly eats some space), and the overall building height from grade. In Kirkland, residential height limits are typically 30 feet measured from average finished grade, a number that comes directly from the section drawing.

The section also shows where insulation layers go. On a passive house project, I will dimension the wall thickness (often 12 to 16 inches) and label each layer: interior drywall, service cavity, continuous insulation, structural sheathing, drainage plane, siding. Clients who understand sections can verify that what they approved in schematic design made it into the construction documents.

Reading Exterior Elevations: Materials and Water

Elevations call out materials using a combination of graphic hatching and text notes. In the Pacific Northwest, I spend significant time on elevations showing how siding changes occur at inside corners and how window trim relationships are maintained across a mixed-material facade. The elevation also shows the finish grade line, drawn as a solid line at the base of the building, versus the rough or existing grade, shown as a dashed line. The vertical distance between the two tells you how much fill or cut is involved in grading the site.

The Title Block: What Every Sheet Tells You

Every drawing sheet has a title block, usually at the right edge or bottom right corner. It contains: the project name and address, the sheet title (e.g., “A2.1, First Floor Plan”), the drawn-by and checked-by initials, the issue date, and the revision history. The revision cloud, a series of connected arcs drawn around changed areas, lets you find exactly what changed between one drawing version and the next without reading every line.

The architect’s stamp and signature appear on the cover sheet of permitted drawings. In Washington State, only a licensed architect (or licensed engineer for structural-only scope) can stamp drawings for permit submission. That stamp is your assurance that a licensed professional has taken responsibility for the design.

How We Present Drawings at Piper Cole Architects

I never hand a client a rolled set of drawings and expect them to figure it out alone. At every design milestone, schematic design, design development, and construction documents, we conduct a design narrative session where I walk through each sheet, explain the intent, and answer questions before the client signs off.

We also prepare 3D views alongside the 2D drawings for every project. A rendered perspective of the living room addition or the new kitchen shows the space in a way a floor plan simply cannot. The 3D view and the floor plan reference each other: once you can find yourself standing in a 3D view and locate that same point on the floor plan, the drawings start to read naturally.

For clients who want to go deeper, I recommend our first consultation guide before our initial meeting, it covers the questions to ask and the documents to bring.

Common Questions Homeowners Ask When Reading Drawings

“Why does the wall look thicker on some sheets than others?” Scale. At 1/4″=1′-0″ a 6-inch wall is a very thin line. At 3/4″=1′-0″ that same wall is drawn proportionally thicker and includes the individual layers. Both are correct.

“Why are some lines dashed?” Dashed lines show elements above the cut plane (like a ceiling soffit or an upper-level overhang), elements hidden below the floor (like a beam or foundation wall), or proposed demolition.

“What does NTS mean?” Not to scale. Diagrams, like a detail that is drawn schematically to show a concept rather than exact dimensions, are sometimes marked NTS. Never measure off an NTS drawing.

Ready to review drawings for your Seattle-area project? Contact Piper Cole Architects and let us walk you through the process from the first sketch to the stamped permit set. We serve homeowners across Kirkland, Bellevue, Redmond, and the Seattle Eastside.

Frequently Asked Questions

Work With Piper Cole Architects

Whether you are planning a first addition, a whole-house remodel, or a new custom home on the Eastside, we bring clarity to every set of drawings. David Meade, AIA, NCARB has guided hundreds of Seattle-area homeowners through the design and permitting process, and we will make sure you understand every line on every sheet before a contractor breaks ground.

Contact Piper Cole Architects

425-753-6452 | Kirkland, WA | Serving the Seattle Eastside

Sources

1. American Institute of Architects. Architectural Graphic Standards, 12th Edition. Wiley, 2016.
2. Washington State Department of Labor & Industries. Architectural Licensing Requirements, RCW 18.08. lni.wa.gov.
3. City of Kirkland Development Services. Residential Permit Submittal Requirements. kirklandwa.gov.
4. Passive House Institute US (PHIUS). Drawing Set Requirements for PHIUS+ Certification. phius.org.