How to Read a Floor Plan: Walls, Doors, Windows, Dimensions and Symbols

By Eli Gewirtzman, Owner · Last checked Nov 1, 2026

Start with the title, scale and north arrow, then trace the walls. Thick lines are walls, a gap with a quarter-circle arc is a door and the way it swings, and thin parallel lines inside a wall are a window. Read the dimension strings from the overall size inward, check each room’s label and size, and treat dashed lines as things overhead or hidden.

A floor plan is a view looking straight down at one level of a building, as if the walls were sliced through about four feet above the floor and the top lifted off. Everything the slice cuts (walls, door openings, windows) is drawn heavy. Everything below it (floors, counters, fixtures) is drawn lighter. Anything above it, like upper cabinets or a beam, shows up dashed. Each level gets its own plan, usually on sheets numbered A-101, A-102 and so on. Our guide to what sheet numbers like A-101 mean explains the numbering.

1. Find the title, scale and north arrow

The view title sits under the drawing, for example “FIRST FLOOR PLAN, SCALE: 1/4″ = 1′-0″”. At that scale, every quarter inch on the paper is one foot of house. The City of Burlingame, California, recommends 1/4 inch = 1 foot for most residential floor plans, and Hillsborough County, Florida, asks for no smaller than 1/8″ = 1′-0″. The north arrow shows orientation. Use the site plan or a known street bearing to identify the street-facing wall; sun exposure also depends on the site and season. If you plan to measure anything, read our guide on how to read an architect’s scale first.

2. Trace the walls

Walls are the heaviest lines on the sheet, drawn at their real thickness. A typical wood-framed interior wall is a little under 5 inches thick once drywall is on both sides, and exterior walls are usually thicker, so you can often tell them apart by eye.

On a renovation or addition, the plan has to tell old from new. Burlingame requires existing walls, proposed walls and walls to be removed to be “identified with distinctive hatch or marking.” A common office habit is existing walls outlined or lightly shaded, new walls solid or hatched, and walls to be demolished dashed, but offices differ. The legend on the sheet is the final word.

Bearing walls matter if anyone plans to move a wall later. Burlingame asks plans to say whether walls are load bearing, and Hillsborough County asks for the location of interior bearing walls and columns.

3. Read the doors and windows

The tag is where the real information lives. It points to the door and window schedules, which list each opening’s size, type and hardware. Hillsborough County requires a door and window schedule on new homes. You’ll also see door sizes written as four digits, like 3068. That’s common US shorthand for 3′-0″ wide by 6′-8″ tall. Window size codes vary more by manufacturer, so check the schedule rather than guessing.

Bedroom windows deserve a second look. Burlingame’s checklist notes that “minimum egress is required for sleeping rooms,” which may require an emergency escape and rescue opening, depending on the applicable code and exceptions. Size, clear opening, operation and sill height all matter; confirm compliance with the designer.

4. Read the dimensions

Dimensions are written in feet and inches, like 12′-6″. Outside the building you’ll usually find three or more strings stacked in rows:

1. Outermost string: the overall length of that side of the building.
2. Middle string: each jog, corner or bump-out.
3. Inner string: the location of each window and door, often to its centerline.

Add the parts of an inner string and they should equal the overall. If they don’t, ask the designer before anyone builds or orders materials. Inside, dimensions run between walls, and a general note says whether they go to the face of the stud, the face of the finish or the wall’s centerline. The difference depends on wall thickness and the chosen reference points; there is no fixed one-inch allowance. Read the dimensioning notes before calculating room sizes.

Written dimensions always beat a ruler. Measuring a print only works if it was printed at 100% at the size it was drawn at.

5. Read the room labels, fixtures and stairs

Each room has a label, often with its size underneath, like “BEDROOM 2, 12′-0″ x 11′-6″”. Labels aren’t decoration. Calaveras County, California, requires every room to be “clearly labeled by intended use,” because code rules for “egress, ventilation, lighting, smoke alarms, and fixtures are dependent on occupancy use.” Hillsborough County also asks for room dimensions and ceiling heights, so look for notes like “CLG 9′-0″” where a ceiling changes.

Inside the rooms:

• Kitchen: a solid line for the base counter, a dashed line for upper cabinets overhead, and boxes labeled REF (refrigerator), DW (dishwasher) and R (range). Our blueprint abbreviations guide decodes the rest.
• Baths and laundry: toilets, tubs, showers and sinks are drawn close to their real shape. W/D marks washer and dryer, WH the water heater.
• Closets: a line with a dashed line beside it usually means a shelf and rod, often noted “S&R”.
• Stairs: a run of parallel treads with an arrow marked UP or DN, as seen from the floor you’re on, and a diagonal break line where the cut plane slices through the stair. A note like “14R” gives the number of risers.
• Attic access: a small rectangle in a hall or closet ceiling. Hillsborough County lists a minimum of 22″ x 30″.

6. Check the dashed lines and the symbols

Dashed lines show things you can’t see from the cut: upper cabinets, beams, soffits, a roof overhang or a skylight above, or footings below. Circles with a line through them and arrows are section and elevation markers that send you to another sheet. How to read blueprints covers how those callouts work.

Smaller plans often put outlets, switches, lights and smoke and carbon monoxide alarms on the floor plan itself. Burlingame’s checklist asks for smoke detector type and locations, and outlets, switches and lights. Calaveras County requires electrical plans “on a separate sheet.” If your set has electrical sheets, our companion guide, how to read electrical blueprints, walks through them.

What permit reviewers look for on a floor plan

Three official checklists, side by side, show what a building department expects a residential floor plan to show:

Your town’s list may differ, so check its checklist before you submit. For how many paper copies a building department wants, see our plan copy requirements by state.

Printing a floor plan to scale

A floor plan only measures true if it’s printed at the size it was drawn at. Most house plans are drawn on 24×36 sheets. Our 24×36 (ARCH D) blueprint printing guide explains that size. A 1/4″ plan printed at half size becomes a 1/8″ plan, so use the written dimensions on half-size sets.

PrintMyPlans.com prints your PDF from your file, on 20 lb bond, at $1.95 per sheet in black and white or $3.75 in color. The price is the same at every size from 17×22 to 36×48. Printing only, before shipping:

WELCOME20 takes 20% off a first order, so the 24-sheet black-and-white example above comes to $37.44 in printing. Price your own set with the plan printing cost calculator. If you’re printing a full house set, see architectural plan printing. For builders’ field and permit sets, see construction plan printing.

We print plans; we don’t draw, check or change them. Questions about a wall, a dimension or a code item go to your designer.

FAQ

How do you read a floor plan for beginners?

Find the scale and north arrow, then trace the walls, doors and windows. Read the dimension strings from the outside in, check each room’s label, and use the legend for any symbol you don’t know.

What do the dashed lines on a floor plan mean?

Usually something above the cut, like upper cabinets, beams or a roof overhang, or something hidden below. On renovation plans, dashed walls often mean walls to be removed. The legend confirms it.

How do I read door sizes like 3068 on a floor plan?

The first two digits are the width and the last two are the height, in feet and inches. 3068 is 3′-0″ wide by 6′-8″ tall. The door schedule gives the full details.

Which dimension is first in a room size, like 12′ x 14′?

It varies by office. Many list the left-to-right width first, but check against the dimension strings on the plan before ordering flooring or furniture.

Can I measure a printed floor plan with a ruler?

Only if it was printed at 100% at its drawn size, and even then the written dimensions win. Check one known dimension first. If it’s off, the print was scaled.

Printing it

When the PDF is final, upload it on the order page, choose the size it was drawn at, black and white or color, and the number of copies. Order by 3 PM ET, ships same day, to all 50 states. If we make a mistake, we reprint and ship it free of charge.

Sources

• City of Burlingame, CA, Building Division, Residential Floor Plan Checklist (Dec 2025)
• Calaveras County, CA, Building Department, Single Family Residence Plan Submittal Guidelines
• Hillsborough County, FL, Residential New Construction, Floor Plan Requirements (last modified May 20, 2025)

Order by 3 PM ET, ships same day. Delivery timing depends on the shipping service and destination. See the terms for business-day and holiday details.