Floor plan symbols
Every mark you will meet on a house plan, drawn, with what it means: the line types, walls, doors and windows, stairs and levels, plumbing fixtures, furniture, electrical symbols, and the grid lines, section marks and tags that tie one sheet to the next.
Symbols drawn in detail
Three symbols cause most of the questions, so each has its own page: the symbol drawn in a room, its variations, and what to check on your own plan.
- Stairs on a floor planThe UP arrow, the break line, the stair on each floor, stair shapes and counting risers.
- Sliding door on a floor planFixed and sliding panels, O and X, pocket and barn doors, and the opening each leaves.
- Window symbol on a floor planWhy the symbol looks that way, each window type in plan and elevation, and the schedule.
How a floor plan is drawn
A floor plan is the house seen from above, cut part of the way up the walls, above the window sills. Anything the cut passes through, such as a wall, is drawn with a heavy line. Anything below the cut, such as a counter or a bed, is drawn lighter. Anything above it, such as the roof eave, a beam or upper cabinets, is drawn dashed. That one rule explains most of what is on the sheet.
A floor plan is drawn to scale. At 1:100, one centimetre on the paper is one metre of the house. The rules under the National Building Code ask for floor plans at 1:100 or larger. Dimensions are usually in millimetres, and the sheet says so in its title block.
Lines
Every plan uses a small set of line types, and the type tells you what the line is before you read any label.
- Object line A heavy continuous line: something cut through or in plain view, such as a wall.
- Hidden or overhead line Dashed: something above the cut or out of sight, such as the roof eave, a beam or upper cabinets.
- Centre line Long and short dashes: the centre of a column, a wall or an opening.
- Property line A long dash and two short ones: the lot boundary on a site plan.
- Break line A zigzag: the drawing stops here, though the thing drawn carries on.
- Leader A thin line with an arrow or dot, pointing from a note to the thing it describes.
Walls and doors
Walls are the heaviest lines on the sheet. A door is drawn open, so you can see which way it swings.
- Exterior wall Two lines with hatching or a solid fill between them. Thick, because it is usually CHB or concrete.
- Interior partition Two thinner lines closer together: a lighter wall between rooms.
- Single swing door The arc is the path the leaf sweeps. The hinge is where the leaf meets the wall.
- Double door Two leaves meeting in the middle, each with its own arc.
- Sliding door Two panels side by side within the wall, overlapping where they pass.
- Folding door A zigzag of leaves that fold against each other as the door opens.
- Pocket door A leaf drawn dashed inside a hollow wall, where it slides out of sight.
- Opening with no door A gap in the wall with its sides drawn: a doorway or a cased opening.
Windows
A window is drawn as thin lines set into the wall. The window schedule, keyed by the window mark, gives its size and type.
- Window Thin parallel lines within the thickness of the wall.
- Sliding window Two sashes drawn side by side and offset, like a sliding door.
- Awning or casement window A sash drawn opening out from the wall, sometimes with a short arc like a door.
- Jalousie or louvre window Short slanted lines across the opening for the glass or aluminium blades.
Stairs, levels and slopes
Plans are flat, so changes of height are shown with arrows and level marks.
- Stair Treads drawn across the flight, an arrow from the lower floor marked UP, and a break line where the plan cuts it.
- Level mark A height above a reference point, such as the finished floor or the road crown.
- Ramp An outline with an arrow pointing down the slope. The slope itself is written beside it.
- Step in the floor A single line across the floor where the level changes, with a level mark on each side.
Plumbing fixtures
Fixtures are drawn roughly to their real size, so the plan shows whether they fit the room.
- Water closet (toilet) A tank against the wall and an oval bowl in front of it.
- Lavatory (hand basin) An oval or rectangular basin, often set in a counter.
- Shower A square or rectangle with the drain marked. A diagonal sometimes shows which way the floor falls.
- Kitchen sink One or two bowls in the counter, each with its drain.
- Floor drain A small circle or square with a grate in the floor of a CR, a laundry or a lanai.
- Cleanout An access point to clear a drain pipe, marked CO on the plumbing plan.
Kitchen and furniture
Furniture is drawn lighter than walls, to show the room works. It is not part of the building contract unless the plan says built-in.
- Range or cooktop A rectangle with the burners drawn as circles.
- Refrigerator A box marked REF, drawn at the size the space has to allow.
- Counter with cabinets above The counter edge in a solid line, and the upper cabinets dashed because they sit above the cut.
- Bed An outline with the pillows drawn at the head. It shows the room can take the bed and still be walked round.
Electrical
Electrical symbols sit on their own sheet, signed by a professional electrical engineer. Conventions vary between offices more here than anywhere, so read the legend on the sheet first.
- Convenience outlet A circle with two short lines: a wall socket. Extra marks show a weatherproof or dedicated one.
- Switch The letter S near the wall. S3 is a three-way switch, one of two that control the same light.
- Ceiling light A circle, often crossed, where a light fixture goes on the ceiling.
- Ceiling fan A small circle with blades drawn round it.
- Panelboard A rectangle, partly filled, where the circuit breakers are. Every circuit on the sheet runs back to it.
- Air-conditioning outlet Usually a box marked ACU or AC on its own dedicated circuit.
Structure and reference marks
These tie the sheets together: where the columns stand, where a section is cut, and which detail to look up.
- Column A small solid square or circle at a grid intersection.
- Beam above Two dashed lines between columns: a beam over the cut, shown so you know it is there.
- Grid line A thin line through the column centres with a numbered or lettered bubble.
- North arrow Which way is north, and so where the morning and afternoon sun will reach the house.
- Section mark A cut line with a label, such as A, matching a section drawing. The arrows show the way you look.
- Elevation marker A circle with a pointer, aimed at the wall an elevation drawing shows.
- Detail callout A dashed ring round the area, and a bubble naming the detail drawn larger on another sheet.
- Dimension A line with ticks at each end and the distance above it. The sheet states millimetres or metres.
- Room name The name of each room, often with its floor area beneath.
- Door mark A tag such as D1 by each door, keyed to the door schedule for its size and type.
- Window mark A tag such as W1 by each window, keyed to the window schedule.
- Revision mark A numbered triangle beside something changed since the last issue of the sheet. The title block lists what changed.
50 drafting conventions, drawn here to show their shape. They are conventions, not law: an office's own drawings can differ in detail, and every sheet should carry its own legend.
Who draws which symbols
A Philippine house plan is a set of sheets, and the symbols on each belong to the professional who signs it. The architectural sheets, with the walls, doors, windows, stairs and fixtures, are signed by a licensed architect. The electrical sheet, with the outlets, switches, lights and panel, is signed by a professional electrical engineer. The plumbing sheet, with the drains, cleanouts and piping, is signed by a master plumber, and the structural sheet, with columns, beams and footings, by a civil engineer. The guide to reading a house plan sets out every sheet, who signs it and the law behind it.
That is why the same light can appear twice: as a circle on the electrical sheet, and as a dashed shape on the reflected ceiling plan. Read the legend on each sheet before you read the plan. Offices differ in detail, and the sheet's own legend wins over any list, this one included.
Checking your own plan with these symbols
- Doors. Follow each arc. A door that swings into a corridor, onto a stair or into another door is a problem on paper and worse on site.
- Rooms. Take a room's length and width from the dimension lines and test it in the room size checker against the code's minimums.
- Stairs. Count the treads between the UP arrow and the next floor, and check them with the stair dimensions checker.
- Furniture. If the bed or the dining table is drawn, check there is still room to walk round it. If it is not drawn, draw it in pencil at the same scale.
- Outlets and switches. Walk through each room on the electrical sheet. Is there a switch by every door you enter through, and an outlet where the television, the refrigerator and the aircon will go?
If you are drawing a plan yourself, the guide to floor plan makers compares the tools people use and says where a drawn plan still needs an architect. For a worked example in a traditional house, the bahay kubo drawing guide has a plan, elevations and a section.
Our custom house design service draws and coordinates every sheet of a house plan, and permit and documentation assistance files it with the building office.