A floor plan is a horizontal section cut about 1.2m above the floor, looking down. That definition decides what belongs on it — and it is why an estate agent's marketing plan, drawn to fill a page rather than to a scale, cannot be used to apply for anything or to build from.
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Wall positions and thicknesses, door and window openings with their swing directions, stairs with the direction of travel, level changes, fixed sanitaryware and kitchen runs, structural openings, and the position of drainage. It carries a scale bar, a north point, room dimensions and a drawing number.
What separates a usable plan from a decorative one is that it is measured and drawn to a stated scale — 1:50 for a house plan, 1:100 for elevations. A marketing floor plan is drawn to fit a portrait page and is frequently out by 100mm or more per room, which is fine for choosing a sofa and useless for ordering a steel.
Every planning and building control submission in England is judged on the difference between two states. The existing plan records the building as it stands; the proposed plan shows it after the work. An officer assesses the delta — the added footprint, the changed openings, the altered relationship to the boundary — so a proposal drawing on its own cannot be assessed at all.
The same pairing does the work in a Lawful Development Certificate application under section 192 of the Town and Country Planning Act 1990, where the whole argument is that the change between the two states stays inside permitted development limits: 3m beyond the original rear wall on a terrace or semi, 4m on a detached house, 4m maximum height, 3m within two metres of a boundary.
‘Original’ means as the house stood on 1 July 1948, or as first built if later — not as you bought it. On a London terrace that has already been extended once, the existing plan is what establishes how much of the allowance is left.
The constraints usually design the plan before taste does. Where the structure lands decides how open the ground floor can be. Where the drainage runs decides where a bathroom or utility can go without a pumped waste. Where the stair arrives decides the circulation on both floors, and Part K fixes its geometry: a maximum 42° pitch, 220mm minimum going, and 2m headroom.
Fire adds its own rules to the plan rather than to the elevation. Once a floor sits more than 4.5m above ground level — the point a loft conversion usually crosses — Part B requires a protected escape route, FD30 doors to habitable rooms off it, and an escape window of at least 0.33m² clear openable area.
A measured survey with existing floor plans is £540, delivered in five to eight working days. If you are proceeding to an application, the planning package at £840 includes both existing and proposed plans, elevations and the site and block plans, and the survey fee is folded into it rather than charged twice.
Combined planning and building regulations work, including structural calculations, is £1,750. Every fee is fixed at instruction. Council fees are separate: £258 for a householder application, £129 for a certificate.
No. Marketing plans are drawn to fill a page rather than to a stated scale, routinely carry errors of 100mm or more per room, and omit wall thicknesses, levels and drainage. A council validates against scaled drawings with a scale bar and north point, and an application submitted on a marketing plan is normally returned before the eight-week clock starts.
1:50 for floor plans and sections, 1:100 for elevations, 1:500 for the block plan and 1:1250 for the site location plan. Those are the scales English councils expect for a householder application, and using the wrong one is a common and entirely avoidable cause of invalidation.
Yes. The plans have to be measured, and on London housing stock the measurements are rarely what you would predict: wall thicknesses vary within one property, floor levels step between the original house and later rear additions, and the boundary is often not where the fence is.
Five to eight working days for a measured survey with existing plans. A full planning package including proposed plans, elevations and site drawings is 14 to 20 working days from the survey.
Not on the planning set — that is deliberate. Structural information belongs on the building regulations drawings and in the structural calculations, where beam sizes are derived from actual loads and checked against a deflection limit of span/360. A planning plan showing invented beam positions misleads whoever prices from it.
Send the address. We will confirm a fixed fee and a survey date the same working day.
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