As-Built Survey
Documenting existing buildings as actually constructed. El-Eman Office provides as-built surveys across Egypt.
Steps in carrying out an as-built survey of an existing building
The work starts with a reconnaissance visit to establish the type of building, the number of floors and whether every room can be reached, and then the right instruments are chosen. In a survey of an existing building, a framework of control points is first set up inside and outside and tied together, and the details are measured from it. This puts every floor in one coordinate system, so the upper floors do not drift away from the ground floor.
- A total station measures corners, columns and facades with good accuracy.
- A laser distance meter is quick for interior room dimensions.
- 3D laser scanning suits complex buildings and ornate facades.
- A drone helps photograph roofs and high facades that are hard to reach.
Mistakes that weaken the survey
The surest way to spoil an as-built drawing is to rely on tape measurements alone in a large building: small errors add up and the drawing never closes on itself. Other errors come from ignoring wall and plaster thickness, so room areas differ from reality, or from forgetting to tie each floor level to one fixed reference level. Another is failing to agree the level of detail with the client in advance. Some want only walls and openings, while others want services and fittings too.
Getting the most from the deliverables
The drawings are not the goal in themselves; they are the basis for later decisions. A restoration designer builds on them without re-measuring, a quantity surveyor takes finishing and demolition areas from them, and the owner uses them to market, divide or merge units. If the purpose is to compare what was built with what was licensed, the surveyed plan is laid over the approved plan to show the differences visually.
- Define the purpose of the survey first, because it sets the accuracy and level of detail.
- Provide access to every room, roof and the basement on measurement day.
- Ask for editable DWG files as well as a PDF for printing.
- Check the drawing on site in a sample of rooms before accepting it.
When a building differs from its old plans
One of the most common reasons for an as-built survey is old plans that no longer match reality because changes were made over the years without documentation, such as a removed wall, an added room or a moved opening. Relying on those plans for renovation can bring surprises on site and change the quantities. Treat them as a first reference only and then verify them on the ground. Where there are cracks or signs of settlement, floor and ceiling levels can be added to the survey. This gives the structural engineer information on slopes and unevenness to help assess the condition, although the result cannot be decided from the drawing alone.
Frequently asked questions
How long does it take to survey an existing building?
It depends on the area, the number of floors, the complexity of the details and ease of access. A small residential building may take a day or two in the field, followed by time in the office to prepare the drawings.
Does the building have to be emptied during measurement?
Usually not, but heavy furniture or locked rooms slow the work and can hide some corners, so access should be made as easy as possible.
Will the survey reveal structural defects?
The survey records dimensions, levels and slopes and may reveal a tilt or unevenness, but it does not replace a structural inspection by a qualified engineer to assess the condition.
