If you are planning to alter, extend or convert a building, you may be tempted to save money by using old drawings, sales particulars or a sketch from a previous project. It is a false economy. The drawings of the existing building are the foundation for the planning application, the design, the specification and the contractor’s price. If they are wrong, every later stage inherits the error.
Why old drawings let you down
- Buildings are altered over the years, often without records. Walls move, openings are blocked and floors are levelled.
- Older buildings are rarely square or plumb. Walls lean, floors slope and rooms are not quite the size they appear.
- Drawings prepared for a planning application are often schematic and were never meant to be built from.
The result can be a design that does not fit, a planning drawing that misrepresents the building, or a contractor claiming extra cost when the real dimensions emerge on site.
What a measured survey provides
A measured building survey records the building as it actually is. Depending on the project it can include:
- floor plans of every level, with wall thicknesses, openings and levels
- elevations of each face of the building
- sections through the building showing floor and ceiling heights
- roof plans
- a site survey showing boundaries, neighbouring buildings and levels
The level of detail should match the purpose. A simple extension needs less than the conversion of a listed building.
Historic buildings
For listed buildings and buildings in conservation areas, accurate drawings do more than support the design. They show the planning authority exactly what is there and what will change, which is the heart of any application for listed building consent. Recording joinery, plasterwork and other features before work starts also protects them during the project.
Getting it right
- Commission the survey before design begins, not alongside it.
- Agree the scope and the level of detail at the outset.
- Make sure the designer works from the survey, and that it is issued with the tender.
Our Planning and Heritage and Building Surveys services start with an accurate record of the building. See how we took a Grade I listed town house from consent to completion.