Measured Building Survey at Dublin Castle

Measured Building Survey at Dublin Castle

About This Project

Overview
The Office of Public Works required a Measured Building Survey of the Record Tower, Chapel Royal & adjoining State Apartments of Dublin Castle. Murphy Surveys were required to supply plans for each floor and a roof plan, as well as sections and sectional elevations in printed drawings and AutoCAD 2D drawings.

Survey Requirements
The measured survey covered the Record Tower building on all levels including the roof, Chapel Royal on all levels (excluding roof), the external courtyard between the Tower and the Cross Block and a partial survey of the adjoining State Apartments to tie to existing surveys. The external shell of the building, the roof plan and the internal rooms of the building were surveyed. On-site work had to be completed within two weeks and the work did not interrupt normal day-to-day activities and events at the castle.

The following survey detail was required:
• Floor plans and reflected ceiling plans
• All structural and architectural details
• Profiles of all joinery details
• Stone by stone survey drawings of parapet
• The roof of the Record Tower
• 10 sectional elevations
• Changes in materials

Survey Solution
Murphy Surveys used conventional survey techniques combined with 3D laser scanning technology to survey the site and buildings, capturing the required data set to produce the required deliverables for this project.  Our company was the first in Ireland to use this type of surveying technology and has used this method on many projects since 2001, including both conservation and measured building surveys.

Benefits of Laser Scanning:

  • Allows for accurate non-contact 3D capture of the site and buildings.
  • Provides a higher density of points (up to 1mm grid) with increased accuracy when compared to conventional survey techniques. Typical precision of laser scan observations is ±3mm depending on surface type.
  • The resulting point cloud is essential in order to draft accurate drawings of all features and details.
  • The Leica P20 laser scanner is the most up-to-date technology available, it can scan up to 1,000,000 points per second and can also capture high-resolution photography.
  • Once the site and building were surveyed the processing of the data was carried out in an office environment. One of the major benefits of using this method is that any queries or questions can be addressed at a later date without the need to revisit the site, as this method provides a complete 3D point cloud.
  • Further deliverables can be sourced from the point cloud: Revit models, 3D fly-through animations, orthophotos, additional cross sections (infinite number of locations) and Truviews.
MSL9048-DublinCastle_XSA-A2_Rev1-XS-A-A-2

1:50 scale cross section (vector drawing)

Client

Office of Public Works (OPW)

Survey Type

3D HD Laser Scan

Sector

Heritage / Conservation

Area

Approx. 5585 sq. m

Equipment

Leica P20 Laser Scanner

Deliverables

Floor Plans Reflected Ceiling Plans Internal Elevations External Elevations Joinery Details

Category

Case Studies, Laser Scanning & BIM