United PDM is fully licensed and equipped to offer you a complete range of surveying services and because we have such a wide variety of options, we will definitely be able to meet your needs and deliver the satisfaction that you are looking for.

We have both the technical expertise as well as the experience to know how to handle all jobs that you need completed. We are always putting our customers first which makes us the best choice for a customer service oriented business, we will work with you closely to make sure that you get the final results you are looking for.

When you need professional surveying services completed for your property, look no further than United PDM!

  • ALTA Survey

    An ALTA survey is a boundary survey prepared to a set of minimum standards that have been jointly prepared and adopted by the ALTA/ACSM. Additionally, an ALTA survey shows improvements, easements, rights-of-way, and other elements impacting the ownership of land. An ALTA Survey is often prepared for commercial properties, as it will provide the title company with the information required to insure the title to the land and improvements to the high degree that a commercial development may require. In addition to the minimum standards set forth, a table of optional elements is included in the ALTA/ACSM standards. A careful review of the elements from the optional "Table A" is helpful in delineating a clear scope of the land surveyor's services. A current title commitment is required before an ALTA Survey can be completed.The surveyor will refer to the title commitment for the legal description of the property and for the legal description of any encumbrances (exceptions). Areas of ownership, improvements, and encumbrances will be shown graphically.

    If the survey discovers any encroachments, they should be shown graphically, and a note indicating the nature of the encroachment may also be added. The certification language of the ALTA Survey should include the names of the affected parties, including as appropriate the buyer, seller, title company, and lender. The surveyor must work in close association with the title insurance company, as the surveyor and the title company are relying on each other's work to show the matters affecting the ownership of the land and improvements in a comprehensive manner. An ALTA land survey has especially stringent requirements as developed by a joint effort of the American Land Title Association and the American Congress on Surveying and Mapping. The ALTA standards are a nationwide uniform set of standards. Sometimes referred to as the "Cadillac of surveys". The survey is specifically designed to satisfy the needs of lenders, corporations and title companies when dealing with valuable commercial properties.

  • As-built Survey

    A survey carried out during or immediately after a construction project for record, completion evaluation and payment purposes. An as-built survey is also known as a 'works as executed survey' and documents the location of the recently constructed elements that are subject to completion evaluation.

    The purpose of the As-Built Survey – also commonly called a Physical Survey – is to show the property “as it is built” at a particular point in time. While a pre-construction survey is performed to document conditions prior to construction work being performed, the As-Built survey is conducted to show the current state of the site at various stages throughout the duration of a project. It also serves as a close-out document to verify that the work authorized was completed to plans and in compliance with all relevant standards and regulations. An As-built survey builds upon the base map of a project, and includes research at local agencies, ground-level topography data and the documentation of visible site improvements. The advantage of this survey is that the new Base Map can be updated to show the current conditions of the site.

  • Boundary Survey

    Because the main objective of a boundary survey is to determine the location of land ownership lines, the initial phase includes land records research. Research is conducted at local, county and state agencies and offices for the purpose of locating deeds, plans, maps, wills and other documents defining the location and rights associated with a parcel of land. Most of this research is conducted at the Registry of Deeds, where the current parcel and abutting parcel deeds are traced back in time in order to construct a “chain of title”. This enables the surveyor to understand the original description of the parcel, as well as determine “junior-senior rights” associated with adjoining parcels.

    With the land records research complete, the surveyor can then construct a picture of what the parcel of land should look like according to the language contained in deed descriptions, as well as other documents obtained during the research. This is referred to as the “record boundaries” of the parcel.The next phase of the boundary survey involves a thorough field reconnaissance for the purpose of uncovering any boundary evidence, such as iron pipes or rods, monuments, walls, fences etc. This is a physical investigation of the parcel, and requires a keen knowledge of the types of evidence, land use patterns and local history. Reconnaissance is conducted in light of the “record boundaries”, and a determined surveyor will hunt tirelessly until the corner is found. A field survey is then conducted to locate the evidence uncovered during the reconnaissance survey.

  • Construction Layout

    Elements of a Construction Layout include: Survey existing conditions of the future work site, including topography, existing buildings and infrastructure, and underground infrastructure whenever possible (for example, measuring invert elevations and diameters of sewers at manholes); Stake out lot corners, stake limit of work and stake location of construction trailer(clear of all excavation and construction)

    Stake out reference points and markers that will guide the construction of new structures Verify the location of structures during construction; Conduct an As-Built survey: a survey conducted at the end of the construction project to verify that the work authorized was completed to the specifications set on plans.

  • Control Network Survey

    Control surveys establish a common, consistent network of physical points that are the basis for controlling the horizontal and vertical positions of transportation improvement projects and facilities. Corridor control surveys ensure that adjacent projects have compatible control. Project control surveys provide consistent and accurate horizontal and vertical control for all subsequent project surveys — photogrammetric, mapping, planning, design, construction, and right of way. The following policies, standards, and procedures are applicable to all control surveys for Caltrans-involved transportation improvement projects. This includes surveys performed by Caltrans survey staff, Caltrans consultants, local agencies, private developers and others.

    Horizontal corridor control surveys shall be performed along transportation corridors where multiple improvement projects are planned. Horizontal project control surveys shall be performed for all Caltransinvolved transportation improvement projects using California Coordinate System coordinates to define the geographic positions of project facilities. Vertical project control surveys shall be performed for each Caltransinvolved transportation improvement project that requires elevations to define the positions of fixed works.

  • Elevation Certificates

    A community's permit file must have an official record that shows new buildings and substantial improvements in all identified Special Flood Hazard Areas (SFHAs)are properly elevated. This elevation information is needed to show compliance with the floodplain management ordinance. FEMA encourages communities to use the Elevation Certificate developed by FEMA to fulfill this requirement since it also can be used by the property owner to obtain flood insurance. Communities participating in the Community Rating System (CRS) are required to use the FEMA Elevation Certificate.

    The Flood Elevation Certificate is an important tool of the National Flood Insurance Program (NFIP). It is used to certify building elevations if the building is located in a Special Flood Hazard Area in order to: Determine the proper flood insurance premium rate for the building. Support a request of a Letter of Map Amendment (LOMA) or Letter of Map Revision based on fill (LOMR-F).

     The elevation information must be submitted on the Elevation Certificate (FEMA Form 086-0-33) in effect at the time that the Elevation Certificate was completed and signed. Elevation Certificates can only be completed by a licensed land surveyor, engineer, or architect who is licensed by the State to perform such functions.

  • Hydrographic Survey

    Hydrographic survey is the science of measurement and description of features which affect maritime navigation, marine construction, dredging, offshore oil exploration/drilling and related activities. Strong emphasis is placed on soundings, shorelines, tides, currents, sea floor and submerged obstructions that relate to the previously mentioned activities.

    The term hydrography is sometimes used synonymously to describe maritime cartography, which in the final stages of the hydrographic process uses the raw data collected through hydrographic survey into information usable by the end user. Hydrography is collected under rules which vary depending on the acceptance authority. Traditionally conducted by ships with a sounding line or echo sounding, surveys are increasingly conducted with the aid of aircraft and sophisticated electronic sensor systems in shallow waters.
  • Machine Control Data Processing & GPS Site Calibration

    A site calibration is a series of mathematical computations that transform WGS84 coordinates into local grid coordinates. A GNSS receiver measures WGS84 latitude, longitude, and ellipsoidal height coordinates to determine its location, however, surveyors typically use a local grid coordinate system. To benefit from the increased accuracy of modern RTK GNSS surveying, the WGS84 coordinates need to be translated into local grid coordinates. This can be accomplished by working in a pre-defined coordinate system with known control, or by performing a GNSS site calibration. Essentially, a GNSS site calibration establishes the relationship between WGS84 latitude, longitude, and ellipsoidal height, with the needed local northing, easting, and elevation. A site calibration typically consists of a horizontal and a vertical adjustment.

    The horizontal adjustment is a least squares best fit to make the GNSS derived grid coordinates fit, as closely as possible, to the local control grid coordinates. The parameters resulting from this are a rotation, translation, and a scale of the GNSS coordinates. The vertical adjustment can be done with or without a geoid model. If you do not have a geoid model, a simple vertical shift as a single point can be applied, or and inclined plane can be computed using the orthometric heights of the local control.

  • Specific Purpose Survey

    Surveys which are performed for a purpose other than the purposes encompassed by the definitions in the paragraphs below shall be permitted only where unusual conditions make impracticable or impossible the performance of one of the types of surveys

    (a) Such purpose and conditions shall be clearly shown upon the survey map or in the survey report.
    (b) Surveys performed for purposes of monumenting, referencing, describing, and mapping centerline or baseline may be performed as Specific Purpose Surveys.Additionally, surveys performed for the purpose of monumenting official right-of-way lines may be performed as Specific Purpose Surveys.

  • Terrain Modeling

    DTM is often used as a generic term for DSMs and DTMs, only representing height information without any further definition about the surface Other definitions equalise the terms DEM and DTM,or define the DEM as a subset of the DTM, which also represents other morphological elements.

    There are also definitions which equalise the terms DEM and DSM.On the Web definitions can be found which define DEM as a regularly spaced GRID and a DTM as a three-dimensional model (TIN).[7] Most of the data providers (USGS, ERSDAC, CGIAR, Spot Image) use the term DEM as a generic term for DSMs and DTMs. All datasets which are captured with satellites, airplanes or other flying platforms are originally DSMs (like SRTM or the ASTER GDEM). It is possible to compute a DTM from high resolution DSM datasets with complex algorithms (Li et al., 2005). In the following the term DEM is used as a generic term for DSMs and DTMs.

  • Topographic Survey

    Topography is a field of geoscience and planetary science comprising the study of surface shape and features of the Earth and other observable astronomical objects including planets, moons, and asteroids. It is also the description of such surface shapes and features (especially their depiction in maps). The topography of an area could also mean the surface shape and features themselves. In general, topography is concerned with local detail in general, including not only relief but also natural and artificial features, and even local history and culture.

    This meaning is less common in America, where topographic maps with elevation contours have made "topography" synonymous with relief. The older sense of topography as the study of place still has currency in Europe. Topography in a narrow sense involves the recording of relief or terrain, the three-dimensional quality of the surface, and the identification of specific landforms. This is also known as geomorphometry. In modern usage, this involves generation of elevation data in digital form (DEM). It is often considered to include the graphic representation of the landform on a map by a variety of techniques, including contour lines, hypsometric tints, and relief shading

United PDM

427 Gaston Foster Road, Suite E Orlando, FL 32807


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At United Positioning & Digital Modeling Inc. , we believe in not only offering the best Orlando surveying and digital modeling services available, but also to help our customers learn more about our practices, so that they can be confident on the work being accomplished every step of the way.

Our team of skilled Orlando Surveyors have years of experience working on both smaller and larger construction projects.