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Frequently Asked Questions

1 - Q: When should I use Documenta's capabilities?

A: If your answer is yes to any of the following situations, then our experience and technologies for executing an existing-conditions, or as-built documentation, is probably the best and most cost effective solution for you.

1.1 - Do you have to obtain precise site information - as-builts - under difficult or dynamic conditions?

1.2 - Do you have to record the conditions - existing-conditions drawings - of a site that is about to be destroyed or substantially altered (such as a historic structure before demolition or partial dismantling and relocation)?

1.3 - Do you have to record site details precisely, in order to prepare as-built plans for repair or analysis (e.g. to prepare for the architectural rehabilitation of an existing structure, or for the eventuality of earthquake damage of heritage or valuable cultural items)?

1.4 - Do you have to document an object but have little up front money for preparation of as-built drawings? Aside from the cost of the equipment, most of the cost of a digital photogrammetry and / or laser scanning project goes into plotting and computer time. Taking the pictures and scanning are relatively inexpensive tasks, and the scanned point cloud and the photographic negatives can be set aside and processed as money becomes available or the need arises, as in the case of catastrophic damage.

1.5 - Do you have to survey something that is difficult to measure precisely but can be photographed? (if it can be photographed, it will be even easier to scan, as no light is necessary for laser scanning).

1.6 - Do you need to create a 3D computer model or existing-conditions drawings of an object that is difficult to measure or has many complex shapes and surfaces?

1.7 - Do you want to precisely measure the change, over time, in the shape or conditions of an object? (repetitive measurement and comparison for monitoring).

1.8 - Do you want to input the dimensions of an object into a CAD system - as-built drawings - to edit, add information, use data electronic transmission capabilities, use digital storage, make copies, rendering, animations, etc?

1.9 - Do you need to create a measurable, precise record for insurance or other purposes (as-is plans of unique artwork with dimensions and appearance)?

2 - Q: What does DOCUMENTA need to know from the prospective client in order to prepare a fixed fee proposal?

A: Please provide a sketch, a picture, or old plans that show the approximate size and height of the structure to be surveyed. It is also important that you indicate which as-built drawings or information are required (floor plans, sections, exterior elevations, interior elevations, reflected ceiling plans, rectified photographs)?.

Other relevant questions include:

a - Which is the level of details you require? Can you refer to any of our projects as a reference to what you need? 

b - Can you refer to any of our projects as being similar to your project? - in magnitude, complexity, details?  

c - Are there obstructions or any impediment for photographing and/or scanning the object or site? We have to correctly assess the site conditions, and in most cases, rely entirely on the information supplied by the client. 

Documenta considers that it is our mutual (ours and the client) responsibility to properly investigate and/or inform about all the site conditions of the project. If possible, and based on your information, we will submit a fixed fee proposal (cost, schedule, deliverables).

Back to the free quote request

3 - Q: How accurate are the as-built drawings?

A: We provide a high level of accuracy with great uniformity and consistency. The accuracy of the drawings will vary according to scale. Typically, for architectural and engineering type drawings, the precision falls within the resolution of 1/3 inch (0.6 cm). Dimensional precision in the real world ranges from 1:2,000 to 1:10,000 parts.

4 - Q: How much does it cost?

A: The cost is based on the amount of time required to complete the existing-conditions drawings and can vary greatly. Fees are primarily determined by the size and complexity of the structure and the level of detail to be represented. Project budgets over the past four years have ranged from $3,200 to $95,000. 

5 - Q: How long does it take?

A: Typical turnaround time averages 10 to 45 days. For large projects we usually can make partial deliveries as the project stages are completed. A documentation project can be done in two parts. The first step is the acquisition of the site information, which usually takes only a few hours and completely documents the object. 

The second step is the execution of the as-built drawings, which can be done immediately or when and even if the need arises. This approach is useful in preventive documentation (only photographing or scanning) of monuments or artwork, for example, that will only be completed (production of the drawing) when necessary, as in the case of natural catastrophes or accidents.

6 - Q: Can a project be too small or too large?

A: Not usually. The flexibility of our technical resources and experience with digital photogrammetry and laser scanning has allowed us to complete projects that range from documenting pieces of artwork, to residential buildings, to large buildings, to full street blocks of commercial façades.

7 - Q: How much time will you spend on site?

A: We will rarely spend more than 4 to 6 hours on a single site, depending on the size, scope of work and eventual difficulties in photographing or scanning the object. 

8 - Q: Do you need a special camera to take the photographs?
A: Yes. We use digital and analog 35 and 60 mm RolleiMetric portable metric cameras that have been calibrated for correction of optical distortions. They allow us to obtain a maximum and uniform level of accuracy.

9 - Q: Which type of scanner do you use ?

A: We utilize the Leica HDS scanner from Leica, the most versatile and modern scanner in the market. It utilizes a "time of flight" method that measures how long the laser pulse takes to hit a surface and return to the scanner. It is an incredible piece of equipment.  

10 - Q: What kind of drawing can be generated?

A: We extract precise 3D measurements from the photographs or the scanned point cloud. The resulting as-built drawing files are exported directly into CAD. This means that we can provide existing-conditions elevations, profiles, plans, sections and specific details. 

Also, although we usually observe standard architectural conventions to prepare two-dimensional drawings describing three dimensional objects (plans, sections and elevations), we are able to provide accurate 3D models which can be used as a base for visualization, volume rendering, and animation. The accuracy of the 3D information allows for the control of other complementary surveys, as a topographical survey, for example. 

11 - Q: Can you use our office's drawing conventions?

A: Yes. We ask all of our clients to specify from the beginning of a project how they would like their existing conditions drawings to be organized and graphically represented. This means that any CAD user can expect to receive drawings that will be useful the moment the files are opened (DXF, DWG - Macintosh/PC). 

12 - Q: I do not use CAD. Can you deliver plotted drawings?

A: Yes. We can deliver drawings plotted onto various media from various types of plotters. We can add your title block onto these sheets, or add notes as indicated by the client in the scope of work defined at the outset of the project.

13 - Q: Can I order copies of photographs?

A: Yes. Standard deliverables include enough photographs so that every area of the recorded subject is shown in at least three photographs. If you desire additional copies of the photographs, we will make these available to you.

Have a question?

We will be happy to answer it. Please contact us at your convenience, or submit your question on our contact form.

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