Note: Descriptions are shown in the official language in which they were submitted.
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TITLE: Computer Aided Method for Determining Discrepancies Between
Erected Structures and Approved Construction Plans
FIELD OF THE INVENTION
This invention relates to a method of determining and identifying physical
discrepancies between buildings and other erected structures and the plans for such
buildings and structures as have been approved by government or other agencies. In
particular, the invention relates to a new computer aided method of determinin~ and
10 identifying such physical discrepancies.
BACKGROUND OF THE INVENTION
Typically before the construction of buildings, whether they be commercial,
15 residential or public, detailed plans of the building are prepared and submitted to the
applopliate government agencies for approval. Once approved, the building is then
built in accordance with those approved plans and copies of the approved plans are
normally kept on file by the government agency that provided the approval. A
similar process is often carried out for other civil engineering structures including
20 bridges, roadways, towers, etc. Likewise, when significant structural or other changes
are made to existing buildings or constructions, plans for such changes are normally
prepared and approved prior to the commencement of construction. In many
jurisdictions prior approval of plans detailing the nature of the change or
improvement is a legal pre-requisite before actual construction may commence.
During construction it is quite common for various changes to be made to a building.
In some cases the changes may be extremely minor and insignificant while others
may be major and very significant. Often the changes are pre-approved by
government authorities and revised plans are prepared and filed. However, in some
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instances the final building or construction may vary significantly from that asshown in the approved plans or drawings without revised plans having been filed or
approved. Renovations or additions may also be made to a building at different
points in time. Where prior approval is not obtained for a renovation or addition the
5 approved set of plans m~int~ined by the appropriate government agencies will not
reflect such changes and will be inaccurate. As a result the "as-built" structure can
sometimes depart radically from that as depicted in the approved plans. In general,
the degree of departure between the approved plans and the actual building structure
increases over time. Where buildings and other constructions do not conform
10 precisely to the approved plans filed with municipal or other government of fices there
does not exist a plan of the as-built structure that can be readily inspected.
Furthermore, due to the uncertainty as to the accuracy of approved plans over time,
their reliability is often questionable.
15 For various implicit reasons financiers, banks, insurance companies, propertymanagers, fire departments and other services require detailed knowledge of the
structure of a building as it actually exists. Prior to the development of the present
inventive method it was necessary for individuals to obtain a copy of the approved
municipal plan and attend at the building or structure to compare the plan visually
20 with the physical structure, m~n~ lly noting changes on the approved plan. This
process was both labour intensive and resulted in unacceptable delays where updated
information was needed immediately. For example, where a financial institution is
about to advance funds on the basis of collateral taken in a building, it may not be
possible to advance such funds until an analysis of the as-built building and approved
25 municipal plans can be undertaken to ensure that the skucture meets various building,
fire and municipal regulations. Similarly, when responding to an emergency call a
fire department does not have the luxury of being able to wait until someone
performs a physical inspection of a building and then manually makes a notation of
any differences and discrepancies on the approved municipal plans.
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SUMMARY OF THE INVENTION
The invention therefore provides a new and novel method to visually identify anddetermine physical discrepancies between buildings or constructions and approved5 municipal plans. The method provides a quick, simple and reliable means to identify
such discrepancies.
Accordingly, in one of its aspects the invention provides a method of determining and
identifying common elements, discrepancies and differences between the actual floor
10 plans of buildings or other constructions and the floor plans for such buildings or
constructions as have been approved by applicable governmental or other agencies,
the method comprising the steps of; obtaining a sample or copy of said approved
floor plan for said building or construction; inputting said approved floor plan into
a computer database such that said approved plan is stored electronically in said
15 database; inspecting said building or construction and measuring and recording its
actual floor plan; inputting said measurements of said actual floor plan into said
computer database such that said measurements are stored electronically in said
database; lltili7.ill~; said computer to create an as-built image of said building or
construction floor plan, said as-built image being stored in said computer and based
20 upon said measurements of said actual floor plan; manipulating said approved floor
plan and said as-built image stored in said computer such that said approved floor
plan and said as-built image are superimposed over one another, thereby creating a
superimposed image to visually identify common elements, discrepancies and
differences between said actual floor plan of said building or construction and said
25 approved floor plan.
Further objects and advantages of the invention will become apparent from
the following description taken together with the accompanying drawings.
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BRIEF DESCRIPTION OF THE DRAWINGS
For a better underst~nding of the present invention, and to show more clearly
how it may be carried into effect, reference will now be made, by way of example,
5 to the accompanying drawings which show the preferred embodiments of the present
invention in which:
Figure 1 is a drawing of the floor plan of a hypothetical building in
accordance with the method of the present invention and represents an
approved municipal plan;
Figure 2 represents the actual floor plan of the building of Figure 1;
Figure 3 represents a drawing of a superimposed image of Figures 1 and 2
with graphical representations showing additions and deletions to the floor
plan of Figure 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
20 The method according to the present invention begins with obtaining a sample or
copy of an approved floor plan or building plan for a particular building or
construction. Such plans are normally found at the local municipal government of fice
having jurisdiction over the issuance of building permits and the construction of
buildings and other structures within a particular geographic area. These plans are
25 usually comprised of drawings of the building or structure as were submitted to local
government authorities for approval prior to construction. They may also containupdated information with respect to structural changes in the building, or lateradditions or modifications that have been made.
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Following acquisition of the approved plan or drawing, it is then electronically stored
in a computer database. While a variety of methods may be used to input the planinto the database, in the preferred embodiment the approved drawing or plan is either
input by m~nll~lly entering the information from the drawing or is input through the
5 use of a scanner or optical character reader connected to a computer. Where a
scanner is used the scanner converts the lines and representations on the plan or
drawing into an electronic format to be stored in the computer's database. Once
electronically stored in the database, commercially available computer-aided-design
(CAD) software, such as AUTOCADTM, can be utilized to edit or manipulate the
10 image of the approved drawing as required. For example, ancillary information that
may be present on the approved drawing (including title blocks, dates, approval
stamps, stray lines due to sc:~nning errors, etc.) can be deleted and the image edited
to leave only the floor plan or other structural features of the building or construction
that are of concern. Thereafter the image of the approved drawing can be viewed on
lS the computer monitor or printed for reference purposes. An example of such a
printed drawing is shown in Figure 1. Figure 1 shows a typical floor plan with
exterior walls 1, interior walls 2, doors 3, stairwell 4, and utility services 5. For
illustration purposes Figure 1 shows approved features in double outline.
20 Once the approved plan or drawing has been stored electronically in the computer
database, the actual building or construction in issue is inspected and the floor plan
and features of concern are measured and recorded. Those measurements and
features can then be input into the computer database so that they too are stored
electronically. As in the case of inputting the approved floor plan, there exists a
25 number of different methods for imputing the measurements and details of the actual
building. For example, the raw data can be directly input through the use of CADsoftware. Alternately, the building's measurements and details could be used to
manually draw a "to scale" as-built drawing. That as-built drawing can then be
scanned into the computer database with an optical character reader. Alternately,
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information from the as-built drawing can be electronically stored in the computer
through the use of a digitizer. Editing of the electronically stored drawing can then
be carried out to remove sc~nning or digitizing errors, if necessary.
5 It may also be desirable for the individual attending at the building site to identify
the location of utility services and meters, including water, electricity, gas and
telephone. The location of such utilities can be noted on the as-built drawing and can
also be input into the computer database through one of the methods discussed above.
Regardless of how the details and measurements of the physical building or structure
10 are input into the computer, once they are stored electronically the computer can be
used to create an as-built image of the building's floor plan. If necessary or
desirable, CAD or similar software can be used to manipulate or edit features on the
as-built image just as in the case of the electronically stored approved floor plan. For
illustration purposes Figure 2 shows an as-built image with the as-built structures
15 identified by cross-hatching.
After both the approved plan and the measurements of the actual floor plan have been
stored in the computer database, and after all necessary editing has been competed,
the approved plan and the as-built image can be manipulated, such that they are of
20 the same scale, and then superimposed over one another. Superimposing one image
over the other will thus create a superimposed image to visually identify commonelements and any physical discrepancies or differences between the building or
structure as it has been built and the approved plans. Whereas previously individuals
were forced to attend at the actual building site to compare the physical building
25 structure with the approved plan, through the use of the present inventive method an
actual site attendance is only necessary in order to take physical measurements of the
structure. Thereafter an inspection of any discrepancies can be carried out easily and
quickly at remote locations. No ex~min~tion or comparison of building structureswith approved drawings is necessary making the comparison simple with little chance
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of error. Superimposing the two images over one another presents a true and
accurate physical and visual representation of any differences. In addition, through
reference to the scale of the images the physical dimensions of any discrepancies or
differences can be determined quickly and with minim~l effort.
To further enhance the visual identification of any differences and discrepancies
between the actual floor plan of the building or construction and the approved plan,
in the preferred embodiment the approved plan is presented in one colour while the
as-built image is presented in a different colour. For example, the approved plan
10 could be shown in black. The as-built image could then be shown in red such that
on the superimposed image any red line that is visible (ie. not being superimposed
directly over a black line) will represent a structural difference, discrepancy or
variation from the approved plan. In this case the red lines will indicate additions
to the as-built structure that were not on the approved floor plan. The use of colour
15 in this fashion adds significantly to the ability of individuals to quickly discern
differences and discrepancies between the two images. However, it will be
appreciated by those skilled in the art that rather than utili7ing specific colours to
differentiate between the two images, a variety of other methods could equally be
employed. For example, Figures 1 and 2 show two methods of depicting approved
20 and as-built structures graphically without the use of colour.
In an alternate embodiment of the invention, the elements and features of the
superimposed image that are common to both the approved floor plan and the as-built
image are shown in a first colour. Those elements and features of the superimposed
25 image that are common to the approved floor plan but not the as-built image are
shown in a second colour. Finally, those elements and features of the superimposed
image that are common to the as-built image but not common to the approved floorplan are shown in a third colour. This has the added effect of not only visuallyidentifying the differences in the approved floor plan and the actual structure, but
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through utilization of colour as discussed, features that have been added over and
above the approved plan and those features of the approved plan that have been
removed will be instantly recognizable. That is, features shown in the first colour
represent no variance between the actual building and the approved plans. Features
5 in the second colour represent approved features that have been removed and that are
no longer physically present at the building. Similarly, those features shown in the
third colour represent additions not on the approved plans. Where desired, the
existence of any utility services or meters can be identified in a fourth or further
colours on any of the drawings or images.
Rather than showing common elements in one of 3 different colours as in the
alternate embodiment described above, graphical representations as set out in Figure
3 could equally be used. In Figure 3 the thick solid lines represent elements and
features that are common to both the approved plan and the as-built image. Double
15 outlined features are those common to the approved plan but not to the as-built
image. Finally those elements common to the as-built image but not the approved
plan are identified with cross-hatching. Accordingly, in Figure 3 cross-hatchingindicates features of the building that have been added while double 0l1tlining
signifies features that have been removed. For example walls 6 and toilet 7 are
20 shown as having been removed or non-existent. Similarly, wall 8 and door 9 have
been added over and above the features on the approved plan.
Once the approved plan and the as-built images have been superimposed over one
another the resulting superimposed image can then be printed on a single sheet of
25 paper to create a permanent superimposed drawing. The permanent record or
drawing can be provided to other individuals for purposes of assessing any physical
discrepancies or can be attached to engineering, ~ses~ment, financial or other reports
as may be necessary. The superimposed drawing can also be taken to the site of the
building or construction in order to direct an individual precisely to areas of
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discrepancies between the constructed building and the approved plan. In addition,
the superimposed drawing may provide a benefit to engineering personnel for
purposes of assessing the safety of any discrepancies or differences.
5 Since the approved plan, the as-built drawing and the superimposed drawing are all
stored in an electronic format or version, the computer database storing the data from
which these drawings are generated can be linked to a computer network that allows
other individuals to access the drawings. For example, financial institutions,
insurance companies or property managers wishing to ensure that a particular building
10 or structure complies with local building requirements and has been approved by the
requisite government authorities will be able to access the approved, as-built and
superimposed drawings stored in the database through the computer network. This
will allow them to quickly and easily inspect for any discrepancies. Accessing such
information over the computer network removes the need for individuals to eitherl S attend at local municipal of fices to review approved drawings or to physically attend
at the building or structure to measure what is actually in existence. It also allows
individuals to search for and review discrepancies from distances that are far away
from the actual building site. For buildings that must be checked or monitored
frequently, up-dated as-built images can be stored in electronic format to allow for
20 immediate visual inspection.
The present inventive method will also be of significant use to fire, police andambulance personnel. For example, when a fire, police or ambulance department
receives an emergency call to attend at a particular building or structure, they will be
25 able to utilize a computer network to access the computer database in which the as-
built, approved plan and superimposed images for the building have been
electronically stored. Accessing these drawings pursuant to the method of the present
invention will provide faster and more accurate information than would otherwise be
available. Emergency personnel will also be provided with visual identification of
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any differences or discrepancies in the as-built structure as opposed to that as shown
in municipal plans that may be on record. It will be appreciated that having up to
date information instantly available (for example new locations for stairwells, doors,
corridors, etc.) prior to attending at the building location can be invaluable to police,
5 ambulance or fire personnel when responding to an emergency call.
It is to be understood that what has been described are the preferred embodiments of
the invention and that it is possible to make variations to these embodiments while
staying within the broad scope of the invention. Some of these variations have been
10 discussed while others will be readily apparent to those skilled in the art.
