TL;DR
A 3D laser scanning scope of work fails when Level of Accuracy, Level of Development, point density, control, coverage, deliverables, and acceptance criteria are left unstated or bundled together. This guide defines all eight elements, provides a full copy-pasteable scope of work template with named blanks and suggested defaults, a vendor questionnaire with green/yellow/red answers, a spec-to-price table with a worked example, an acceptance and remedy protocol, and discipline-specific addenda for structural, MEP, architectural, and facility management teams.
TL;DR
A 3D laser scanning scope of work fails when it leaves Level of Accuracy, Level of Development, point density, control, coverage, deliverables, and acceptance criteria unstated or bundled together as vague "high accuracy" language. This guide breaks the scope into eight elements that must each be defined in writing, provides a full copy-pasteable scope of work template with named blanks and suggested defaults, a vendor questionnaire with green/yellow/red answers, a table showing how each spec variable moves field time and cost, a worked pricing example, an acceptance and remedy protocol, and discipline-specific addenda for structural, MEP, architectural, and facility management teams. For a shorter starting point, see the scope of work template for scan-to-BIM projects; this guide is the long-form reference that expands every section of that template into procurement-ready language.
Table of Contents
- Why most scanning scopes fail
- The eight things a scope must define
- The scope of work template
- The vendor questionnaire, with acceptable answers
- How the spec drives the price
- Acceptance and remedy
- Discipline addenda
- FAQ
Why most scanning scopes fail
Most scope-of-work documents for 3D laser scanning are written by people who know what they want the model to look like but have not translated that into measurable capture and modeling requirements. Three failure modes show up repeatedly, and each one has a traceable downstream cost.
No control tie specified. A scope that says the scan will be "registered to project coordinates" without naming the control network, datum, and monument list leaves the provider to register the point cloud to its own arbitrary origin or to a single total-station setup with no independent check. When the resulting model is later overlaid on a civil survey or an existing Revit model, it does not align. The fix costs a re-registration pass at minimum, and at worst a re-scan, because the original control shots were never tied to anything traceable.
Level of Accuracy and Level of Development are conflated. LOA describes how closely the captured point cloud matches physical reality; LOD describes how much geometric and non-geometric information is embedded in a modeled element. A scope that specifies "LOD 300 accuracy" is describing two different things with one term, and a bidder can legally satisfy either reading. One vendor prices a survey-grade point cloud with no modeling; another prices a fully detailed LOD 300 model built from a loosely registered scan. Both technically match the written scope. The client discovers the mismatch only when the deliverable arrives and does not support the intended use — usually MEP coordination or fabrication, both of which need the model geometry itself, not just an accurate cloud, held to a stated tolerance.
Deliverable formats are unstated. "A 3D model of the building" is not a deliverable. Without named file formats, software versions, and coordinate system per file, the client receives whatever the vendor's default export happens to be — often a single Revit file with no linked point cloud, no CAD export, and no shared coordinates file, which means every downstream consultant has to ask for a re-export before they can start work. That delay is rarely built into anyone's schedule and it lands entirely on the client's timeline, not the vendor's.
Each of these three gaps is closed by writing the eight elements below into the scope before the request for proposal goes out, not after a bid comes back low and the client tries to reconcile it against expectations that were never on paper.
The eight things a scope must define
1. Purpose and downstream use
The scope should open by stating what the scan or model will be used for, because every other decision in the document — accuracy, density, LOD, deliverable format — is derived from this one sentence. A scan intended for early feasibility massing needs neither the accuracy nor the modeling depth of a scan intended to drive steel fabrication drawings, and pricing both at the higher standard wastes budget on the feasibility study while pricing both at the lower standard produces an unusable fabrication model. State the intended use, the downstream software or process it feeds, and who the end consumer is (design team, GC, fabricator, facility management).
Scope language: *"This scan and its deliverables are intended to support [renovation design / MEP coordination / steel fabrication / facility management / litigation documentation], and all subsequent accuracy, density, and modeling requirements in this scope are set to support that use."*
2. Level of Accuracy (LOA) at a stated confidence level
LOA describes the measured deviation between the registered point cloud (or model) and physical reality, expressed as a tolerance at a stated confidence level, following the USIBD Level of Accuracy specification bands. A scope that says "high accuracy" without a number and a confidence level cannot be verified against anything after the fact — there is no basis for a pass/fail decision. State the numeric tolerance, the confidence level (typically 95%), and whether it applies to the registered point cloud, the modeled elements, or both, since these are commonly held to different tolerances on the same project.
Scope language: *"The registered point cloud shall achieve an accuracy of ±[5 mm architectural / ±6 mm industrial] at 95% confidence relative to project control, and modeled elements shall be represented within ±10 mm of the registered point cloud at the LOD specified in Section [X]."*
3. Level of Development (LOD) by discipline
LOD, as defined by the BIMForum LOD Specification, describes the reliability of geometric and non-geometric information in a modeled element at a given project stage — it is a modeling standard, not a scanning standard, and it must be assigned per discipline rather than as a single number for the whole project, because architectural walls, structural framing, and MEP systems rarely need the same level of development on the same schedule.
Scope language: *"Modeled elements shall be developed to [LOD 200 / LOD 300 / LOD 350] per discipline as follows: architectural — LOD [___]; structural — LOD [___]; MEP — LOD [___], per the BIMForum LOD Specification current edition."*
4. Point density — points/m² and mm spacing at a stated range
Point density is the single most commonly omitted spec in this market — competitor scopes describe accuracy and LOD but almost never state the density of the underlying capture, which is what actually determines whether the modeler has enough data to resolve a given element at the specified LOD. A dense scan at coarse LOD is wasted capture cost; a sparse scan at high LOD leaves the modeler filling gaps with assumptions the client never authorized.
Scope language: *"Point density shall be no less than [___] points per square meter (approximately [___] mm point spacing) at a range of [___] meters from the scanner, sufficient to support the LOD specified in Section [X]."*
5. Control and coordinate system
The scope must name the project control network the scan will be tied to, the datum, the coordinate system, the units, and the north reference, and must state whether the provider is expected to establish new control or tie into control provided by others (a civil surveyor, a previous scan, or an existing BIM model). Without this, "registered" means only that the scans are registered to each other, not to anything the client can independently verify.
Scope language: *"The point cloud shall be registered to [project control network / state plane coordinates / building grid] established by [surveyor/provider name], in [datum], [units], with true/project north as defined by [reference document], and control shall be independently verifiable by total-station check shots at not fewer than [___] locations."*
6. Coverage and occlusion allowance
Every scope needs an explicit statement of what must be captured, what may be reasonably excluded, and how occlusions (furniture, stored material, active equipment, tenant fit-out) will be handled and documented, because "scan the building" leaves the treatment of occupied, cluttered, or inaccessible areas entirely to the field crew's judgment on the day, with no record for the client to check against later.
Scope language: *"Coverage shall include [all accessible interior and exterior surfaces / specified areas per attached plan], with occlusions from fixed furniture, stored materials, and active equipment noted in a written occlusion log delivered with the point cloud; areas occluded at the time of capture are excluded from the accuracy warranty in Section [X] unless re-scanned."*
7. Deliverables
The scope should list every deliverable by name, file format and extension, the software required to open it, the coordinate system embedded in each file, and the delivery method, because a single line item such as "point cloud and BIM model" leaves format, version, and export settings entirely to the vendor's default.
Scope language: *"Deliverables shall include: registered point cloud in [.e57 / .rcp] format; BIM model in [Revit version] at the LOD specified in Section [X]; 2D deliverables in [.dwg/.pdf] format as applicable; all files delivered in [coordinate system] via [delivery method], accompanied by a deliverables manifest listing file names, formats, and checksums."*
8. Acceptance criteria
The scope must state, in advance, exactly how the client will verify the deliverable and what happens if it fails that verification — the check measurements to be taken, the sample size, the pass/fail threshold, and the remedy — because negotiating acceptance criteria after a disputed deliverable has already been submitted puts both parties in an adversarial position neither budgeted for.
Scope language: *"Acceptance shall be based on comparison of no fewer than [___] independent check measurements against the delivered point cloud and model, with [___]% of measurements required to fall within the stated Level of Accuracy; deliverables failing this threshold shall be corrected or re-captured by the provider at no additional cost within [___] business days."*
The scope of work template
The template below can be copied directly into a request for proposal or a contract exhibit. Every blank includes a suggested default and a note on what moves it away from that default — use the defaults as a starting point, not as a substitute for filling in project-specific numbers.
SCOPE OF WORK — 3D LASER SCANNING AND MODELING SERVICES
1. PROJECT IDENTIFICATION
Project name: ______________________
Project address: ______________________
Building type: ______________________
Gross square footage: ______________________ sq ft
[Default: none — required field. Drives field-day estimate; see pricing table below.]
Number of storeys: ______________________
Occupancy status during capture: [ ] Occupied [ ] Vacant [ ] Partially occupied
[Default: confirm before quoting — occupied space adds after-hours or phased-shift
scheduling and reduces achievable sq ft per field day.]
Client contact / point of contact on site: ______________________
2. PURPOSE AND INTENDED USE
Primary downstream use: [ ] Design/renovation [ ] MEP coordination
[ ] Fabrication [ ] Facility management [ ] Litigation/documentation [ ] Other: ____
[Default: design/renovation. Tighter tolerances and higher LOD apply to fabrication use.]
Consuming software/platform: ______________________
[Default: Autodesk Revit, current release minus one version.]
3. SITE ACCESS AND CONSTRAINTS
Access hours permitted for capture: ______________________
[Default: normal business hours, Mon–Fri, 7am–5pm; specify after-hours or overnight
shift windows if the building is occupied.]
Areas requiring escort or badge access: ______________________
Areas excluded from scope (if any): ______________________
[Default: none excluded; list explicitly if any area is off-limits, e.g., secure suites.]
4. SURVEY CONTROL REQUIREMENTS
Control network: [ ] Provided by client/surveyor [ ] Established by provider
[Default: established by provider using a closed traverse tied to at least two
known/recoverable points if client control is unavailable.]
Coordinate system / datum: ______________________
[Default: project-specific building grid; state plane coordinates where a georeferenced
tie is required for site/civil coordination.]
Units: [ ] US Survey Feet [ ] International Feet [ ] Meters
[Default: US Survey Feet for US building projects.]
North reference: ______________________
[Default: true north per available civil/plot plan; note if project/grid north differs.]
Independent check shots required: ______________________ (minimum count)
[Default: minimum of 10 total-station check shots distributed across the site,
or 1 per 10,000 sq ft, whichever is greater.]
5. CAPTURE REQUIREMENTS
Level of Accuracy (registered point cloud): ±______________________ mm at ______________________ % confidence
[Default: ±5 mm at 95% confidence for architectural work; ±6 mm for industrial;
tighter tolerances apply where fabrication is the downstream use.]
Point density: ______________________ points/m² (approx. ______________________ mm spacing) at ______________________ m range
[Default: density sufficient to resolve the LOD specified in Section 7 at the stated
range; confirm with provider based on scanner and site geometry.]
Coverage: ______________________
[Default: all accessible interior and exterior surfaces per attached floor plans.]
Occlusion allowance and logging: ______________________
[Default: occlusions from fixed furniture, stored material, and active equipment are
logged in writing and excluded from the accuracy warranty unless re-scanned.]
6. REGISTRATION REQUIREMENTS
Registration method: [ ] Cloud-to-cloud [ ] Control-based (total station) [ ] Hybrid
[Default: hybrid — cloud-to-cloud registration constrained and verified by
total-station control.]
Maximum acceptable registration residual: ______________________ mm
[Default: registration residual not to exceed the stated Level of Accuracy.]
Registration report required: [ ] Yes [ ] No
[Default: yes — a written registration report showing per-scan and overall
residuals is delivered with the point cloud.]
7. MODELLING REQUIREMENTS
LOD by discipline:
Architectural: LOD ______________________
Structural: LOD ______________________
MEP: LOD ______________________
[Default: LOD 200 for coordination-only projects; LOD 300 where the model drives
construction documents; discipline LOD may differ on the same project.]
Modeling software and template: ______________________
[Default: current Revit release, client-provided template if available; provider's
standard template otherwise.]
Phasing/worksets required: [ ] Yes [ ] No — describe: ______________________
[Default: single phase, single workset unless the project requires phased demolition
or renovation tracking.]
Family/content standard: ______________________
[Default: provider's standard family library; client-specific families only where
supplied by the client in advance.]
8. DELIVERABLES SCHEDULE
| Deliverable | Format | Quantity | Due Date |
|---|---|---|---|
| Registered point cloud | .e57 / .rcp | 1 set | [___ business days from capture] |
| BIM model | .rvt | 1 file | [___ business days from capture] |
| 2D drawings (if applicable) | .dwg / .pdf | [___] | [___ business days] |
| Registration report | .pdf | 1 | With point cloud |
| Deliverables manifest | .pdf/.xlsx | 1 | With final deliverable |
[Default turnaround: registered point cloud, 3–5 business days from capture;
LOD 200 model, 10–15 business days for approximately 100,000 sq ft;
LOD 300 model, 3–5 weeks. Larger or occupied sites move toward the longer end.]
9. QUALITY ASSURANCE AND ACCEPTANCE
Check measurement sample size: ______________________ (minimum count)
[Default: minimum of 20 independent check measurements, or 1 per 5,000 sq ft,
whichever is greater.]
Pass threshold: ______________________ % of measurements within stated LOA
[Default: 95% of check measurements within stated Level of Accuracy.]
Remedy for failed acceptance: ______________________
[Default: correction or re-capture at no additional cost within 10 business days
of written notice of failure.]
10. DATA OWNERSHIP AND RETENTION
Raw scan data ownership: ______________________
[Default: client owns all deliverables upon final payment; provider retains raw
scan data for [90 days / 1 year] for warranty and re-delivery purposes.]
Data retention period: ______________________
[Default: 1 year from final delivery, after which raw data may be purged.]
11. CHANGE CONDITIONS
Rate for added scope (additional sq ft, added LOD, re-scans due to client-caused
access changes): $______________________ per sq ft or $______________________ per hour
[Default: additional scope billed at the same per-sq-ft rate as the base scope,
confirmed on a written change order before work proceeds.]
12. SCHEDULE AND MILESTONES
Field capture start date: ______________________
Field capture duration: ______________________ field days
[Default: calculated at 80,000–120,000 sq ft per field day for accessible,
unoccupied space; occupied or obstructed space reduces this range.]
Registered point cloud delivery: ______________________
Model delivery (by LOD/discipline): ______________________
Final acceptance sign-off date: ______________________The vendor questionnaire, with acceptable answers
Send this to every bidder before comparing price. A single red answer on accuracy, control, or acceptance is disqualifying regardless of how competitive the price is, because those three items cannot be corrected after capture without a re-scan.
| # | Question | 🟢 Green | 🟡 Yellow | 🔴 Red |
|---|---|---|---|---|
| 1 | What Level of Accuracy do you register to, and at what confidence level? | States a numeric tolerance (e.g., ±5 mm) at a stated confidence level (e.g., 95%) | States a tolerance without a confidence level | "High accuracy" or "survey-grade" with no number |
| 2 | How do you verify registration accuracy independently of the scan-to-scan alignment? | Total-station check shots against known control, reported in writing | Verifies against a prior scan or as-built only | No independent verification method described |
| 3 | What scanner(s) will be used on this project? | Names the make/model and states its published accuracy spec | Names a scanner category (terrestrial/mobile) without a model | Will not disclose equipment |
| 4 | What point density will the capture achieve? | States points/m² or mm spacing at a stated range | Estimates density loosely | Cannot answer or has never been asked before |
| 5 | Who performs registration — in-house staff or a subcontractor? | In-house, named staff with a described QC step | Subcontracted but QC'd in-house | Subcontracted with no described oversight |
| 6 | What is your registration residual reporting process? | Written report with per-scan and overall residuals delivered as a matter of course | Available on request only | Not tracked or not reported |
| 7 | What file formats and versions do you deliver as standard? | Lists specific formats and versions (e.g., .e57, .rcp, Revit 2024) matching client need | Generic "point cloud and model" answer, format TBD | Locked into a proprietary format with no open export |
| 8 | How do you handle occluded or inaccessible areas? | Written occlusion log delivered with the point cloud | Occlusions noted verbally only | Not addressed |
| 9 | What LOD do you model to by default, and can it vary by discipline? | Names a specific LOD per BIMForum and confirms it can vary by discipline | Names one LOD for the whole model | Cannot define LOD or conflates it with accuracy |
| 10 | What is your field-day production rate for a site like this one? | Gives a stated sq ft/day range based on site conditions | Gives a single number with no site-condition caveat | No production rate offered |
| 11 | What is your typical turnaround for a registered point cloud? | States a specific business-day range | Vague "a few weeks" | No turnaround commitment |
| 12 | What is your typical turnaround for a modeled deliverable at the specified LOD? | States a specific range tied to project size and LOD | Single flat estimate regardless of size | No turnaround commitment |
| 13 | Can you scan occupied space, and how do you plan around it? | Describes phased or after-hours capture with a specific approach | Says yes with no described method | Declines occupied-space work or has no plan |
| 14 | What is your acceptance/QC process before delivery? | Internal QC pass with named checks before client delivery | Delivers first, corrects only if the client flags issues | No internal QC step described |
| 15 | What happens if a deliverable fails the client's acceptance check? | Names a specific remedy (correction/re-scan at no cost within a stated window) | Will "discuss" remedy after the fact | No remedy offered |
| 16 | Do you carry professional liability / errors and omissions coverage? | Yes, and will provide a certificate | Coverage exists but details are vague | No coverage or unwilling to confirm |
| 17 | Can you provide references for a project of comparable size and occupancy status? | Provides 2–3 relevant references | Provides references from unrelated project types | No references available |
| 18 | How do you price change orders for added scope? | Stated rate structure, confirmed in writing before work proceeds | Verbal-only pricing, no written change order process | No defined process |
| 19 | Who owns the raw scan data, and for how long is it retained? | Clear written ownership and retention terms | Ownership implied but not written | Not addressed in the proposal |
| 20 | Will the proposal reference this scope's LOA, LOD, density, and acceptance criteria directly? | Proposal quotes the scope's own language back, item by item | Proposal is a generic template with the scope's numbers inserted | Proposal ignores the scope and substitutes its own boilerplate terms |
How the spec drives the price
Every line in the scope of work has a cost consequence, and most pricing disputes trace back to a spec variable that was never written down being decided unilaterally by the low bidder. The table below shows the mechanism.
| Spec variable | Effect on field time | Effect on registration | Effect on modeling | Net cost direction |
|---|---|---|---|---|
| Tighter LOA (e.g., ±5 mm → ±3 mm) | More setups, slower scan positions, more control shots | More residual checking, tighter tolerance to close | No direct effect | Up |
| Higher point density | Longer dwell time per scan position | Larger dataset to process and register | Larger dataset for modelers to reference | Up |
| Higher LOD (e.g., LOD 200 → LOD 300) | No direct effect | No direct effect | Substantially more modeling hours per element | Up |
| Occupied vs. vacant site | Reduces achievable sq ft per field day (phased/after-hours access) | No direct effect | No direct effect | Up |
| Multiple storeys / complex geometry | More scan setups per sq ft | More scans to register and check | More elements and connections to resolve | Up |
| Broad coverage / low occlusion tolerance | More time capturing hard-to-reach or cluttered areas | No direct effect | Fewer gaps to model around assumptions | Up |
| Single discipline, single LOD | No direct effect | No direct effect | Fewer element types to model, faster pass | Down |
| Larger contiguous floor area, easy access | More sq ft captured per field day | Fewer, larger, cleaner registration sets | No direct effect | Down |
Worked example: 100,000 sq ft, four storeys, occupied, LOD 300 architectural + LOD 200 structural
Assume a 100,000 sq ft building across four storeys (25,000 sq ft per floor), occupied during capture, requiring LOD 300 architectural and LOD 200 structural.
- Field days: At an occupied-site production rate toward the lower end of the 80,000–120,000 sq ft per field day range (occupancy and multi-storey access reduce throughput), a site of this size and condition is typically captured across roughly two field days of phased or after-hours work rather than a single continuous day, since occupied floors require coordinated access windows per level.
- Registration: A four-storey, occupied dataset with control ties on each floor requires more residual-checking time than a single-storey vacant site of the same square footage; the registered point cloud is delivered on Zealot's standard 3–5 business day turnaround once field capture is complete.
- Modeling hours: LOD 300 architectural on 100,000 sq ft is the larger modeling effort in this scope and falls within the 3–5 week LOD 300 turnaround band; the LOD 200 structural component is lighter per element and would independently fall within the 10–15 business day LOD 200 band for a site of this size, but running both disciplines against the same registered cloud is typically scheduled together, with structural elements delivered first and architectural elements following through the fuller LOD 300 turnaround window.
- Turnaround: Field capture across roughly two field days, registered point cloud in 3–5 business days after capture, LOD 200 structural model within the 10–15 business day band, and LOD 300 architectural model within the 3–5 week band from the start of modeling.
Pricing for work at this scope generally falls within the $0.05–$0.20/sq ft range depending on where the final specification lands within the table above; occupancy, four storeys, and the mixed LOD 300/LOD 200 requirement all push toward the upper portion of that range rather than the lower end. A written quote reflecting the specific building and access conditions is typically returned within 24 hours of receiving the completed scope.
Acceptance and remedy
An acceptance and remedy clause is close to unwritten across this market's published scope templates, yet it is the clause that determines who absorbs the cost when a deliverable does not meet the stated Level of Accuracy. It should specify four things in writing before capture begins, not after a disputed deliverable arrives.
Verification protocol. The client or its representative selects a sample of independent check measurements — physical dimensions taken with a total station or tape at locations not disclosed to the scanning crew in advance — and compares them against the corresponding measurements in the delivered point cloud or model. A deviation map showing the distribution of differences across the sampled points gives a clearer picture than a single pass/fail number, because it shows whether any failures cluster in one area (suggesting a local registration or occlusion issue) or are distributed randomly (suggesting the overall tolerance was not met).
Percentile pass criteria. The scope should state what percentage of sampled measurements must fall within the stated Level of Accuracy for the deliverable to be accepted outright — commonly a threshold in the 90–95% range rather than 100%, since even survey-grade instruments carry a small statistical spread. Falling below that threshold triggers the remedy clause rather than outright rejection of the entire deliverable, unless the failures are concentrated enough to indicate a systemic registration problem.
Re-scan triggers. A remedy clause should distinguish between a localized correction (re-scanning or re-modeling a specific area where check measurements failed) and a full re-scan trigger (failure distributed broadly enough, or concentrated in a way that indicates a control or registration error affecting the whole dataset). The scope should state a specific failure rate or pattern that triggers the broader remedy rather than leaving that judgment to negotiation after the fact.
Who pays, and holdback tied to QC pass. Where the failure is attributable to the provider's capture or registration process, correction or re-capture should be performed at no additional cost within a stated number of business days. Where the client's own actions caused the failure — access denied to an area, furniture moved after capture without notification, or a change to occupancy that was not disclosed — the cost of re-capture should fall to the client under the change conditions section of the scope. A holdback of a stated percentage of the contract value, released only on written confirmation that the deliverable passed the acceptance sample, gives both parties a mechanism to resolve this without a dispute escalating past the project team.
Discipline addenda
The eight core scope elements apply to every project; each discipline needs additional lines layered on top of the base scope to be fully usable by its downstream consumer.
Structural addendum
- Member centerlines shall be modeled to the specified LOD, with centerline location, not surface location, as the basis of coordinate reporting.
- Camber and deflection present at the time of scanning shall be noted in the model or an accompanying report, distinguishing as-scanned condition from design/nominal condition.
- Connection detail (bolted, welded, moment, pinned) shall be modeled to the LOD specified for structural elements, with connection type noted where it affects downstream fabrication or analysis.
MEP addendum
- Hanger and support locations, and insulation outer diameter (not bare pipe/duct diameter), shall be captured and modeled where clash detection depends on installed, insulated dimensions rather than nominal pipe size.
- Clearance zones required for maintenance access, code-mandated working space, and future equipment removal paths shall be modeled or documented as a zone, not inferred from the geometry alone.
- Above-ceiling coverage shall be explicitly included in the coverage requirement (Section 6 of the template above), since above-ceiling MEP is the area most commonly under-scanned when occlusion and access are not addressed directly.
Architectural addendum
- The scope shall state whether wall dimensions and areas are measured to finish face or to structural core, since these two conventions produce materially different square footage and clearance figures for the same building.
- Where BOMA area measurement standards apply (leasing, valuation, facility management use cases), the scope shall state which BOMA standard and measurement convention governs the deliverable.
Facility management addendum
- Modeled equipment and assets intended for ongoing facility management shall be tagged with asset identifiers matching the client's CMMS or facility management system naming convention, not the provider's default family naming.
- Where a COBie deliverable is required, the scope shall state the COBie data drops required at each project stage and which non-geometric attributes (manufacturer, model number, install date, warranty period) must be populated, since COBie compliance is a data-completeness requirement independent of the model's geometric LOD.
FAQ
What is the difference between Level of Accuracy and Level of Development in a scanning scope?
Level of Accuracy (LOA) describes how closely the captured point cloud matches physical reality, expressed as a numeric tolerance at a stated confidence level, following USIBD guidance. Level of Development (LOD) describes how much geometric and non-geometric information is embedded in a modeled element, following the BIMForum LOD Specification. A scope needs both, stated separately, because a point cloud can be highly accurate while the model built from it is developed to a low LOD, or vice versa.
What accuracy should I specify for a renovation project?
Architectural renovation work is typically specified at ±5 mm registered accuracy at a 95% confidence level, with modeled elements represented within ±10 mm of the registered point cloud at LOD 300. Industrial or process-piping work is typically specified at ±6 mm given the scale and coordination tolerances involved. Fabrication-driving scopes may warrant tighter tolerances depending on the specific trade.
Can point density really be different from accuracy?
Yes. Accuracy describes how close a measured point is to the true physical location; density describes how many points were captured per unit area. A scan can be highly accurate but too sparse to resolve fine detail, or dense but poorly registered and therefore inaccurate despite the volume of data. Both need to be specified independently for the scope to be complete.
How long does it take to get a registered point cloud back?
A registered point cloud is typically delivered within 3–5 business days of the field capture being completed, assuming standard site conditions and no unresolved control or occlusion issues discovered during registration.
How long does a full LOD 300 model take?
An LOD 300 model typically takes 3–5 weeks from the start of modeling, depending on building size, discipline count, and geometric complexity. An LOD 200 model for a site of roughly 100,000 sq ft typically takes 10–15 business days.
Can occupied buildings be scanned without disrupting operations?
Yes. Occupied buildings are commonly scanned using phased access windows or overnight/after-hours shifts, coordinated with the occupant's schedule and documented in the scope's site access and constraints section. Occupancy reduces the achievable square footage captured per field day compared to a vacant, fully accessible site, so schedule and field-day estimates should account for that reduction explicitly.
What should I do if a vendor won't commit to a numeric accuracy tolerance?
Treat it as a disqualifying answer. A vendor who cannot state a numeric Level of Accuracy at a stated confidence level, and cannot describe how that accuracy is independently verified against control, has not built quality assurance into its process — the vendor questionnaire above flags this as a red answer for exactly that reason.
Who is responsible for cost if a re-scan is required?
Responsibility depends on cause. If the deliverable fails the acceptance sample because of the provider's capture or registration process, correction or re-capture is performed at no additional cost within a stated remedy window. If the failure results from a client-caused condition — undisclosed occupancy changes, denied access, or furniture moved after capture — the cost is typically billed under the scope's change conditions section. Writing this distinction into the scope before capture begins avoids a dispute over cause after the fact.
Does point density or accuracy change based on the scanning technology used?
Capture technology affects the field-of-view, speed, and achievable density at a given range, but the scope should specify the required accuracy and density outcomes rather than mandate a specific instrument, so the provider can select the appropriate equipment for the site. A mobile LiDAR system such as the NavVis VLX3, capable of 2.56 million points/sec, is suited to large, walkable interior areas where continuous capture at walking pace maintains high density across long corridors; other site conditions may call for static terrestrial scanning instead.
Should the scope of work be part of the contract or a separate exhibit?
Either works, provided the scope is incorporated by reference into the contract and the contract's payment and remedy terms point back to the scope's acceptance criteria section. Treating the scope as an informal attachment that is never explicitly incorporated leaves its accuracy, LOD, and acceptance language without contractual force if a dispute arises.