S F Johnson Consulting, LLC
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Division 02

Division 02

📍 Division 02 — Existing Conditions

Survey, verify, protect, and remove. Use this to scope selective demo, utility locates, hazardous materials, cutting & patching, and unforeseen conditions. Always coordinate with your Division 01, drawings, specs, and AHJ.

🧭 Scope Overview (What Div 02 Covers)

  • Existing site & building surveys, documentation, **SUE quality levels**, and field verification.
  • Selective demolition & removals; **cutting & patching**; protection of existing to remain.
  • Hazardous materials identification (asbestos, lead, PCB, mold) and abatement coordination.
  • Underground/overhead utilities: one-call (811), potholing, mapping, separation, abandonment.
  • Subsurface/USTs, contaminated soil, groundwater, dewatering & discharge controls.
  • Temporary shoring/bracing/protection, vibration & crack monitoring where required.

📐 Surveys & SUE

  • SUE Quality Levels: QL-D records, QL-C visible surface features, QL-B geophysics, QL-A pothole (exact).
  • Verify benchmarks, grids, elevations; reconcile to plans before work.
  • Laser scan or as-built measure critical areas (shafts, MEP rooms, existing chases).
  • Document existing cracks/finishes (photo log) before demo or heavy work.

🛡️ Protect Existing to Remain

  • Protection plan: barriers, temp walls, floor/finish protection, signage.
  • Vibration monitoring (where specified): set thresholds & baseline readings.
  • Shutdowns & tie-ins: schedule windows, notify stakeholders, LOTO.
  • Weatherproofing continuity at temporary openings and penetrations.

⚠️ Hazardous Materials (ID Only)

  • Owner/consultant provides survey for asbestos, lead-based paint, PCBs, mold.
  • No disturbance until survey & abatement complete; isolate areas; negative air if needed.
  • Chain of custody for samples; clearance reports before re-occupancy.

🧰 Utilities: Locate • Verify • Protect

  • Call 811; markouts must be current; white-line proposed digs.
  • Pothole/QL-A where conflicts suspected (duct banks, gas, water, fiber).
  • Maintain required separations; sleeves & encasements at crossings.
  • Cap & abandon per utility owner; record abandonments on as-builts.

🧱 Selective Demo / Cutting & Patching

  • Demo plan: scope notes, limits, salvaged items, temp support, waste streams.
  • Sawcut control joints; fire watch for hot work; dust & noise controls.
  • Patch to match: thickness, profile, finish, paint sheen; mock-ups where required.
  • Coordinate with trades: penetrations, sleeves, embeds, in-wall backing.

🌍 Subsurface • USTs • Environmental

  • Geotech report: soil types, groundwater, rock, bearing, excavation support.
  • USTs/contaminated soils: permits, disposal manifests, special handling.
  • Dewatering: discharge permits, filtration (sed bags, frac tanks), BMPs.

🧮 Quick Math & Estimating Shortcuts

Cut/Remove Slab (CY)

CY = L × W × T(ft) ÷ 27. (6" = 0.5 ft)

Wall Patch (SF)

SF = Perimeter × Height − openings. Add 10–15% for feathering.

Contaminated Soil (CY)

CY = L × W × Depth ÷ 27. Add 15% swell for haul.

Potholes/Exploratories

Qty = # openings; each = L × W × D for CY + backfill & patch unit costs.

Pump Sizing Cheat

1 cfs = 448.8 gpm • 1 gpm = 0.00223 cfs. Size to peak inflow + 20% contingency.

Allowances

Carry lines for unforeseen: potholing, exploratory cuts, minor abatement, extra patching.

📦 Pre-Work Package

  • Existing conditions survey + SUE plan + utility markouts.
  • HazMat survey & abatement plan (if applicable).
  • Protection plan, demo plan, logistics drawings.
  • Photo log (date-stamped) and crack maps where required.

🧾 During Work

  • Daily reports: manpower, quantities, photos, discoveries.
  • RFI/ASIs for unforeseen conflicts; update as-builts weekly.
  • Waste tracking: manifests for HazMat, tickets for haul/landfill.
  • Monitoring logs: vibration, air (abatement), noise if specified.

🎯 Turnover

  • As-built drawings with abandoned/relocated utilities.
  • Closeout reports: abatement clearance, disposal manifests.
  • Final photo log verifying protection & patch quality.
  • Updated damage/repair list signed by Owner/CM.

📝 Self Test

  1. List the four SUE quality levels and which one gives exact vertical & horizontal location.
  2. What must be completed before disturbing suspect materials (asbestos/lead/PCB/mold)?
  3. How do you calculate cubic yards of a 25' × 8' trench at 5' deep?
  4. Name two required elements of a protection plan for existing to remain.
  5. What documentation proves utilities were properly abandoned?
  6. Give two triggers for issuing an RFI during selective demo.
  7. What is the quick conversion between cfs and gpm for dewatering?
  8. How should patches be specified to match adjacent finishes?
  9. Which call must be made before any excavation in the U.S.?
  10. What allowance lines are smart to carry for unforeseen existing conditions?

Answers: (1) QL-D records, QL-C surface features, QL-B geophysics, QL-A potholing (exact). (2) HazMat survey & required abatement/clearance. (3) 25×8×5 ÷ 27 ≈ 37 CY (plus swell). (4) Barriers/temp walls & floor/finish protection (others: vibration monitoring, signage). (5) Utility owner approvals, caps/photos, as-built locations. (6) Unknown utilities/structure conflicts; differing conditions vs. plans. (7) 1 cfs = 448.8 gpm (1 gpm ≈ 0.00223 cfs). (8) Match thickness/profile/texture/sheen; mock-up if required. (9) Call 811. (10) Potholing/exploratories, minor abatement, extra patching/backfill.