AI plumbing estimating with every count traceable.
Plumbing bids come from fixture counts, pipe by system and size, and equipment, spread across plans, riser diagrams, isometrics, schedules and Division 22 specs. AI takeoff can propose those counts and runs with the source sheet attached. Your estimator still reviews every row, applies labor units and owns the price.
Send one plan set. See what the AI extracts and what it flags for review. No obligation.
- Fixtures vs. schedule
- Pipe by system and size
- Risers and equipment
- Code sanity check
What gets counted
| Item | Unit | Source |
|---|---|---|
| Fixtures | Count by tag/type | Plans and fixture schedule |
| Domestic water (cold, hot, recirc) | LF by size and material | Plans, risers, isometrics |
| Sanitary waste and vent | LF by size and material | Plans, risers |
| Storm | LF by size; roof and overflow drains each | Roof and plumbing plans |
| Underground | LF below slab; trenching often separate | Underground plans |
| Fittings and valves | Each by type and size | Isometrics, details |
| Equipment | Water heaters, pumps, tanks, interceptors each | Equipment schedule |
| Specialties | Cleanouts, floor drains, hose bibbs, trap primers, backflow preventers | Plans, details, spec |
| Gas piping | LF by size (if in scope) | Plans, risers |
Fixture counts vs. code minimums
Fixture counts come from the drawings, not the code. But a quick check against the minimum plumbing fixture table helps you catch a missing restroom group or a schedule that doesn't match the plans. That table is IBC Table 2902.1, which mirrors IPC Table 403.1. Designing to code is the engineer's job; this is only a check.
Occupant load split 50/50 by sex → 60 per sex
Water closets: 1 per 25 for the first 50, 1 per 50 for the remainder
60 → 2 + 1 = 3 per sex (6 total)
Lavatories: 1 per 40 for the first 80, 1 per 80 for the remainder
60 → 2 per sex (4 total)
Drinking fountains: 1 per 100 → 120/100 → 2
Service sink: 1
If the plans show only 4 water closets for this occupant load, ask before you price.
Your jurisdiction's adopted code edition, amendments and permitted urinal substitution can change these numbers.
Where plumbing bids go wrong
- Schedule vs. plan counts. Count tags on plans and reconcile them with the schedule. When they differ, issue an RFI or state your assumption.
- Risers. Vertical pipe doesn't show its length on plan views. Use riser diagrams and floor-to-floor heights.
- Fixture carriers and supports. Wall-hung fixtures need carriers, which are often only on the schedule or in the spec.
- Underground. Trenching, backfill, saw-cut and patch of existing slab, and testing are often priced separately.
- Material by size. Specs often switch material (e.g. PVC vs. cast iron, copper vs. PEX) by system, size or location, such as plenum spaces.
- Testing and disinfection. Pressure tests, water tests and potable water disinfection are spec line items.
- Who carries what. Gas, med gas, roof drains vs. roofing, and equipment set vs. connect. Spell out scope in your proposal.
What it can and can't do
Can help with: counting tagged fixtures and equipment, proposing pipe runs by system and size, and keeping every quantity linked to the sheet it came from for review.
Still yours: reading spec material breaks, deciding on fittings and allowances, labor units and crew productivity, supplier pricing, exclusions, and final approval. AI output is a draft. Pricing starts only after an estimator accepts it.
When it doesn't apply: small service and residential remodel work without drawings, or design-build jobs where you size the systems yourself.
From plan set to reviewed quantities.
AI-powered, human-approved. Each stage records what ran, what changed and who approved it.
Send one plan set
Upload plumbing plans, riser diagrams, the fixture and equipment schedules, isometrics if you have them, and the Division 22 spec sections. Add an addendum if you have one.
AI proposes quantities
Counts, lengths and areas come back with the source sheet and location attached to every row.
Estimator review
Low-confidence items surface first. Your estimator accepts, corrects or rejects each one.
Map to your assemblies
Approved quantities map to your items, assemblies and estimating assumptions.
Price reviewed rows
Labor units, material pricing and supplier quotes apply only to rows that passed review.
Hand off with evidence
Reviewed quantities move on to your estimate, catalog or quote workflow with the source trail still attached.
Supported files and tasks depend on your trade and implementation. Confirm them in the free sample run.
The AI drafts. Your estimator decides.
Speed is easy to promise. Defensible numbers are the job, so RenderDraw keeps the estimator in control of every quantity that gets priced.
- Source on every row. Each quantity keeps its source sheet, location and reviewer decision.
- Lowest confidence first. The review queue shows the drawing tile with the detection highlighted and the extracted value.
- Uncertain items flagged, not hidden. Anything the AI can't confirm goes to the estimator rather than being guessed.
- Nothing priced before approval. Rows move on to pricing only after they are accepted.
Questions estimators ask.
Can AI do a plumbing takeoff?
AI can propose fixture counts and pipe runs by system and size from plans and risers. An estimator should review every quantity before pricing.
What is included in a plumbing takeoff?
Fixtures, domestic water, sanitary waste and vent, storm, underground, fittings and valves, equipment, specialties such as cleanouts and floor drains, and gas piping if it's in scope.
How do I check fixture counts?
Reconcile plan tags with the fixture schedule. For a sanity check, compare against the minimum fixture table in IBC Table 2902.1 / IPC Table 403.1 for the occupancy and occupant load.
What are common plumbing estimating mistakes?
Missed riser lengths, schedule/plan count mismatches, missing fixture carriers, underground scope gaps such as trenching and slab patch, and material changes by size or location.
How do I try RenderDraw on a plumbing job?
Send one plan set for a free sample takeoff. Each proposed quantity comes back with its source sheet for your estimator's review.
See what the AI reads on your own drawings.
Send one representative plumbing plan set. RenderDraw reviews it and follows up with what the AI extracted and what it flagged for review. Your files remain private while the request is assessed, and there is no obligation.
- Upload plumbing plans, riser diagrams, the fixture and equipment schedules, isometrics if you have them, and the Division 22 spec sections.
- RenderDraw reviews the set and the scope you want tested.
- We follow up with extracted quantities, flagged items and next steps.
Where these numbers come from
We checked this guide against the standards, manufacturer documents and industry references below (last reviewed November 2026). Figures marked as rules of thumb are typical ranges, not requirements; your project documents, local code and your own cost history govern.
- IBC 2021 §2902.1 Minimum Number of Fixtures (UpCodes, Illinois adoption) — occupancy fixture ratios
- Trimble AutoBid Mechanical — plumbing and mechanical estimating software
- FastEST FastPIPE — plumbing estimating software