1. Project Parameters & Real-World Hazards
Configure baseline estimates and toggle documented hazards from real homeowner remodels.
Initial bid before demolition, wall-opening, and material revisions.
Pre-1990
Homes built before 1990 show significantly higher incidence of ungrounded wiring, cut framing, and plumbing decay.
$6,750
Industry standard contingency reserved before signing construction agreements.
Observed Field Hazards (Quora Contractor Cases)
3 Selected
2. Dynamic Overrun Projection
Simulated final expenditure stress-tested against active risk factors.
Adjusted Total Forecast
$64,800
Predicted Overrun: $19,800 (44.0%)
High
Recommended Contingency
25%
Buffer: $11,250
Current Buffer Gap
-$13,050
Contingency shortfall
| Baseline Contractor Bid | $45,000 |
| Unforeseen Demolition Surprises (Plumbing/Structural/Codes) | +$12,600 |
| Scope Expansion & Custom Upgrades (Feature Creep) | +$7,200 |
| Allocated Contingency (Current 15%) | $6,750 |
| Net Uncovered Out-of-Pocket Overrun | $13,050 |
Contingency Warning: Your current 15% contingency ($6,750) will be exhausted. You face an estimated $13,050 in out-of-pocket deficit. Raise your buffer to at least 25% for a house of this age and risk profile.
Includes full line-item audit and contractor negotiation checklist.
Grounded Field Overrun Sources (Quora Renovation Thread Analysis)
This simulator operationalizes recurring real-world failure patterns documented in the source Quora inquiry: "What factors can make a home improvement project more expensive than expected?"
Day 1 Foundation Excavation:
"On literally day 1 of construction, the backhoe guy digging the new foundation hit (and broke) the sewer line to the street. Clearly marked out with spray paint... hit it anyway."
Hidden Structural & Cut Studs:
"I took all the old plaster off a kitchen wall and saw that a previous owner had cut through the studs in order to run a pipe. I think the siding was the only thing holding the wall up."
Mid-Project Feature Creep:
"Problem is once the rough in is done owners change their mind how to proceed... add pricier pieces, extra pieces that may include redoing rough in."
Non-Compliant Legacy Wiring:
"We found an entire room in my house where the electrical wiring wasn't code compliant. Since the walls were open, it wasn't a big change, but it was a change."