Substitution Cost Calculator

Substitutions during construction add costs beyond price delta. This calculator sizes full impact.

Original item cost

Substitute cost

Architect review fee

Re-submittal cost

Schedule delay days

Daily carry

Net substitution impact

-$7,500

Price savings

$7,000

Total friction cost

$14,500

How the math works

Net = price savings − friction (review + re-submittal + carry during delay).

Small substitutions ($5-10k savings) often net to zero or negative after friction. Substitute only when savings clear $15k+ threshold or material is unavailable. Rejected substitutions eat fees regardless.

How to Use

Enter original item cost.
Enter substitute cost.
Enter architect review fee.
Enter re-submittal cost.
Enter schedule impact days.
Enter daily carry.
Read total substitution impact.

Frequently Asked Questions

Why substitute?

Original unavailable (long lead). Cost savings. Quality upgrade. Each substitution path has different math — calculate carefully.

Hidden costs?

Architect review fees ($500-$2k). Engineering revisions ($1-5k). Re-shop drawings ($500-3k). Schedule delay impact ($1k+/day). Often doubles obvious price delta.

Process?

Submit formal substitution request. Track architect review time. Document schedule impact. Keep change orders clean — poor paper trail kills contractor claims later.

How often should I rerun this?

Rerun this calculator whenever inputs change materially — new rent roll data, rate moves, loan balance updates, or quarterly operating data. For active deals, monthly refresh is typical. For stabilized assets under monitoring, quarterly is fine. Treat the output as a decision tool, not a one-time answer — market conditions evolve and so should your analysis.