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Construction Loan Calculator

Building a home? Model your interest-only construction payments, see the draw schedule, and estimate your permanent mortgage payment after completion.

What you'll need

  • Estimated construction cost
  • Land cost (or 0 if already owned)
  • Down payment amount
  • Construction loan interest rate
  • Expected build duration
  • Permanent mortgage rate and term

What you'll get

Total construction interest

Estimated cost during build phase

Draw schedule breakdown

5-stage disbursement model

Permanent monthly payment

P&I after construction completes

Total project cost

Down + interest + mortgage payments

How It Works

1

Enter project cost

Input total construction budget including land, permits, materials, and labor.

2

Set draw schedule

Construction loans disburse in draws — interest accrues only on amounts drawn.

3

See interest during construction

Get monthly interest costs during the build phase and conversion to permanent loan.

Construction Loan Interest by Draw Schedule

Draw StageDrawn AmountMonthly Interest (7.5%)
Foundation$80,000$500
Framing$160,000$1,000
Rough-in$240,000$1,500
Final (100%)$400,000$2,500

Interest-only during construction. Convert to 30-year mortgage at completion.

Frequently asked questions

How does a construction loan work?

A construction loan is a short-term loan that funds building a home. Unlike a mortgage, funds are disbursed in stages called draws as construction milestones are completed (foundation, framing, rough-in, drywall, completion). You pay interest only on the money drawn, not the full loan amount. After construction is complete, you either convert to a permanent mortgage (construction-to-permanent loan) or pay off the construction loan with a new mortgage.

How is interest calculated on a construction loan?

Construction loan interest is calculated only on the disbursed balance, not the total approved amount. For example, if you've drawn $100,000 at 9%: $100,000 × (9% ÷ 12) = $750/month. After the next draw of $80,000 (total $180K): $180,000 × 0.75% = $1,350/month. Interest payments grow as construction progresses — lowest at the start, highest near completion.

What is a draw schedule for a construction loan?

A draw schedule is the plan for disbursing construction loan funds in stages tied to building milestones. Typical draws: 10% at closing/land, 15% at foundation, 25% at framing, 25% at mechanical rough-in, 25% at drywall and completion. Each draw is inspected and approved by the lender before funds are released.

What is the difference between a construction-to-permanent loan and a stand-alone construction loan?

A construction-to-permanent loan (also called a one-time-close) automatically converts to a regular mortgage once construction is complete — one closing, one set of fees. A stand-alone construction loan must be paid off (or refinanced) with a separate mortgage after completion, requiring two closings and two sets of fees. One-time-close loans are simpler but may have slightly higher rates.

Planning a new build?

Calculate Build Costs →