Percent of total cost released at each construction stage. Defaults are NAHB's own 2024 national cost-share survey, reordered into build sequence (site work first). Edit any percentage; the rest adjust proportionally to keep the total at 100%.
Stages sum to 100.0%
Construction loans bill interest-only during the build, and only on the money actually drawn so far, not the full amount you're approved for. This calculator spaces your draws across your build timeline using NAHB's own national cost-share data, so the interest number reflects a real drawdown, not a flat balance.
Last reviewed September 2026
| Stage | % of cost | Draw month | Draw amount | Balance after |
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Construction loans don't hand over the full loan amount at closing. A lender releases money in stages, called draws, as work is completed and inspected, and charges interest only on the amount actually disbursed so far. That principle comes straight from federal Regulation Z (12 CFR Part 1026 Appendix D): "interest is payable on the amount actually advanced for the time it is outstanding." This calculator models that month by month: your total project cost, minus your land value or down payment, gives the amount financed. That amount is released across eight construction-sequence stages (NAHB's own national cost-share breakdown, reordered from cost-rank into build order), spaced evenly across your chosen term. Each month's interest is charged on whatever has been drawn by that point, not on the full loan.
NAHB's own 2024 Cost of Construction Survey breaks a typical build into eight stages by share of total construction cost: interior finishes (24.1%), major system rough-ins (19.2%), framing (16.6%), exterior finishes (13.4%), foundations (10.5%), site work (7.6%), final steps (6.5%), and other (2.1%). NAHB publishes those as a cost ranking, not a payment schedule, so this calculator reorders them into the sequence a home actually gets built in (site work, foundations, framing, major system rough-ins, exterior finishes, interior finishes, final steps, other) for draw timing. You can edit any stage's percentage; the rest adjust proportionally so the total always stays at 100%.
Every dollar drawn accrues interest starting the month it's disbursed, at your construction loan rate. HFS Federal Credit Union's own consumer explainer puts it plainly: "Generally, a borrower will only repay interest on the loan throughout the construction phase." That means your monthly payment during the build grows as more of the loan gets drawn, unlike a standard mortgage payment that's the same every month from day one.
Many residential construction loans are one-time-close, converting automatically into a standard amortizing mortgage once the home is finished. HFS Federal Credit Union confirms "Construction Loans can typically convert to a more traditional, permanent mortgage loan upon completion of construction." If you select that option, this calculator runs the same fixed-rate amortization formula as FigureNerd's own Mortgage Payment Calculator against your fully-drawn loan amount to estimate that payment.
Draw-schedule stage percentages: NAHB's own 2024 Cost of Construction Survey, quoted from Eye On Housing, "Cost of Constructing a Home in 2024" (Eric Lynch, January 23, 2025), the same eight figures a prior FigureNerd build chain-verified against NAHB's own companion blog post. Interest-only construction billing: Consumer Financial Protection Bureau, Regulation Z Appendix D, and HFS Federal Credit Union, "What is a Construction Loan?". Construction term ceiling and default: Experian, "How Do Construction Loans Work?". Construction and permanent rate ranges: Llama Ledger, "Current Construction Loan Interest Rates (2026)" (Aron Pizow). Permanent-phase amortization formula: reused verbatim from this site's own Mortgage Payment Calculator.
Building more than one thing at once? See also the House Material Cost Calculator, the Home Building Timeline Calculator, and the Building Permit Cost Calculator for other pieces of the same project.