# Construction Mortgages in Canada: 2026 Guide to Progress Draws, CMHC Rules & Lender Requirements

> Building a home in Canada requires a specialized financing product that works very differently from a standard purchase mortgage. This guide explains how Canadian construction mortgages work in 2026 — including progress draw structures, minimum down payment requirements (typically 20–25%), provincial holdback obligations under lien legislation, interest-only payment periods during construction, and how your loan converts to a standard amortizing mortgage at completion. Whether you're working with a licensed contractor or managing an owner-builder project, understanding these rules upfront can save you thousands and prevent costly delays.

Category: Financing
Last verified: 2026-04-14
Source: https://ratellow.com/guides/construction-mortgages-canada

## TL;DR
- Construction mortgages release funds in 4–5 progress draws tied to verified build milestones — you pay interest only on amounts advanced, not the full loan.
- Most borrowers need 20–25% down. CMHC mortgage insurance may allow lower down payments, but only for homes built by an approved licensed contractor — not owner-builder projects.
- Provincial lien legislation (e.g., Ontario's Construction Act) requires lenders to hold back 10% of each draw until the lien period expires — plan your contractor payment schedule accordingly.
- During construction you make interest-only payments; at completion, the loan converts to a standard amortizing mortgage and your full principal-plus-interest payments begin.
- Always budget a 10–15% contingency reserve for cost overruns — lenders expect this and may require evidence of contingency funds before approving your application.

## Construction Mortgages in Canada: 2026 Guide to Progress Draws, CMHC Rules & Lender Requirements
Building a custom home in Canada requires a specialized mortgage product that works very differently from a standard purchase mortgage. Instead of receiving the full loan amount upfront, funds are released in stages — called progress draws — as construction milestones are completed and verified by a lender-approved inspector. During this draw period, you typically make interest-only payments on the funds advanced so far, which keeps your carrying costs lower while the build is underway. Once construction is complete, the loan converts to a standard amortizing mortgage and your regular principal-plus-interest payments begin. Understanding how draws work, what holdback amounts are required under provincial law, and how your payments change at conversion is essential for a smooth, on-budget build.

- **Progress Draws Release Funds in Stages**
Construction mortgages typically release funds across 4–5 milestones: lot purchase, foundation, framing, lock-up (exterior complete), and final completion. Each draw requires a lender-ordered inspection confirming the milestone has been met before funds are released. *How this helps you:* You only pay interest on the funds drawn to date — for example, if $200,000 of a $500,000 construction loan has been advanced, your interest-only payment is calculated on $200,000, not the full amount.
- **Minimum 20% Down Payment for Most Borrowers**
Unlike standard purchase mortgages, most construction mortgages require a minimum 20–25% down payment. Canada Mortgage and Housing Corporation (CMHC) mortgage insurance may allow a lower down payment — but only for homes built by an approved, licensed contractor under a fixed-price contract. Owner-builder projects (where you manage construction yourself) do not qualify for CMHC-insured low down payment programs and typically require 20–25% or more. *How this helps you:* Knowing this distinction early lets you plan your savings strategy and choose the right build structure.
- **Provincial Holdback Requirements Protect You and Your Trades**
Under provincial lien legislation — such as Ontario's Construction Act — lenders are required to hold back 10% under provincial lien legislation until the lien period expires, usually 45 days after substantial completion. This holdback protects subcontractors and suppliers from non-payment and cannot be waived. *How this helps you:* Factor holdbacks into your cash flow plan — your contractor will not receive 100% of each draw immediately, which can affect their payment schedules to subtrades.
- **Interest-Only Payments During Construction**
During the draw period, you make interest-only payments on the cumulative amount advanced — not the full loan amount. For example, on a $600,000 construction mortgage at 6.5%, if $150,000 has been drawn, your monthly interest payment is approximately $812. Payments increase with each new draw. *How this helps you:* Your carrying costs are manageable during the build, but you should budget for rising monthly payments as draws progress.
- **Completion Conversion to a Standard Mortgage**
At project completion, your construction mortgage converts to a standard mortgage — fixed or variable rate — and your regular amortized principal-plus-interest payments begin. Some lenders charge a conversion fee of $500–$1,500. The rate you convert at may differ from your original construction rate, depending on your lender's terms. *How this helps you:* Plan for this transition well in advance — your monthly payment will increase significantly once amortization begins, and you may want to lock in a rate before completion.

## Strategy & FAQ
Construction mortgage underwriting in Canada involves materially different risk parameters and documentation requirements compared to standard residential lending. Key considerations for broker and lender professionals include: **Loan-to-Value (LTV) limits** — most Schedule A lenders cap construction advances at 75% LTV on an as-complete appraised value basis, with some monoline lenders extending to 80% LTV for contractor-built projects with fixed-price contracts. **CMHC Progress Advance Mortgage eligibility** is restricted to homes built by CMHC-approved contractors; owner-builder applications are ineligible for CMHC insurance and must be underwritten on a conventional basis. **Draw inspection requirements** — each progress draw requires a third-party inspection report (typically from an appraiser or quantity surveyor) confirming milestone completion before funds are advanced; lenders will not release draws without a satisfactory inspection. **Provincial holdback compliance** — under legislation such as Ontario's Construction Act, a statutory 10% holdback must be retained from each draw until the lien period expires (generally 45 days post-substantial completion); brokers should confirm lender holdback administration procedures at commitment. **Interest-only draw period** — borrowers service interest only on cumulative advances during construction; brokers should stress-test client cash flow across all draw stages, not just at full advance. **Lender appetite** — construction lending appetite varies significantly; credit unions and some regional lenders are more active in self-build and custom construction files than major banks, which generally prefer contractor-built projects with fixed-price contracts and builder warranties (e.g., Tarion in Ontario). Cost overrun provisions and contingency reserves (typically 10–15% of total project cost) are standard underwriting expectations.

### How do progress draws work and what triggers each release?
Progress draws are released at pre-defined construction milestones, typically: (1) Lot purchase/excavation, (2) Foundation complete, (3) Framing/roof, (4) Lock-up (windows, doors, rough mechanicals), (5) Completion. Each draw requires a third-party inspection report confirming the milestone. The lender holds back 10% until lien period expires (usually 45 days post substantial completion). Draw schedules vary by lender — some offer 3-draw, others 5-draw programs.

### Can CMHC insurance apply to construction mortgages?
Yes, but with conditions. CMHC's Progress Advance program allows insured construction financing with as little as 5% down when using an approved builder with a fixed-price contract. The property must be owner-occupied, and the total loan cannot exceed $1.5M (post-Dec 2024 reforms). Self-builds are generally not eligible for CMHC insurance during construction but can be insured at completion conversion.

### What are the key risks in construction financing?
Primary risks include: cost overruns (budget 10-15% contingency), construction delays affecting rate locks, builder insolvency (verify TARION/provincial warranty registration), and appraisal gaps between projected and actual completion value. Lenders mitigate these through holdbacks, inspection requirements, and builder qualification criteria.

### How does lot purchase financing work?
Vacant lot mortgages typically require 25-50% down with higher interest rates than residential mortgages. Terms are usually 1-3 years. Some lenders offer combined lot+construction packages where the lot purchase is the first draw. Municipal zoning confirmation and environmental assessments may be required before approval.

## Sources
- CMHC Progress Advance Program — https://assets.cmhc-schl.gc.ca/sf/project/cmhc/pdfs/factsheets/new/cmhc-quick-reference.pdf
- B-20 Construction Lending Standards — https://www.osfi-bsif.gc.ca/en/guidance/guidance-library/residential-mortgage-underwriting-practices-procedures-guideline-2017#2.5.4