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GUIDE_02 / 6 financing paths · Updated 2026-05-30

2026 ADU
Financing Guide.

Every realistic way to pay for a Puget Sound ADU in 2026 — HELOC, cash-out refi, construction-to-permanent, renovation loan, ADU-specific programs, and WSHFC. We don't sell loans; this is the spec sheet we walk every client through before they pick a lender.

OPTIONS_01 / Six financing paths

Compare every option

HELOC

Home Equity Line of Credit (HELOC)

Best for: Owners with significant equity and good credit who want flexibility

Loan amount
$50K–500K typical
Rate range
Prime + 0.5% to Prime + 2.5% (variable)
LTV
Up to 85–90% CLTV
Timeline
2–4 weeks to close
Pros
  • + Draw only what you need, when you need it
  • + Interest-only payments during the draw period (usually 10 years)
  • + No appraisal of the finished ADU required
  • + Fast to close — many lenders fund in 2 weeks
Tradeoffs
  • − Variable rate — payments rise if prime rises
  • − Requires substantial existing equity
  • − Some lenders cap second-lien CLTV at 80%
CASH-OUT-REFI

Cash-Out Refinance

Best for: Owners with a high-rate first mortgage who can refinance down

Loan amount
Up to 80% LTV of current home value
Rate range
Current 30-year fixed rates (typically 0.25–0.5% above purchase rates)
LTV
80% conventional, 80% jumbo
Timeline
30–45 days to close
Pros
  • + Fixed rate, predictable payments
  • + One mortgage payment, not two
  • + Tax-deductible interest (consult CPA)
Tradeoffs
  • − Resets your loan term — adds years of interest
  • − Closing costs of 2–5% of the new loan amount
  • − Doesn't make sense if current rate is below market
CONSTRUCTION-LOAN

Construction-to-Permanent Loan

Best for: Owners without existing equity, or building a high-value ADU

Loan amount
Based on as-completed appraisal (up to 80–85% LTV)
Rate range
Construction phase: Prime + 1–2% · Permanent: 30-yr fixed
LTV
80–85% of as-completed value
Timeline
45–60 days to close, 6–12 month build draw period
Pros
  • + Lends against the finished value, not current equity
  • + Interest-only during construction
  • + Converts to permanent mortgage automatically — one closing
Tradeoffs
  • − More documentation than HELOC (plans, GC contract, draw schedule)
  • − Lender controls draws — paperwork at each phase
  • − Higher closing costs than a HELOC
RENO-LOAN

Renovation Loan (FHA 203(k) / Fannie HomeStyle)

Best for: Buyers purchasing a home and adding an ADU in one transaction

Loan amount
Up to conforming or jumbo limits
Rate range
Standard 30-year mortgage rates + 0.125–0.5% margin
LTV
Up to 96.5% (FHA 203k) or 97% (HomeStyle)
Timeline
45–60 days, often tied to purchase closing
Pros
  • + Lower down payment (3.5% FHA / 3–5% HomeStyle)
  • + Single closing combines purchase + ADU build
  • + HomeStyle allows luxury items FHA does not
Tradeoffs
  • − FHA 203(k) requires HUD consultant and licensed GC
  • − Strict draw schedule and inspection requirements
  • − Mortgage insurance required at high LTV
ADU-PROGRAM

ADU-Specific Programs (e.g., RenoFi, Hometap)

Best for: Owners who don't qualify for conventional construction loans

Loan amount
$50K–500K typical
Rate range
HELOC-equivalent or equity-share structures
LTV
Up to 125% of current home value (RenoFi)
Timeline
3–6 weeks
Pros
  • + Lends against future (post-ADU) appraised value
  • + Equity-share options require no monthly payment
  • + Designed specifically for ADU construction
Tradeoffs
  • − Limited lender footprint — not all WA lenders participate
  • − Equity-share programs cost a share of future appreciation
  • − Rates and fees can be higher than conventional
WSHFC

WSHFC ADU / Housing Programs

Best for: Owners adding an ADU intended for long-term rental at affordable rates

Loan amount
Up to $250K (Home Advantage ADU pilot, varies)
Rate range
Below-market — typically 1–2% below conventional
LTV
Varies by program
Timeline
60–90 days, requires program qualification
Pros
  • + Below-market interest rates
  • + Some programs offer down payment / closing cost assistance
  • + Supports affordable housing goals
Tradeoffs
  • − Income and use restrictions (e.g., rent caps)
  • − Limited program availability — often pilot or capped
  • − Slower underwriting than private financing
TABLE_02 / Qualifying

What lenders actually want

FactorHELOCCash-Out RefiConstruction
Minimum credit score680+620+700+
Max DTI43–50%43–50%43–45%
Equity required20%+20%+Equity OR plans
Income verification2 yrs W-2 / 2 yrs 10992 yrs W-2 / 2 yrs 10992 yrs W-2 / 2 yrs 1099
Reserves needed2 months2 months6–12 months PITI
Appraisal typeDrive-by or fullFullAs-completed
GC contract required?NoNoYes — signed + draw schedule

Representative requirements as of 2026. Individual lender overlays vary — your loan officer is the source of truth.

FAQ_01

Frequently asked

What's the most common way Puget Sound owners finance an ADU?+

Among the homeowners we work with, HELOCs are the most common (about 55%), followed by construction loans (~25%), cash-out refis (~12%), and ADU-specific programs (~8%). HELOCs win on speed and flexibility when there's enough existing equity.

Can rental income from the ADU help me qualify?+

Yes — most lenders will use 75% of projected market rent (from an appraiser's rent schedule) toward your debt-to-income calculation, once the ADU is permitted and under construction. This often unlocks larger loan amounts.

Do I need a contractor selected before applying?+

For HELOCs and cash-out refis, no. For construction loans and renovation loans, yes — lenders require a signed contract with a licensed general contractor and an itemized draw schedule before funding.

How does the appraisal work for a not-yet-built ADU?+

Construction loans use an 'as-completed' appraisal based on architectural plans, comparable sales, and the local rental market. The appraiser values the property as if the ADU were already built, and the lender lends against that future value (typically 80%).

Are there grants for building an ADU in Washington?+

Not direct grants for private homeowners as of 2026, but WSHFC and a handful of King County pilot programs offer below-market loans tied to affordability covenants. Seattle's ADUniverse program offers free pre-approved plans, saving $5K–15K in design costs.

What about hard-money or private lenders?+

Available, but typically 9–13% rates with 6–12 month terms — only suitable as bridge financing for experienced investors building ADUs to refinance or sell.

AUTHORITY / Verify the spec

Programs & official guides

NAV_GRAPH / Local data

Continue researching

Need a draw schedule lenders will accept?

We provide free construction-loan-ready draw schedules, signed GC contracts, and itemized budgets for any Puget Sound ADU we bid — so your lender approves on the first pass.

Request a lender-ready bid →
FUND_2026 / MATCHED

HELOC, construction loan, cash-out refi — wrong order costs 1.5% APR. Get the sequence for YOUR equity.

Your equity, FICO, DTI and timeline dictate the loan stack. We'll map your numbers to the 3 lenders most likely to close — soft pull only.

  • Personalized loan stack from a real CFP-adjacent PM
  • 3 named lender intros, soft-pull only
  • Rate sheet sent before any call
Replies within 1 business day
WA Lic. GOLDNAB882L2Building since 2012
Direct line · Golden State ADU(206) 555-0192
LEAD_01 / FREE_CONSULT

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