Every figure below is the researched rule for Washington, with its citation and a direct link to the official source so you can confirm it yourself. Covers statutory interest and when it starts accruing, how Actual Cash Value is determined and whether labor can be depreciated, whether a “no damages for delay” clause is enforceable and how long you have to file, the state-specific inputs behind a fully burdened labor rate and who can be held liable for a construction-site injury.
The rate itself and the date interest starts running, which differs by claim type in most states.
12% / year (in practice, statutory floor usually controls)
Rate is the greater of 12%, or 4 points above the 26-week T-bill yield; the 12% floor is what applies in practice under current rate conditions. If the contract specifies its own rate, that governs instead.
From when the debt was incurred, but only if the amount is liquidated (calculable with exactness); otherwise only from judgment entry
Washington's leading case, Prier v. Refrigeration Engineering Co., holds that if damages are liquidated, meaning determinable with exactness from the contract or from recognized standards, without relying on opinion or discretion, prejudgment interest runs from the date they were incurred. If the claim is unliquidated, no prejudgment interest applies at all; interest starts only when judgment is formally entered.
Whether a given construction claim is 'liquidated' under this test is itself a legal judgment call; a Washington case applying the doctrine, State Dept. of Corrections v. Fluor Daniel, Inc., is at https://www.courtlistener.com/opinion/2599713/state-dept-of-corrections-v-fluor-daniel-inc/ if you want to read the reasoning further.
Same liquidated/unliquidated doctrine as contract claims: date of loss if liquidated, judgment-entry date if not
Washington doesn't use a separate date-of-loss rule for property damage; the same Prier liquidated/unliquidated distinction applies. If the property-damage amount is calculable with exactness (e.g., a fixed repair invoice), interest runs from the date of loss; if it requires discretion or opinion to fix the amount, interest only starts at judgment entry.
How ACV is determined, whether labor cost can be depreciated and the rules on releasing withheld recoverable depreciation.
Fair market value (not depreciation-formula, not broad-evidence)
Washington Supreme Court held ACV means fair market value, not strict replacement-cost-minus-depreciation.
Washington has a regulation expressly prohibiting depreciation of labor cost, with a narrow exception for labor embedded in the cost of manufactured materials.
WAC 284-20-010(4), adopted through rulemaking docket R 2021-04 and effective January 1, 2022, provides that except for the intrinsic labor costs included in the cost of manufactured materials or goods, the expense of labor necessary to repair, rebuild, or replace covered property is not a component of physical depreciation and therefore may not be depreciated or subjected to betterment when an insurer calculates actual cash value under a standard fire policy.
No Washington statute sets a general release deadline for recoverable depreciation, but a real 2022 regulation bars insurers from depreciating labor costs at all. The Insurance Commissioner has precedent for emergency extensions of policy-based repair deadlines.
Effective 1 January 2022, Wash. Admin. Code § 284-20-010(4) provides that the expense of labor necessary to repair, rebuild or replace covered property is not a component of physical depreciation and may not be subject to depreciation or betterment, apart from intrinsic labor costs already built into the cost of manufactured materials. No general statute sets a maximum holdback period, so the policy terms control that step. The Insurance Commissioner has previously used emergency authority to extend policy repair deadlines, for example during a pandemic construction shutdown in 2020. With no statute in play the policy is the whole of the law here, so read three things in it: what proof of completed repairs the insurer can require, how long the insured has to claim the withheld depreciation and whether that period can be extended in writing. Policy deadlines commonly run from 180 days to two years from the date of loss and they are enforced as written. Ask for the extension before the period runs rather than after.
Whether a no-damages-for-delay clause will be enforced against you and the deadline for bringing a construction contract claim.
Void by statute when the delay stems from the contractee's own acts or omissions
Washington voids any provision that waives, releases, or extinguishes a contractor's right to recover damages or an equitable adjustment for unreasonable delay caused by the acts or omissions of the contractee (or those acting for the contractee). Courts have applied this to let a contractor recover for the contractee's failure to exercise its own contractual rights to compel a third party's performance, or breach of its implied duty to cooperate; courts have also recognized that active interference by the contractee can fall outside what a no-damages clause was ever meant to cover.
RCW 4.24.360 covers both public and private construction contracts, unlike Oregon's narrower statute. Scoccolo Construction v. City of Renton confirms it reaches delays caused by third parties acting for the contractee, such as utilities under franchise agreements.
6 years for a written contract claim
Washington's general limitations period for an action on a written contract is 6 years from accrual, covering an ordinary construction-contract breach or payment dispute. Two deadlines sit in front of that one on most construction claims. A mechanic's lien and a payment bond claim each run on their own, far shorter clock, counted from last furnishing rather than from breach and missing either one removes the security while leaving the contract claim alive but unsecured. Check those dates first. Accrual is the other half of the question: the period runs from breach, which on a payment dispute is usually the date payment came due rather than the date the work was done.
A separate six-year statute of repose, RCW 4.16.310, runs from substantial completion regardless of when a defect is discovered. Check which one governs your claim.
The state-specific rates and requirements that sit underneath a fully burdened hourly labor cost.
Washington's 2026 qualified-employer tax rates range from about 0.27 percent to 6.03 percent (including the Employment Administration Fund add-on) and the taxable wage base is $78,200.
Washington's Employment Security Department uses an experience-rated system with 40 rate classes. The 2026 combined rate for qualified employers, meaning the experience rate plus the graduated social cost plus the Employment Administration Fund, runs from about 0.27% to 6.03%. Delinquent and deferred-payment employers face additional surcharges. The 2026 taxable wage base is $78,200 per employee, rising to $82,000 in 2027. New employers are assigned an average industry rate for their first several years before moving to full experience rating.
The $78,200 wage base is the highest in the country by a wide margin, so Washington payroll costs turn on it more than on the rate. Look up the industry rate rather than expecting a single new-employer figure.
Washington is a monopolistic workers' compensation state. Most private employers must buy coverage through the Washington State Fund administered by the Department of Labor & Industries (L&I); there is no private insurance option, though qualifying large employers may self-insure.
Washington is one of the small number of monopolistic states for workers' compensation. Nearly all employers must obtain coverage through the state fund administered by the Washington State Department of Labor & Industries (L&I), rather than from a private insurance carrier. Large employers meeting certain financial and safety criteria may qualify to self-insure directly, subject to L&I approval, but the open private-carrier market that exists in NCCI states is not available in Washington.
Washington's own L&I insurance overview page did not explicitly state the monopolistic designation in the content reviewed; that characterization is well established through independent industry sources (e.g., insurer guides to monopolistic states) and should be treated as reliable, but a direct statement from lni.wa.gov was not captured verbatim.
Washington requires prevailing wages on essentially all public works and maintenance contracts under RCW 39.12, with no general statewide minimum dollar threshold; a separate rule sets a $25,000 threshold specifically for state college and university construction.
Washington's prevailing wage law (RCW 39.12) requires state and local government contractors and subcontractors to pay prevailing wages on public works and maintenance contracts. The general statute does not specify a minimum contract-value threshold. A separate provision applicable only to state college and university construction sets a $25,000 threshold amount, per the U.S. Department of Labor's summary of state prevailing wage laws.
OSHA enforcement structure, how much weight an OSHA violation carries in a negligence case and whether an injured worker's own employer can be pulled back in.
Pure comparative fault, no bar; recovery reduced by the worker's share of fault
Recovery is reduced in proportion to the worker's share of fault, with no threshold that cuts it off. A worker 90% at fault still recovers 10% of the damages.
Washington is a pure comparative state by statute. The worker's share reduces the award and never defeats it.
The section abolishes last clear chance in terms. RCW 4.22.005 applies 'whether or not under prior law the claimant's contributory fault constituted a defense or was disregarded under applicable legal doctrines, such as last clear chance'. In the five contributory jurisdictions that doctrine is one of the few exits from a total bar; here it is simply gone, because there is no bar to escape.
One point matters a great deal on a construction claim and it is not in this section. RCW 4.22.070 governs how liability is shared among defendants and Washington's scheme turns on whether the claimant is at fault at all: a fault-free claimant is in a different position from one carrying even a small share. The detail of that section has not been read here and a figure produced by this calculator does not account for it. Where a worker carries any fault, what is collectible from each defendant is a separate question from what the claim is worth.
No general cap on non-economic damages
Most states cap non-economic damages only in medical malpractice actions, which does not reach a third-party construction claim. Economic losses, medical bills, lost wages, future earning capacity, are not capped by these statutes.
WISHA: full state plan, private + public sector
Washington operates WISHA (Washington Industrial Safety and Health Act), a full OSHA-approved state plan administered by the Department of Labor & Industries (L&I) / Division of Occupational Safety and Health (DOSH), covering both private and public-sector employers. A state plan must be at least as effective as federal OSHA and may set stricter standards, so check the state rule before assuming the federal text applies. It also covers state and local government employees, which federal OSHA does not, so a public works injury is inside the state agency's jurisdiction. Citations are issued by the state agency and contested before the state's own review body rather than the federal commission, which changes where the file lives when you go looking for it. Reporting deadlines follow the federal rule: a work-related fatality within 8 hours, an inpatient hospitalisation, amputation or loss of an eye within 24 hours. For a construction claim the inspection file matters more than the citation: photographs, measurements, witness statements and the inspector's narrative are usually obtainable and are often the best contemporaneous record of the site.
Washington places the duty to comply with WISHA safety rules on the general contractor as a matter of law, the strongest treatment of any state here
Stute v. P.B.M.C. held that a general contractor has a duty to comply with WISHA safety regulations for the benefit of every worker on the jobsite, not just its own employees. The court treated the general contractor's supervisory authority as per se control over the workplace, so the duty arises as a matter of law rather than turning on how much control the contractor actually exercised. The injured worker still has to show the violation and that it caused the injury. Kelley v. Howard S. Wright Construction is the foundational retained control case behind the line and the standard has since been extended to upper-tier subcontractors and to owners who retain control of the worksite.
In practical effect this puts Washington closer to New York's Labor Law than to the majority evidence-only rule.
Statutory employer status is a live issue in Washington, with Hymas v. UAP Distribution the case on point.
Third-party actions may otherwise proceed against owners, contractors, manufacturers and motorists through premises possession, retained control, safety undertakings, statutory duties or product defects. The bigger point on a Washington site is the general contractor's non-delegable WISHA duty; see the OSHA entry below.
Industrial insurance under Title 51 bars employer negligence claims, with a narrow deliberate intention exception
Wash. Rev. Code tit. 51 bars negligence claims against the employer through industrial insurance. Washington recognises a narrow deliberate intention exception. Confirm its current scope directly before relying on it. In practice exclusivity takes the direct employer off the tort table entirely, whatever the OSHA file shows. The claim runs against the other parties on the site: the general contractor, the owner, another subcontractor, an equipment manufacturer. The employer or its carrier then asserts a lien against whatever the worker recovers from those parties, so the figure the worker actually keeps is the recovery less the lien, the fee and the costs. Whether the lien is reduced for the cost of obtaining the recovery is a separate state question worth asking early, because it moves the net more than most people expect.
Stute doctrine: the GC's duty to comply with WISHA safety rules runs to every worker on the site as a matter of law, not just its own employees
Under Stute v. P.B.M.C. (1990) and Goucher v. J.R. Simplot (1985), the Washington Supreme Court held that a general contractor's specific duty to comply with WISHA safety regulations runs to any worker on the jobsite who may be harmed by a violation, regardless of whether an employer-employee relationship exists between that worker and the GC. In practice, a GC can be held directly liable to a different subcontractor's injured employee for a WISHA violation the GC didn't directly cause. A jobsite owner (as opposed to a GC) is not per se liable this way; an owner's WISHA duty depends on whether the owner retained control over how contractors performed the work.
ClaimDuke's calculators compute delay and extended overhead (Eichleay), fully burdened labor rates, ACV/RCV property loss, claim interest and construction-injury settlement ranges. Every calculation is free and live; a documented, citation-backed report is $19.
This page is reference information for your own verification. It is not legal advice and is not a substitute for confirming the current rule with the official source linked above or with counsel. Several states' interest rates float and reset on a schedule (monthly, quarterly or annually), so always check the live source for the figure as of today rather than relying on what is shown here. Which rule actually applies to your specific claim is itself a legal question this page cannot answer for you.
