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Lien Lawaka: materialman's lienaka: contractor's lienaka: construction lien

Mechanic's Lien

In Plain English

A legal claim filed against a property by someone who did work or supplied materials but wasn't paid.

Definition

A mechanic's lien is a statutory security interest in real property that can be claimed by contractors, subcontractors, material suppliers, and other parties who have contributed labor or materials to improve the property but have not been paid. The lien attaches to the property itself, not just to the owner personally, and can be enforced through foreclosure proceedings. Each state has its own mechanic's lien statute with specific notice requirements, filing deadlines, and enforcement procedures.

Why It Matters in Bidding

Lien rights are the leverage that gets contractors and suppliers paid, so estimators and PMs build preliminary notice and waiver tracking into bid assumptions and cash-flow planning. Missing a statutory notice or filing deadline can wipe out collection security entirely, while an unexpected lien down the chain can cloud title, stall draws, and trigger owner backcharges.

Example

After the GC went 90 days past due on a $120,000 progress payment, the drywall sub filed a mechanic's lien against the owner's property to secure its claim while pursuing collection.

Related Terms

LienLien WaiverPreliminary Notice

Frequently Asked Questions

Generally anyone furnishing labor, materials, or equipment that improves the property, including GCs, subs, sub-subs, material suppliers, and sometimes design professionals or equipment lessors. Many states limit rights for parties too far down the contracting chain, and unlicensed contractors may forfeit lien rights entirely in licensing states.
A preliminary notice tells the owner and lender that a party is furnishing labor or materials and may later claim a lien. Many states require it within a set window after first furnishing, often 20 days, as a precondition to lien validity. Failing to serve it on time can void otherwise legitimate lien rights.
Signing a lien waiver releases lien rights for the work or amount described, so unconditional waivers should never be exchanged before funds actually clear. Use conditional waivers against pending payments and confirm the dollar amount, through-date, and excluded retainage match your records before signing anything.

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