AIA A201 §8.3 Weather Delays, Explained

AIA A201 is the most widely used general-conditions document in US construction, and its weather language is short enough to read in a minute — and vague enough to argue about for months. Here is what it means in practice.

What the clause actually says

§8.3.1 allows the Contract Time to be extended when the contractor is delayed by causes beyond their control — the list includes "adverse weather conditions documented in accordance with Section 15.1.6.2." That cross-reference is the whole ballgame, because 15.1.6.2 is where the burden lands on you.

§15.1.6.2 requires that a claim for adverse weather be documented by data substantiating that the weather conditions were abnormal for the period of time, could not have been reasonably anticipated, and had an adverse effect on the scheduled construction.

Test 1: "Abnormal for the period of time"

A201 never defines abnormal, and that silence is where claims die. Since the standard is comparative, you need a reference point: what is normal for this ZIP code in this month? The industry convention is a 10-year historical average of daily precipitation from the nearest official station. The same gap exists in every other standard form — see unusually severe weather: what actually counts for how the FAR and ConsensusDocs phrase the identical test, and where the line gets drawn in practice.

If April normally sees 8 rain days at your site and you got 9, you have no claim — even if all 9 hurt. If you got 17, you have the beginnings of one. The exhibit that establishes this is worth more submitted with your bid than produced during a fight; see calculating anticipated weather days.

Test 2: "Could not have been reasonably anticipated"

This is why the baseline cuts both ways. By signing, you implicitly accepted normal weather for that season and region. Bidding a Seattle site in November means you anticipated rain. The only weather you did not anticipate is the portion above the historical norm — which is, again, exactly what the baseline quantifies.

Test 3: "Adverse effect on the scheduled construction"

The weather must have hit work that was actually scheduled, and the delay must show up in the critical path. Two consequences most subs miss:

• Non-critical work does not count. If the rained-out activity had float, the project did not get longer, and A201 gives you nothing.
• Drying days count if you can prove them. Nothing in §8.3 says the impact must be rainfall itself. If saturated ground made the site untrafficable on Thursday, Thursday is claimable — but only with soil evidence, not adjectives.

Time, not money

The single most misunderstood point: §8.3 extends time; it does not open the checkbook. Weather is the classic excusable but non-compensable delay. You get relief from liquidated damages. You do not get your idle crew and equipment costs — unless your specific contract says so, or the delay is compounded by something the owner did.

The 21-day rule

§15.1.3 requires notice within 21 days after occurrence of the event, or after you first recognize the condition — whichever is later. This is the deadline that quietly kills more valid claims than any evidentiary problem. Send notice early with partial information; you can supplement the analysis later.

Check the supplementary conditions first

Base A201 language is regularly modified. Common variants worth hunting for before you rely on anything above:

• Fixed anticipated rain days — e.g. "Contractor shall include 3 weather days per month." Then the baseline is contractual, not historical, and only days beyond it are claimable.
• A named weather station that must be used for all measurements.
• A defined threshold — e.g. "a weather day is any day with precipitation exceeding 0.10 inches during which work is suspended for 4+ hours."
• No-damage-for-delay clauses that foreclose compensation entirely.

Ilystics provides weather and soil analysis, not legal advice. Section references are to AIA Document A201-2017 and are provided for general orientation only — your contract, its supplementary conditions, and your jurisdiction control. Consult your attorney or claims consultant on entitlement.