Documenting Weather Delays So They Hold Up

Rain is not a delay. Rain that was worse than normal for that place and month, on a day when weather-sensitive critical work was scheduled, that actually stopped that work, is a delay. Everything about documenting weather comes back to proving each part of that sentence. This post covers what to build into the schedule before the weather arrives, what to record every day, and how to count the days at the end of the month with a worked example.

This is general practice, not legal advice. Contracts handle weather very differently: some grant time for unusually severe weather, some only above a stated baseline, some not at all. Read your weather clause and Division 01 requirements, and talk to counsel if a dispute is coming.

What usually has to be shown

Most weather provisions boil down to some version of these tests:

1. The weather was abnormal. It exceeded what a contractor should reasonably have anticipated for that location and time of year.
2. Work was actually affected. The weather stopped or significantly reduced work that was scheduled that day.
3. The affected work was critical. Losing that day pushed the completion date, rather than being absorbed by float.
4. Notice was given. Within the contract's notice window.

Miss any one and the request is weak. A month with twice the normal rainfall earns nothing if the crews were inside hanging drywall all month.

Before the weather: build it into the schedule

Anticipated weather days

Many specifications include a table of anticipated adverse weather days by month, the number of workdays the contractor is expected to lose to normal weather and must include in its plan. If yours does, those days have to be in the baseline. If it doesn't, the contractor typically derives an allowance from historical records, such as NOAA climate data for the nearest station, and states the basis in the baseline narrative.

The anticipated days are the contractor's risk. Only days beyond them are candidates for an extension.

Put them where the work is

There are two common ways to carry weather days in the schedule:

• A weather calendar. Weather-sensitive activities are assigned a calendar with the anticipated days marked as non-work days, spread across the month. The work simply doesn't get scheduled on them.
• Weather activities. Explicit "anticipated weather" activities placed in the logic ahead of weather-sensitive work during the months they apply.

Either way, don't hide weather inside activity durations, and don't dump it all in a single contingency bar at the end. Both make the later count almost impossible. More on setting this up: Calendars, Holidays, and Weather Days.

Code weather-sensitive activities

Tag activities that weather actually affects: earthwork, foundations, underground utilities, concrete placement outdoors, steel erection, roofing, exterior skin before dry-in, site paving and striping. Interior work after dry-in usually isn't weather-sensitive, though a building without permanent power and heat may make some of it so. Having the code means you can filter, at month end, to the weather-sensitive critical activities that were scheduled on each lost day.

Define what stops work

Agree up front, or at least decide internally, what thresholds stop each kind of work: a rainfall amount, wind speed for crane picks, temperature limits for concrete or roofing materials per the spec and manufacturer requirements. When a day gets called, you want to point to the threshold, not a feeling.

During the work: the daily record

The daily report is the primary evidence. Write it like someone will read it two years from now looking for holes, because someone might.

Record, every day:

• Weather observations at the site: precipitation, temperature high and low, wind, and the time the weather started and stopped.
• Ground or site conditions: standing water, mud, frozen subgrade, unsafe access.
• What work was scheduled for that day, by activity ID where possible.
• What work actually happened, and which crews were on site.
• What work was stopped, by whom, at what time, and why.
• Whether crews were sent home or reassigned to other work.

That last item matters. If the steel crew moved to unloading and shaking out iron in the yard, steel erection was still stopped, but the record should say what they did instead. Sending crews home at 9:00 because the wind was over the crane's limit is strong evidence. "Rain" in the weather box with no other notes is not.

Don't forget the day after

A two-inch rain on Tuesday may mean Wednesday and Thursday are lost too, because the subgrade is saturated or the excavation is full of water. Those days often count, but only if the daily reports show the site condition and why work couldn't proceed. Record pumping, drying, and re-compaction work, since it shows the effort to recover.

Get an independent source

Site observations are necessary but can be challenged. Back them up with records from a nearby official weather station and keep a copy of the data with the monthly file. If you use a site weather station, maintain it and note where it is.

At month end: count it

Here's a worked example for a site work and structure phase. Assume the spec's anticipated adverse weather table gives the numbers in the second column.

Walk through January. Weather stopped some work on 11 days. On 2 of those days, the only work affected had float (site fencing and a laydown area), so they're dropped. That leaves 9 days where weather stopped critical weather-sensitive work. Subtract the 6 anticipated days: 3 days requested.

February had 4 qualifying days against 5 anticipated, so nothing is requested. Whether February's unused anticipated day carries into March, or is simply lost, depends on the spec. Here we assume it does not carry, so March is 6 minus 5, or 1 day.

Total request across the three months: 4 days. Each with a daily report, an official weather record, and a list of the critical activities affected.

Check criticality against the update in effect

"Critical" means critical in the schedule update current at the time, not in the baseline, and not in hindsight. If foundations were critical in the January update, January's lost foundation days count. If an earlier slip made something else critical, the analysis should reflect that. This is the same principle behind period-by-period forensic analysis; see As-Planned, As-Built, and Windows: Forensic Schedule Analysis Methods.

Submit it the way the contract says

• Send notice within the contract's window, typically at the time of the event or within a set period after. A monthly batch of weather notices may or may not satisfy that; check. See Delay Notices: What to Include and When to Send Them.
• Submit the monthly weather tally with the schedule update if the spec calls for it, along with the supporting records.
• Once granted, add the days to the schedule as the contract directs: an adjusted contract completion date, a weather calendar change, or a time extension activity. Don't just let the finish slip and call it weather.

Weather is excusable but, under most contracts, not compensable, so the fight is usually over the count, not the money. For how those categories work, see Excusable, Compensable, and Concurrent Delay.

Checklist

• Put the anticipated weather days in the baseline, by month, where the weather-sensitive work is.
• Code weather-sensitive activities so they can be filtered.
• Write down the work-stopping thresholds for each kind of work.
• Daily reports: site weather, conditions, scheduled work, stopped work, crew actions, times.
• Record the recovery days after heavy weather and why work couldn't resume.
• Keep official weather station data alongside the site record.
• Count only days that stopped critical weather-sensitive work, then subtract the anticipated days.
• Send notice on time and submit the tally with the update.