Keeping mission-critical construction on track

Protecting the construction schedule from weather delays

Across the board, mission-critical builds can’t be commissioned or validated, and installations can’t start, until the building is weathertight. When wind, extreme cold, or rain holds up the envelope, everything queued behind it stops too.

Weather can be forecast, and its cost to a schedule can be priced. What’s often missing is a plan for keeping interior work going on the days the forecast is bad. Protecting the schedule from weather delays can allow critical interior activities to continue while permanent envelope work progresses.

What wind, cold, and rain stop on the jobsite

Wind stops lifting first. Crane limits come from the manufacturer and the lift plan, and cladding and work at height often stop at lower wind speeds than the crane does. On an exposed site, the crane serves every trade, so one wind stoppage hits several activities at once.

Cold slows concrete. Curing takes longer, and concrete that freezes before it has gained enough strength can be damaged. Mortar and stucco have the same problem. On one Nordic data center project, temporary weather protection was used to maintain workable conditions in temperatures of around -4°F (-20°C).

Heat causes trouble at the other extreme because it changes workability and curing. Rain stops concrete pours, sitework, painting, stucco work, and electrical installation. Standing water then slows equipment, deliveries, and crews long after the rain has stopped.

Why one lost day costs more than a day

A missed pour doesn’t stay a missed pour. It pushes back steel erection, interior buildout, commissioning, and turnover, and the trades behind it can’t start. The schedule loses the days the weather took, and it also loses the momentum built up to that point.

The investment takes a hit too. Missing the substantial completion date can trigger liquidated damages. Every extra week on site also carries general conditions costs. Equipment, site facilities, supervision, and project management keep costing money whether or not anyone is working. There’s a knock-on impact for the owner as well, because a late turnover delays the operations the building was built for.

Who pays for weather under AIA and ConsensusDocs contracts

Under the AIA A201 General Conditions, adverse weather can entitle the contractor to an extension of the contract time. The contractor has to document that conditions were abnormal for the period, couldn’t have been reasonably anticipated, and had an adverse effect on the scheduled work. The remedy is usually time, not money, so the contractor absorbs the cost of the longer schedule.

ConsensusDocs 200 takes a similar approach. Adverse weather that couldn’t reasonably have been anticipated is treated as a cause beyond the contractor’s control, which supports an equitable extension of time but generally not additional compensation. Many contracts, particularly in the public sector, go further and build a set number of anticipated weather days into the schedule, often based on historical NOAA data. Only weather beyond that baseline qualifies for an extension.

Most weather doesn’t reach these thresholds. Ordinary bad weather is the contractor’s risk under both forms, and even a time extension doesn’t recover what the delay costs. Check the language in your own contract before relying on this summary.

Where mission-critical schedules have no float

These projects work back from a date that won’t move. A data center has a go-live date, and commissioning and MEP installation wait for a protected building. Temporary screening can change that sequence. On one UK data center project, weatherproof screening allowed interior work to start earlier and helped cut six weeks from the schedule.

A semiconductor fab can’t start tool installation until the building is weathertight and clean. Similarly, a biopharmaceutical facility needs a controlled, contamination-free space before validation can begin. An automotive plant expansion has to fit inside a production shutdown, and the shutdown doesn’t wait for the cladding.

In each case, the open envelope is the constraint, and every activity that depends on it inherits the delay.

What temporary screening does to the sequence

Without temporary weather protection, interior work waits until the permanent envelope is substantially complete. Screening reverses that order.

Westgate Global’s engineered weather protection screen, Flexiscreen™, hangs from the building’s existing structural steel, so it needs no scaffolding or extra framing. Its V-overlap panel connection method provides an over 99% air- and dust-tight seal at any height and length, subject to survey.

With the open façades sealed, interior work and building systems installation can start while cladding continues on the other elevations. The same seal keeps dust out of areas that need to stay clean for tool installation or validation. For projects where dust contamination is as significant a schedule risk as weather, temporary screening can also form part of the site’s contamination-control strategy.

On an exposed elevation, Westgate Global calculates the wind load for that specific site and designs the screen to it.

What to settle before the schedule is locked in

Screening delivers the most value when it’s planned along with the schedule, and the least when it’s bought after the first two weeks are lost. Four decisions shape the design.

Start with the site. Coastal, elevated, and open sites take more weather, and the elevations facing the prevailing wind take the most. Then list the activities on or near the critical path that a wet or windy day would stop. Next, decide what the screen has to withstand: exposed elevations need a project-specific structural and wind-load design. Last, decide how the protection will move. A reusable, relocatable system can be moved between zones as the work progresses.

Westgate Global surveys, designs, engineers, installs, and signs off on the screening. Send us your drawings, schedule, and access dates, and our expert team can recommend the best solution for your project.

FAQs

At what wind speed does construction stop?

There’s no single speed. The crane manufacturer’s limits and the lift plan determine when lifting stops, and cladding and work at height have limits of their own. Check them for each activity on your site.

Can you pour concrete in cold weather?

Yes, with controls. The risk is concrete freezing before it has gained enough strength, so the specification and site conditions determine what protection the pour needs. An enclosure keeps wind and rain off the pour area, and the specification determines whether heating or insulation is also needed to maintain the internal temperature.

Does construction have to stop in winter?

No. Pours, stucco work, painting, and cladding need dry, calm windows, but interior work doesn’t once the envelope is sealed.

Is temporary weather screening only for large projects?

No. Westgate Global’s data center screening has been used on live projects for AWS, Intel, Meta, and Vantage Data Centers because those schedules have the least float. The same screening suits any project with weather-exposed work on the critical path.