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Can we avoid project delays caused by bad weather?

Has your project been delayed by bad weather?

Contractors are an eternally optimistic bunch and never seem to allow for any weather related impacts on construction projects. What, - are you really going to work on a twelve month long project and think you won’t encounter rain, winds, summer, and winter at some stage in the course of your project! If you have 500mm (20 inches) of rain in 3 months it will almost certainly disrupt your project. But, if the average for that region is 500mm for those 3 months we shouldn’t be surprised and we should have made allowance for rain disruptions in our schedule and taken mitigating measures to reduce the impact of the rain on our schedule.

Contractors often put the blame on clients for their unreasonable schedules and say it’s impossible to allow additional time for delays caused by rain – rain which is average and will almost certainly occur! Well that’s professional suicide if you knowingly accept a schedule which doesn’t allow for weather conditions which we can expect in that region during the time of construction – weather which will almost certainly occur. Instead of knowingly risking your project and betting against weather events not occurring, even though they happen on average, you might consider taking on the odds at your local casino.

But some contractors do make their life even harder.

Is it possible to at least avoid some of these weather delays?

How does inclement weather impact our construction projects?

Many only see weather disruptions as the direct time lost during the bad weather. Unfortunately some events can cause damage to partly completed structures which could take days or weeks to repair. Recovering from one hour of rain could take days while we pump work areas dry, clean debris and wait for materials to dry out. Adequate insurance can cover us for some of the damages but they usually don’t cover for the delays caused to the project.

1. Rain – I’m sure we have all experienced rain on our projects. Rain:

a. Stops work due to discomfort as well as safety issues.

b. Causes damage. Excavations collapse, building finishes open to the elements are damaged, silt and debris have to be cleared.

c. Saturates materials which particularly with earth moving jobs result in us having to wait for the materials to dry out before we continue.

d. Might cause materials could also become contaminated and mixed together.

e. Could make roads impassable and equipment can become bogged down.

f. Often floods work areas, causing delays while the areas are pumped dry.

g. May well cause river courses to flood sufficiently to sweep equipment and structures away.

2. Wind:

a. Prevents us from lifting materials with cranes and can even cause accidents by overbalancing cranes.

b. Can cause physical damage by blowing down partly completed work or stacked construction materials.

c. Might cause dust which could stop some operations

3. Extreme temperatures could cause work to stop, or certainly negatively impact productivity. Ice may damage water pipes and equipment. Extreme temperatures can be dangerous and hyperthermia and heat stroke can kill.

4. Lightening can result in the project being temporarily shut down and a direct lightning strike on an item of equipment could cause damage which is costly to repair and delays the project. Lightening may also start fires and partly completed structures could be burned down.

5. Severe storms such as hurricanes and cyclones not only cause damage to the project site, they stop work during the event and usually stop the project several days before the storm strikes so the project can be made storm ready.

Can we mitigate some of the weather delays?

There are a number of measures contractors can take to at least mitigate some of the delays caused by bad weather.

1. During the bid or tender stage. Understand the expected weather conditions at the project location. More importantly understand the contract documents – know what they say about the risks of inclement weather and in particular unseasonal and severe weather conditions. In some circumstance you may decide to exclude weather conditions which are worse than the norm from your bid price. Allow for the costs and delays of the normal weather patterns. Discuss some of the issues relating to the weather with your client. For instance it’s often folly to start a project at the height of the wet season in the tropics. Hopefully informed clients will understand this.

2. Preparing the construction schedule.

a. Schedule activities that can be impacted by rain, such as earthworks, to occur outside of the rainy season.

b. Close up buildings ahead of the rain season or cold weather.

c. Schedule activities such as roofing and lifting large loads to happen outside the windy season.

d. Understand the expected weather conditions and allow additional time in the schedule to compensate for delays caused by inclement weather.

3. Consider alternative construction methodologies. This might even mean redesigning structures. We can manufacture parts of the structure in modules or precast some sections reducing the work that has to be done in poor weather. Consider different foundation solutions to minimise excavations which have to be done in the rainy season.

4. Modify your construction working times. To avoid the summer heat you could start working earlier in the day to make the best use of cooler temperatures and then stop earlier in the hot afternoons. Often strong winds occur in the afternoons, or windy days calm down in the late afternoon so it may be possible to schedule lifting operations to times of the day when there’s less chance of winds impacting operations – even if that means the lifting takes place after normal working hours. Maximise good weather opportunities which might even mean working additional shifts on weekends (these usually cost more but progress on the project may justify these extra costs).

5. Put protection measures in place. A simple earth berm around excavations can protect excavations from flooding. Modest open-cut storm drains can channel rain water away from work areas. Avoid low lying areas on the work site which can become flooded – especially ensure that material storage places are adequately drained and can be accessed even in wet weather. Have adequate plastic sheeting to cover recently completed work that can be damaged by rain. Put measures in place to protect new concrete from extreme cold. These measures often don’t cost much but they can save valuable time after a rain storm.

6. Reschedule tasks in anticipation of bad weather. This could include delaying major concrete pours or postponing heavy lifts. In some areas regular afternoon thunderstorms occur so you want to ensure that major tasks are completed ahead of these storms, so starting earlier or working in smaller sections may help.

7. Prepare your project before severe weather strikes. Ensure your project team has sufficient warning that a storm or rain is on its way. Loose materials must be secured, protective covers rigged to protect unfinished work from possible damage, and checks done to ensure storm-water drains are clear, and partly completed structures are properly braced.

8. Ensure your teams are able to work safely in inclement weather. No-one wants to work in the rain, freezing temperatures or searing heat. However we often have to so it’s important your team has the required equipment. This could include adequate rain gear, waterproof foot-wear, warm clothing, warm rest shelters, adequate water, safe working conditions, etc. Saving on some of these items may mean the project loses time because employees aren’t adequately equipped to work in the conditions.

9. Make certain temporary roads and working platforms are adequate so that rain water drains away, and equipment and vehicles can operate without becoming bogged or dangerously skidding. We all try to save money on our project roads and then invariably lose production when we cannot access our work areas after rain.

10. Have adequate water pumps on site and have a system in place to dispose of storm water. We need to ensure we get our work areas clear and safe for work as quickly as possible after the storm ends. Inadequate preparation and saving a few thousand dollars could cost the project a day or more of lost production. If you know it’s going to rain at some time during the project be prepared for when it does.

We should also consider the weather risks to activities happening off-site. Items being manufactured off-site may be hampered by poor weather. Will your supplier be able to continue manufacturing if they experience poor weather? I’ve often suffered delays because suppliers couldn’t paint the items because of wet weather. Choosing an alternate supplier that has covered manufacturing facilities may be more expensive but could avoid the risk of poor weather impacting delivery.

Understand the transport networks and how poor weather can disrupt these. Sometimes it pays to keep sufficient stock or get materials in earlier to avoid disruption caused by heavy rains. We have had projects cut-off from major centres for days.


We can almost guarantee that most projects will be impacted by inclement weather. In most cases this shouldn’t be an excuse for delays, although unfortunately these days more projects seem to be interrupted by extreme weather events which couldn’t have been foreseen. We can prevent, or at least mitigate many of the delays by understanding the weather patterns in the area and allowing for these expected weather disruptions in our schedule.

Proper planning can also mean that weather dependent activities are scheduled for times when better weather can be expected. We can also implement mitigating measures to reduce the damage and return the project to full production as quickly as possible.

Contractors shouldn’t be expected to shoulder the responsibility of extreme weather events or those that couldn’t have been reasonably expected. They should therefore be cautious in accepting contracts where they could be liable for these delays.

How has inclement weather impacted your project?

Are weather disruptions a major cause of delays for your projects?

(Paul Netscher is the author of the books 'Successful Construction Project Management: The Practical Guide' and 'Construction Claims: A Short Guide for Contractors', and 'Building a Succesful Construction Company: The Practical Guide' all available from Amazon and other on-line book stores in paperback or Ebook. Visit to read more) 

Image courtesy of Stuart Miles at

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