The weather forecast

Michael Mayock takes a look at how the weather impacts the construction industry

Working outdoors has many perks, including an improved mood and boosted energy, as well as working in the fresh air being known to help boost the immune system. However, in the construction industry, working outside comes with its fair share of health and safety and project management issues, causing delays to timelines, running over on budgets, damage to sites and plants, and, if not managed correctly, injuries. All of these problems can be amplified by poor and extreme weather conditions, something that, according to research, accounts for 21 per cent of delays on a construction project.

We explore the impact of the weather on construction workers and sites and see how even a little rain can wreak havoc on project timelines.

Hot isn’t ideal
On paper, a hot and sunny forecast sounds like perfect outdoor working conditions, but in reality, this type of weather can cause a whole host of problems.

With temperatures recently reaching record-breaking highs in the UK, it’s more important than ever to ensure that all operatives working on a site, or anyone working outside for that matter, are properly hydrated, take regular breaks from the sun and the heat, and wear the correct PPE to protect them from harsh climates. If it gets too hot, it may be time to down tools and call it a day.

Unlike the cold, heat makes materials expand and this can affect the dimensions and placement of particular materials. Concrete can experience thermal shock and become dry, weak and crack whereas materials such as steel can expand when exposed to high temperatures. In these conditions, it’s not unlikely for suppliers to stamp ticket the concrete in case it dries up to quickly.

The dangers of dust
Hot and dry weather conditions also produce a lot dust. Whilst dusts on a construction site is unavoidable and inevitable, (we’ve written an article on the dangers of silica dust), sometimes, the presence of dust can be amplified by a very hot environment.

Airborne dust and dirt not only causes dangers to the workers who are ingesting it, but it can also be damaging to some machines and equipment by clogging up filters and impacting their effectiveness and efficiency.

Dust can be reduced by using a dust suppression system; these bowsers help to saturate and eliminate dust in the air, and are a worthy investment to avoid the complications that too much dust can cause to a construction site.

Here comes the rain
Rain causes countless problems to those working on a construction site. Working outside in the rain is not pleasant and any type of rain can make work more difficult, but incessant rainfall can create long delays to a project timeline. Heavy downpour can bog construction sites and make surfaces slippery, not to mention extremely muddy. These overly muddy conditions then require extra road cleaning and wheel washers – adding to the overall budget and delaying planned work.

To mitigate the amount of mud created from muckaway, it’s important to bund and seal any muckaway piles to prevent the rain from penetrating, therefore keeping the muck dry and also prevent the muck pile from collapsing.

If torrential rain has filled trenches with water, then time will have to be invested in pumping the water out, but if the edges of the trench have been bunded and sealed, it will be quicker and easier to fix overall thanks to forward-thinking damage control.

Further to this, there are many materials that should not be exposed to too much moisture. Take bricks for example, moisture present in bricks while building can result in condensation collecting, and if these bricks absorb too much water, damage to the structure of the brick can be caused.

If certain materials are exposed to the rain for too long, they can be subjected to rust and corrosion. This is another reason why regular plant inspection is important, else your machines could break down when damage could have otherwise been prevented.

If there’s a storm with the rain, it can present its own set of problems; not only is there the wet weather to contend with, but also storms usually bring high winds creating even more setbacks and difficult working conditions.

High winds also cause a lot of disruption with lifting-machinery or equipment, making it difficult to operate safely and smoothly. If high or gale-force winds are predicted, it’s best to avoid these types of machines or cranes. Winds can also spread dust, and as mentioned above, dust causes a plethora of environmental health issues to sites and its workers.

Low temperatures
Working outside does have its perks, but when temperatures drop, it can become uncomfortable working in the cold conditions. Though, chilly temperatures impact more on a construction site than just cold workers.

In a similar vein to heat making materials expand, cold can make them contract making a run-of-the-mill task become arduous.

Concrete is particularly difficult to set in cold temperatures, with the knock on effect being a slow down in laying foundations, slabs and brickwork, impacting the overall project timeline and, importantly, drastically reduces the concrete’s stability and strength.

As with extremely hot conditions, suppliers sometimes stamp concrete and tarmac to state that the material was fit-for-purpose upon leaving their hands, which essentially means that they are happy to supply to material but cannot guarantee that when we come to use it, the structure (and therefore strength) may not be the same after being exposed to particular elements.

This is an important precaution to take though, because concrete emits heat and moisture more quickly in lower temperatures. It is industry-recommended to keep concrete above ten degrees Celsius for it to maintain its strength and curing. Whilst it can be laid at a lower temperature, it will take longer for the concrete the set and this could have a detrimental effect on the overall project timelines. In extremely cold conditions (though rare in the UK), concrete can freeze – this can mean that the concrete loses around 50 per cent of its potential strength.

Low temperatures can also produce ice and frost, and when this happens, there’s a dual-impact of expansion and contraction, whereby the ground – or road formations – can expand when frozen (where it’s essentially holding all the water) and the when it eventually thaws and releases the water, the material can sink. It’s far more difficult to prepare a road in these conditions and, unless the tarmac has already been delivered, it’s probably best to hold off until you’re confident that the formation and sub-base is to the correct standards, with no chance of collapsing/sinking.

As well as impacting the machinery, it’s also more dangerous for our plant operators to be driving in icy and foggy conditions and so they will need to drive at an even slower pace, or opt for tasks that are not reliant on driving plant.

How to prepare
Sometimes, it’s not possible to predict what the weather will be. In the UK – looking at summer 2019 with it’s record-breaking heat wave and record-breaking rainfall, in the same month – the summer weather is as unpredictable as winter. But, construction companies should be mitigating risk as much as possible. Whilst it’s not possible to know the weather conditions when you price up a job, regularly checking the forecast, planning your tasks on a weekly basis and taking precautions around this is a good way to stay on track.

On-site safety measures can be having a thorough health and safety plan in place; ensuring surfaces are not prone to being slippery when wet, using the bund and seal method around your muckaway and trenches, have water pumps at the ready and use dust suppression bowsers to eliminate harmful dust.

If possible, before your project starts, add a contingency plan into your overall project timings. Best case, you won’t need it and you could then, in theory, finish ahead of schedule. Always work to industry best practice; it’s better in the long run, to protect your site and staff.

Finally, it’s important to keep an open communication with your clients if you think that bad weather could impact the site’s progress.

Michael Mayock is Managing Director of Mackoy. Founded in 2011, Mackoy is the fastest-growing groundworks and civil engineering company in the south. Based in Hampshire, but also covering Dorset, Berkshire, Surrey and Sussex, Mackoy is breaking new ground and helping to create communities with high-quality servicesand state-of-the-art machinery.
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