Innovative eco-social housing neighbourhood reaches completion in Wales

A version of this article was published on The Fifth Estate on 17 May.

Glen Peters standing outside one of the two-bedroomed semi-detached houses.

The first tenants have moved into Pentre Solar, an eco-social housing neighbourhood being constructed in Glanrhyd, Wales. ('Pentre' means village in Welsh.)


Dr Glen Peters, chief executive of Western Solar, has an ambition for his company to supply 1000 homes and to work with housing associations and local authorities to provide social housing.

The South-facing front of a three bedroomed house with plenty of glazing to capture the sun's heat. Inside it falls onto a black, melamine-covered concrete floor to absorb the heat.

The North-facing rear of a three bedroomed house. The homes are clad in local larch. This is projected to last at least 25 years before it needs replacing. Much care in the detailing of the design should extend the cladding life well beyond this point.

Peters estimates the build cost is about £120 per square foot (AU$19 a square metre). This has led him to set a rental cost of the two-bedroom houses of £480 a month (AU$836), a level in line with the local 106 planning condition of no more than 80 per cent of local market rents. The three-bedroom houses are set at £620 a month (AU$1080). For the developer, this gives a 3.5-4 per cent return on investment.

A pair of two-bedroomed semi-detached houses. All the homes have solar roofs.

Local materials and labour

Costs have been kept low and as much as possible of the houses manufactured locally from local materials. In total 80 per cent of the building is manufactured locally out of local timber and 40 per cent – the airtight frames – are manufactured in a nearby factory – a converted cowshed – to be assembled on site.

Peters says the multiplier effect of the benefit to the local community for every £1000 invested is £2200, a factor of 2.2.

The timber frames are kept out of direct contact with the ground to prevent damp from rising:

A footing protected from damp on the patio.

The homes’ design builds upon the developer’s experience of a prototype house, Ty Solar:

The prototype Ty Solar (Ty is Welsh for House so the name means Solar House in English) in West Wales. In the background can be seen the first solar farm in Wales which finance the building of Ty Solar.

Ty Solar was constructed in 2010 using the profit from Peters’ solar farm, the first in Wales. It cost about £75,000 (AU$130,640) to build with a £47,000 (AU$81,870) grant from the Sustainable Development Fund.

The unit costs of the Glanrhyd houses, built on the site of a now-demolished garage, were higher than normal, mainly because of the land reclamation, provision of services and unusual weather-related costs, as well as complying with planning conditions in an area of outstanding natural beauty.

The three-bedroom homes occupy 100 square metres, the two-bed ones slightly less, but still feel spacious.

The company is focused on providing social housing as Peters believes there is a reasonable business in creating good quality affordable housing, as none of the large developers seem to interested in doing so.

While it is economic and technically feasible to build these homes, politically Peters’ route has not been easy.

”Politicians have been unduly influenced by volume building companies, and while they love the houses it has been difficult to persuade local authorities and housing associations of the benefit of backing this design, despite the fact that occupants have virtually zero energy bills. The key performance indicators imposed on housing associations are unduly skewed towards capital costs rather than tenant and community welfare,” he says.

He is hoping that when he has occupancy data to back up his case, more housing associations and councils will be interested in the model.

Zero energy bills

The timber frame houses are built according to passive house principles, though are not validated as such due the cost of doing so, versus the benefits.

Each monopitch roof sports 8kW of integrated photovoltaic panels. Over a year these generate surplus energy, providing an income from a feed-in tariff, as well as giving the occupants free electricity. Total energy demand is about 12 per cent of a conventionally built home. Beneath the solar panels is a galvanised steel sheet that laps over the timber frame.

They sit on a concrete slab, unlike the prototype, which was constructed using the box beam method with a suspended timber floor. Peters says concrete is more durable, with more thermal mass and has a lower maintenance requirement, although with a greater carbon footprint.

The windows are double, not triple-glazed, to keep costs low as Peters believes that the incremental benefit of the extra pane of glazing is cancelled by the cost in the mild local climate.

The insulation is all 27cm of recycled newsprint pumped into the cavity. This type of eco-insulation is in general the most economic and ecological. The paint is clay-based – breathable and with no off-gassing. Although more expensive per litre, it requires fewer coats on bare plaster.

The houses all come fitted out with the most efficient washing machine, condenser drier, kitchen, water-saving bathroom with occupancy sensors in areas such as toilets, internet connection, Wi-Fi and an outside socket for charging an electric vehicle. There are LED lights throughout.

All of these relatively spacious homes are provided with the most energy-efficient appliances and exceptional attention to detail.

Communal electric car

The Nissan Leaf charging outside one of the houses.

The occupants of the estate have been given a Nissan Leaf to use collectively, charged by the solar panels on the roofs.

“It’s a way of getting neighbours to cooperate with each other and eliminate the need for a second car,” Peters says.

Energy storage

The South-facing homes are generous in their space, their form determined by the maximum depth allowed by the passive heating.

The rest of the heating is provided in a surprising manner, using the best of old technology with new: solar electricity and storage heaters.

An installed storage heater; proven, old technology meeting the new.

Storage heaters contain thermally massive blocks that are heated up by an element. They then release that heat gradually over many subsequent hours.

This form of energy storage was introduced to British homes in the 1960s and ’70s on a special tariff called Economy 7. Since nuclear power stations could not be switched off, unlike other forms of electricity generation, these tariffs allowed people to use nuclear electricity at night – at a lower rate when national demand was low – to charge the storage heaters.

The problem was that by the time the heat was needed, the following evening, they were often too cool and many people subsequently removed them and installed central heating instead.

Here, the idea is to let the storage heaters be heated up during the day by the solar panels on the roof, meaning they are able to provide adequate heating through the evening and night provided that there has been average sunshine (50 per cent of a June summer’s day) during the day.

This may not be the case in the depths of winter and so the homes are also grid-connected. They export surplus energy when there is some – after the electric car and storage heaters have been topped up – and purchase it when not enough has been generated.

“Storage heaters are incredibly cheap,” Peters says, “and a well proven technology. Whereas the storage we had to start with in the prototype house – lithium-ion batteries – were designated a fire risk and we had them taken out. They are also much more expensive.”

A pair of two-bedroomed semi-detached passive solar houses.

The prototype house has been monitored and has well exceeded the predicted generation capacity, providing twice the electricity used over the year.

Peters says: “We have spent £2 million (AU$3.5m) researching and developing a sustainable timber building system that is 100 per cent British, powered by solar energy. We hope now to create 1000 homes across Wales and the UK, once the current political uncertainty is out of the way and we have won the argument on the efficacy of timber housing.”

David Thorpe is the author of a number of books on energy efficiency, sustainable building and renewable energy, including:

• The Expert Guide To Energy Management In Buildings
• The Expert Guide to Solar Technology and
• The Earthscan Expert Guide to Retrofitting Homes for Efficiency.

Find out more and buy the books here.

The cheap and reliable form of solar energy storage for homes that is already on the market

How should we store solar electricity? How about as heat? A Swedish research team is storing solar energy in liquid form, but it is still a way off being commercially available. A competing technology using molten salt is already on the market and shortlisted for a major renewable energy prize. But there is already a much cheaper and already well-proven solution now being used in a brand new context...

A shorter version of this article has appeared on The Fifth Estate.

The problem

Solar photovoltaic power it is increasingly being installed on buildings but a major challenge is that it is difficult to store so that it can be delivered when needed.

Storing solar electricity as heat is useful because the world uses more than twice as much energy in the form of heat as electricity. So for solar power to become ubiquitous, it needs to be delivered as heat more than as electricity – and round the clock.

Liquid solar energy

The solution of researchers at Chalmers University of Technology in Sweden is a chemical liquid that can tranport solar energy and then release it as heat whenever it is needed. The research, described in March’s edition of Energy & Environmental Science, describes how the team came up with a way of copying the means by which plants store solar energy – in molecules.

Transforming it into bonds between atoms in a liquid chemical makes it possible to transport it as well as store it.

“The technique means that that we can store the solar energy in chemical bonds and release the energy as heat whenever we need it,” says Professor Kasper Moth-Poulsen, who is leading the research team.

“Combining the chemical energy storage with water heating solar panels enables a conversion of more than 80 per cent of the incoming sunlight.”

The research project has come a long way since it began six years ago when the solar energy conversion efficiency was 0.01 per cent and the expensive element ruthenium played a major role in the compound.

Four years later, the system stores 1.1 per cent of the incoming sunlight as latent chemical energy – an improvement of a factor of 100, and ruthenium has been replaced by much cheaper carbon-based elements.

“We saw an opportunity to develop molecules that make the process much more efficient,” Moth-Poulsen says.

“At the same time, we are demonstrating a robust system that can sustain more than 140 energy storage and release cycles with negligible degradation.”

The process is based on the organic compound norbornadiene, which upon exposure to light converts into quadricyclane.

Hybrid panels

The rooftops of buildings can take advantage of the benefits of installing both solar water heating and photovoltaic modules.

Typical efficiencies for photovoltaic modules are now at least 20 per cent. Solar water heating systems have an efficiency of between 20-80 per cent, depending on the application, location and the required temperature.

Solar water heating systems make use of the full solar spectrum, whereas photovoltaics can only harvest a much more limited proportion.

Some companies have used this difference to design hybrid panels which contain both solar water heating and photovoltaic cells, particularly since the water can be used to stop the photovoltaic panels overheating, making them more efficient. The downside is the expense.

The Swedish researchers think that one of the potential applications for their technology, when it has become more efficient, will be a new generation of hybrid panels that utilise the heat, which can be released from the liquid storage medium.

Concept diagram for the hybrid solar panels

They say that combining solar water heating with their system allows for efficient usage of low energy photons for solar water heating combined with storage of the high-energy photons in the form of chemical energy.

Their simulations have persuaded them that these hybrid panels could be up to 80 per cent efficient. In terms of energy density they are comparable to a lithium ion battery.

The team will continue work on the technology to evaluate the potential cost and bringing it down by finding a way to mass produce the constituent chemicals, and to find a non-toxic solvent.

More than a pinch of salt

A totally different technology is from Sunamp, a British company that has developed its technology by collaborating with the University of Edinburgh School of Chemistry. It guarantees low-cost materials, exceptional long life, recyclability, safety and high energy density.

The technology has been shortlisted for the 2017 Ashden UK Awards alongside the work of the Passivhaus Trust and the Carbon Co-op, a community benefit society that helps its members to retrofit their homes.

An engineer installing the solar salt battery.

Sunamp’s form of storage uses a salt as a phase change material. This absorbs and releases thermal energy during the process of melting and solidifying respectively.

Similar technology is used on a large scale with concentrating solar thermal power stations, typically located in hot, arid deserts.

In this case it is used for storing energy from photovoltaic panels, waste process heat, or heat from heat pumps and micro CHP (combined heat and power) systems, in order to increase efficiency.

How does it work? In the case of storing solar electrical energy, an electrical element connected to the solar panels heats up the salt, thereby melting it.

The salt is kept liquid in a vacuum-insulated container. When heat is required, cold water is passed through the liquid in a heat exchanger, absorbing the heat and causing the salt to re-solidify. The heated water passes to the tap and the salt is ready to be charged again.

Sunamp’s batteries come in various sizes and can be used in series, meaning they can be used in anything from small homes to large hotels, for example. They take up much less space than a hot water tank, can store heat for longer and are more efficient.

The battery can store heat at half the weight of hot water in a tank storing the same amount of energy. Whether they are cost-effective depends upon the location and pattern of usage.

The easy solution

Tenants moving into a new passive solar mini-housing estate in Wales – Pentre Solar, Glanrhyd, near Cardigan – have roofs covered with grid-connected solar panels and zero energy bills.

The brand new passive solar homes for affordable social housing, covered in solar panels.

Dr Glen Peters, CEO of Western Solar, which is behind the development, has an ambition for his company to supply 1,000 homes and to work with housing associations and local authorities to provide sustainable, solar-powered social housing.

The occupants of the estate have been given a Nissan Leaf electric car to use collectively, charged by the solar panels on the roofs. So that's one form of storage.

But the homes' heating is provided in a surprising manner, using the best of old technology with new: solar electricity and storage heaters.

An installed storage heater in a passive solar house; proven, old technology meeting the new.

Storage heaters contain thermally massive blocks which are heated up by an element. They then release that heat gradually over many subsequent hours.

This form of energy storage was introduced to British homes in the 1960s and '70s on a special tariff called Economy 7. Since nuclear power stations could not be switched off unlike other forms of electricity generation, these tariffs allowed people to use nuclear electricity at night – at a lower rate when national demand was low – to charge the storage heaters.

The problem was that by the time the heat was needed, the following evening, they were often too cool and many people subsequently removed them and installed central heating instead.

Here, the idea is to let the storage heaters be heated up during the day by the solar panels on the roof, meaning that they are able to provide adequate heating through the evening and night provided that there has been average sunshine (50% of a June summer day) during the day.

This may not be the case in the depths of winter and so the homes are also grid-connected. They export surplus energy when there is some – after the electric car and storage heaters have been topped up – and purchase it when not enough has been generated.

"Storage heaters are incredibly cheap," says Glen, "and a well proven technology. Whereas the storage we had to start with in our prototype house – lithium ion batteries – were designated a fire risk and we had them taken out. They are also much more expensive – a couple of hundred rather than thousands of pounds."

This sounds like a solar energy storage solution that deserves far wider application. Good luck to the other technologies, but if I was looking for energy storage for a house, I know which I would choose.

David Thorpe is the author of a number of books on energy efficiency, sustainable building and renewable energy, including The Expert Guide To Energy Management In Buildings and The Expert Guide to Solar Technology and The Earthscan Expert Guide to Retrofitting Homes for Efficiency. Find out more and buy the books here.

Tory Government in the dock for "shameful" air quality plans

Air pollution in the UK is at unacceptably high levels and the Government has been criticised for not taking the issue seriously, following the release of a “woeful” and “disappointingly unambitious” draft air quality plan, particularly around construction site emissions.

Matthew Pencharz, who brought in the Greater London Authority’s (GLA) regulations for construction equipment while he was deputy mayor for environment and energy, called the draft plan “disappointingly unambitious”, calling on the government to help local authorities enforce environmental regulations on construction sites, and to push the use of clean technologies.

Annual UK emissions of NOx since 2000AD

Emissions from commercial and domestic buildings and construction represent a small but significant proportion of overall UK nitrogen oxide (NOx) emissions. In London, construction equipment accounts for some seven per cent of emissions. These lead to unacceptably high NO₂ concentrations and are important sources of pollution in towns and cities.

Plans slammed as “woeful”

Environmental lawyers ClientEarth had to take the Government to court to force it to publish the Air Quality Plan, with the government fighting against publication until after the general election.

ClientEarth previously had to sue the Government to force it to even produce draft plans by 24 April and final ones by 31 July, as the Government is in breach of the European clean air rules in many areas.

They also last week won a campaign to persuade the European Union to pass tough new industrial pollution rules that, they say, “could save thousands of lives each year”.

When he finally saw the government’s proposals, James Thornton, chief executive of ClientEarth, accused the government of “passing the buck” to local authorities. He said he had no faith in the central proposal – to set up clean air zones for urban areas – without the imposition of charges to deter the most polluting vehicles from entering the zones.

A clean air zone defines an area where targeted action is taken to improve air quality and resources are prioritised and coordinated in a way that delivers improved health benefits and supports economic growth.

“The plan looks much weaker than we had hoped for,” Thornton said. “The court ordered the government to take this public health issue seriously and while the government says that pollution is the largest environmental risk to public health, we will still be faced with illegal air quality for years to come under these proposals.”

Ed Davey, the former Liberal Democrat energy and climate change secretary, called the proposals “not a plan, but a cop-out” while London’s mayor, Sadiq Khan, said: “We’ve dragged the government kicking and screaming through the courts to produce these belated proposals – but they are toothless and woefully inadequate.”

The proposals involve increasing the number of clean air zones from the current six that are in the planning stage to 27. They estimate that this will cut air pollution and provide cost benefits of over £1 billion ($1.76b).

But local authorities would have to exhaust all other options first and they would not be allowed to introduce charging.

Air pollution and construction

Breakdown of UK national average NOx roadside concentration into sources, 2015

While diesel vehicles are by far the largest source of pollution in urban areas, construction sites are also accused of playing their part. Pollution comes from machinery onsite, vehicles going to and from the sites, and dust.

Construction dust is classified as PM10 – particulate matter less than 10 microns in diameter, invisible to the naked eye. It can cause a wide range of health problems including respiratory illness, asthma, bronchitis and even cancer.

Diesel particulate matter consists of soot, sulphates and silicates, which easily combine with other toxins in the atmosphere, increasing health risks.

Diesel is also responsible for emissions of carbon monoxide, hydrocarbons, nitrogen oxides and carbon dioxide. Noxious vapours from oils, glues, thinners, paints, treated woods, plastics, cleaners and other hazardous chemicals widely used on construction sites also contribute to air pollution.

Construction activities can also cause water pollution from diesel and oil; paint, solvents, cleaners and other harmful chemicals; and construction debris and dirt. If land is cleared, soil erosion may send soil into natural waterways turning them turbid and destroying aquatic life.

The website Sustainable Building issues guidelines to construction firms to help them minimise all types of pollution. These include:

• Minimising land disturbance
• Leaving maximum vegetation cover
• Controlling dust through fine water sprays
• Screening the site, skips and trucks to stop dust spreading
• Covering piles of building materials like cement, sand and other powders
• Using non-toxic paints, solvents and other hazardous materials
• Having a policy to manage toxic substances to prevent spills
• Covering up and protecting drains
• Collecting wastewater in settlement tanks then filtering before discharge
• Disposing of remaining sludge according to environmental regulations
• Using low sulphur diesel oil
• Incorporating the latest specifications of particulate filters and catalytic converters
• Not burning materials on site
• Reducing noise pollution through careful handling of materials and the use of sound shields

The UK government’s proposals, however, are confined to noting that excavators and bulldozers and other vehicles or engines used in construction must be approved to demonstrate compliance with pollutant emission standards.

New emissions standards for non-road mobile machinery will come into force in January 2019 and new measures to tackle NOx emissions from generators by the end of 2018.

Pencharz called this response “disappointing” and said it should “do more to push the utilisation of clean technologies on construction sites to save both money and emissions and stimulate this high value manufacturing sector”.

The GLA brought in regulations in 2015 to begin the cleaning up of constructions sites. But the government in its draft only refers to regulations from 2019 for new machines, with no regard to the thousands of older, high polluting ones.

In addition, Pencharz notes, other local authorities do not appear to be being encouraged to bring in London-style regulations and, even if they did, any enforcement powers remain weak.

He points out that clean technologies such as batteries, especially for temporary power for construction and events, would markedly reduce air pollution emissions.

Whoever wins the general election will have an uphill battle improving British air quality cost-effectively.

David Thorpe is the author of a number of books on energy efficiency, sustainable building and renewable energy. See his website here.

When certified smart meters still give wildly inaccurate readings...

How can you trust a smart meter when you know that it gives wrong readings – even though it has passed the certification tests?

Some meters currently on the market containing the technology now known to fail.

Smart meters can provide electricity readings up to six times higher than actual levels, according to a new study. These meters have passed standards tests. However these tests have failed to identify faults because the meters contain components not designed to measure some of the latest devices in use, and the standards have not yet caught up with this.

A version of this article appeared in The Fifth Estate on April 18.

It’s often been a mantra of energy efficiency that “what gets measured gets saved”. But what if the meters used for measuring energy give faulty readings? Two recent market studies have found that such meters are relatively common.

One study by scientists at the Dutch University of Twente found that smart meters can provide electricity readings that are up to six times higher than actual levels.

This unreliability is especially prevalent when monitoring the outputs of LED lighting when they are combined with dimmers.

Tests found that 60 per cent of the meters tested frequently gave results as much as 582 per cent (almost six times) the actual energy use, while some of the meters under-recorded consumption by up to 30 per cent.

Many types of LEDs have not been designed to be used with dimmers, but even those that did generated false readings in some meters. The electricity being consumed has an erratic waveform and many of the meters tested were unable to process this, which caused the inaccurate results.

“Okay, these were laboratory tests, but we deliberately avoided using exceptional conditions,” University of Twente PhD student Cees Keyer said. “For example, a dimmer and 50 bulbs, while an average household has 47 bulbs.”

The researchers dismantled the energy meters tested and discovered the ones giving excessively high readings contained a Rogowski coil current sensor. The meters giving a lower than actual deviation were fitted with a Hall effect-based current sensor.

Frank Leferink, professor of electromagnetic compatibility at the University of Twente, said: “The energy meters we tested meet all the legal requirements and are certified. These requirements, however, have not made sufficient allowance for modern switching devices”.

The standardised test for meters does not make allowance for waveform-contaminating power-consuming appliances. As a result, according to the researchers, it is an unsuitable method for testing meters. Professor Leferink and Mr Keyer advise any consumers who doubt their meter readings to contact their supplier.

In Holland, 750,000 of these meters have been fitted. The network company responsible, Liander, commented that the problem centres on meters installed between 2012 and 2014, with large companies most likely to be affected.

However, households with solar panels and electric cars are also likely to have been hit. The Dutch consumers association said that Liander “should be actively looking for the faulty meters and looking at eventual compensation”.

Millions of similar meters may be installed around the world. The only way for their owners to know if they contain the misleading current sensors would be to consult the manufacturer. They would then have to replace the meters at their own cost under present circumstances – an unacceptable case of testing standards failing the marketplace.

The study, Static Energy Meter Errors Caused by Conducted Electromagnetic Interference, was published in the scientific journal IEEE Electromagnetic Compatibility Magazine.

Industrial hot water meters

At the other end of the market, in industry, meters can also be inaccurate due to the temptation to cut costs by purchasing a cheap metering solution.

Water meters currently on the market.

Martin Wardell, managing director of data-logging software and meter company MWA Technology, says problems arise due to the use of low-quality products for metering hot water.

Wardell claims that the use of sub-par meters, whose life expectancy is extremely low, is “an indictment of the lack of care taken by consulting engineers” who fail to recommend or install heat meters using ultrasonic flow sensors. This type of meter will operate accurately for up to 20 years.

Leading manufacturers of energy meters, including Kamstrup, Diehl/Hydrometer and Itron, do not use mechanical flow parts/meters, instead opting for ultrasonic flow parts.

“What we are seeing more during our site visits is the combination of mechanical parts meters integrated alongside ultrasonic meters, resulting in the performance breakdown of the mechanical counterpart and the inevitable leaking,” he said. “Picking the right meter from the start saves money and complications.”

He puts the blame on estimators in building services and system integrators.

“They have been weaned on this low-cost solution and have the approach that as long as they perform for 12 months, they can wash their hands of any future issue.

“While many consulting engineers have realised that heat meters must be MIS Class II certified, when it comes to specifying water meters they specify WRAS approved and MID certified but they fail to specify the accuracy class. This should be R400 minimum, which are UK water utility grade meters.”

Standards for all energy meters can be found on this European Union website.

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David Thorpe is the author of a number of books on energy efficiency, sustainable building and renewable energy, including The Expert Guide To Energy Management In Buildings and The Expert Guide To Energy Management In Industry. Find out more and buy the books here.

Skills gap challenges the rise in offsite construction

Offsite construction methods for building are on the rise, but there is concern over a lack of the necessary skills to meet the increase in demand.

Factory where building sections are assembled before delivery to the site.

A version of this article appeared on The Fifth Estate on 27 April.

Offsite construction for both office and house building – where sections are assembled in factories then transported to the building site for assembly – has a number of advantages:

• Greater speed of construction
• Lower assembly cost
• Higher quality and sustainability – especially airtightness for energy efficiency
• Increased reliability
• Improved health and safety
• Less disruption to the site’s neighbourhood.

Its use is increasing. In a recent UK survey, 42 per cent of employers with over 100 staff said they expect to be using offsite construction methods more in five years’ time, and all of them said they expected the use of precast concrete panels to increase. In particular, 91 per cent anticipated the use of precast concrete frames to rise.

Percentage by which construction companies think offsite construction will increase over the next five years.

Types of offsite construction and how much companies expect them to increase over the next 5 years.

Benefits

The benefits are potentially huge. In the UK the use of “flying factories” by Skanska and Costain for phase one of the Battersea Power Station housing redevelopment resulted in a 44 per cent cut in cost, 73 per cent less rework and a 60 per cent reduction in time.

In another case, 80 per cent of the Leadenhall Building was constructed offsite by Laing O’Rourke, resulting in a 50 per cent reduction in deliveries to site. The same was true of Vinci’s Circle Health building in Reading, England, resulting in a 20 per cent program reduction and a 28 per cent cost saving.

Half of the clients of building companies expect offsite construction only to increase, according to the report. But if this is to happen, from where will the skills to meet this demand come?

The skills gap

The report outlines six key skills areas related to offsite construction:

• digital design
• estimating/commercial
• offsite manufacturing
• logistics
• site management and integration
• onsite placement and assembly.

 Offsite construction skills and functions.

Increasingly, workers will need these skills to move between offsite and onsite environments and so the training for these six areas must evolve to meet the changing demand, says the Construction Industry Training Board (CITB).

Of businesses expecting to use offsite construction over the next three to five years, 38 per cent told the CITB they believed they will need new or significantly improved skills within their workforces. Handling and assembly skills are those most in demand, with 81 per cent of employers citing them.

Seven in 10 also mentioned skills relating to the operation of powered equipment, health, safety and welfare, site preparation, disposal of waste, team working and quality control.

Mark Farmer, author of the 2016 Farmer Review on the future of construction for the UK Government, says there is a need to attract high quality talent from among the new generation of students who aspire to a very different, digitally led career.

In the foreword to the new report by CITB, he says we need a two-pronged approach:

“Firstly, adopting more integrated precision engineered ‘pre-manufacturing’ techniques, in turn supported by growing client led demand. Secondly, to evolve a new skills and training landscape alongside the more traditional pathways that enables and supports the implementation of innovative techniques and technologies.”

So let’s take a closer look at the emerging required skillsets:

Designers

Designers will need a new range of digital capabilities. Arguably the most important is the adoption of 3D digital models with rich data (using Building Information Modelling) so that designs can be robustly tested and agreed in advance of manufacture to avoid costly errors and modifications at later stages.

Aligned to this is the need to integrate the design function into early stage planning with the contractor and client. This is a significant break from the norm and challenges designers to adopt a more holistic approach to their role.

Estimators

Given that cost saving is one of the key advantages of offsite, the estimating function becomes an even more crucial one in the sector.

Estimators must account for – and have an understanding of – materials used, transportation costs and risk factors.

For offsite projects, the costing model often puts a far higher proportion of the cost at the outset (that is, before being onsite).

But this can deter clients. Being able to make the case for an alternative value proposition is, therefore, vital.

The technical skills required include developing whole life cycle costs, analysing tender documents and contracts, developing tenders, and understanding the use of BIM.

Offsite manufacturing skills

Offsite manufacturing requires technical skills, like welding, joinery, pre-casting and steel fixing, already present in the construction workforce, plus product and process knowledge.

Product knowledge of concrete, light gauge steel, hot rolled steel, open and closed timber frame, cross laminated timber and structural insulated panels are perfect for most factories in the current market.

Many factories use traditional trades, meaning there is still a healthy market for these skills and those who train them.

However, a growing number of companies are moving towards having multi-skilled operatives who are comfortable with a wider variety of tasks and responsible for quality assurance of finished components.

This means that machinists and other multi-skilled operatives would benefit from basic design knowledge to understand what a finished output should look like and to address any issues that might affect assembly onsite.

Logistics

Offsite logistics requires more patience and control, while the traditional function is frequently “more chaotic”.

Much of this skillset revolves around coordination and integration, so it is important that those involved develop soft skills such as listening and distilling information, as well as problem-solving capabilities.

As with other functions, skills in understanding and using digital models and data become vital here, particularly with regard to planning and project management.

Onsite assembly

Onsite assembly often relies on pre-existing core “tradespeople” skills. However, additional skills, both technical and soft, are also required, together with those traditional ones.

For instance, a crane operator needs new skills in handling much larger, unstable pre-manufactured loads.

Similarly, ground workers need to work to much tighter tolerances so that foundations match precisely the dimensions of the components being assembled.

Technical understanding of products and materials is a key requirement across all roles.

Quality assurance, process management and problem-solving skills are also crucial competencies for both assemblers and site supervisors.

Site management

Adaptability and communication are the key skills for the site management function when it comes to offsite construction.

The role hinges on being able to integrate onsite and offsite functions in one project. In this sense, soft skills, such as time management, attitudes and behaviours are arguably as important as technical skills.

Digital skills are required in reading and using BIM models, to help with correct sequencing and installation. Quality assurance skills and behaviours are also important.

The way forward

Whereas there will always be a space for onsite construction, at least some offsite construction for a project offers so many benefits that it is bound to increase. The infrastructure and industrial sub-sectors have been somewhat slower to adopt the offsite agenda than housing and office space, but they are expected to catch up.

Steve Radley, director of policy at CITB, says:

“The greatest potential currently lies within the housing and commercial sectors, where mass customisation can create the buildings we need more quickly and to higher standards. There are also opportunities to bring the benefits of offsite to large-scale infrastructure projects.

“Successful offsite management hinges on the effective integration of both onsite and offsite functions – and this requires a comprehensive understanding of both aspects,” he adds. 

For anyone considering starting out in the industry, this is a good message to take on board.

David Thorpe is the author of a number of books on energy efficiency, sustainable building and renewable energy, including The Expert Guide To Energy Management In Buildings. Find out more and buy the books here.