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We are all familiar with the fairy tale of the three little pigs; a moral-laden fable about three pigs that construct three houses from different materials. The big bad wolf blows down the first two pigs’ houses, made of straw and sticks respectively, but is unable to destroy the third pig’s house, made of bricks. The story has been told and retold for hundreds of years. However, I think that things have changed…

There have been a multitude of innovations in modern construction techniques of late, so I have decided to take a second look at how affective the pigs’ methods actually were; would the straw and stick homes still fall to huffing and puffing today?

Straw house

With shortages of materials, lack of skills, an ever increasing population and subsequent carbon footprint, there is understandably an enormous demand for a housing solution that won’t cost the earth, both financially and environmentally.

Straw bale construction is one such material that could help achieve this goal. Indeed, a house built from straw goes one step further than helping to alleviate a housing crisis – it can even help the very occupants within that house keep the modern enemy of fuel poverty at bay. Straw bale buildings are so efficiently insulated that they require very little heating, even in the dead of winter.

Where timescales are an issue, straw bale building can also prove to be a worthwhile consideration. Last year saw the first ever straw bale houses hit the market in Bristol. The housing development consisted of seven homes that were erected on site in just nine days, thanks to their precision factory-made panels which slot together perfectly. This speedy turnaround adds to their affordability, of course.

Social Landlord Martin Connolly, responsible for the development, commented on the Bristol homes: “We got into straw bale housing to explore how we could make housing more affordable. What was behind it was concern about homelessness and the environment.”

“In the first instance, we wanted to achieve natural non-toxic house building which sequesters carbon. Hugely insulated and air-tight, the homes produce virtually all the energy they need to run. We are installing rain water harvesting to cut down water and sewage bills, and LED lights, solar panels and an air-source heat pump to reduce light and heating costs. Bath University research shows the running costs can be reduced by as much as 90%. And, as volume of sales increase, we can strive to make the house purchase price even more affordable.”

So, was the first little piggy really that foolish to choose straw over other available materials? Let’s consider the facts; just shy of 4m tonnes straw is produced as a by-product each year by British agriculture. It only takes around 7 tonnes of straw to build a three-bedroom house similar to the Bristol developments. This means that theoretically it would be possible to grow enough straw to build more than half a million new homes each year using straw grown exclusively in British fields. Perhaps not so foolish!?

Stick house

Was the second piggy wrong to build his house from wood? I think absolutely not. Perhaps, considering that the structure fell merely at the exhaling of a wolf, it is his construction skills (or lack thereof) that should be questioned rather than his choice of material. Timber frame buildings are inherently strong, durable and sustainable. Readily available and relatively low in cost, structural timber offers a competitive advantage over many other materials.

Studies suggest that by moving more towards offsite construction techniques, the reputation of the construction industry will improve in the eyes of the younger generation, who above all have a keen interest in innovation, technology and environmental issues. This means that a career within the sector would become a more viable and attractive option, which in turn will help to alleviate the chronic skills shortage currently blighting the industry. Even the second piggy could brush up on his abilities by enrolling in an apprenticeship scheme.

The government report, Construction 2025, highlighted that the poor public image of construction was having a detrimental effect on companies’ abilities to recruit and retain the best talent. The cleaner, safer and more professional setting of a modular construction factory could definitely help attract prospective apprentices and graduates into this relatively new and exciting area of our industry.

Timber is the perfect choice for specifiers who want a precision engineered material that is both cost effective AND sustainable. Structural timber is a low-carbon alternative that offers high structural strength, airtight construction and a traceable supply chain. Therefore it is the perfect choice of material for little piggies with a passion for sustainability and style.

Brick house

Although the hero of the fairy tale is the pig that chose brick above all other materials, the truth of the matter is that there are pro’s and con’s to every material and brick is no exception. Brick homes require very little maintenance and never require painting, caulking or staining. However, this does have a trade-off. Changing the appearance of a brick exterior can be somewhat difficult and expensive.

Homes made of brick are highly energy efficient and therefore remain cool in the summer and warm in the winter. Whilst this in itself is good for the environment, there are caveats and sadly the manufacturing process of bricks almost nullifies this benefit. The manufacturing processes used to create building materials such as cement and bricks are currently accountable for roughly 12% of all emissions of carbon dioxide in the world.

Brick manufacturing especially is very energy-intensive due to the kilns that are used requiring firing for up to three days in order for the bricks within to become hard and strong. Brick kilns operate at about 1100°C and are often kept hot even when not in use. This immense heat is generated using fossil fuels, which emit significant CO2 when combusted.

Houses constructed using brick are durable, energy efficient, highly fire-resistant and low maintenance. This means that they tend to have a higher resale value than their timber beam counterparts. Homeowner insurance is also a lot lower for these very reasons. So whilst savings can be made in the long term, the initial outlay will be much higher if using brick in your project.

Bricks are much more expensive as a building material than timber or straw. Also, whilst largely low maintenance for the most part, when repairs do need to be made they can be difficult, time consuming, highly invasive and expensive. This renders brick a non-cost-effective option for many home builders, regardless of savings that will be made at a later date.

Summary

It is clear to see that each method of construction has both benefits and draw backs. This means that no one method is a perfect solution to meet 21st century housebuilding demands. If the housing crisis, combined with materials shortages and the skills gap are the modern day “wolf at the door”, then it is only through a multifaceted approach that utilises all of the tools and knowledge in our arsenal that we can succeed and thrive as an industry. It’s impossible to tell which material will come up trumps in the end – but one thing we can all agree on is that modular technologies, offsite methods and alternative material usage will play increasingly larger roles in construction as we go forward as an industry. Expect to see a lot more on the topic!

So in summary, does a fairy tale that was first committed to print in the 1840’s still offer worthy advice to the wise and considerate specifier who wishes to keep the wolves at bay? I say “no, no, not by the hair on my chinny chin chin!”

Much-needed homes could be built offsite and delivered ready to be assembled in order to meet increasing demand, if there is more understanding and clarity that the approach is competitive with more traditional methods of construction.

This conclusion is drawn from new research undertaken for the Scottish Government following its challenge to industry to “transform” the way new homes are built as a means to further increase sustainability, boost the rate of supply and create export opportunities to support the drive towards a low carbon economy.

Trade body Homes for Scotland engaged its members, who together deliver 95% of new homes built for sale, in order to assess industry awareness, appetite and readiness surrounding alternative construction methods such as offsite manufactured systems.

With improved quality, sustainability and speed of construction identified as drivers for an increase in the use of offsite construction, the report found no resistance to this in principle from home builders. However, the strong perception that offsite construction is more expensive was found to be the biggest barrier. Concerns were also expressed in relation to control over programming and the capacity of the supply chain to sharply increase output.

The report proposes 11 recommendations that could help address these issues, including how to overcome the knowledge and resource gaps that exists in relation to costing and R&D.

Homes for Scotland Chief Executive Philip Hogg (right) said “With the industry’s capacity to increase production in the wake of the economic downturn currently being hampered by shortages in both skills and traditional building materials, this report is very timely and provides a useful baseline from which to explore how the increased use of offsite construction could help overcome these challenges.”

“However, any such ‘evolution’ must be demand-led and supported by a proven business case that also provides the flexibility the private sector require in delivering products to their customers.”

Minister for Housing and Welfare Margaret Burgess added “We are committed to encouraging companies to utilise offsite modern methods of construction due to the number of potential benefits including economic and export opportunities. That is why we commissioned Homes for Scotland to carry out this research and engage with industry to determine their level of interest in adopting these methods.”

“We will work with the housing industry in Scotland to encourage them to look at these opportunities. This report from Homes for Scotland showing private house builders’ perceptions represents an important step in mainstreaming these techniques.”

Click here to access the “Research into Mainstreaming Offsite Modern Methods of Construction (MMC) in House Building” report.