As demand for super-insulated and airtight building structures grows, insulating concrete formwork (ICF) is rapidly gaining popularity as a method of construction. But what exactly is ICF, what are its key advantages, and why is it so well suited to passive house and low energy construction?

Over the past year cold snaps, heat waves and severe storms have all brought the reality of the climate crisis home to the UK and Ireland. But with the climate changing in fast and uncertain ways, how can we construct buildings that will remain resilient — and keep their occupants healthy and comfortable — long into the future?

When architect Tony Godwin wandered into a seminar on the passive house standard at Ecobuild ten years ago, it was the start of a journey that would eventually see him design and build his own passive home on a sloping site — and learn some hard lessons along the way to achieving a comfortable, ultra-low energy family home with tiny energy bills.

In the classic story of the three little pigs, the big bad wolf may have blown down the first little piggy’s house of straw with consummate ease — but he wasn’t reckoning with this pioneering, energy bill-shredding Suffolk project, the UK’s first load-bearing straw bale passive house

This skilfully designed new passive house in Blackrock manages to be lightfilled and strikingly contemporary while taking its design inspiration from the very ordinary Dublin street on which it sits.

Generational differences in taste were successfully married by a concern for energy efficiency in this contemporary, award-winning passive house in An Spidéal, which comes within a whisker of the nZEB standard.

A selection of passive & eco builds from around the world, this issue features a boat designed according to passive house principles, with the artic climate in mind, and a contemporary passive house by Key Architects on Japan’s rural Shikoku Island.

The default answer when you want to do pretty much anything to a listed building is ‘no’. The default assumption if you want to achieve the Enerphit standard for retrofit is ‘tackle everything’. So how on earth do you retrofit a listed building to within a whisker of the Enerphit standard — with the blessing of the conservation officer?

Old buildings are tricky to upgrade – especially if external insulation’s not allowed. Utilising a combination of cutting edge building physics and a carefully selected palette of insulation materials, one Victorian stone building has been upgraded to the Passive House Institute’s Enerphit standard, slashing heating demand by 90%

Built in 1850, this home in Dartmoor national park would have relied on local timber supplies for heating until the advent of widely-available central heating. One passive house-flavoured retrofit later, it’s back to its wood-burning roots – only this time with much less wood use, and much higher comfort.

Hastoe Housing, a trailblazer in the development of affordable passive housing, have completed their second scheme in the Essex village of Wimbish — 11 houses whose simple and traditional building methods and materials mask cutting-edge energy efficiency.

In 2014, one couple decided to give up life in a van and convert an old newsagents in Shrewsbury into a very small low energy home, using the principles of the passive house standard as their guide. So how did it work out, and what is life really like in such a small home?

As electricity supply from renewable sources continues to grow, and electricity grids gradually decarbonise as dirtier fossil fuels are phased out, heating homes with electrical technologies like heat pumps starts to make more sense. And in the mild, temperate climate of Britain and Ireland, air source heat pumps are particularly suitable — especially as new build standards of energy efficiency continue to tighten, meaning new homes need less and less energy to achieve comfortable indoor temperatures. But how do air source heat pumps work, what types are there, and how much do they cost to run? Our in-depth guide attempts to answer the key questions.

Architect Tom Duffy has long had an interest in green design, and working on a self-build project for himself and his wife he was able to prove a point: making a modest family home to the highest standards need not cost the earth.

Assessment of thermal bridges is the low hanging fruit lining the path to passive house and low-energy building, according to leading thermal modeller Andy Lundberg of Passivate, who says that taking the time to understand thermal bridging and to minimise and calculate it properly is essential to delivering cost optimal low energy buildings without an Achilles heel.

Rising from the shell of the stalled riverside headquarters of Anglo Irish Bank, Ireland’s financial regulator could be accused of insensitivity for choosing as its new home a site that became a toxic symbol of the banking crisis, but the building is not without virtue: it comfortably surpasses the proposed nearly zero energy building standard while achieving the onerous Breeam ‘Outstanding’ rating for sustainability.

A selection of passive & eco builds from around the world, this issue features a rustic holiday home in New Zealand designed using the key principles of passive house design, and the 26-storey House at Cornell Tech, New York, now the tallest certified passive building in the world.

Even in the era of climate change, there still appears to be something of a split in the world of architects between those who prioritise sustainability, energy efficiency and occupant health, and those who put design and aesthetics first. So it’s refreshing to find that the designer of this contemporary Dublin home put so much attention on insulation, airtightness and indoor air quality — as well as good looks.

Almost a decade after the economic crash, every political party in Ireland now recognises the country is in the middle of a full-blown housing crisis. Similar problems exist in the UK market, but for different reasons. Now, if the political will to fix things has finally arrived, the question remains — what can actually be done about it?

This unique sports and drama hall, inspired by the architecture of local buildings, was built to a new standard that aims to ensure buildings deliver all round health and comfort to their users.

Two spectacular low energy social housing units looking out over Ulva Ferry’s breath-taking surroundings prove to be a superb response to local problems of fuel poverty and lack of affordable family housing.

With low electricity and gas bills and a feed-in tariff from its solar photovoltaic array, this simple, ecological timber frame passive house near the Welsh border manages to make about a £50 profit on annual energy costs.

Set on a picturesque coastal plot in north County Dublin, this eye-catching home was built from clay blocks and strives to balance energy efficiency and comfort with expansive sea views.