This has been achieved by a combination of active and passive measures. 16 PV solar panels and a 5 Kw battery pack power an air based heat pump and the house is ventilated through an active heat exchanger system. All carbon based heat sources (a solid fuel stove and an oil fired range) have been removed and the chimneys blocked up.

The exterior of the house has been clad with 120mm insulation and the basement studio has been brought into the same energy envelope through similar insulation on the inside of the walls. The ground floors have been insulated with 120MM insulation boards and under floor heating has been installed. Attic insulation has been increased, all windows have been replaced with triple glazing, and all "thermal bridges" between exterior and interior of the house have been eliminated. Finally, a lot of attention was devoted to making the house as air tight as possible.

From a project management point of view the greatest difficulty was the sheer amount of stuff that had accumulated in the house over 37 years when added to the contents of a second home moving in. It was only possible to clear a few rooms at a time and a lot of stuff was damaged due to damp and mould caused by drying concrete floors and temporary storage under tarpaulins outside. A very fine building dust permeates everything and we are fortunate none of us suffers from asthma.

In retrospect we would have been better off paying a removal company to remove all contents and store them off site for the duration of the building process, but then we underestimated both the scale and the timescale of the project. All fitted furniture had to be removed to facilitate the poring of concrete over floor insulation and heating systems and this generated 3 skips full of waste and a lot of replacement costs!

The building contract and government grant towards the cost only includes the enhancement and refurbishment of the shell of the building plus the installation of the energy equipment, so all replacement flooring, fitted furniture, doors, architraves, skirting, painting and decorating is down to us. Fortunately the kindness, hard work, and expertise of friends, relatives and neighbours made this job a whole lot easier. But combined with the demands of a newborn child it has been a busy 6 months!

The main un-budgeted cost over-runs related to unexpected requirements to replace the fascia and soffit in the roof to accommodate the increased insulation, and to "tank" the basement studio walls to prevent any risk of a damp problem emerging between the walls and the internal insulation. For some reason the well water was also disturbed resulting in a need to replace and upgrade the water purification systems.

We're on the home stretch now with the hall and downstairs bathroom only cleared on Christmas Eve. We've got 4 rooms to go in terms of clearing and flooring and painting etc. and a lot of flat pack furniture to buy and build for replacement storage, but the pressure is now off. We have a warm comfortable house with enough space for our immediate needs and the remaining work can be done as time and human energy levels permit.

The garden was transformed into a building site as the work progressed, but that's a problem for next spring and summer. Broadband and TV are still not fully functional (thanks to our suppliers not delivering on their part of the deal!) but our wireless Wifi system is adequate in most parts of the house to meet the most pressing needs, if not up to much for streaming or work usage.

I will try and do a more technical review of the specifications, performance, environmental footprint, cost and energy savings of the house in due course. It is quite difficult to source adequate technical expertise for all these relatively new systems within the Irish building industry at the moment, but hopefully that capacity is growing all the time.

At a personal level, transferring a home from one generation to the next can be quite a transformative experience. I was forced to stay with a friend nearby for almost 4 months during the building process and living out of one bag with only intermittent Wifi was quite discombobulating for me. My thanks for their kindness and tolerance!

It would also be remiss of me not to thank our project manager, Richard McCarthy of Towards Zero Energy, and our chief building contractor Flo of Floelen Construction without whose expertise, dedication and hard work this project would simply not have been possible.

And  now the real work begins: Baby Sam demands my attention!