It was one year ago this month that we moved our furniture from the bungalow up into the house and began living and sleeping here. It had been a long slog to reach this point. So many delays, frustrations, cost overruns - and a great deal of hard work. A few things weren't quite finished, but we didn't want to delay any longer. It was a huge relief to be living here at last and enjoying all the benefits of a passivhaus once more.

On the day we moved in, the internal temperature was a chilly 11ºC. Our passivhaus has no installed heating system, so out came the trusty one-bar electric fire, extra layers of clothing and thick winter duvets. But after a couple of days, the internal temperature had reached a much more comfortable 18ºC. By the end of the second week - with the mechanical ventilation with heat recovery system (MVHR) now up and running - the average internal temperature had risen to 20ºC.

That temperature increase was almost entirely down to our presence in the house: our body heat and activities, such as cooking, using computers and other appliances, and the occasional sunny hour or two. In a passivhaus there are no cold spots or draughts - so the temperature is evenly spread throughout the house and any heat gains remain in the building and don't leak away as they do in conventionally built houses. The MVHR system extracts the stale air from the whole house and passes it through a heat exchanger before expelling it. So all of the heat in the outgoing air is used to warm the incoming fresh air. Before long, winter duvets were exchanged for summer duvets, and the extra layers of clothing and electric fire were put away.

We had some very hot sunny days during the summer which the house also dealt with very well. The heat exchanger in the MVHR goes into bypass in summer, so the fresh air being brought into the house is no longer warmed by the heat in the extracted air. The external framing around the south-facing windows shades the interior well from the full force of the sun, so the house is never in danger of overheating. This is something that can be a problem for buildings with large unshaded areas of south-facing glazing. 

During winter 2021-2022 the house continued to perform very well, retaining an average minimum temperature of 20ºC, dropping by no more than a degree or two when we were away. Our winter duvets have stayed packed away and there's been little or no need for extra-thick layers of clothing. We've used the electric fire now and again, for about an hour at a time, in the evenings - mainly while sitting watching television - but in general it's not needed.

All the hard work of insulating and airtightness-taping, the checking for air leaks and thermal bridges, has paid off. We're very happy with how well the house is performing - and, of course, it's a lovely place to live! 

The months since the March update have largely been spent looking after the land around the house, which we mostly left to grow wild through the summer to let the grasses return and any wild flowers re-establish. This has worked reasonably well and there are very few bald patches remaining. We've planted a few trees, mainly rowans, silver and downy birches, beech, aspen and hawthorn, with a couple of apple trees, a cherry and a wild pear. More tree-planting is planned over on the croft in time.

Two key things have happened since March - our solar PV array was installed and is now up and running, and the part-finished garage has finally been completed.

The PV array was installed on a sunny day at the end of August and so, the moment it was connected up, it began generating electricity. The amount generated varies from day to day, of course, depending on how much sunshine we get, but most days it generates enough to heat the hot water and sometimes contributes to the power used by appliances such as the washing machine or dishwasher.

Our part-finished garage was completed at the start of October (almost exactly a year since it was started!), and the rubbish left from building was cleared away, which was a great relief. Now, all that remains is to finish and fit-out the inside of the garage and move Mike's workbench up from its temporary home in the byre. 

The garage completion marked the final sign-off of the builders, as the year-long snagging period is at an end. The porches still need to be redecorated after damp problems caused by a water leak (now fixed), but it was agreed that we would attend to that.