
HPH336 : Ben’s Passivhaus 5 years on
Ben Adam-Smith marks five years of living in his Passivhaus home by reflecting on his self build journey and what the house has been like to live in.
Find out more about my project in the archive
When I set up House Planning Help in 2012, at the back of my mind was the desire to build a house.
I learnt a lot over the next few years and finally secured a plot of land at the end of 2016, going through the architectural design process in 2017 and ending up in my new home in October 2018.
Episode 235 has links to all the podcasts I made going through the project. There's also an episode where I reflect on my performance as a self-builder!
And if you want to take things further, there's a complete in-depth video case study in our membership community The Hub.
Overall we are immensely proud
Self build is a privilege. Not everyone gets to tailor a house to their needs so we are most grateful for having had the opportunity.
Building a house when your kids are young is a juggling act but there's a massive pay-off if you can get through it all unscathed.
We have a home we love… and our kids can grow up with a bit more space and comfort.
Having an experienced team helped massively
Building a house is a team activity and we were blessed with a skilled, supportive team.
A big thank you to Parsons + Whittley (Chris has since retired and closed his practice), Mars Builders (Mark has since retired but his son Ricky is continuing to deliver Passivhaus projects), Gabrielle Blackman and various consultants.
This was our first time building a house and there are plenty of things that could have gone wrong. However, with a strong team around you and the willingness to listen I think it is much harder to go wrong.
Passivhaus delivers on its promises
One of the best decisions we made was building to the Passivhaus standard.
We've talked a lot about the methodology over the years and why it works, but going through it first hand takes you to a whole new level of understanding.
From an occupant's perspective you quickly forget the problems of traditionally built houses.
The indoor living environment is fantastic
The temperature around the house is constant and even, there are no cold spots and it's draught free.
The mechanical ventilation system deals with moisture, removes smells and provides constant fresh air. It's lovely and quiet. All the space is usable. Summer comfort is a reality. And we can afford to live in this space.
From my experience, living in a certified Passivhaus is highly desirable.
The MVHR system has been our biggest problem
There's not much to go wrong in a Passivhaus as it's all baked into the fabric of the building, but the one piece of kit you must have is a mechanical ventilation system with heat recovery (MVHR). My unit has gone wrong a number of times.
I don't think I will ever get to the bottom of why I have had this much trouble and I'm pleased to report I don't know of anyone else who has had lengthy bad experiences.
It's worth bearing in mind that everything needs maintenance and any equipment will go wrong at some point so specify the best you can, look after it and keep technology to a minimum (following the KISS principle – Keep It Super Simple).
I understand the importance of MVHR in a Passivhaus but my concern is for others who might not be so persistent and will just switch it off instead.
We should have gone with a renewable heating source
In terms of regrets, the most obvious one was specifying a gas boiler.
At the time – remember this was 6 years ago – I thought it was important to offer a future buyer a connection to the local gas main. A few years on and this doesn’t seem so vital.
Not only did I pass up a more renewable option, but I invested in gas infrastructure (so there were costs laying pipes out to the road, getting the company to connect us, etc.).
Although it would not be too complicated to upgrade to an air source heat pump, would it make sense to do it immediately? There's a lot of embodied carbon in my decision.
A timber build system would have made the house more sustainable
Masonry cavity wall construction is still the most common build approach in England. As a newcomer to construction I was keen to understand more about it and hopefully inspire others heading down this path to improve the efficiency of their projects.
As the years have gone by, if anything, it seems like the proponents of masonry cavity wall Passivhaus have turned to alternative construction methods. Considering the embodied carbon and lifecycle of a building is much more important these days.

Join The Hub to access our in-depth video case study of Buckinghamshire Passivhaus, a PH15 build
Client intervention can backfire!
As a client this is your project and of course you are going to feedback so that you get what you want.
However, if you're working with a competent team a lot of experience is worked into their approach, designs, advice, etc.
As the years roll by it's been fun to reflect on some of our decisions.
For example we specified French doors to open out onto the patio because we wanted that inside/outside living. In practice these are cumbersome. We're always worried about the kids crashing into them or the wind catching them. And on the hottest days we definitely keep these closed. So we haven't used them as much as we thought.
On the architects initial plans they had specified a sliding door. While this would only have opened halfway in hindsight I think this would have been a better option.
And there were other instances like this.
When I look at where the kitchen, laundry room and bathrooms originally were I wonder whether they were close together to increase the efficiency of the services. Pipe runs would have been really short (and that means almost instantaneous hot water).
We also messed with the plans a bit. We couldn’t understand why we had such a large utility room when we were still wanting a bigger kitchen.
But the consequence of having a bigger kitchen (more open plan) meant we needed a steel for extra structural support. The way they had done it would have been cheaper.
And then our changes meant the utility room was too small to house the MVHR, so it had to go in the garage!
Did we mess up the architecture on the North East elevation?!
Our changes with the kitchen also meant choosing what to do with the window, because in our horse-shoe style kitchen we’d have a sink in front of one window.
So did we make both the windows smaller or have one big and one small?
Effectively do we try and keep the symmetry (the view from the outside) or have it as we want on the inside?
Initially this was what was proposed
And this is what got built (after client tampering!)
Obviously you are part of an iterative process and things will change but try to understand your plans from the design professional's perspective. And keep asking questions until you feel you have a clear understanding.
Large, heavy doors need constant adjustment
I love the big chunky windows and doors we have in our house.
However, the larger these components get the more work the hinges have to do. No matter how well designed they are, with heavy triple glazed units they gradually go out of alignment.
So we've had to have them reset a few times.
Also bear in mind that large components can catch the wind and when they slam THEY SLAM!
Additional shading would increase summer comfort
Over the last few years I’ve had a chance to experience how a Passivhaus can provide a refuge in extreme weather.
On the hottest day the UK’s ever experienced (40C+) our house was around 25/26C inside.
This is mighty impressive. We have never struggled to sleep at night. It works.
We could go further
As I've visited more Passivhaus buildings I've become fascinated by houses that cut out summer solar gains almost completely. When that happens you enter a whole new level of desirability.
The veranda at Parc Y Rhodyn
This is not advocating for mechanical blinds because they would just be something else that will use energy, require maintenance and go wrong when you least expect it!
Can the building do more work? Or can we introduce some temporary external shading? It's almost a Passivhaus vernacular.
Loose ends
The last few points are just little things that I thought were worth mentioning.
Our driveway turning circle still scares people!
A little bugbear of mine is when people arrive at the house and instead of turning in the turnaround they start reversing up the driveway. It can be okay if they are skilled but all too often people start driving onto the grass.
While I’m reluctant to hand over much more space for a turnaround we may expand it at the pinch point in due course.
I’m not convinced by the kitchen recirculation fan
With mechanical ventilation with heat recovery (MVHR) operating around the house, you don't want to introduce an extract fan in the kitchen because this would conflict what's going on.
Instead you can have a recirculating hood. In our case it is a pop-up recirculation fan with a carbon filter.
The idea is that it takes some of the impurities out of the air. I find it doesn't work that well and so I normally I just leave it to the MVHR if I'm cooking something simple or open the windows for a short time if it's something smelly.
I still love my store room (room within a room)
This happened by accident. My office can also do double duty as a guest room and so we had originally thought about putting in an en suite bathroom. However, we concluded that it would be wasteful as it wouldn't get used that often.
So we kept the space and turned it into a store room.
All these years later I still love this space. My office looks so tidy because any files or other equipment (like the printer) lives in the storeroom.
I would definitely create a storeroom again. Climbing into the attic is a distant memory!
Pop-up plugs in our sinks have all broken
It’s hard to remember little details. I don’t think we bought dirt cheap plugs but it's fascinating how one by one they have broken.
While I don't think this is a result of cost-cutting this is the sort of thing that can happen if you cut costs in the wrong place.

We didn’t cost up the garden plan
If you have pushed your finances to the limit during a house build then there may be some elements of your project that you'll deal with once you've moved in.
For us, it was the garden.
We did commission a plan for the garden but it was always on the agenda to tackle it ourselves.
So each year we tackle another job.
Even with us doing the work it's probably not far off the mark to say we're spending a couple of thousand pounds each year (plants, outdoor furniture, a shed, etc.).
Podcast episodes mentioned
My entire 6-year house build (told through my audio journal)
How well did I do on my self build?
Is mechanical ventilation just something else to go wrong?
Transcript
Please connect with us
Subscribe, rate and review us on Apple Podcasts
Like our Facebook page
Follow us on Twitter