Newbie from South Cambridgeshire

[Gema]

Hi, 

 

last September we found a plot we liked in South Cambridgeshire and started to look into doing our own self build. This is something we had considered doing when we retire, but plots that align with our requirements are not super abundant, so we decided to do it now instead. We are looking to build a Passivhaus two storey dwelling and have it certified. Energy efficiency is important to us and so is having a home at the end that is really comfortable to live in. 

 

A few months later and we have exchanged contracts and are a couple of months into a planning application, awaiting the final outcome any week now. We started the journey with an architect, but two months into the relationship we realized our timeline would be heavily affected by the fact that we were not totally aligned and not fully listened to (despite very lengthy email threads back and forth) and decided to learn how to do the architecting ourselves, and hire any experts we needed to help with things along the way.  But having a third party handling it all for us was... too low touch for our liking. 

 

We'll be managing the build ourselves, as we've decided against having a main contractor. Maybe we'll need a project manager at some point.  

 

We've been reading the forum and learning from you all, hopefully we contribute something back soon! 

[SteamyTea]

Welcome.

Building to Passivhaus standard is a good goal.

But why do you want the certification?

If it is low energy running and minimum embodied CO₂ and energy you are after, there are cheaper ways to achieve this.

[saveasteading]

2 hours ago, Gema said:

we were not totally aligned and not fully listened to 

So you are right to part. But there are lots more out there and can be inspirational, and some are good technically which can avoid problems.

 

2 hours ago, Gema said:

looking to build a Passivhaus two storey dwelling and have it certified

Up to you of course but that last 5% can be very expensive.

Do you want the 'badge' or simply to have an efficient home?

Some of the issues are a matter of opinion anyway.

But I look forward to your input.

[MikeSharp01]

Welcome Gema to THE forum for people like us.

 

We went down the Architect route to get a good design - we are not aesthetically capable but we had a strict set of criteria and I did the passive house training I felt I needed to be able to keep the architects we finally chose on the straight and narrow - we learned together. We only took them on for the design only and once that was complete we have managed the rest. I think, in hindsight, that I went a bit technical, what my other half calls 'full geek mode' on the build as we chose wooden frame with blown cellulose fibre insulation augmented in places with PU sheets. Its worked out well but could have been more simply done. 

 

So its definitely possible to do this with an architect beyond the design phase but to get a standout design, pretty much every house in our road is different to the next one, I felt and still feel the architect route was a good one for us.

[correctalex]

Hi folks! Gema's other half here! Thanks for the warm welcome.

RE PH certification - it's a relatively minor incremental cost given everything else (especially since we are doing all the design work - so it's really just the certifier cost), and we feel it's actually pretty good value for money, given the extremely detailed review and guidance that comes with it.

 

As for the architecting, it's been a steep learning curve, but well worth it. We found trying to iterate over the design with an architect more tedious than helpful, but maybe that's because we are the ultimate control freaks. Let's just say the architect wasn't loving it when we rocked up with full daylight simulations (using Rhino + Ladybug Tools) and resizing & relocating all his windows, for example. Never mind asking for some up-front PHPP modelling and being told to wait, as that'll come during "detailed design". I'm sure there are plenty of good architects out there, but certainly not the one(s) we found.

 

On the [visual] design side is probably where an architect would have been most useful as we aren't normally the creative types. However, we found our mojo and have concocted something we genuinely like (and is simple-ish to build).

[SteamyTea]

A couple of people have built to Passivhaus standard and I think that @Gone West got certified. But then he did move down my way.

 

As @MikeSharp01 says, it is easy to go 'geeky'.

Good engineering practice will get you to 90%, the thermal properties are not that hard. 

Then, as we often hear in here, you only have 90% left to do to finish.

[Dreadnaught]

Welcome!

 

I am self building (solo) relatively nearby in Cambridge city (at first fix). Be in contact if I may be of any help. 

 

Dreadnaught

[JohnMo]

5 hours ago, Gema said:

This is something we had considered doing when we retire... two storey dwelling

No idea how far you are off retirement, we decided to do single storey, with an eye of getting older and limited mobility, making the house fully future proof. All bedrooms have access to decking as does the dining room and all are level thresholds at the doors. 

 

Single storey makes passivhaus more difficult due to form factor.

 

5 hours ago, Gema said:

architect

We went architect, but on the basis I reviewed and approved all drawings. Treated on a proper engineering basis. He came up with a design I never would have, but to the spec I wanted. I decided build method, insulation, airtightness, designed heating and how to achieve everything. He did the leg work of building regs etc. Worked for us.

 

5 hours ago, Gema said:

We'll be managing the build ourselves, as we've decided against having a main contractor.

Be prepared to roll up your sleeves and get stuck in, it isn't a part time task. If you are working full time and doing a build management, be prepared for delays and maybe not getting what you want.

 

But good luck and enjoy the journey. I did.

[Gus Potter]

8 hours ago, Gema said:

affected by the fact that we were not totally aligned and not fully listened to

This is common, I despair at times that professionals are so bad at listening. It's good for business to do so, to listen and understand Client requirements, it's a common law of business.. just listen and deliver what the Client is asking for, but always question if you think they are doing the wrong thing, something that is unsafe or will destroy their financial investment. Sometimes you do the best you can, but some Clients self destruct.. is this you?  I try and cover their arse professionally so they don't do something stupid.

 

8 hours ago, Gema said:

We are looking to build a Passivhaus two storey dwelling and have it certified. Energy efficiency is important to us and so is having a home at the end that is really comfortable to live in. 

Now why do you want to do this? Is it some kind of liberal thing that you can boast about to your pals or would you consider getting something close or just the same at a good value? You could lose your shirt here!

 

4 hours ago, correctalex said:

RE PH certification - it's a relatively minor incremental cost given everything else (especially since we are doing all the design work - so it's really just the certifier cost), and we feel it's actually pretty good value for money, given the extremely detailed review and guidance that comes with it.

Ah, Absolute pish as you are resticting your choice of contractors. If you know how to design this kind of stuff.. like I do in the day job why are you here on BH asking about it? So no PH is going top cost you a fair bit more. 

 

Ok you have binned your Architect, you are on a mission.. but you have a massive learning curve to go through if you want to make your project a goer. That said if you put in the work then you will reap a massive cost and self satisfaction benefit. Do you have the time to do this? It can be done but you have to be on site a lot.. so you don't end up paying for something that does not get delivered by the contractor. The building business is not for the faint hearted, there are few rules when you get into a dispute with a builder. This is where you make the savings compared with buying a new house off the shelf. 

 

Can you cope with a stand up arguement with a builder on site? To get to passive house standards you have to pay a builder more for the quality of delivery. 

4 hours ago, correctalex said:

However, we found our mojo and have concocted something we genuinely like (and is simple-ish to build).

That is your starting point. Post some sketches and you'll get load of helps on BH from folk that have done it and worn the tee shirt, that might stop you losing your shirt! 

 

If you have a design you want to go for then that is a great start. 

 

If it's you first self build then my advice is that unless you have loads of money ( by emulating PH build and don't mind losing a bit of it|) then just try and go for a practical, maintainable and a well insulated build that will hold it's value. 

 

The above is a bit of tough love.. but best to hear it now than later?

 

But to finish. You have a desing you like..you have suffered a bit of torture.. well done you both. Think.. if self building was easy then every one would do it. Self building is hard and you should be proud of your achievemnets to date, even if you have made some mistakes, everyone does including me. . I've been there, worn the tee shirt, made mistakes that cost me money. But Build Hub was not around at the time. 

 

All the best on the adventure and your best friend will be the folk on BH!

 

[Gone West]

As @SteamyTea said, we self designed to PH standards, but we didn't have PH certification. I modelled the design using the PHPP and ran many iterations to come up with a design that didn't need a conventional heating system. I found the PHPP relatively straightforward to use, but that was helped by my background in mathematical modelling. This was all many years ago using the 2007 version then updated to 2010 version. I was then a member of the AECB and during get togethers, found some of the Architects knew less than they should, although purporting to be PH experts.

[Nickfromwales]

7 hours ago, Gone West said:

I was then a member of the AECB and during get togethers, found some of the Architects knew less than they should, although purporting to be PH experts.

This is prevalent…..”all the gear, no idea”  

 

The number of jobs where I’ve corrected the architects, even PH certified ones, is just astonishing. Flashy websites and zero clue…..last one I beat by 1% in PHPP and I’m not qualified lol. 

 

I find the higher ranking / higher qualified ones often deliver the most underwhelming results; I find the pretty picture and concept for the dwelling is the sole focus, and the clients are a second thought. Not just a blasé statement btw, factual feedback from my many, many interactions, and real world experience.

 

On 04/05/2026 at 15:29, Gema said:

We are looking to build a Passivhaus two storey dwelling and have it certified. Energy efficiency is important to us and so is having a home at the end that is really comfortable to live in. 

Hi Gema (and other half).

 

A really comfortable home will be difficult to achieve if you comply with the many constraints of a certified PH.

 

I have helped folk create homes which exceed PH levels, without certification, complimented with total focus on the folks who will then reside within.

 

Beware the info that is often left to be discovered, when the decisions have been made and the house then built and occupied.
 

Many instances of happy home builders on here, most without PH certification (so the maths have already been done for you ). 

[Gema]

Thanks all for the input, much appreciated. I realize we've touched on a few controversial topics 😅

 

9 hours ago, Nickfromwales said:

A really comfortable home will be difficult to achieve if you comply with the many constraints of a certified PH.

@Nickfromwales - what constraints do you have in mind? We want to make sure we are not missing something here. The requirements around energy efficiency, and around airtightness, don't particularly seem at odds with a comfortable home. Not sure we'd have gotten the same reaction if we had said we are aiming for an airtight home with good insulation 😆

 

 

[Nickfromwales]

13 minutes ago, Gema said:

Not sure we'd have gotten the same reaction if we had said we are aiming for an airtight home with good insulation 😆

You are correct! As you’d then not need the BS that accompanies PH ‘compliance’; windows and doors reduced to manage excess solar gain, locations moved accordingly (often not giving the views you may have wanted), list goes on.

 

Then there’s the PH product list that you MUST not deviate from, with the inflated price tags, or the 4 horsemen will come and behead you.

 

Constraints such as under and over heating, for another example, where one current client (building to PH and getting certified) was essentially a passenger on her architects journey.

 

No time given to consider how she wished to live, and nothing conveyed as to how hot the house would be in summer; when I provoked this conversation the client was told nearly 35 days of the year her PHPP showed an infinity sign, which iirc means >25°C internal temps. Not 25°, above that, and when further provoked by the concerned client, it was estimated that 14+ days would see >28°C “without human intervention”.

 

Similarly the winters would require portable heaters to be brought into rooms to heat the rooms, but “they must feature accurate thermostatic control to not then overheat the room it’s in….. oh, and you’ll need more than one heater too”.

 

Comfortable? My arse!
 

The above ‘design’ meant cross / purge ventilating the whole house, proactively, over the 2 stories all summer, and whatever you do, don’t go out fir the day with the house locked and secure, as that needs babysitting……

 

Btw, she found this out after the house was in production and door and window locations (restrictions) were cemented. Not happy bunnies, and no longer serviced by said architectural practice.

 

Oh, and charged a feckin fortune for the ‘privilege’.

 

I continue to be underwhelmed by most (not all) architects I meet along the way, as it’s all too often about adding to the trophy shelf.

[JohnMo]

36 minutes ago, Gema said:

Not sure we'd have gotten the same reaction if we had said we are aiming for an airtight home with good insulation

You are maybe correct. 

 

Airtightness makes for good comfort as you have no drafts.

 

Good form factor allows less insulation for the same heat loss, compared to poor form factor. We have a particularly poor form factor, so although great insulation, our heat loss doesn't comply with passivhaus requirements. But we have great views from all main rooms and all bedrooms and the vaulted ceilings make for light airy feel to the building. Having our build comply with passivhaus standards would be almost impossible.

 

Life is a comprise, could have build a nice form factor building, but not sure the living experience would be as nice. Currently sat in from a 6m tall bay window, looking out to a Scottish loch, not sure that is compatible with passivhaus heat losses or heat gains either 

Edited 7 hours ago by JohnMo

[awk]

24 minutes ago, Gema said:

Thanks all for the input, much appreciated. I realize we've touched on a few controversial topics 😅

 

@Nickfromwales - what constraints do you have in mind? We want to make sure we are not missing something here. The requirements around energy efficiency, and around airtightness, don't particularly seem at odds with a comfortable home. Not sure we'd have gotten the same reaction if we had said we are aiming for an airtight home with good insulation 😆

 

 

My thoughts have been to aim for PH, but if we fall short because of too much glass or whatever, then OK - I’m not religious - 95% PH sounds good - and a lot better than what we currently live in.

 

As @Gema infers, it would be really useful to understand what PH things people think add no real value, can be done other ways, more cheaply, or whatever.

 

I’m here to learn and would be really happy to save £££ if it doesn’t make any practical difference - what should I be thinking about?

[correctalex]

6 minutes ago, Nickfromwales said:

You are correct! As you’d then not need the BS that accompanies PH ‘compliance’; windows and doors reduced to manage excess solar gain, locations moved accordingly (often not giving the views you may have wanted), list goes on.

 

[...]

 

That's the thing - PH doesn't prescribe anything of what you've described. We don't really want to sound like a bunch of smartasses, but it does feel like there's misconceptions here about what Passivhaus certification actually entails.

 

Everything you mentioned is just plain bad design, Passivhaus certification or not. Don't get me wrong, I'm sure many "accredited" Passivhaus designers/architects make exactly these nonsensical choices in the name of making it easier for themselves, but that in no way means it's a requirement, or even desirable.

 

Quote

Then there’s the PH product list that you MUST not deviate from, with the inflated price tags, or the 4 horsemen will come and behead you.

 

Passivhaus certification doesn't require specific products for absolutely anything. It's easier to get certification with certain certified products, but you can equally get there without.
 

 

Quote

windows and doors reduced to manage excess solar gain, locations moved accordingly (often not giving the views you may have wanted), list goes on.

 

That's simply a bad design choice. As I had mentioned, we took the exact opposite approach, and optimized for daylight & views first. None of that has made meeting Passivhaus targets meaningfully more difficult.

 

 

Quote

No time given to consider how she wished to live, and nothing conveyed as to how hot the house would be in summer; when I provoked this conversation the client was told nearly 35 days of the year her PHPP showed an infinity sign, which iirc means >25°C internal temps. Not 25°, above that, and when further provoked by the concerned client, it was estimated that 14+ days would see >28°C “without human intervention”.

 

Well, 36 days a year above 25 degrees is the absolute maximum Passivhaus certification allows, and it strongly discourages you from getting anywhere near that limit. PHPP & official guidance in fact encourage you to consider how e.g. climate change, not opening windows, etc, affect overheating, and to stay well away from that limit even under various "stress tests". It's a limit, and not a target.

[Nickfromwales]

9 minutes ago, awk said:

My thoughts have been to aim for PH, but if we fall short because of too much glass or whatever, then OK - I’m not religious - 95% PH sounds good - and a lot better than what we currently live in.

 

As @Gema infers, it would be really useful to understand what PH things people think add no real value, can be done other ways, more cheaply, or whatever.

 

I’m here to learn and would be really happy to save £££ if it doesn’t make any practical difference - what should I be thinking about?

Fabric first approach, but no stupid compromises to suffer is always a primary focus, considering this may well be the single biggest expense of your lifetime.

 

Another current client has double-height glazing which at first glance would suggest they’ll roast to death, bit I’ve made the client(s) aware of solar control glazing, and with a few tweaks, and some input from the good folk at Norrsken, it has all passed muster and the fenestration all went in successfully last week.

 

Knowledge is power, and anyone with comprehensive industry knowledge and (lots of) years of experience are defo assets; welcomed oil for the cogs. Start the planning as early as you can, explore every option / nook / cranny, and measure twice build once, well.
 

Results will then speak for themselves!

[JohnMo]

5 minutes ago, awk said:

doesn’t make any practical difference - what should I be thinking about?

Airtight - think about how you will implement with your build method. Airtightness tape, we don't have any in our build. We do have airtight mastic/adhesive, airtight paint.

 

Thermal bridges are cheap to eliminate, but takes thought.

 

Heating system, keep it simple. It's keeper to install generally cheaper to run.

 

Ventilation MVHR is normal, but not the only way (unless in Scotland).  Conditional MEV or dMEV are other options. Cascade MVHR allows reduced ducting etc.

 

Add PV, as much as you can, add battery, add an ASHP to eliminate gas standing charges.  Running costs are as important as anything. Our April energy bill (April has been mostly heating season in Scotland) is about £30.

 

[Nickfromwales]

5 minutes ago, correctalex said:

 

That's the thing - PH doesn't prescribe anything of what you've described. We don't really want to sound like a bunch of smartasses, but it does feel like there's misconceptions here about what Passivhaus certification actually entails.

 

Everything you mentioned is just plain bad design, Passivhaus certification or not. Don't get me wrong, I'm sure many "accredited" Passivhaus designers/architects make exactly these nonsensical choices in the name of making it easier for themselves, but that in no way means it's a requirement, or even desirable.

 

 

Passivhaus certification doesn't require specific products for absolutely anything. It's easier to get certification with certain certified products, but you can equally get there without.
 

 

 

That's simply a bad design choice. As I had mentioned, we took the exact opposite approach, and optimized for daylight & views first. None of that has made meeting Passivhaus targets meaningfully more difficult.

 

 

 

Well, 36 days a year above 25 degrees is the absolute maximum Passivhaus certification allows, and it strongly discourages you from getting anywhere near that limit. PHPP & official guidance in fact encourage you to consider how e.g. climate change, not opening windows, etc, affect overheating, and to stay well away from that limit even under various "stress tests". It's a limit, and not a target.

The Yin to my Yang

 

The actual experiences of my many interactions, producing homes for folk to live in, and then them moving in, is at odds with how blissfully simplistic your post suggests, largely because ‘others’ were left to the mercy of ‘professionals’ that they trusted. You are very different, and are making better, own informed decisions, and have researched the shit out of it, and this will pay huge dividends.