The NZIA Bulletin sent out on the 26th of January raises an issue of unsubstantiated claims. The examples cited were an internet provider and a solar panel retailer, however, the lesson applies equally to architecture, building design and more specifically Passive House. Here’s the relevant section of the Bulletin:

“…a recent warning from the Commerce Commission has highlighted how important it is for businesses to have reasonable grounds for any claims or implications they make about their goods or services. The warning was issued on Monday 18 December to 2017 NZ Fibre Communications Limited (“Stuff Fibre”) for making unsubstantiated claims that it is “Probably NZ’s Fastest Internet.”

Stuff Fibre has admitted it did not know if its broadband services were actually faster than that of its competitors and that it had not undertaken any broadband speed comparisons. Stuff Fibre, therefore, had no reasonable grounds for making the claim. The Commission’s investigation found that by making this claim without any reasonable grounds at the time, Stuff Fibre is likely to have breached the substantiation requirements of the Fair Trading Act 1986.

The Commission took the stance that business cannot rely on qualifying a verifiable claim with the word “probably” to get out of the fact it had not actually done its research, and that this caveat was ineffective to prevent potential consumers from being misled.

Last month, solar panel systems retailer New Zealand Home Services Limited (NZHS) was issued with a similar warning over claims it made about the financial benefits of its solar panel installations.

It is important to remember that a claim is unsubstantiated if a business or trader does not have reasonable grounds to make the claim at the time they make it. This applies irrespective of whether the claim is an express or implied claim and irrespective of whether the claim is false or misleading. As you think about the year ahead, take the time to reflect on any claims you make about your goods and services.”

Passive House (or ‘Passivhaus’ in German and sometimes used for clarity) refers specifically to the international Passive House Standard as developed, defined and administered by the Passive House Institute in Darmstadt, Germany. Passive House has a very clear definition and set of requirements so it is possible to check if a building meets the definition and requirements of the standard. It is not a tick-box exercise: rigorous modelling and verification are required in the design and construction stages.

Passive House is not ‘Passive Solar’ or ‘Passive-something’, it is a defined standard.

The modelling and design can be undertaken by a qualified Passive House designer or consultant who may also be the architect or they can be independent of the architect. VIA architecture do both. We undertake projects where we are the Architect and Passive House designer providing an integrated service. And we engage in projects as an independent Passive House designer where another Architect or designer is already engaged.

Independent verification is provided by an accredited Passive House building certifier. There is currently one Passive House certifier in NZ, Jason Quinn of Sustainable Engineering. A certifier from abroad can undertake the role, however, there are advantages of working with someone in NZ who is familiar with the climate and construction practices here.

The Passive House design and building certification process together ensure the customer or end user gets something very specific: a Passive House building. And with this comes the quantifiable benefits associated with the standard.

If anyone claims that a building is a Passive House, they will be able to substantiate the claim. You should demand this.

If you’d like to learn more about the qualitative aspects of Passive House, start here: What is Passive House (Passivhaus)?

Planning to build your own Passive House? Visit the Resources page to make sure you start in the right place and talk to the right people.


Notes:

  1. The Passivhaus Trust in the UK provides some specific guidance on ‘Claiming the Passivhaus Standard in the UK‘ with a technical paper available for free download. Much of this guidance also applies in NZ if you are interested in understanding the technical details.
  2. There has already been a court case in the UK where a building was claimed to be a Passive House but wasn’t. Needless to say, the party making the claim lost in court.
  3. Commerce Commission NZ has a good guide on false, misleading or unsubstantiated claims.

To get a warmer, high-performance home, the first thing people think of is increasing the amount of insulation. Thicker insulation than Building Code minimum is important. However, did you know that insulation must also be continuous to be truly effective?

Gaps in insulation are like gaps in your ski suit when you’re on the slopes. Cold comes in and your heat goes out. And, like a lovely cosy ski suit, the thing with thicker insulation is that heat goes out gaps even faster because you’re warmer inside.

In addition to the discomfort and higher bills, the trouble with heat leaving your home through gaps in the insulation is that you get a cold spot in the structure. Cold spots are where condensation can form and over time mould will grow.

This often happens in places in the building structure where you can’t see it – until it becomes a major issue, that is. And by then it could be affecting your health and the durability of your house.

Where insulation is left out is one type of gap, the other type of gap is where a solid material goes through the insulation – like the edge of a concrete slab. This is a “thermal bridge” or “cold bridge” – where a material that conducts heat bridges between the warm cosy inside and the cold outside. (Read more on thermal bridging here.) Literal gaps in the construction where cold draughts come in is another kind. (Read more about draught-free construction here.)

If you already have a design, the easiest way to check if your home is designed for the insulation to be continuous is to use a red pen to draw over the plans and sections from your architect or designer. Or ask them to. The red line of insulation should be a continuous loop in any drawing. High-performance windows and doors are part of the insulation line.

If it’s not continuous, you should ask why and insist it gets corrected. You’ve got to get it right at the design stage to have any chance of it getting built right.

You might need to educate your Architect or designer if they aren’t familiar with high-performance design.

This is one of the topics, I often find myself discussing during an Expert Consultation where we review your project feasibility together. An Expert Consultation is the ideal first step towards commissioning me as your architect or engaging me as your specialist consultant (or Passive House designer) for the high-performance aspects of your design if you’re already working with an architect or designer. It’s a straightforward service for a very reasonable fixed price. All the detail are here.

A continuous (red) line of insulation ensures a high-performance outcome. (c) VIA architecture

“Passive House” refers to the international Passive House Standard, sometimes also referred to using the German spelling “Passivhaus”.

The Passive House Standard is often referred to as “the world‘s leading standard in energy efficient design.” And usually, a description of the standard includes details of the specific technical requirements.

The Passive House Standard is an international, rigorous, scientific, performance standard for the design and construction of energy efficient buildings. It applies to all kinds of buildings, not just houses. However, the Passive House Standard is not just about the technical requirements of energy efficient design, it encompasses:

What do Comfort, Energy Efficiency and Quality Assurance mean in practical terms for a house that is certified to the Passive House Standard?

Exemplary Comfort

A house that is certified to the Passive House Standard provides exemplary comfort all year round. While the standard is most well-known for rigorous energy consumption benchmarks, it also has rigorous comfort benchmarks.

The Passive House Standard ensures that a house can be affordably and reliably kept at a comfortable temperature all year round. This is true in hot periods of the year and in cold periods. The actual temperature inside the house is up to you though – some people prefer a cooler house, others prefer a very warmer house.

The comfortable temperature inside the house includes all the rooms and the surfaces of walls, windows and doors, etc. The Passive House Standard requires high-performance windows and doors so that the frames and the glass never feel cold to touch or be near. This also has the benefit of eliminating condensation, which can lead to mould growth and associated health risks.

The Passive House Standard ensures that a house is quiet inside and does not suffer from draughts.

The Passive House Standard ensures that a house always has plentiful clean fresh air. A ventilation system is required in most climates to comply with the standard. This means that even when it is cold and windy outside, or hot and dry, there is still fresh air silently and gently blown into the rooms of the house at a comfortable temperature. Windows and doors can still be opened whenever you want to, just like any other well-designed house. Equally important though, windows can be closed whenever you want to and there will still be plenty of fresh air throughout the house.

Radical Energy Efficiency

A house that is certified to the Passive House Standard uses very little energy to stay exceptionally comfortable all year round – and for you to do all the other things that you would expect to in your house. The Passive House Standard accounts for all the energy use in a house, from the heating and cooling, the cooking and lighting, through to TV and computer use.

Passive House ensures that your house uses very little energy because of the way it is designed and constructed. It does not rely on adding renewable energy generation systems to provide (or offset) some of your energy needs, although this is possible. It also does not rely on you making dramatic changes in your lifestyle to use less energy.

The result is that a certified Passive House could be using up to 90% less energy that an average house. And it comes with exceptional comfort, far better than any other house. Even compared to a typical new house, which is expected to be more energy efficient than average, a house certified to the Passive House Standard would expect to use up to 75% less energy. And this means power bills reduced by up to 75% also!

Passive House Benchmank for a Pleasant Home

Reliable Quality Assurance

What good is a standard that doesn’t live up to its promises? (Or a Building Code, for that matter?) The Passive House Standard is one of the very few sustainable design standards that has a robust and reliable track record of delivering what it promises – exemplary comfort and radical energy efficiency.

Passive House requires that the Passive House Planning Package software (PHPP) be used to model the house and the energy use. The PHPP is a very detailed spreadsheet developed by the Passive House Institute. It reliably and accurately predicts how much energy will be needed to keep a house comfortable at the required benchmarks.

The Passive House Standard requires that an independent third party, the certifier, check the energy modelling (PHPP) as part of the certification process. They also check key aspects of the design including construction details.

The Passive House Standard also requires that the construction process is monitored to ensure what gets built matches the design accurately and that the builder takes personal accountability. Visual inspections are carried out as well as blower door tests to check the quality of construction. Where changes are needed, the energy model and details need to be updated and checked also.

These all add up to a very robust quality assurance process. Designers and builders are more vigilant knowing their work will be checked and verified. And honest mistakes can be picked up and corrected before something gets built wrong!

Passive House Standard

he Passive House Standard is the benchmark for exemplary comfort, radical energy efficiency and reliable quality assurance.

And it needs all three aspects. Energy efficiency is meaningless if your house isn’t comfortable and pleasant to live in. And a standard is meaningless if it doesn’t deliver what it promises. A house that is certified to the Passive House Standard will keep you comfortable and pleasant all year round with hardly any energy bills to pay!

The Passive House Standard is the benchmark for exemplary comfort, radical energy efficiency and reliable quality assurance.

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