For those unfamiliar with the PassivHaus Standard, you may be wondering what all the fuss is about. Well here are three simple reasons why you should choose PassivHaus.

1. The standard is proven in use: 20 years of research including monitoring of hundreds of completed projects backs up the methods used to calculate building performance.
2. You will know definitively what your heating costs will be: PassivHaus has absolute thermal performance parameters that are assessed by a third party.
3. Comfortable and healthy: In addition to low heating bills, the PassivHaus standard addresses thermal comfort and Indoor Air Quality ensuring that you always feel warm and the air is always fresh.

Contact us at Energy architecture NZ Ltd for more information.

Most of our current stock of buildings will be in use for quite some time. Because of this fact, improving standards for new buildings is only part of the approach to reducing energy consumption and improving public health.

 In the previous blog post, I mentioned how some European countries have passed legislation that encourages retrofitting the existing building stock for improved energy efficiency. The example we will look at here is the German Energy Conservation Act and the initiatives this legislation promotes. We’ll keep to the basics to show how regulatory change and funding can encourage sector wide changes.

Funding for the Energy Conservation Act is provided by the German public investment bank. As of 2011 they were providing €1.4 billion a year towards the refurbishment of existing homes and other buildings for improved energy efficiency. The goal is for all existing buildings to be refurbished by 2030.

This funding for this program is managed as follows:

1. Interest free or low interest loans (averaging around €36,000 per home) are provided to property owners to fund retrofitting.
2. Funding priorities are new insulation, better windows and doors and more efficient heating systems. 
3. Renewable energy is funded only in combination with the above measures so that any energy generated will cover a greater proportion of energy used.
4. Loan repayments are connected to a proportion of documented energy savings. This is to facilitate immediate benefit from reduced energy bills. 
5. The loan itself is tied to the property, not the property owner.  This is to encourage owners to undertake retrofitting even if they are unsure of how long they will remain in the property. 
   

This program has been running for over 10 years in Germany and has proved very successful both in terms of the number of projects retrofitted and a positive affect on the German economy. The key lessons from Germany indicate that a more ambitious scope of measures leads to greater public participation and that qualified expert advice is essential for achieving projected energy savings.

So what should we do in New Zealand? In both Germany and the UK, exemplar projects were constructed and monitored to establish which energy efficiency measures were best suited for funding. ECD Architects in London (who I used to work for) were heavily involved in UK exemplar projects funded by the UK Technology Strategy Board.

Many different agencies and private companies are involved in similar exemplar projects throughout New Zealand. EECA is probably best placed to coordinate monitoring and funding as they are already involved in research. They also have the beginnings of a wide range retrofitting program for energy efficiency in the Warm Up New Zealand insulation programme.

Obviously what has occurred in Europe and what would be needed here in NZ is a matter of government will rather than physical change. Regardless of your political views, investing in energy efficiency has a sound business case especially when health benefits are also considered. 

Anyone who visited the show would have noticed that heat pumps made up a large proportion of exhibitor stands. Whilst heap pumps considered in isolation are a more energy efficient means of heating your home, their proliferation on the market is an indicator of wider issues in housing in this country .

The mantra of low energy architecture is fabric first, translated as: spend your capital on insulation, good windows and airtightness before you investigate heating and renewable energy. This may be easier to apply with new construction, but is more difficult to apply when renovating. Listening in to conversations at stands exhibiting insulation products for renovating was akin to hearing an insurance salesperson list policy exclusions; building consent required in some situations, underfloor insulation not always achievable, flat roofs can be problematic. In contrast, heat pumps and other bolt on accessories for energy efficiency sail above all these issues.

So why, despite these difficulties, is a fabric first approach so important when looking to improve our existing housing stock?

If we take a 4kW heat pump in a 150sqm house in Wellington or Christchurch as an example.

1. In an uninsulated house this much heating output will struggle to heat one room to 20 degrees in winter.
   
2. In an average new home, this much heating output will heat an open plan living area to 20 degrees in winter.
   
3. In a low energy house, 4kW will heat the whole house to 20 degrees in winter.
4. In a PassivHaus, 4kw is too powerful; 1.5kW is sufficient to heat the whole house to 20 degrees in winter.

Most of the housing that is here today will still be here in 30 years.  If you are approaching the issue from a government point of view, encouraging fabric improvements are easy pickings. The way to access this opportunity is to change the regulatory and economic environment so that conditions are more favourable for home owners and landlords to invest in these measures. Other countries such as Germany and the UK have come to this conclusion and have instigated the necessary changes to positive effect (This topic will be covered in a later blog post). So in the meantime, if you are struggling to keep your home warm, seek out, take advantage of and support centralized measures for improving energy efficiency in housing. And make sure you've done all you can to insulate and draft proof your house before shopping for a heat pump.

http://www.guardian.co.uk/environment/blog/2013/may/17/switching-supplier-energy-consumption

http://www.greenbuildingstore.co.uk/page--stories-mews-passivhaus.html

It's a 2010/2011 report but its conclusions are still valid. 

Good news about the Home insulation scheme. We should expand the scheme into a broad focus retrofitting program for energy efficiency.

Wellington Home Show this weekend www.homex.co.nz. Remember- insulation, airtightness and good windows are your first priorities for energy efficiency.