How 475 can help you achieve a high performance home

Ken Levenson admits to being 'obsessed with climate change' as architect and created 475 to help others get easy access to high quality, Passive House products.
Ken Levenson admits to being ‘obsessed with climate change’ as architect and created 475 to help others get easy access to high quality, Passive House products.

So, you’ve decided you’d like a really good home. One that’s comfortable, healthy and energy efficient. That’s great, but unfortunately it’s not (yet) standard practice. Hopefully you can find a good designer to help (try this list if you like). But you’ll also need some good, non-standard products. This week I spoke with Ken Levenson about how 475 can help you achieve a high performance home.

Obsessed with Climate Change

Ken reminded me of why I do what I do. My interest in creating better places to live stems from wanting to help improve the natural environment. As many in the building industry have recognised before me, I now understand that people are more likely to look after their own environment (i.e. their home) first and then think about the rest of the planet.

The opportunity we have whenever we build or renovate is to look after both ourselves and the planet at the same time.

Ken admits to becoming obsessed with climate change when working as an architect. He came across Passive House as a solution to energy efficiency.

What is 475?

475 is short for 4.75 kBtu/ft²yr (kilo British Thermal Units per square foot), which is the Passive House standard for energy use. As someone from the metric half of the planet, I have no idea what this means!

Fortunately, Ken was able to translate for me:

4.75 kBtu/ft².yr = 15 kWhr/m².yr

Hence 475 High Performance Building Supply was born.

475 supply high quality insulation, draught proofing material and ventilation solutions for high performance buildings.
475 supply high quality insulation, airtightness and ventilation solutions for high performance buildings.

How can 475 help you create a sustainable house?

Soon after discovering Passive House, Ken realised that it was hard to find the right products for the job. He also realised that others might be facing a similar procurement challenge, hence 475 was created to make high quality insulation, airtightness and ventilation products easily available.

Selling Sustainability

Saving the planet is not everyone’s motivation for building a high performance home. Mostly people are motivated by:

  • Comfort
  • Health
  • Saving money on energy and running costs
  • Indoor air quality

Fortunately, building to Passive House standards will help achieve all of these, so there’s something in it for everyone!

How to Create a Hight Performance Home

Ken’s tips for a high performance home:

  1. Thermal mass and orientation
  2. Continuity of the insulation and airtightness layers
  3. Integrating windows (and other holes) into the design

(This bears a strong resemblance to Map, Wrap and Gaps)

Find out More

475 have loads of great resources including an informative blog, a free ebook, loads of CAD details and much more. You can also connect with them on:

  • k copp

    At one point he is quoted as saying buildings in NYC have a heatloss of 95 btu/ sq ft. This is incredibly high. Where does he get this number?

  • k copp

    No comment after 2 weeks? I Don’t think the 95 btu / sq foot number is correct.

    • mcutlerwelsh

      Hi k copp. Thanks for following this up. It’s my fault for not getting a response. I’ll chase one for you.

    • Ken Levenson

      I haven’t listened back, but I think I said 4.75 represents about a 95% reduction in heating demand from NYC typical….that puts you at about 100kbtu/ft2*yr range…. Or I might have switched that…but they are close and yes, big numbers. I don’t have the source(s) at my finger tips but I can circle back with it. No problem.

      • mcutlerwelsh

        Thanks Ken, and I recommend your blog too, for anyone interested in diving more into this stuff…

      • kcopp

        Maybe we are using different measurements….
        How did you arrive at that number?
        Did you base it off the sq ft of the building and the boiler size?
        What a heatloss w/ manual J done?
        A typical home here in NH has about 20 btu/ sq ft. 2×6 Frame construction, fiberglass insulation.

  • What we need today is real building science and not Bandaid suppliers. These companies offer solutions to get contractors and architects looking good now, using substandard or just plain wrong solutions for obtaining low maintenance structures long term. Faced with small simple mistakes could cause massive repair bills to return homes back to compliance. Using better spec materials to begin with there is no need for any of 475 solutions, As I see it it’s putting lipstick on the PIG till everyone comes to their senses. People want solutions so almost any message is received when no direction is offered by the originators of the Passive House Movement. Messages of their product being a panacea for centuries old construction methods are just plain misleading and at some levels, wrong. Here is a example of what OSB looks like when soaked in water, minus the tapes..

    • Ken Levenson