Imagine | Create | Inspire

Imagine | Create | Inspire

Custom Home Building Designs

Modern Sustainable Plans For Home or Business

 Imagine – beautiful, energy-efficient, earth-friendly buildings that don’t cost the earth

Create – passive solar spaces with impeccable West Australian design DNA, plus a touch of luxe

Inspire – good times, great work, green revolutions

Ciaran Rothkamm Home

About ‘C’

‘C’ is for Ciaran; that would be me.

I’ve lived and breathed building design and construction for over fifteen years.

‘Designed by C’ is a passive solar design and project management service for people who want to live lightly in every sense.

I design spacious, airy, luminous homes and workplaces where nature takes care of the bulk of your heating and cooling.

If your dream build is:

  • A beautiful, practical, personality-packed space that fits your site like a glove
  • A building with sound eco-credentials – that’s water and energy-efficient

I’m reaching for my sketchbook.

If your ideal build is:

  • Effortless – project managed by a personable, professional construction sector veteran who’s designed, drafted, estimated, scheduled, and overseen hundreds of home and commercial builds
  • Exceptional value for money – it exceeds your expectations for clever, creative design, respects your budget, is impeccably built, delivered on schedule, and pays attention to details you may never have spotted on your own

I’m ready when you are

Passive solar building designs & project management

Passive solar designs inspired by southwest geography and ecology.  If you want a building that celebrates and respects our coastal climate and delicate ecosystems AND you’re keen to do the planet a favour


Passive solar home designs

Eco-friendly and effortlessly elegant, your ‘Designed by C’ home enhances everything you love about living the southwest lifestyle.

Climate and site-sensitive design capture every cooling breeze and a sunny outlook.

Shared spaces for gathering and celebrating in all seasons and for all reasons

Quiet spaces for resting, re-energising, ruminating, working, and creating.

Spaces the work exactly as you imagined they would or better.

‘Ciaran was so great to work with, he was professional, patient, understanding and relaxed through all of the changes we made. His knowledge of not just design but of the building process and all the trades involved helped us to make practical and smart decisions. We highly recommend working with Ciaran for your build project!’

New homeowner – Cowaramup

Sustainable design for commercial buildings

Sustainable design for commercial buildings

Great commercial design creates spaces that are a joy to work in and to visit. Trust your commercial project to me, and that’s what you’ll get.

Your designs will also be compliant and scaleable. I specialise in smooth approvals with no nasty surprises and easy extensions when the moment arrives.

Furthermore, if you’ve secured your team of ace engineers, tradespeople, and interior designers, I’ll collaborate. I can also coordinate if that’s what you need.  If you need help to find good people, I know where they are.

Eco-friendly Interior Design

Eco-friendly interior design

Complement the class and cred of your ‘Designed by C’ build with excellent interior design.

I work with talented southwest designer Tracey Arnold.

Tracy will:

  • Discuss your ideas for colours, textures, lighting, décor including fixtures, fittings, and furnishings
  • Spend a day with you visiting shops and suppliers and making great choices
  • Create a detailed interior design specification for tendering and for the actual build

The result?

No scary surprises at the provisional sum stage or during the build. You get a beautiful, stylish interior that expresses who you are and respects your budget.

‘Ciaran constantly added value to our design with his own innovative ideas. The 3D computer program he uses is outstanding.  It gave us a very clear vision of what our completed house would look like.’

Holiday homeowners, Yallingup

Passive Solar Design FAQ

What is passive solar design?

All humans have it. We’re equipped to soak up and store the sun’s heat and send it out to the bits of our body that need warming up.  Every time you go out in the sun, you experience passive solar energy in action.

Passive solar building design optimises the sun’s energy in much the same way as you do. I design your home or commercial building to take full eco and budget-friendly advantage of nature’s ability to heat and cool it.

‘Designed by C’ buildings capture and store and distribute all the solar energy available on your site.  You’ll see precisely how this works in a 3D plan that illustrates every detail of your exterior and interior elevations.

View a sample 3D plan

Get more information and inspiration from  Australia’s guide to environmentally sustainable homes and The Passive House Institute

Are you an architect?

No. I’m a building designer and project manager. I’ve over fifteen years’ experience in all aspects of creating and constructing beautiful, liveable, sustainable spaces for hundreds of contented clients.

I provide a creative and technically sophisticated design service that incorporates sound architectural principles delivered on budget and on time.

I’m an accredited HIA Green Smart Professional.

I’ve taught passive solar building design and construction to Certificate IV and Diploma students at TAFE and sustainability units for the Builders Diploma at the HIA.

Will you work with my builder?

Certainly, I work with many of the southwest’s most renowned builders. I also partner with a handful of talented newcomers. If your builder belongs in either group or they don’t, I’d be happy to collaborate with them.

What are your fees?

Zero until we’ve had a comprehensive design consult about your project.
Based on our discussions, I’ll provide a formal project proposal that includes my fee. It will be detailed, complete and it’ll respect your budget.

Once you agree to proceed and make a 20% initial project payment, your project secures its place in my workflow.

Learn more about fees and payment stages in this Building Designer Engagement Agreement

Designed by C Logo

A solar passive design and project management service for people who want to live lightly and do the planet a favour.

Quality Business Awards 2023 Winner