CUSTOM HOME BUILDER - BOZEMAN, MT
Durable, energy-efficient homes built with craft and science.
Mafic Design Build brings 25+ years of construction expertise and rare Passive House dual-certification to every project in the Gallatin Valley and beyond.
WHY CLIENTS CHOOSE MAFIC
80-90% lower heating & cooling costs in a Passive House vs. conventional construction
25 yrs of design & build experience across residential, commercial & industrial
Dual certified one of very few contractors in Montana certified as both PH Designer and PH Tradesperson
OUR EDGE
Not just a builder who knows about Passive House. A builder who is certified in it.
Most contractors rely on a separate consultant to design energy performance. Stefan Mitrovich holds both the CPHDC (designer) and CPHT (tradesperson) certifications — meaning the energy modeling, the field execution, and the third-party verification all flow from one accountable team.
That integration reduces errors, accelerates decisions, and gets you a home that performs to spec.
Certified Passive House Designer/Consultant
CPHDC · Passive House Institute
Certified Passive House Tradesperson
CPHT · Passive House Institute
Associate AIA · NCARB
MSU Earth Sciences & Architecture
HOW WE WORK
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We learn your goals, site, budget, and timeline. No jargon, no pressure.
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Your home is modeled for performance before a board is cut. You see the numbers before committing.
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Transparent budgeting, clear communication, and Stefan's direct oversight throughout.
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Third-party blower door test and certification. Documented proof your home performs as designed.
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Comprehensive handover with warranty, documentation, and ongoing support.
BUILDING SCIENCE
The building envelope is your home's first line of defense.
The envelope is everything that separates the inside of your home from the outside — walls, roof, foundation, windows, and doors. In a Passive House, it's engineered to be airtight, continuously insulated, and free of thermal bridges. The result is a home that holds its temperature without working hard to do it.
THE FIVE COMPONENTS
Continuous insulation
Improvement-focused, no formal standard
Airtight layer
A continuous air barrier stops uncontrolled infiltration — the source of up to 40% of heat loss in conventional homes.
High-performance windows
Triple-pane, thermally broken frames. No cold glass surfaces, no condensation, no radiant chill next to exterior walls.
Thermal bridge elimination
Structural connections that bypass insulation act as heat highways. We engineer them out at the design stage.
Controlled ventilation
An ERV or HRV continuously brings in fresh filtered air while recovering heat — keeping air quality high without losing what you paid to condition.
Our Services
Passive House Design-Build
Full-service design and construction to Passive House standard — energy modeled, third-party verified, and built by a dual-certified team.
Custom Home Construction
Comprehensive general contracting for custom homes. High-performance building science applied to every project, regardless of certification path.
Design-Build
One team from sketch to structure. We combine architectural design and construction management to streamline your project and protect your budget.
Passive House Remodels & Retrofits
Bring your existing home up to high-performance standards. Deep energy retrofits, envelope upgrades, and EnerPHit-path improvements for Montana homes.
Let's talk about your project.
Mafic works with a limited number of clients each year so every project gets Stefan's direct involvement. The earlier we connect, the better we can serve your timeline.
We serve Bozeman, Gallatin Valley, and surrounding Montana communities.