SERVICES · REMODELS & RETROFITS
Turn your existing home into a high-performance one.
You don't need to build new to get the comfort, efficiency, and durability of a Passive House. Mafic brings the same certified expertise to deep energy retrofits and whole-home remodels on existing Montana homes.
COMMON STARTING POINTS
-
Older home, high heating costs
Leaky envelope, inadequate insulation, aging mechanicals. We assess, model, and fix the root causes.
-
Buying a home and planning upgrades
Pre-purchase energy assessment and a phased retrofit plan so improvements happen in the right order.
-
Wanting to reach net zero or EnerPHit
A staged pathway to EnerPHit certification — the Passive House standard for existing buildings.
Montana's housing stock is under-performing. We can fix that.
Most homes in the Gallatin Valley were built well before modern building science. Drafty envelopes, inadequate insulation, and oversized mechanical systems aren't just uncomfortable — they're expensive. A targeted deep energy retrofit can cut heating costs by 60–80% and make your home dramatically more resilient and comfortable.
WHY PASSIVE HOUSE
What we do on a retrofit project
Every project starts with an honest assessment of what your home needs. We don't prescribe the same solution to every house — scope is driven by your goals, budget, and what will have the most impact.
Envelope upgrades
The foundation of any deep retrofit. Reducing heat loss and air leakage.
Continuous exterior insulation
Airtightness detailing & air barrier
Triple-pane window replacement
Thermal bridge elimination
Whole-home remodels
Combining high-performance upgrades with interior renovation work.
Additions with Passive House details
Structural & layout changes
Integrated performance upgrades
Mechanical systems
Right-sizing heating, cooling, and ventilation for a tighter envelope.
ERV/HRV installation
Heat pump heating & cooling
Heat pump water heating
Mechanical system right-sizing
Energy assessment & planning
For homeowners who want a roadmap before committing to scope.
Blower door diagnostic testing
Energy modeling of current home
Phased improvement plan
Incentive & rebate identification
OUR PROCESS
How a retrofit project project works
Retrofits are more complex than new builds — every house is different and the sequencing of improvements matters. We bring a structured approach to what can otherwise become an expensive, piecemeal process.
-
Blower door testing, thermal imaging, and a full review of your existing envelope and mechanical systems.
-
We model your home's current performance and the projected impact of proposed improvements — so you can prioritize by cost-effectiveness.
-
A sequenced improvement plan aligned to your timeline and budget. Some work now, some later — in the right order.
-
Post-retrofit blower door test confirms the improvements. Optional third-party EnerPHit certification available.
CERTIFICATION PATH
EnerPHit: Passive House standard for existing buildings.
EnerPHit is the Passive House Institute's certification for retrofitted buildings. It uses a component-based pathway that acknowledges the constraints of working with an existing structure — giving you a credible, documented performance standard without the impossible constraints of new construction targets.
We can guide your project toward EnerPHit certification, or focus on performance improvements without formal certification — depending on your goals.
STANDARD RETROFIT
Performance
Improvement-focused, no formal standard
Verification
Pre/post blower door test
Best for
Budget-focused or phased improvements
EnerPHit PATH
Performance
Meets PHI component & energy criteria
Verification
Third-party certified & documented
Best for
Maximum resale value, net zero goals
Common questions
Where do you start on an existing home?
1
Always with an honest assessment — blower door testing and energy modeling of the home as-is. That data drives every decision. We don't recommend scope without knowing what will actually move the needle for your specific house.
Can we do the work in phases?
2
Yes, and for most retrofit clients this is the right approach. We build a sequenced plan so improvements happen in the correct order — envelope before mechanicals, for example — and budget is spread over time without undoing earlier work.
What incentives are available for retrofit work?
3
The Inflation Reduction Act includes significant rebates and tax credits for heat pumps, insulation, windows, and other efficiency upgrades. Montana also has utility rebate programs. We identify applicable incentives at the planning stage.
Do we need to move out during construction?
4
It depends on scope. For targeted envelope work or mechanical replacements, most homeowners stay in place. For whole-home remodels, temporary relocation is usually necessary for a portion of the project. We plan around your situation.
Let's look at what your home can become.
Tell us about your home — age, location, what's bothering you about it — and we'll set up a conversation about what's possible.