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Ducted Heat Pump Systems
For homeowners who want quiet, whole-home comfort with minimal visual impact. We design air-handler locations, supply and return paths, filter access, and diffuser placement around the remodel’s framing and finishes.
Bay Area Residential HVAC Design-Build
HVAC for Home Remodels & Additions
HVAC Designed Around Your Remodel—Not Added After the Fact.
A remodel changes more than finishes. New rooms, altered layouts, opened ceilings, upgraded insulation, and tighter construction all change how your home should be heated, cooled, and ventilated. 3rdGen designs and installs integrated HVAC systems for major Bay Area renovations, additions, and high-performance homes.
We coordinate with your architect, designer, and builder to place equipment, routes, returns, grilles, and fresh-air ventilation before the walls are closed—so the finished home feels intentional, comfortable, and clean.
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Strategy
A New Layout Requires a New HVAC Strategy
Many older Bay Area homes were never designed for modern comfort. Rooms run hot or cold, returns are poorly located, ductwork consumes valuable space, and existing systems may no longer match the home after an addition or renovation.
The right time to solve those issues is during design and framing—not after drywall, cabinetry, and finish work are complete.
We evaluate the new floor plan, existing conditions, architectural priorities, and construction sequence to develop a system that works with the remodel.
What changes in a remodel
What we design around it
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Added or reconfigured rooms
Correct zoning and equipment capacity
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Open ceilings or exposed beams
Discreet routing and grille placement
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New windows and insulation
Updated heating and cooling needs
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Tighter building envelope
Ventilation and filtration strategy
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Limited mechanical space
Equipment location and service access
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Historic or older-home constraints
Low-impact distribution options
Systems
Mechanical Systems Built Into the Project
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02
Ductless & Multi-Zone Systems
A strong fit where duct routing is limited, additions need independent comfort, or the home benefits from room-by-room zoning. Wall-mounted units, ceiling cassettes, and concealed ducted zones can all be considered based on the architecture.
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03
Home Additions
New square footage may need a dedicated system, an expanded whole-home strategy, or a separate zoned solution. We determine the right approach rather than tying new space into an already strained system. If the ADU is the project, use ADU HVAC.
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04
Ventilation, Filtration & Indoor Air Quality
As a remodel tightens the building enclosure, fresh-air strategy matters. We can incorporate ERVs, balanced ventilation, upgraded filtration, and kitchen and bath exhaust coordination for healthier, more resilient indoor air.
Explore Ventilation
Process
The Earlier We Coordinate, the Better the Result
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01
Review the plans and project goals
We review the architectural set, existing conditions, comfort concerns, mechanical-space options, and construction schedule.
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02
Develop the system approach
We recommend a clear best-fit system—ducted, ductless, or hybrid—along with zoning, equipment locations, ventilation needs, and major routing considerations.
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03
Coordinate with the project team
We work through framing, structural, electrical, plumbing, cabinetry, ceiling, and access conflicts before they become expensive field changes.
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Install during rough-in and finish phases
The system is installed in sequence with the build: rough-in while the structure is open, then trim, startup, and commissioning as the project approaches completion.
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Commission the completed system
We verify operation, controls, airflow, and homeowner handoff so the system is ready to perform from move-in.
Coordination
Comfort Is in the Coordination
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Mechanical-room planning
Equipment needs proper clearance, drainage, filtration access, and future serviceability. We help establish that space early.
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Duct and lineset routing
We coordinate routes through joists, soffits, crawlspaces, attics, and wall cavities while protecting ceiling heights and architectural intent.
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Supply, return, and grille placement
Air needs a path back—not just a supply register. We plan locations that support balanced airflow without compromising the room.
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Noise control
Equipment selection, duct sizing, return design, and diffuser selection all affect how quiet the house feels.
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Electrical and condensate coordination
Heat-pump power requirements, disconnects, condensate drainage, and exterior equipment placement are addressed as part of the construction coordination.
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Finish quality
We plan visible components—linear diffusers, ceiling grilles, wall heads, controls, and exterior line-hide—to fit the finished home.
Best fit
Bring Us In When the Remodel Is Becoming Real
The earlier mechanical decisions are made, the more options the project retains for performance, appearance, and cost control.
- Whole-home renovations
- Major kitchen, living-area, or primary-suite remodels
- Home additions
- Older homes with limited or failing HVAC
- Furnace-to-heat-pump conversions
Remodels that use Mitsubishi equipment are designed and installed as Mitsubishi heat-pump systems by a Diamond Contractor — not as a catalog add-on after finishes are chosen.
The 3RDGEN difference
Designed Before It’s Installed
A new HVAC system should be based on what your home actually needs, not simply the size of the equipment that happened to be there before.
01Manual J
Determine what the home needs
We evaluate how your home gains and loses heat so the system matches the house, not a rule of thumb.
02Manual S
Select equipment that matches
We choose heating and cooling equipment that fits those needs without oversizing.
03Manual D
Plan airflow and room comfort
We plan how air moves through the home so rooms feel balanced and comfortable.
04Startup & testing
Install, start up, and test
We install the system, start it up, and verify it is working the way it should before we call the job finished.
You do not need to become an HVAC expert. That is our job. We use the technical work to give you a better finished system.
How We Design SystemsOur Field Projects
Real Bay Area homes, engineered and installed.
How it goes
A clear path from first question to finished system
One team from the first call to the last: a trained, tested system, not a project that gets handed off three times along the way.
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01 Tell us what you’re planning
Three questions in the form, or a phone call. You tell us the house and the goal; we tell you whether we are the right shop for it.
~40 seconds
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02 We review the home and project
A site visit with the person who will design the system: ducts, panel, equipment locations, and the rooms that never feel right.
60-90 min
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03 Receive a recommendation and proposal
A written scope: equipment, capacity, distribution, electrical work, and what is included, in plain language you can compare against other bids.
Within 5 days
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04 Permitting and installation
We handle permits, Title 24, and inspections, and coordinate with your electrician so no one is waiting on anyone.
2-5 days on site
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05 Startup and final testing
We start the system, verify airflow and performance, register the warranty, and walk you through operating it.
Same week
FAQ
Common Questions
Common questions on remodel HVAC coordination.
When should HVAC be involved in a remodel?
As early as possible — ideally during design development, before framing and finish decisions lock in. Moving a chase, soffit, or equipment room after drywall is expensive. Early mechanical input protects routing, access, and architectural intent.
Do you work with architects, designers, and GCs?
Yes. Many remodel scopes are architect-led or builder-led. We coordinate equipment placement, duct and lineset routes, ventilation, electrical needs, and sequencing with your project team so conflicts get solved before walls close.
Is this the same as full-system HVAC replacement?
No. This page is for remodels and additions where HVAC has to integrate with the construction project. If the driver is an aging system and a major remodel is not part of the job, use Full-System HVAC Replacement.
What if I already know I want a heat pump?
If electrification or a furnace-to-heat-pump conversion is the main decision and a remodel is not driving the scope, use Heat Pump Installation. If the heat pump is part of a remodel or addition, stay here — we still design the system around the project.
Is this for ground-up new construction?
No. New homes belong on HVAC for New Construction. Accessory dwellings, garage conversions, and JADUs belong on ADU HVAC. This page covers renovations and additions in an existing home.
Do you offer standalone Manual J reports without installation?
Our focus is design-build. Load calculations support systems we install. For formal standalone design/load-calculation scope, see Manual J Load Calculations — and expect a project-tied path, not a cheap report-for-hire shop.
Who handles permits and Title 24?
We do, as part of the mechanical scope. Permits, Title 24, and inspections are coordinated with the remodel schedule — not left as a surprise at the end.
Do you service what you install?
Startup, handoff, and warranty support on what we design and install, yes. We are not a repair or emergency dispatch company for unrelated breakdowns.
Can a heat pump replace my furnace?
In most homes, yes. Whether your home has existing ducts or not, we’ll help determine the right approach.
Do I need to know whether I want ducted or ductless?
No. We evaluate the home and recommend the approach. You do not need to become an HVAC expert. That is our job.
What happens after I submit the project form?
We review the home and the project, then send a recommendation with scope and pricing: what we recommend, why, and what it includes.
How long does a typical installation take?
Most straightforward replacements take a few days on site. Remodels, ductwork changes, and new construction follow the project schedule. We confirm timing once we review the home and scope.
Project Inquiry
Inquiry Sent
Thanks — your project details are on their way to 3rdGen. We’ll review them and follow up about the next step.