Ontario's prefab backyard guest house ADU
LOFT
LOFT
A two-storey backyard guest house ADU with full living, kitchen and dining on the main floor — two private bedrooms with generous closets tucked into the loft above. 1,352 sq ft that feel considerably larger than the footprint.
Starting at:
$180k
(Essentials)
GROSS AREA
1,352
SQ FT
LIVING AREA
788
SQ FT
BEDROOM
2
LOFT LEVEL
BATHROOM
1
Net Zero Ready label applies to Complete Turnkey builds only. Essentials packages are engineered to the same performance standard.
OVERVIEW
The Backyard Guest House ADU That Lives Up
The Backyard Guest House ADU That Lives Up
A purpose-built backyard guest house with full living, kitchen and dining on the main floor and two private bedrooms above. Open volumes make 1,352 sq ft feel considerably larger — ideal for extended family, long-term guests, or rental income.
Best suited for: Long-term guests or extended family · Rental income on your property · Young adult children returning home · Multigenerational households wanting privacy · Home office + guest suite combo
Takes 30 seconds • No commitment
Ready now?
FLOOR PLAN
Loft Backyard Guest House ADU — Floor Plan & Layout
Loft Backyard Guest House ADU — Floor Plan & Layout
←
Main Floor
Loft Level
→
See Main Floor
←
→
See Loft Level
Main Floor
ROOM SUMMARY
Main Floor — Living Spaces
Living Room 166 sq ft
Kitchen 112 sq ft
Dining 111 sq ft
Main Floor — Utility
Bathroom 37 sq ft
Mechanical Room 31 sq ft
Loft Level — Private Spaces
Bedroom I 82 sq ft
Bedroom II 82 sq ft
Closet I 30 sq ft
Closet II 30 sq ft
Total Livable Area 787 sq ft
The Loft's two-storey layout gives Ontario homeowners a full two-bedroom backyard guest house in a footprint that fits standard urban and suburban lots — without sacrificing ceiling height, storage, or livability on either floor.
Takes 30 seconds • No commitment
BIRDSNEST
Why the Loft Works as a Detached Backyard Guest House
Why the Loft Works as a Detached Backyard Guest House
Two full storeys — bigger than it looks from the street
Two full storeys — bigger than it looks from the street
The open volume through the main floor reads as significantly more space than 787 sq ft suggests. A vaulted loft ceiling and open-plan living create the feel of a much larger home.
Vaulted loft bedrooms — privacy built into the structure
Vaulted loft bedrooms — privacy built into the structure
Loft layouts command top-tier short-term rental rates. The architectural character is a feature renters actively seek — and pay for. Two bedrooms on a separate level adds privacy that photographs well and rents better.
Storage that actually delivers in a two-bedroom guest house
Storage that actually delivers in a two-bedroom guest house
Both loft bedrooms include dedicated closets — 30 sq ft each. A differentiator in compact builds where storage is usually the first thing sacrificed.
Performs like a much larger home — built to Passivhaus-level specs
Performs like a much larger home — built to Passivhaus-level specs
787 sq ft with defined living and sleeping zones is a genuinely livable home. The largest model in the lineup for owners who plan to move in themselves and rent the main house.
OVERVIEW
Performs like a much larger home — built to Passivhaus-level specs
Performs like a much larger home — built to Passivhaus-level specs
One 15-minute call to confirm your lot, your timeline, and your next steps. No pressure. No obligations.
Takes 30 seconds • No commitment
I Know What I Want
PICK YOUR STARTING POINT
Choose Your Loft Backyard Guest House Package
Choose Your Loft Backyard Guest House Package
Every package is built to Passive House-level specs. The difference is how much Quantum handles for you.
30-day superstructure delivery
Essentials Package
Essentials Package
Quantum manufactures, delivers, and installs the complete building envelope. You take it from there — with everything you need to hand off confidently to your own trades.
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QUANTUM PROVIDES:
PHI-certified panels delivered + installed
Foundation + slab (no geo-tech, no site survey)
Complete high-performance thermal envelope
Blower door test + airtightness sign-off
Thorough completion report
QC quality assurance checklist
Wall care guide for your trades
Most hands-off
Complete Turnkey
Complete Turnkey
Quantum acts as your General Contractor from first conversation to final walkthrough. Every trade. Every permit. Every stage. You decide to build — we handle everything that comes after.
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QUANTUM PROVIDES
PHI-certified panels + complete envelope
Foundation + slab (Includes geo-tech and site survey)
All mechanical systems — HVAC, electrical, plumbing
Complete interior finishes — drywall, flooring, paint, trim
Cabinetry, countertops + fixtures throughout
Every trade coordinated by Quantum
Final walkthrough + handover
Want Quantum's process and quality assurance without Quantum's crew?
Want Quantum's process and quality assurance without Quantum's crew?
Add the PM Package ($5,000) — material takeoff, QC checklist, timeline and permit guidance — or the PM Service ($15,000) — Quantum supports you finding and managing your local trades of choice. Available on Essentials package.
What's Included in Every Loft Backyard Guest House ADU
What's Included in Every Loft Backyard Guest House ADU
This Model Includes:
This Model Includes:
Duxton Triple-Pane Windows
No drafts. No cold spots. Quiet, stable interiors.
PHI-tested fiberglass casement windows designed for cold climates. Standard, not an upgrade.
In-Floor Heated Bathroom Tile
Warm floors first step out of the shower. Every morning.
Electric in-floor heating beneath ceramic tile — adding comfort where you notice it most.
All-Electric. One Bill.
No propane. No gas. No split systems.
Electric hot water, heating, and cooling. One system aligned with Net-Zero Ready targets.
ERV — Energy Recovery Ventilator
Fresh air. No heat loss.
Continuous fresh air exchange with heat recovery. Quiet, efficient, always running in the background.
Ductless Mini-Split Heat Pump
No furnace. No ductwork. No propane. Ever.
One quiet heat pump does all the work. No fossil fuels, no maintenance contracts.
PHI-Certified Cold-Climate Panels
PHI-certified cold-climate panels. Proven. Built to perform.
The panels are PHI-certified by the Passive House Institute — third-party verified for cold climates.
Standard exclusions — always told upfront:
Standard exclusions — always told upfront:
Site preparation · Foundation engineering · Service hookups (water, sewer, electrical to site) · Geotechnical work
"We walk you through what's outside before you sign. That conversation is part of the first call."
OTHER HOMES PEOPLE ARE EXPLORING
Similar Homes Worth Comparing
Similar Homes Worth Comparing
If you're looking at a home around 788 sq ft, these models are worth a look. All built with PHI-certified panels and delivered Net Zero Ready.
Kin
2 Bed ㆍ 1 Bath ㆍ 698 SQ FT.
Our most versatile layout — ideal for families, multigenerational living, or maximizing long-term value.
settings
Starting At
$164 K
BirdNest
1 Bed ㆍ 1 Bath ㆍ 546 SQ FT.
A fully accessible home designed for comfort, independence, and long-term living — without compromise.
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Starting At
$157 K
Grange
2 Bed ㆍ 1 Bath ㆍ 672 SQ FT.
A balanced two-bedroom layout with indoor-outdoor connection — ideal for everyday living or hosting.
settings
Starting At
$166 K
Build Your Backyard Guest House Right. Book a 15-Minute Call.
Build Your Backyard Guest House Right. Book a 15-Minute Call.
Free 15-minute call. No commitment. A straight conversation about your property, your goals, and whether the Loft backyard guest house ADU is the right move.
Takes 30 seconds • No commitment
I'm Ready now,
Net Zero Ready label applies to Complete Turnkey builds only. Essentials packages are engineered to the same performance standard.
(705) 286-0019
Info@quantumpassivhaus.com
Info@quantumpassivhaus.com
QuantumPassivhaus.com
QuantumPassivhaus.com
What Quantum Homeowners Are Saying...
What Quantum Homeowners Are Saying...
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We lose power often where we live, but the house holds its temperature so well that we don’t have to worry. Even during extreme heat, without air conditioning, the house stayed comfortable.
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Gail & Mike
Quantum Homeowner
The build process was surprisingly efficient. Seeing the panels come together so quickly, and being enclosed early, gave us confidence. Even during storms and power outages, the house holds its heat and stays comfortable
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Cathy and John
Quantum Homeowner
Things didn’t always go as planned, but we always felt they had our backs. Whether resourcing alternate materials, working with subcontractors, or taking on more work, the whole team was talented and friendly.
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Marci & Alan
Quantum Homeowner
From a cost perspective, it was basically the same as building a traditional house at the time, but the efficiency is far better. Everything here is electric, and we only have one bill. In the winter it’s around $250 a month, and in the summer closer to $125—and that includes the spa. Before, we were paying thousands a year in propane alone.
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Gerry & Hilde
Quantum Homeowner
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