Licensed & Insured · Serving the GTA
ADU & Garden Suite Construction in the GTA
Add a self-contained living unit to your property — a garden suite, laneway home, or legal basement apartment — designed, permitted, and built by one team.
- Garden suites, laneway homes & basement apartments
- Rental income & multi-generational living
- Zoning review, permits & construction under one contract
★★★★★ 5.0 from 100+ Google reviews · Free itemized quotes
Free ADU Feasibility Assessment
Find out what your property allows
GTA ADU & Garden Suite Builders
Y2 Design & Build designs and builds additional dwelling units across Toronto and the GTA — from detached garden suites to legal basement apartments. We handle the zoning review, drawings, permits, and construction, and we build to the fire-separation, sound, and egress standards a legal second unit requires.
- One project manager assigned to your job from the first site visit through handover — you're never chasing down different trades for answers.
- In-house design support and 3D visuals when your project would benefit from seeing the space before construction starts.
- We pull and manage every required permit ourselves — Toronto Building, ESA, TSSA, and local municipal sign-offs.
- Materials sourced through our own wholesale suppliers, so you get better pricing without the retail markup.
Get Started in 3 Simple Steps
From first call to final walkthrough — here's exactly how it works.
Book Your Free Consultation
Call or request a quote online. We visit your home, take measurements, and listen to what you want — no pressure, no charge.
Approve Your Fixed-Price Quote
You get a written, itemized quote covering scope, materials, and labour. The price you approve is the price you pay.
We Build. You Move In.
One dedicated project manager runs your renovation on a locked schedule — permits, trades, and cleanup all handled for you.
Why Build an ADU
An ADU turns unused space on your property into long-term value — monthly rental income, a private home for aging parents, or independent space for adult kids. Toronto and most GTA municipalities now actively permit garden and laneway suites.
Rated 5 Stars by GTA Homeowners
Real reviews from real renovation clients across the Greater Toronto Area.
“From the start, my wife and I felt completely at ease working with John and Andy. We couldn't be happier with our new bathrooms — finished exactly on schedule and within budget. The entire experience exceeded our expectations.”
Marc
Markham
“It was so wonderful working with Y2. John was my primary contact and he was AMAZING and so professional. We redid our primary bathroom and flooring — everything was so organized and timely.”
Shararah S.
Markham
“We wanted to update our bathroom with a budget in mind. Y2 listened, started work the next day, and finished in 4 days. We are very pleased and would recommend them.”
Karthi
Pickering
“Jeff from Y2 Design was very helpful throughout the process. The work was done efficiently and effectively. Will highly recommend.”
Smriti
Markham
“They did our flooring for us. Floors look great, and we're really happy!”
Lizzie
Ajax
“Our kitchen was completely outdated and Y2 turned it into something we're actually excited to cook in. The team walked us through every material choice and stuck to the timeline they gave us.”
David T.
Oakville
Feasibility Before You Spend
Not every lot qualifies for a detached suite — setbacks, lot coverage, laneway access, and servicing all matter. We review your property against your municipality's ADU rules first and give you a realistic budget range before any money goes into drawings.
Legal, Safe & Fully Permitted
A legal second unit has real code requirements: fire separation, sound attenuation, independent egress, and proper ventilation. We design and build to those standards and manage every permit and inspection, so your unit is registered and rentable.
Turnkey From Dirt to Keys
One project manager runs the entire build — excavation, foundation, structure, mechanical, and finishes — on a locked schedule. You get a move-in-ready unit with a full closeout package at handover.
Gallery Of Recent Projects
ADU Construction FAQs
Common questions about adu construction projects in the GTA.
Basement ADU conversions typically run $50–$120 per sq ft. Detached garden suites and laneway homes are quoted after a feasibility review — most GTA projects land in the $250,000–$500,000 range all-in, including design, permits, and construction.
Design and permits typically take 3–5 months depending on the municipality. Construction runs roughly 6–10 weeks for basement conversions and 4–8 months for detached garden or laneway suites.
It depends on your lot's zoning, setbacks, servicing, and emergency access. We check all of it as part of a free feasibility assessment before you commit to anything.
Yes — zoning review, architectural drawings, permit applications, and every inspection through to final sign-off are managed by our team.
Get Your Free Renovation Quote
Tell us about your project — or call (647) 507-3639 to talk now.