What would be the best (cheapest) HVAC system for a duplex conversion type project with the goal of having independent climate controls in each unit? 2 furnaces and 2 AC's? High velocity ductless system? Ducted heatpump system?

Hi Daniel, I actually have an HVAC business and might be able to give you some advice. What style of house is it? Up down duplex? What is in there currently and how old? In ground basement or fully above ground?

@Jaydon H. Any Canadian attic east/ north of lower mainland will be -20*C multiple times, most of which that will last weeks in a row, each year. Did I misunderstand your suggestion that this was completely fine for all of Canada?

@Jaydon H. Power eng don’t really do much of forces along beams etc, mainly fluid and gas dynamics. Though I did teach that stuff long ago. We fall somewhere between sanitation engineer and P Eng. right about beside hvac techs who would install a furnace/ ac setup in an attic @ -20C. Take care.

@Jaydon H. In order to install hvac in an attic, anywhere between approximately Coquitlam to PEI, you’d need to ensure the space was conditioned. Meaning, you’d have to insulate your rafters (spray foam would be easiest). After that, you’d need to ensure your soffit venting was eliminated, along with all roof vents. Then you’d want to budget for providing minimum service to condition that extra “interior” square footage. So you’d be increasing your hvac and ac capacity along with moving it up to your now conditioned attic space. Depending on the age of the home, if you’re dealing with stick built rafters, you would be looking at some fairly significant cost to reinforce to ensure you didn’t get sag that would be cracking your drywall on the ceiling. And then there’s the cost of insulated ducting which isn’t terribly efficient wrt r value. Without completing all of the above, you’d be looking at significant condensation leading to a mold concern, stains on your ceiling, replacing ceiling and ceiling insulation within a few years. But please, do elaborate on why in your vast experience and knowledge mounting an hvac system in your attic is a remotely good idea in any part of Canada that experiences winter (below freezing). The problem with measuring dicks on the internet jordan is that you’ll always find a bigger dick. I’m a power engineer who’s designed, and trouble shooted systems large enough for oilfield facilities. You’re wrong. Carry on.

@Jaydon H. That assumption would be false Jaydon. This doesn’t even meet code for the vast majority of Canada. Carry on.

@Jaydon H. The lower mainland makes up less than 1% of Canada’s land mass. Carry on.

@Jaydon H. Attic mount definitely doesn’t work in the majority of Canada.

@Daniel Rosa If this is up down, easiest by far is elec baseboard down and hvac for up. Otherwise you’ll likely need separate ducting, separate sources, no co-mingling. That said, elec baseboard is expensive to run. But they’re bulletproof. Essentially zero maintenance for 40 years.

I never once said anything about a furnace in a -20 attic. Excellent attempt at trying to “prove me wrong again” but that was a swing and a miss. Your an angry engineer aren’t you, go for a walk Fred.

@Daniel Rosa I have a mini split setup in my duplex. Each room has individual controls . Backup baseboards also but not primary heating and cooling. The mini split systems run i believe 3 -5k depending on brand.

Best HVAC for duplex for independent controlls?Best HVAC for duplex for independent controlls?

Back

Resources & Media

Resource Hub Bookstore Blog Guides Pro-Exclusives PRO Podcasts Pro Partnerships Property Management Toolkit

Events & Training

BPCON2025 Webinars Upcoming Events Free Courses

Strategies

How to Manage Your Rental Property How to Operate a Short-Term Rental How to Passively Invest in Real Estate How to House Hack How Does the BRRRR Method Work How to Flip a House How to Invest in Commercial Real Estate How to Invest in Real Estate How to Invest in Multifamily Real Estate How to Build Wealth

The BiggerPockets Conference

This is your chance to learn from the best, network with the best, and become one of the best in the game.

Discover BPCON2025

The Podcast Investors Trust

No fluff. Just deals, strategies, and lessons from the front lines of today's market.

Listen Now

Back

Pick Markets

Market Finder - NEW PRO Picking a Market Workshop PRO Picking a Market Worksheet Top 100 Cash Flow Markets Market Insights - Sunbelt Region

Market finder

Pinpoint the best real estate market for your specific goals with expert recommendations and real-time data on appreciation, affordability, rent-to-price ratio, and more.

Pick Markets

Pro membership

Get unlimited access to tools and resources that make it easier to find, analyze, and manage deals with confidence!

Upgrade to Pro

Back

Find Deals

BiggerDeals NEW Off-Market Deal finding PRO Real Estate Syndications Investor-Friendly Agents Find Foreclosures Community Listings (FSBO) Business Directory

NEW! Find Cash-Flowing Deals Fast

Search nationwide listings with built-in cash flow analysis.

Find Deals

Invelo - off market deals

Scale your portfolio with off-market deals.

Explore Now

Back

Calculators

Rental Property Calculator PRO Rehab Estimator PRO Rent Estimator PRO BRRRR PRO Fix & Flip PRO Short-Term Rental PRO Sell vs. Keep PRO Landlord Insurance Calculator by Steadily All Calculators

Rental property calculator

Is it a good deal? Run your numbers like a pro with this simple yet powerful calculator.

Run the Numbers

Rent estimator

Understand how much rental income you can expect based on recent reports and data for your specific property.

Run Report

Back

Manage Properties

Managing Properties 101 Find a Property Manager RentRedi Property Management Software PRO Baselane Automated Bookkeeping & Banking PRO Property Management Tools Ask a Management Question Finding Tenants Screening Tenants PRO Leases + Landlord Forms PRO Property Insurance Property Maintenance / Rehab PRO

Property management software

Manage tenants, tasks, and your entire portfolio with one simple tool.

Activate Now

Property manager finder

Find reliable property management partnerships that last.

Find a Property Manager

Back

Plans & Pricing

Pro Membership Business Membership

Try PRO for 7 days completly free

Avoid mistakes and make informed decisions with Pro.

Start Free Trial

Grow your business

Promote your business on BiggerPockets and make quality connections with the right investors.

Sign Up Now

Back

For You

Newest Unanswered My Discussions Followed Discussions Followed Categories Followed Locations Followed People

General Real Estate

General Real Estate Investing Starting Out Deal Analysis Buying & Selling Business & Marketing Landlording Property Management Reviews & Feedback

Real Estate Strategies

House Hacking BRRRR Short-Term Rentals Mid-Term Rentals Multi-Family Fix & Flip Other Strategies

Finance & Financing

Lending Creative Finance Personal Finance Taxes & Legal Issues

News & Announcements

Official Site Announcements Market Trends & Data Real Estate News & Current Events Pro Exclusive Area PRO

Events & Networking

Events & Meetups Classifieds

Back

All Books

Best Sellers Browse All New Books & Pre-Orders Bundle & Save Books for Beginners

Unlock hidden potential in every property and maximize returns

This is your creative breakthrough guide to escaping investment paralysis and unlocking hidden profit in any market.

Pre-order now

Build a Cash-Flowing Glamping Business with High Equity Upside

Whether you're starting from scratch or expanding existing hospitality operations, learn the practical frameworks needed to capitalize on the growing demand for upscale outdoor experiences.

Learn More

Best HVAC for duplex for independent controlls?

Most Popular Reply