Garage Conversion: Renovate What You've Got or Start Fresh?
So, you've got a garage here in Portland and you're kicking around the idea of turning it into an ADU. Smart move, truly. It's a fantastic way to boost your property's value and snag some extra living space. But right off the bat, you're hit with a pretty big question: do you work with the structure that's already there, or do you just tear it down and build something completely new? I've seen both approaches play out countless times over the years, and honestly, each one comes with its own set of headaches and perks. Let's dig in.
Option 1: Sprucing Up Your Existing Garage Structure
This is usually the first thing that pops into people's heads. You've already got walls, a roof, a foundation – why not just give it an upgrade? Sounds simpler, right? Sometimes it is, sometimes it's really not. Here's what I've learned.
Cost
At first glance, renovating an existing structure often looks cheaper on paper. You're reusing a bunch of materials, which should save you some cash on demolition and certain new construction costs. But hold on a minute, this is where you need to be extra careful. You're dealing with an older building that wasn't designed to meet today's residential codes. You'll almost certainly have to upgrade the foundation, especially if it's just a slab that was never meant for people to live on. You'll need to add insulation (and let's be real, Portland's weather really demands good insulation!), new windows, doors, plumbing, electrical, and HVAC. A lot of the time, the roof structure needs reinforcing or even replacing to handle snow loads or if you want to add a second story. Sometimes, whatever you save by skipping demolition, you end up spending on getting an old structure up to snuff. It's kind of like peeling an onion; you might just find more layers of cost once you start opening up those walls.
Durability & Maintenance
How long a renovated garage ADU really lasts depends a lot on your garage's starting condition and how thoroughly you do the renovation. If your garage has a solid foundation and decent "bones," you're in a pretty good spot. But if it's an older building with a failing foundation, dry rot, or a compromised roof, you're basically building on a wobbly base. You might fix the obvious problems, but sometimes hidden issues can lead to more maintenance down the road. You're often working with older materials and construction methods, which might not be as tough or energy-efficient as something brand new.
Appearance
Renovating can sometimes tie your hands when it comes to design. You're stuck working within an existing footprint, and often with existing wall heights and rooflines. While you can definitely make it look great, getting that truly modern or custom vibe can be tougher. It often ends up looking like, well, a converted garage – which isn't always a bad thing, but it might not blend perfectly with your main house or neighborhood if that's what you're aiming for. Just think about those older garages in places like Southeast Portland, with their low eaves and simple construction; turning those into bright, airy living spaces? That can be a real design puzzle.
Option 2: Knock Down the Garage and Build New
This route means tearing down the old garage completely and putting up a brand-new ADU in its place. It sounds more drastic, I know, but it often brings some serious benefits.
Cost
Yes, you'll definitely have demolition costs. But once that's out of the way, you're building on a clean slate. This means you can design and build to modern codes right from day one. You won't be trying to cram plumbing or electrical into existing walls, or shoring up a questionable foundation. While the initial cost might seem higher because of demolition and all-new materials, you often find cost efficiencies during the actual construction process since everything is new and designed to work together. You also avoid those nasty surprises that tend to pop up when you're renovating old structures, which can totally blow budgets. Sometimes, the