When you’re shopping around for a home or apartment—especially in areas with a lot of older housing stock—properties built in the 1990s often strike a balance between “not too old” and “not quite modern.” But like anything with a few decades behind it, there are things you’ll want to look out for. The 90s had their fair share of design trends, materials, and construction methods—some that aged well, and others… not so much.
Here’s a quick rundown of what to know when considering a 90s-built home or apartment.
1. Poly-B Plumbing (Polybutylene)
Ah yes, Poly-B—the infamous grey pipes hiding behind many 90s walls.
What is it?
Poly-B (short for polybutylene) was a popular plumbing material used from the late 70s through the mid-90s. It was affordable and easy to install—but not very durable long-term.
Why it matters:
Over time, Poly-B becomes brittle and prone to cracking or leaking, especially when exposed to chlorine in municipal water. While it might still be functioning in some homes, insurance companies are increasingly wary of it—some won’t insure homes with active Poly-B piping without replacement.
What to look for:
Check under sinks or around the water heater for gray plastic piping. If you’re not sure, get a licensed plumber or home inspector to confirm.
Pro tip:
Replacing Poly-B with PEX or copper can cost a few thousand dollars but adds serious value (and peace of mind).
2. Post-Tension Cables
Most common in apartment buildings and some townhomes/condos with concrete slabs.
What is it?
Post-tension cables are steel cables inside concrete slabs that are tightened after the concrete is poured. They add strength to thinner slabs and are a key part of the structure in many 90s buildings.
Why it matters:
Drilling or cutting into a post-tension slab without the right equipment or permits is a major no-no—it can be dangerous and extremely expensive to fix if something goes wrong.
What to look for:
Most condos or apartments with post-tension will have a warning stamped on the electrical panel or inside a utility room. The MLS and condo documents will state if the building has post-tension.
Pro tip:
If you plan any renos that involve the floors (like adding plumbing, drilling into concrete, etc.), make sure you get the green light from an engineer or building authority.
3. Copper Piping
Now for something a bit more reassuring.
What is it?
Copper piping has been a gold standard in plumbing for decades. Many 90s homes feature copper, especially toward the later part of the decade as Poly-B fell out of favor.
Why it matters:
Copper is durable, long-lasting, and usually well-regarded by home inspectors. It’s also more resistant to bacteria compared to plastic piping.
What to look for:
Shiny (or sometimes greenish) metal pipes under sinks or around water tanks are a good sign you’ve got copper. It’s especially common in higher-end 90s builds.
Pro tip:
Still, check for corrosion or signs of pinhole leaks—especially if the water has a high mineral content. Water softeners can help extend the life of copper pipes.
4. Aluminum Wiring
This one’s a bit trickier, though less common in 90s homes. Aluminum wiring peaked in the 60s and 70s, but in rare cases, leftover supplies were used into the early 80s or even trickled into some early 90s builds in certain regions.
What is it?
Aluminum wiring was used as a cheaper alternative to copper for a while. The issue is, it expands and contracts more than copper, which can lead to loose connections, overheating, or even fire hazards.
Why it matters:
Insurance companies often flag aluminum wiring. If it hasn’t been updated or maintained properly (through a method called "pigtailing" with copper at outlets), it can be a costly and safety-sensitive fix.
What to look for:
Have an electrician check if you're unsure—it’s not always visible without removing outlet covers. A home inspection report should catch it, too.
Pro tip:
If aluminum is confirmed, ask about mitigation work (like pigtailing or full rewiring) and factor that into your budget.
5. Preserved Wood Foundations (PWF)
This one throws a lot of people off—yes, some homes are built on wooden foundations!
What is it?
A Preserved Wood Foundation (PWF) is a type of foundation system made from pressure-treated lumber, designed to resist moisture and rot. It’s been around since the 60s but became more common in prairie provinces during the 80s and 90s as a cost-effective alternative to concrete.
Why it matters:
PWFs can perform well when installed properly—but they require flawless drainage and waterproofing. If moisture builds up or grading isn’t right, the foundation can start to rot, shift, or cause major structural issues. Some buyers (and even some lenders) can be hesitant about PWFs due to longevity concerns.
What to look for:
Check the listing or ask your home inspector if the foundation is wood or concrete. If it’s a PWF, make sure there’s documentation showing it was engineered and properly permitted at the time of build.
Pro tip:
Homes with wood foundations can still be great, but make sure to get a thorough inspection and look at drainage around the home. Also, talk to your mortgage broker ahead of time—some lenders want extra due diligence before approving financing on PWF properties.
Conclusion:
Homes and apartments from the 90s can offer great layouts, mature neighborhoods, and solid construction—but they do come with quirks. A thorough home inspection (and sometimes a plumbing, electrical, or structural specialist) can save you from unexpected costs or safety issues down the road.
That said—none of this is meant to scare you away from homeownership. It’s just about being informed. The more you know going in, the better decisions you can make.
It’s also worth remembering that at one point or another, everything listed above was considered “up to code.” Like most things in life, building practices and safety standards evolve. What was standard in the 90s may not meet today’s expectations—but that doesn’t mean the home isn’t livable or worth buying. It just means you may need to budget for updates or keep an eye on specific systems.
One thing that is crucial? Getting the right home insurance. Many insurers will ask about things like Poly-B plumbing, aluminum wiring, or wood foundations—and in some cases, may charge more or even deny coverage without upgrades or mitigation in place. Knowing what’s in the walls (and under the floors) helps you avoid surprises after you move in.
Whether you’re buying to live in, rent out, or flip, understanding what’s behind the walls is just as important as what’s in the listing photos.
Want help navigating older homes in your area or have questions about what to look for? Feel free to reach out, I’m always happy to help break things down.
