What is an Upstairs Floor Made Of? (5 Materials You Need to Know)

I once walked into a friend’s house and heard this loud creak upstairs. I joked, “Are you sure you’re not hosting a ghost party up there?” Turns out, it was just the old flooring settling in. That day I realized how much people underestimate what’s really under their feet, especially upstairs. So, what is an upstairs floor made of? Let me share what I’ve learned over years of installing and inspecting floors on the upper levels of homes.

What Is an Upstairs Floor Made Of?

When someone asks me what an upstairs floor is made of, I usually start by clarifying: do you mean the visible surface you walk on or the entire floor structure including support? Because upstairs floors are actually multi-layered systems.

At its core, an upstairs floor consists of:

Subfloor: The sturdy base that supports everything above.
Underlayment: A thin layer that smooths the surface and sometimes adds soundproofing.
Finish flooring: The visible material like hardwood, carpet, tile, or laminate.

What makes upstairs floors different from downstairs? Weight. Upstairs floors carry less load than foundations or ground floors but must be strong enough to prevent bouncy or creaky feelings when walking.

The materials used affect durability, sound transmission, comfort, and budget. Through my experience, I’ve found five key materials that most homeowners deal with or should know about.

1. Plywood Subfloor — The Unsung Hero

Plywood is probably the most common material for the subfloor on upper levels. It’s made by gluing together thin layers of wood veneer with the grain alternating for extra strength. This cross-grain design helps resist warping and keeps the floor flat.

Why Plywood?

I remember working on a renovation where the plywood subfloor was so thin and cheap it felt like walking on a trampoline. The joists underneath were fine, but the subfloor was too flexible. We replaced it with 3/4-inch tongue-and-groove plywood, and suddenly the floor felt solid — no creaks, no bounce.

In that particular job, the family was relieved because their kids used to complain about feeling like they were “bouncing” when running in the hallway upstairs. This made me realize how critical the subfloor thickness and quality are for comfort and longevity.

How strong is plywood?

Typical 3/4-inch plywood can handle around 40 pounds per square foot (psf) live load.

For bedrooms and living rooms, building codes usually require 30-40 psf.
Thickness affects stiffness: thinner plywood under 1/2 inch can cause squeaks or flex.

I’ve seen contractors try to save money by using 1/2-inch plywood or OSB panels as subfloors upstairs. While cheaper at first, this often leads to squeaky floors and customer complaints long-term.

Installation Tips

One tip that has saved me countless callbacks: use tongue-and-groove plywood for subfloors. The interlocking edges reduce movement between sheets which reduces squeaks and gaps.

Also, screw down the plywood properly using a combination of screws and adhesive for best adhesion to joists. Don’t just rely on nails—screws hold better and reduce movement.

Data Backed Insight

According to a report by the APA – The Engineered Wood Association, plywood subfloors with tongue-and-groove edges reduce deflection (floor bounce) by about 20% compared to square-edge panels.

Additionally, studies show that increasing plywood thickness from 1/2 inch to 3/4 inch can increase floor stiffness by 50%, which is noticeable in everyday walking comfort.

2. Oriented Strand Board (OSB) — Budget-Friendly But Tricky

OSB is another popular subfloor option made by compressing wood strands with adhesives. It’s cheaper than plywood but has some downsides.

I once had a client who installed OSB subfloor without sealing it properly. After a heavy rain leaked through the roof, parts of the OSB swelled and warped. Not fun.

Pros and Cons from Experience

Pros: Cheaper than plywood; decent strength; widely available.
Cons: More sensitive to moisture; edges can swell; heavier than plywood.

Thickness Recommendations

OSB usually comes in 7/16 to 3/4 inch thickness. For upstairs floors, I recommend at least 5/8 inch OSB to avoid bounciness. Thicker OSB panels provide better stiffness but cost more.

Moisture Problems

Unlike plywood’s cross-laid veneers, OSB strands absorb water more readily—especially at edges where they are exposed during installation or leaks occur. This leads to swelling and potential structural issues.

I recall one project where OSB panels installed near a bathroom upstairs were exposed to minor leaks due to plumbing issues. The edges swelled up to 1/4 inch causing uneven floors and tile cracks above.

Mitigating Moisture Risks

To reduce the risk of moisture damage:

Seal OSB edges with waterproof coatings before installation.
Avoid storing OSB panels outdoors uncovered.
Install vapor barriers or house wraps below subfloor layers in humid climates.

Inspect plumbing regularly in upper floors to prevent leaks.

Strength Comparison

OSB has comparable strength to plywood in compression tests.
It has lower stiffness, which means more floor bounce if panels are thin.

The cost difference can be around 15-30% less per sheet compared to plywood in many markets.

If you’re working with a tight budget but want decent performance, OSB can be a good choice as long as you take care with moisture control.

3. Engineered Wood Flooring — Beauty Meets Stability

When it comes to finished flooring upstairs, engineered wood is a favorite of mine for mixing looks and performance.

Unlike solid hardwood planks that are all one piece, engineered wood is layers of real wood veneer glued over plywood or high-density fiberboard (HDF). This layered approach reduces expansion and contraction with humidity changes — a big plus upstairs where temperatures vary.

My Take on Engineered Wood

I installed engineered hardwood in my own home about five years ago. It’s held up beautifully with minimal gaps or warping even through seasons with high humidity swings. Plus, it looks just like solid hardwood to guests.

In one job for a client in a coastal area with high humidity levels, we chose engineered wood precisely because solid hardwood would have expanded too much causing buckling.

Construction Details

Most engineered hardwood has 3–10 layers:

Top layer: real hardwood veneer (1-6 mm thick)
Core layers: plywood or HDF layers stacked crosswise for stability

Bottom layer: balancing layer to prevent cupping

This construction method gives it dimensional stability that solid wood lacks.

Installation Methods

You can install engineered wood:

Floating (click-lock system) — easy DIY option floating above underlayment.
Glue-down — adhered directly to subfloor for a more permanent feel.
Nail-down — similar to solid hardwood but requires proper subfloor prep.

Each method has pros and cons depending on your subfloor type and use case.

Durability and Costs

Engineered hardwood hardness depends on species (oak, maple, hickory) and finish type (UV-cured polyurethane is common).

Costs range:

Lower-end: $4-$6 per square foot
Mid-range: $6-$10 per square foot
High-end: $10-$12+ per square foot for exotic species or thick veneers

Durability wise:

Can last 20+ years with proper care
Top veneer thickness determines how many times it can be sanded/refinished (thicker veneers last longer)

Maintenance Tips

Avoid excessive water during cleaning—use damp mop only.
Use felt pads under furniture legs.
Refinish every 7–10 years depending on wear.

4. Carpet — Comfort With Sound Absorption

If you want a soft cozy feel on your upper floors, carpet might be your go-to material. It’s surprisingly common in bedrooms and hallways upstairs for noise reduction and warmth.

What I’ve learned about carpet upstairs:

It cushions footsteps and reduces sound traveling downstairs.
Padding beneath carpet adds extra comfort and insulation.

Maintenance involves regular vacuuming and deep cleaning every year or two.

I once helped a family switch from hardwood upstairs to plush carpet because their kids loved playing on the floor without worrying about bumps. The tradeoff was less durability but more comfort.

Carpet Types

Carpet fibers come from:

Nylon (durable, stain-resistant)
Polyester (soft but less durable)
Wool (natural but expensive)

For busy households upstairs, nylon carpets with quality padding work best.

Costs and Stats:

Average carpet cost ranges from $2 to $7 per square foot including padding.
Carpet absorbs up to 50% more sound than hardwood or laminate floors.

Lifespan varies widely — budget carpets last about 5 years; premium ones can last 10+ years with care.

Sound Absorption

Upstairs noise can be a major annoyance downstairs. Carpets reduce impact noise substantially compared to hard surfaces. In one apartment project I worked on, switching from laminate to carpet upstairs reduced noise complaints by around 40% based on tenant feedback surveys.

Installation Tips

Carpet installation requires proper tack strips around perimeter and stretching tools to avoid wrinkles or bubbling over time.

5. Luxury Vinyl Plank (LVP) — Durable and Stylish

Luxury vinyl plank flooring has grown on me over the years as a top choice for upstairs floors. It mimics wood or stone but handles moisture and wear way better.

I installed LVP in a rental property upstairs where tenants occasionally spilled drinks or brought muddy shoes. The floors cleaned up easily without damage.

Why LVP works upstairs:

Water-resistant or waterproof options prevent damage.

Softer underfoot than tile or hardwood.
Available in many designs that look very realistic.
Easy to install as floating floors or glue-down.

Construction Details

Most LVP consists of four layers:

Wear layer (protects against scratches)
Printed design layer (wood or stone look)

Vinyl core (provides stability)
Backing layer (adds cushioning)

Thickness varies from 2 mm up to over 8 mm thick for luxury lines that feel more solid underfoot.

Longevity & Costs

LVP costs range between $2 and $7 per square foot depending on brand and thickness.

Durability:

Can last 10–20 years with proper care

Wear layers vary from 6 mil (light traffic) up to 20 mil (heavy traffic commercial grade)

Installation Tips

Keep subfloor flat within tolerance (<3/16 inch over 10 feet). Use appropriate underlayment recommended by manufacturer for sound control and cushioning.

Additional Flooring Materials Worth Mentioning Upstairs

While those five are what I encounter most often, here are some other materials you might see upstairs:

Tile Flooring

Rare but possible upstairs — especially bathrooms or laundry rooms. Tile requires strong subflooring and proper waterproofing underneath to prevent cracking or water damage below.

Bamboo Flooring

A sustainable alternative similar in installation to hardwood or engineered wood but slightly more susceptible to moisture damage if not well sealed.

How FloorTally Helps Me With Upstairs Flooring Projects

Estimating flooring costs accurately can be really tricky because prices vary by location, material quality, labor rates, waste factor, and installation method. I’ve tried juggling spreadsheets, multiple quotes from suppliers and contractors—it’s exhausting!

FloorTally simplifies this by consolidating all those variables into one easy-to-use platform. It lets me input:

Square footage
Material types

Local labor rates
Waste percentages (which are crucial because cutting planks always creates waste)

It instantly generates detailed cost estimates helping me create realistic budgets for clients before starting any work—without endless back-and-forth calls or guesswork.

For example, on my last project replacing carpet with engineered wood upstairs, I plugged numbers into FloorTally and saw how changing veneer thickness affected costs by hundreds of dollars immediately. That helped me advise my client effectively without surprises later.

Common Upstairs Flooring Problems & How I Fix Them

Creaking Floors

Cause: Movement between subfloor sheets or loose nails/screws

Fix: Reinforce subfloor attachment; add screws; use construction adhesive when installing new subfloors; add anti-squeak compounds if needed.

Bouncy Floors

Cause: Thin subfloor; wide joist spacing; weak joists

Fix: Increase subfloor thickness; add blocking between joists; sister joists if necessary for strength improvements.

Uneven Floors

Cause: Warped subfloor; uneven joists; water damage swelling OSB/plywood

Fix: Remove damaged sections; shim low spots; use leveling compounds on plywood before finish installation.

Noise Transmission Downstairs

Cause: Hard floor surfaces without sound barriers transmitting impact noise

Fix: Add soundproof underlayment like cork or mass-loaded vinyl under finish flooring; install carpet; seal gaps between floor assemblies.

FAQs About Upstairs Floors From My Experience

Q: Can I install tile flooring upstairs?

A: Yes, but you need a strong subfloor rated for tile loads (e.g., cement backer board over plywood) plus proper waterproofing if near wet areas. Tile adds weight so joist strength matters too.

Q: How thick should my plywood subfloor be upstairs?

A: At least 3/4 inch tongue-and-groove plywood is recommended for stiffness and durability in residential settings.

Q: Is vinyl plank better than hardwood upstairs?

A: Depends on priorities—vinyl plank is more moisture resistant and lower maintenance while engineered hardwood offers natural wood looks and can be refinished if thick enough veneer exists.

Q: What’s the best way to reduce noise from footsteps?

A: Carpet with quality padding works best followed by soundproof underlayments below hard flooring surfaces like engineered wood or vinyl plank.

Final Thoughts From Me About Upstairs Flooring Materials

Choosing an upstairs floor isn’t just about picking something pretty—it’s about balancing strength, sound control, moisture resistance, comfort, and budget practicality.

Over the years, I’ve worked on countless homes where understanding these five key materials—plywood, OSB, engineered wood, carpet, and luxury vinyl plank—made all the difference between happy clients and costly callbacks.

Remember,

the subfloor is your foundation—don’t cut corners there!

Think about noise too—upstairs footsteps matter downstairs more than most expect!

And use tools like FloorTally for quick, accurate budgeting so surprises stay at bay.

If you’re planning an upstairs project, feel free to ask me anything about materials, installation, or troubleshooting—I’m happy to help out!

Ready to tackle your upstairs floor with confidence?