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EST. 2026 · Knoxville, TN
A window company that acts like a neighbor.

Knoxville Window Replacement. One Price. Good for 90 Days.

Premium vinyl windows. Limited lifetime warranty. One honest number. Take your time.

Get Your Free Quote
✦ · ✦ · ✦
Limited Lifetime Warranty
One Honest Price
Locally Owned
Serving Knoxville & East Tennessee since 2026.
See the work

Real windows. Real homes.

Window installation Window installation Window installation Window installation Window installation Window installation Window installation Window installation Window installation Window installation Window installation Window installation
Our Standards

Three things we don’t budge on.

The mule is stubborn about the right things. We are too.

01
The Price

One Honest Price. Good for 90 Days.

No fake retail prices. No 50% "today only" discounts. No calling your spouse right now. We show up, measure every opening, and hand you a written quote.

02
The Warranty

Lifetime Means Lifetime.

Covers frame, glass, hardware, and our labor — non-prorated, transferable to the next owner, for as long as you own the home.

03
The Install

Installed Once. Installed Right.

Every opening sealed properly. Every trim piece finished. Every warranty registered before we leave.

Our Products

What we install.

Premium vinyl windows built for East Tennessee. Custom-manufactured to your exact openings. Backed for life.

DH

Double-Hung

The classic replacement window for Knoxville homes.

Learn More
CS

Casement

Tightest seal. Best ventilation. Contemporary look.

Learn More
SL

Slider

Wide openings. Simple operation. Modern homes.

Learn More
BB

Bay & Bow

More light. More space. More character.

Learn More
PC

Picture

Maximum light. Zero interruption. Stunning views.

Learn More
PD

Patio Doors

Bring the outside in. Smooth. Energy efficient.

Learn More
Meet the Mule

Local. Independent. Straight-shooting.

Twenty years in sales and operations. Started Stubborn Mule to bring homeowners premium windows without the corporate games.

Read Our Story →
Our Process

Four steps. No games.

Take your time at every step. We’re not going anywhere.

Step 01 — The Visit

Free Consultation

One hour at your home — that’s our cap. We measure every opening and answer your questions, then we’re out. We only stay longer if you ask us to.

Step 02 — The Number

Written Quote

Itemized. Clear. Good for 90 days. Take your time.

Step 03 — The Build

Custom Built

Every window manufactured to your exact opening dimensions. 4-6 weeks.

Step 04 — The Install

Pro Install

Full crew, typically 1-2 days for whole-house. Sealed. Trim finished.

Where We Work

Serving Knoxville and East Tennessee.

From Knoxville to Jefferson City — and everywhere between.

Knoxville & surrounding communities

Not sure if we serve your area? Give us a call — we probably do.
Take Your Time

Bad Windows? Call the Mule.

Whenever you’re ready — tomorrow, next week, next month — we’re here. No pressure, no follow-up spam, no games.

Get Your Free Quote
Our Story

Twenty years chasing the right way to do this.

The story behind the mule. Two paragraphs. Then get your windows.

I spent twenty years in sales and operations — multi-unit franchise ownership, real estate, a tech company I founded and exited, and most recently corporate home improvement. That last chapter is what pushed me to start Stubborn Mule. I watched an entire industry train salespeople to manipulate homeowners into signing tonight, and it wasn’t for me.

That wasn’t the only mistake I watched them make. From the inside I saw bad orders, unnecessary overhead, and headcount they didn’t need — all of it driving the price up, all of it charged to the homeowner. Stubborn Mule is built the opposite way: a new-age company that cares about two things — the customer, and our promise of quality at every angle. Everything else is noise. Your money goes to a local company owned by someone who lives about five miles from you. When something goes wrong, I’m the one you call.

SH
Sam Hollinger Founder & Owner · Stubborn about the right things.
Take Your Time

Ready when you are.

Get a straight quote from a company that shows up when they say they will, does the work right, and stands behind it for life. No pressure, no follow-up spam, no games.

Get Your Free Quote
Ready When You Are

Bad Windows? Call the Mule.

Get your free in-home quote. Written estimate, good for 90 days. No pressure. No games.

Free Quote Request

Tell us about your windows.

Please tell us your name.
We need a number to call you back.
Call the Mule
Or reach us directly

Straight to the point.

HoursMonday – Saturday
8am – 7pm
Service AreaKnoxville, Farragut, Maryville, Oak Ridge, Lenoir City, Jefferson City.

What Happens Next

  1. We call you within 24 business hours (usually much faster).
  2. Your free in-home consultation — capped at one hour. We measure, we answer questions, and we don’t overstay (unless you want us to).
  3. You get an exact written quote, good for 90 days. Zero pressure.
Our Windows

Six window styles. One standard.

Premium vinyl windows built for East Tennessee. Custom-manufactured to your exact openings. Backed for life.

DH

Double-Hung

Two operable sashes. Timeless look. Fits nine out of ten East Tennessee homes without breaking the aesthetic. The de...

Learn More
CS

Casement

Hinged on the side. Cranks open with a single hand. The best window in the category for energy efficiency and unobst...

Learn More
SL

Slider

Horizontal glide. Simple operation. Perfect for contemporary architecture and wider openings. A clean visual li...

Learn More
BB

Bay & Bow

A room-changing architectural feature. Adds interior space, catches light from three angles, and delivers instant cu...

Learn More
PC

Picture

Fixed glass. No moving parts. The strongest energy performance in the vinyl category and an uninterrupted view of wh...

Learn More
PD

Patio Doors

Smooth operation. Energy-efficient glass. Built for Tennessee weather — from Knoxville summers to lake-effect winter...

Learn More
Take Your Time

Not sure which one?

That’s what the style quiz is for. Five questions, and the mule will point you to the right window for your home. 45 seconds. No forms.

Get Your Free Quote
Double-Hung Windows

The classic for Knoxville homes.

Two operable sashes. Timeless look. Fits nine out of ten East Tennessee homes without breaking the aesthetic. The default replacement window for a reason.

What They Are

A double-hung window has two vertically-sliding sashes — both the top and bottom can open independently. It’s the most common residential window design in America for good reason: familiar look, easy to operate, easy to clean from inside the house (both sashes tilt in), and works in almost any architectural style.

Modern vinyl double-hungs are dramatically more efficient than the wood double-hungs they replace. Multi-chamber frames, dual or triple-pane glass, and modern weatherstripping deliver measurable energy savings.

Why Homeowners Choose Them

Double-hung is the right pick when you want a classic look that works with any home style, easy operation for any homeowner, and simple maintenance forever. They’re the standard for a reason — homeowners rarely regret them.

One thing to know: because both sashes slide vertically, the maximum opening is only half the window height. For maximum ventilation you might consider casement instead.

The classic. Timeless look. Easy to clean.
— The Standard Replacement Window
What We Install

The specifics.

Every unit is built to your exact opening dimensions . Here’s what’s inside.

01

Frame & Build

Multi-chamber fusion-welded uPVC reinforced with a K-Beam (Kevlar) core — marketed 5× stronger than steel and 700× warmer than aluminum. Won’t warp, rot, or need paint.

02

Glass & Seal

Double- or triple-pane Low-E with argon (krypton on premium triple). The Super Spacer warm-edge seal runs up to ~16°F warmer at the glass edge than metal spacers.

03

Operation

Both sashes tilt in for cleaning on the Endura-Force balance system — no lubrication, no adjustment. Invisible Tilt hardware (Elements) hides the latches for a clean sash line.

Built

Three ways to spec it.

Every window is custom-built to your exact opening — premium American-made vinyl sold only through installers, never big-box. Good, better, best:

Good

Pro

High-performance value with “practically limitless” customization. A strong, efficient everyday window that still outperforms most of what’s on the market.

Better

Imperial Elite

The premium line — named ENERGY STAR Most Efficient 2025. K-Beam reinforcement with Kevlar and the UltraSmart triple-fin antimicrobial weatherseal.

Best

Elements

The flagship. Industry-best 0.01 cfm air infiltration, ComfortFoam-insulated frame, Super Spacer, and the Dual-Action Invisible Tilt hardware.

Placeholder: which series we lead with as our standard offer is still being finalized — we’ll set that before launch.

Energy & Performance

The numbers.

A double-hung opens to about half its height — plenty for most rooms — and both sashes tilt in so you clean the outside from inside. For maximum airflow, compare casement.

Double-pane · Low-E · argonSuper Spacer warm-edge seal. Our standard package.
U 0.27 · SHGC 0.28
Triple-pane · Ultra-S glassUpgrade for colder rooms and lower bills.
U 0.20 · SHGC 0.24
Triple-pane · Ultimate glassThe best thermal performance we offer.
U 0.17 · SHGC 0.24
Air infiltrationLower is tighter. Elements line.
as low as 0.01 cfm
ENERGY STAR 7.0Qualifying configurations, every U.S. climate zone.
Certified

Placeholder values from our published glass packages — your exact NFRC label (U-factor, SHGC, VT) is confirmed per configuration when we measure. The window carries our Limited Lifetime warranty; your installation carries ours.

Make It Yours

Colors, grids, and glass.

Custom-built means you choose. A sample of what we offer — full menu at your in-home visit.

Interior finishes
Soft-WhiteBeigeMedium OakLight OakBrazilian Cherry
Exterior colors
BlackBronzeForest GreenTerratoneSandstoneRoyal BrownGray+ custom match
Grids & glass
Colonial gridsPrairieFlat / contouredSimulated Divided LiteTriple-paneObscure / privacyTemperedLaminated (sound)
Take Your Time

Ready when you are.

Double-Hung might be the right fit. It might not. Either way, we’d rather have that conversation in person than push you toward a decision on a website.

Get Your Free Quote
Casement Windows

The tightest seal in the vinyl category.

Hinged on the side. Cranks open with a single hand. The best window in the category for energy efficiency and unobstructed views. Built for the way modern homes are designed.

What They Are

A casement window is hinged on one side and cranks outward like a door. That single design choice does a lot of work: because the sash presses tight against the frame when closed, the seal is the tightest of any operable vinyl window.

The result is measurable — better energy efficiency, better weather resistance, better sound insulation than double-hung or slider windows of the same size and glass package.

Why Homeowners Choose Them

Casement windows are the right pick when you want maximum ventilation, minimum obstruction, or top-tier energy performance. They’re a natural fit for kitchens (crank open over the sink), bedrooms, or contemporary homes where clean lines matter.

One thing to know: because they crank outward, they take up outside space when open. If you’ve got a walkway or deck right against the window, that’s a consideration.

Tighter seal. Better ventilation. Cleaner sightlines.
— What the Mule Says About Casements
What We Install

The specifics.

Every unit is built to your exact opening dimensions . Here’s what’s inside.

01

Frame & Build

Same fusion-welded, K-Beam-reinforced uPVC frame as the whole line — rigid, weathertight, and finished to match.

02

The Tightest Seal

Cranks shut against multi-point locking hooks that pull the sash into the frame on all sides. The result is the lowest air infiltration of any operating window we build.

03

Operation

One-hand roto crank with a folding nesting handle that sits flush behind blinds and shades. Sized to meet bedroom egress code.

Built

Three ways to spec it.

Every window is custom-built to your exact opening — premium American-made vinyl sold only through installers, never big-box. Good, better, best:

Good

Pro

High-performance value with “practically limitless” customization. A strong, efficient everyday window that still outperforms most of what’s on the market.

Better

Imperial Elite

The premium line — named ENERGY STAR Most Efficient 2025. K-Beam reinforcement with Kevlar and the UltraSmart triple-fin antimicrobial weatherseal.

Best

Elements

The flagship. Industry-best 0.01 cfm air infiltration, ComfortFoam-insulated frame, Super Spacer, and the Dual-Action Invisible Tilt hardware.

Placeholder: which series we lead with as our standard offer is still being finalized — we’ll set that before launch.

Energy & Performance

The numbers.

A casement seals like a car door and swings fully open, so it ventilates better and leaks less air than any other operating style — ideal over a kitchen sink or anywhere a crank is easier than a lift.

Double-pane · Low-E · argonSuper Spacer warm-edge seal. Our standard package.
U 0.27 · SHGC 0.28
Triple-pane · Ultra-S glassUpgrade for colder rooms and lower bills.
U 0.20 · SHGC 0.24
Triple-pane · Ultimate glassThe best thermal performance we offer.
U 0.17 · SHGC 0.24
Air infiltrationLower is tighter. Elements line.
as low as 0.01 cfm
ENERGY STAR 7.0Qualifying configurations, every U.S. climate zone.
Certified

Placeholder values from our published glass packages — your exact NFRC label (U-factor, SHGC, VT) is confirmed per configuration when we measure. The window carries our Limited Lifetime warranty; your installation carries ours.

Make It Yours

Colors, grids, and glass.

Custom-built means you choose. A sample of what we offer — full menu at your in-home visit.

Interior finishes
Soft-WhiteBeigeMedium OakLight OakBrazilian Cherry
Exterior colors
BlackBronzeForest GreenTerratoneSandstoneRoyal BrownGray+ custom match
Grids & glass
Colonial gridsPrairieFlat / contouredSimulated Divided LiteTriple-paneObscure / privacyTemperedLaminated (sound)
Take Your Time

Ready when you are.

Casement might be the right fit. It might not. Either way, we’d rather have that conversation in person than push you toward a decision on a website.

Get Your Free Quote
Slider Windows

Wide openings. Clean lines. Modern homes.

Horizontal glide. Simple operation. Perfect for contemporary architecture and wider openings. A clean visual line for mid-century and modern homes.

What They Are

A slider window has one or more sashes that glide horizontally on a track. The design is common in mid-century ranch homes and contemporary architecture where the horizontal line matters more than the vertical.

Because sliders open horizontally, they fit well in wide openings that would be awkward for a double-hung or casement. And with fewer moving parts than either alternative, they tend to require less maintenance over time.

Why Homeowners Choose Them

Slider windows are the right pick when you want a horizontal design language, wide openings without a center mullion, or minimal hardware maintenance. They’re a natural fit for ranches, contemporary homes, and rooms where a low horizontal line matters.

One thing to know: sliders open only half the width at a time. For maximum ventilation across a wide opening, casement or awning windows deliver more airflow per square foot.

Simple operation. Wide views. Clean sightlines.
— On Sliders
What We Install

The specifics.

Every unit is built to your exact opening dimensions . Here’s what’s inside.

01

Frame & Build

Fusion-welded, K-Beam-reinforced uPVC on a low-profile sill built for wide, short openings.

02

The Glide

DuraRoller stainless ball-bearing rollers carry the sash for smooth one-finger operation that keeps working for decades — no springs, no cranks.

03

Cleaning & Config

Swing & Clean sashes tilt in for easy cleaning. Available as a 2-lite glider or a 3-lite end-vent for very wide openings.

Built

Three ways to spec it.

Every window is custom-built to your exact opening — premium American-made vinyl sold only through installers, never big-box. Good, better, best:

Good

Pro

High-performance value with “practically limitless” customization. A strong, efficient everyday window that still outperforms most of what’s on the market.

Better

Imperial Elite

The premium line — named ENERGY STAR Most Efficient 2025. K-Beam reinforcement with Kevlar and the UltraSmart triple-fin antimicrobial weatherseal.

Best

Elements

The flagship. Industry-best 0.01 cfm air infiltration, ComfortFoam-insulated frame, Super Spacer, and the Dual-Action Invisible Tilt hardware.

Placeholder: which series we lead with as our standard offer is still being finalized — we’ll set that before launch.

Energy & Performance

The numbers.

Sliders suit contemporary elevations and openings that are wider than they are tall. Nothing to crank or lift — just a clean horizontal glide.

Double-pane · Low-E · argonSuper Spacer warm-edge seal. Our standard package.
U 0.27 · SHGC 0.28
Triple-pane · Ultra-S glassUpgrade for colder rooms and lower bills.
U 0.20 · SHGC 0.24
Triple-pane · Ultimate glassThe best thermal performance we offer.
U 0.17 · SHGC 0.24
Air infiltrationLower is tighter. Elements line.
as low as 0.01 cfm
ENERGY STAR 7.0Qualifying configurations, every U.S. climate zone.
Certified

Placeholder values from our published glass packages — your exact NFRC label (U-factor, SHGC, VT) is confirmed per configuration when we measure. The window carries our Limited Lifetime warranty; your installation carries ours.

Make It Yours

Colors, grids, and glass.

Custom-built means you choose. A sample of what we offer — full menu at your in-home visit.

Interior finishes
Soft-WhiteBeigeMedium OakLight OakBrazilian Cherry
Exterior colors
BlackBronzeForest GreenTerratoneSandstoneRoyal BrownGray+ custom match
Grids & glass
Colonial gridsPrairieFlat / contouredSimulated Divided LiteTriple-paneObscure / privacyTemperedLaminated (sound)
Take Your Time

Ready when you are.

Slider might be the right fit. It might not. Either way, we’d rather have that conversation in person than push you toward a decision on a website.

Get Your Free Quote
Bay & Bow Windows

More light. More space. More character.

A room-changing architectural feature. Adds interior space, catches light from three angles, and delivers instant curb appeal. The choice when you want a room to feel different.

What They Are

A bay window projects outward from the house in three sections — typically a large picture window in the center with operable double-hungs or casements on either side. A bow window uses four or more equal-sized sections curved gently outward.

Both add interior space (usable for seating or storage), pull light from three different angles, and dramatically change how a room feels. They’re also the strongest curb-appeal upgrade in the window category.

Why Homeowners Choose Them

Bay and bow windows are the right pick when you want to transform a specific room, add architectural character, or create a natural reading nook. Common in living rooms, breakfast nooks, and master bedrooms.

One thing to know: because they project out from the wall, installation is more complex than a flat replacement. Structural support, roof cap detail, and interior finish all matter. Not every opening is a candidate — we’ll tell you honestly when we measure.

Adds architectural character. Adds interior space.
— The Room-Changer
What We Install

The specifics.

Every unit is built to your exact opening dimensions . Here’s what’s inside.

01

The Assembly

A factory-assembled projection unit with insulated head and seat boards (birch veneer or laminate) and a concealed cable and knee-brace support system rated for the load.

02

Configuration

Bay: three units at a 30° or 45° angle. Bow: four or more in a gentle curve. Operating end units (double-hung or casement) for airflow, a big fixed unit in the center for the view.

03

Glass & Build

Same Low-E and triple-pane glass packages as the rest of the line, so the whole assembly performs as one.

Built

Three ways to spec it.

Every window is custom-built to your exact opening — premium American-made vinyl sold only through installers, never big-box. Good, better, best:

Good

Pro

High-performance value with “practically limitless” customization. A strong, efficient everyday window that still outperforms most of what’s on the market.

Better

Imperial Elite

The premium line — named ENERGY STAR Most Efficient 2025. K-Beam reinforcement with Kevlar and the UltraSmart triple-fin antimicrobial weatherseal.

Best

Elements

The flagship. Industry-best 0.01 cfm air infiltration, ComfortFoam-insulated frame, Super Spacer, and the Dual-Action Invisible Tilt hardware.

Placeholder: which series we lead with as our standard offer is still being finalized — we’ll set that before launch.

Energy & Performance

The numbers.

A bay or bow pushes the wall outward — adding a light-filled interior sill, capturing views from three angles, and genuinely changing how a room feels. It’s the one window that’s also a small remodel.

Double-pane · Low-E · argonSuper Spacer warm-edge seal. Our standard package.
U 0.27 · SHGC 0.28
Triple-pane · Ultra-S glassUpgrade for colder rooms and lower bills.
U 0.20 · SHGC 0.24
Triple-pane · Ultimate glassThe best thermal performance we offer.
U 0.17 · SHGC 0.24
Air infiltrationLower is tighter. Elements line.
as low as 0.01 cfm
ENERGY STAR 7.0Qualifying configurations, every U.S. climate zone.
Certified

Placeholder values from our published glass packages — your exact NFRC label (U-factor, SHGC, VT) is confirmed per configuration when we measure. The window carries our Limited Lifetime warranty; your installation carries ours.

Make It Yours

Colors, grids, and glass.

Custom-built means you choose. A sample of what we offer — full menu at your in-home visit.

Interior finishes
Soft-WhiteBeigeMedium OakLight OakBrazilian Cherry
Exterior colors
BlackBronzeForest GreenTerratoneSandstoneRoyal BrownGray+ custom match
Grids & glass
Colonial gridsPrairieFlat / contouredSimulated Divided LiteTriple-paneObscure / privacyTemperedLaminated (sound)
Take Your Time

Ready when you are.

Bay & Bow might be the right fit. It might not. Either way, we’d rather have that conversation in person than push you toward a decision on a website.

Get Your Free Quote
Picture Windows

Maximum light. Zero interruption.

Fixed glass. No moving parts. The strongest energy performance in the vinyl category and an uninterrupted view of whatever’s outside your home.

What They Are

A picture window is a fixed pane of glass — it doesn’t open. Because there are no moving parts, no operable sash, and no hardware, picture windows deliver the tightest possible seal in the vinyl category.

They’re also cheaper per square foot than operable windows, and they let you frame views without any visual interruption. Common uses: capturing a mountain view, a backyard oasis, or a large architectural focal point.

Why Homeowners Choose Them

Picture windows are the right pick when you want to frame a specific view, maximize daylight, or pair with operable windows to create a larger visual expanse. Often used as the centerpiece with casements or awnings flanking for ventilation.

One thing to know: because they don’t open, picture windows offer zero ventilation. In any room that needs airflow, you’ll want at least one operable window paired alongside.

Maximum light. Zero interruption.
— On Picture Windows
What We Install

The specifics.

Every unit is built to your exact opening dimensions . Here’s what’s inside.

01

Best-in-Line Performance

No moving parts means the tightest seal and the best thermal numbers we offer — let the picture window carry the view and let the units beside it do the venting.

02

Slim Sightlines

Bainbridge LE slimline frames maximize glass and viewing area, so you see more window and less vinyl across a big opening.

03

Glass & Build

Fusion-welded, K-Beam-reinforced uPVC with the full Low-E / triple-pane menu. Tempered safety glass where code requires it.

Built

Three ways to spec it.

Every window is custom-built to your exact opening — premium American-made vinyl sold only through installers, never big-box. Good, better, best:

Good

Pro

High-performance value with “practically limitless” customization. A strong, efficient everyday window that still outperforms most of what’s on the market.

Better

Imperial Elite

The premium line — named ENERGY STAR Most Efficient 2025. K-Beam reinforcement with Kevlar and the UltraSmart triple-fin antimicrobial weatherseal.

Best

Elements

The flagship. Industry-best 0.01 cfm air infiltration, ComfortFoam-insulated frame, Super Spacer, and the Dual-Action Invisible Tilt hardware.

Placeholder: which series we lead with as our standard offer is still being finalized — we’ll set that before launch.

Energy & Performance

The numbers.

A fixed picture window doesn’t open — which is exactly why it seals tighter and insulates better than anything that does. Flank it with double-hungs or casements for airflow.

Double-pane · Low-E · argonSuper Spacer warm-edge seal. Our standard package.
U 0.27 · SHGC 0.28
Triple-pane · Ultra-S glassUpgrade for colder rooms and lower bills.
U 0.20 · SHGC 0.24
Triple-pane · Ultimate glassThe best thermal performance we offer.
U 0.17 · SHGC 0.24
Air infiltrationLower is tighter. Elements line.
as low as 0.01 cfm
ENERGY STAR 7.0Qualifying configurations, every U.S. climate zone.
Certified

Placeholder values from our published glass packages — your exact NFRC label (U-factor, SHGC, VT) is confirmed per configuration when we measure. The window carries our Limited Lifetime warranty; your installation carries ours.

Make It Yours

Colors, grids, and glass.

Custom-built means you choose. A sample of what we offer — full menu at your in-home visit.

Interior finishes
Soft-WhiteBeigeMedium OakLight OakBrazilian Cherry
Exterior colors
BlackBronzeForest GreenTerratoneSandstoneRoyal BrownGray+ custom match
Grids & glass
Colonial gridsPrairieFlat / contouredSimulated Divided LiteTriple-paneObscure / privacyTemperedLaminated (sound)
Take Your Time

Ready when you are.

Picture might be the right fit. It might not. Either way, we’d rather have that conversation in person than push you toward a decision on a website.

Get Your Free Quote
Sliding Patio Doors

Bring the outside in.

Smooth operation. Energy-efficient glass. Built for Tennessee weather — from Knoxville summers to lake-effect winters.

What They Are

A sliding patio door is a large glass opening that connects an interior room to an outdoor space — patio, deck, or backyard. One or both panels slide horizontally on a track.

Modern vinyl patio doors are dramatically more efficient than the aluminum doors they typically replace. Multi-point locks, dual-pane insulating glass, and modern weatherstripping deliver energy performance closer to a wall than to an old door.

Why Homeowners Choose Them

Sliding patio doors are the right pick when you want to open up a room to outdoor living, maximize the visual connection to your yard, or replace a failing older door. Most common on the back of the home connecting to a deck or patio.

One thing to know: patio door installation typically involves more framing work than a standard window because you’re working with a larger opening. We’ll assess the framing when we measure and tell you honestly what the install involves.

Smooth. Sealed. Built for Tennessee weather.
— On Patio Doors
What We Install

The specifics.

Every unit is built to your exact opening dimensions . Here’s what’s inside.

01

The Door

Kingsroyal Glide sliding patio door in fusion-welded, foam-filled vinyl. Tandem stainless rollers carry the panel on a reinforced sill; available up to 8-ft heights.

02

Security & Seal

A 2-point mortise lock, interlocking meeting rails, and multi-fin weatherstripping. A BetterVue high-definition fiberglass screen is included.

03

Glass & Build

The same Low-E / argon (and triple-pane) glass packages as the windows, so the whole opening performs as one system. Tempered safety glass standard.

Built

Three ways to spec it.

Every window is custom-built to your exact opening — premium American-made vinyl sold only through installers, never big-box. Good, better, best:

Good

Pro

High-performance value with “practically limitless” customization. A strong, efficient everyday window that still outperforms most of what’s on the market.

Better

Imperial Elite

The premium line — named ENERGY STAR Most Efficient 2025. K-Beam reinforcement with Kevlar and the UltraSmart triple-fin antimicrobial weatherseal.

Best

Elements

The flagship. Industry-best 0.01 cfm air infiltration, ComfortFoam-insulated frame, Super Spacer, and the Dual-Action Invisible Tilt hardware.

Placeholder: which series we lead with as our standard offer is still being finalized — we’ll set that before launch.

Energy & Performance

The numbers.

A slider brings the outside in without swinging into the room, and it matches the windows in color, grid, and glass so the elevation reads as one system.

Double-pane · Low-E · argonSuper Spacer warm-edge seal. Our standard package.
U 0.27 · SHGC 0.28
Triple-pane · Ultra-S glassUpgrade for colder rooms and lower bills.
U 0.20 · SHGC 0.24
Triple-pane · Ultimate glassThe best thermal performance we offer.
U 0.17 · SHGC 0.24
Air infiltrationLower is tighter. Elements line.
as low as 0.01 cfm
ENERGY STAR 7.0Qualifying configurations, every U.S. climate zone.
Certified

Placeholder values from our published glass packages — your exact NFRC label (U-factor, SHGC, VT) is confirmed per configuration when we measure. The window carries our Limited Lifetime warranty; your installation carries ours.

Make It Yours

Colors, grids, and glass.

Custom-built means you choose. A sample of what we offer — full menu at your in-home visit.

Interior finishes
Soft-WhiteBeigeMedium OakLight OakBrazilian Cherry
Exterior colors
BlackBronzeForest GreenTerratoneSandstoneRoyal BrownGray+ custom match
Grids & glass
Colonial gridsPrairieFlat / contouredSimulated Divided LiteTriple-paneObscure / privacyTemperedLaminated (sound)
Take Your Time

Ready when you are.

Patio Doors might be the right fit. It might not. Either way, we’d rather have that conversation in person than push you toward a decision on a website.

Get Your Free Quote
Where We Work

Serving Knoxville and East Tennessee.

Six cities. Same standard. Local company. Local crews. Same phone number.

K

Knoxville

From Sequoyah Hills to Fountain City, Bearden to West Hills — premium vinyl windows for the neighborhoods we know.Learn More

F

Farragut

For the West Knoxville homes built to last — windows that match the standard....

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M

Maryville

For Blount County homes — historic and new — installed by neighbors, not a call center....

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O

Oak Ridge

For the Secret City’s homes — from the original Cemestos to modern builds....

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L

Lenoir City

For Fort Loudon Lake homes and Loudon County residents — waterfront quality installations....

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J

Jefferson City

For Jefferson County homes — installed by a company that actually shows up....

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Take Your Time

Serving your area?

If you’re anywhere within about a 45-minute drive of Knoxville, we probably serve you. Give us a call and we’ll tell you honestly.

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Serving Knoxville

Window Replacement in Knoxville, TN.

From Sequoyah Hills to Fountain City, Bearden to West Hills — premium vinyl windows for the neighborhoods we know.

Get Your Knoxville Quote
Why Knoxville Homeowners Choose Us

Knoxville is a city of neighborhoods with real character. From 1920s bungalows in Old North Knoxville to mid-century ranches in West Hills, from sprawling colonials in Sequoyah Hills to newer builds in Farragut — most Knoxville homes are past the useful life of their original windows.

Our crews live here. This isn’t a franchise or a corporate branch office — this is a Knoxville company serving Knoxville homeowners.

Knoxville neighborhoods we serve

Sequoyah HillsBeardenCedar BluffWest HillsFountain CityOld North KnoxvillePowellHallsKarns
We’re a Knoxville company serving Knoxville homeowners. Not a corporate branch office.
— Stubborn Mule Window Co.
Common Knoxville Projects

Most Knoxville homes we work on are 20-40+ years old. The original single-pane or early double-pane windows have failed seals, drafty frames, and rising energy bills to show for it. Our typical Knoxville project is a whole-house install of 10-15 double-hung vinyl windows.

Take Your Time

Ready when you are, Knoxville.

Get a straight quote from a company that lives about thirty minutes from your front door. Written estimate good for 90 days. No pressure. No games.

Get Your Free Quote
Serving Farragut

Window Replacement in Farragut, TN.

For the West Knoxville homes built to last — windows that match the standard.

Get Your Farragut Quote
Why Farragut Homeowners Choose Us

Farragut’s a town of newer builds, quality schools, and homeowners who care about their properties. Most Farragut homes were built in the 1980s and 1990s — which means the original windows are 30-40 years old and ready for their first replacement.

We work through Farragut neighborhoods every week. Village Green, Concord, Fox Den — we know the housing stock, the HOA nuances, and what looks right on West Knoxville homes.

Farragut neighborhoods we serve

Village GreenConcordFox DenTurkey CreekFarragut EstatesKingsgateBelleaire
We know what looks right on West Knoxville homes. Because we’re in them every week.
— Stubborn Mule Window Co.
Common Farragut Projects

Whole-house replacements are typical here — homeowners investing in the long-term value of larger properties. Double-hung and casement combinations are common on Farragut colonials and transitional-style homes.

Take Your Time

Ready when you are, Farragut.

Get a straight quote from a company that lives about thirty minutes from your front door. Written estimate good for 90 days. No pressure. No games.

Get Your Free Quote
Serving Maryville

Window Replacement in Maryville, TN.

For Blount County homes — historic and new — installed by neighbors, not a call center.

Get Your Maryville Quote
Why Maryville Homeowners Choose Us

Maryville’s a mix. Historic downtown craftsman homes with original wood windows past their useful life. Newer developments along Alcoa Highway with builder-grade windows that never performed well. Both need real replacement — not cheap upgrades.

We know the difference between preserving character on a historic home and modernizing efficiency on a 90s ranch. Different jobs. Same standard.

Maryville neighborhoods we serve

Downtown Historic DistrictSpringbrookFoothills Mall areaAlcoa Highway corridorMaryville College areaLouisville
Different jobs. Same standard.
— Stubborn Mule Window Co.
Common Maryville Projects

Historic homes need windows that respect the architecture — often double-hung with grille patterns matching the original. Newer homes typically want efficiency upgrades. We do both without compromising either.

Take Your Time

Ready when you are, Maryville.

Get a straight quote from a company that lives about thirty minutes from your front door. Written estimate good for 90 days. No pressure. No games.

Get Your Free Quote
Serving Oak Ridge

Window Replacement in Oak Ridge, TN.

For the Secret City’s homes — from the original Cemestos to modern builds.

Get Your Oak Ridge Quote
Why Oak Ridge Homeowners Choose Us

Oak Ridge is a unique housing market. The original alphabet houses (A, B, C, D, E, F, K) from the Manhattan Project era have distinctive window configurations that need careful matching. Newer developments in West Hills and beyond need modern efficiency.

We understand both. Oak Ridge homeowners often care about historical character and energy bills. We can deliver both without compromise.

Oak Ridge neighborhoods we serve

East VillageWoodlandEmory ValleyWest HillsHighland ViewEast ForkRobertsville
Historical character. Modern efficiency.
— Stubborn Mule Window Co.
Common Oak Ridge Projects

Historic alphabet houses often need custom-sized replacements to match original openings — we can source these. Modern homes typically benefit from full-house double-hung or casement replacements for immediate energy savings.

Take Your Time

Ready when you are, Oak Ridge.

Get a straight quote from a company that lives about thirty minutes from your front door. Written estimate good for 90 days. No pressure. No games.

Get Your Free Quote
Serving Lenoir City

Window Replacement in Lenoir City, TN.

For Fort Loudon Lake homes and Loudon County residents — waterfront quality installations.

Get Your Lenoir City Quote
Why Lenoir City Homeowners Choose Us

Lenoir City’s growing fast. New developments along Fort Loudon Lake, waterfront properties needing serious weather protection, older homes in the historic downtown. All benefit from the same standard: premium vinyl, done right, warrantied for life.

Lakefront homes see brutal weather cycles. Sun, humidity, wind off the water. The windows have to hold up. We install for the environment they’ll live in.

Lenoir City neighborhoods we serve

Downtown Lenoir CityRarity BayTellico Village adjacentFort Loudon waterfrontHighway 321 corridorLoudon
We install for the environment they’ll actually live in.
— Stubborn Mule Window Co.
Common Lenoir City Projects

Waterfront installations get our attention on hardware — stainless steel across the board. Newer developments often benefit from casement upgrades for tighter seals against lake weather.

Take Your Time

Ready when you are, Lenoir City.

Get a straight quote from a company that lives about thirty minutes from your front door. Written estimate good for 90 days. No pressure. No games.

Get Your Free Quote
Serving Jefferson City

Window Replacement in Jefferson City, TN.

For Jefferson County homes — installed by a company that actually shows up.

Get Your Jefferson City Quote
Why Jefferson City Homeowners Choose Us

Jefferson City’s a smaller market with older housing stock and strong community. The homes here have been maintained for generations — often waiting for the right time for a full window replacement.

We’re not a Knoxville company that says they serve Jefferson City. We’re a Knoxville company that actually shows up. Same crews, same standards, same phone number.

Jefferson City neighborhoods we serve

Downtown HistoricCarson-Newman University areaRoute 92 corridorDandridge HighwayHwy 11E area
A Knoxville company that actually shows up.
— Stubborn Mule Window Co.
Common Jefferson City Projects

Older brick homes typically need traditional double-hung replacements with authentic grille patterns. Newer builds often benefit from efficiency upgrades to reduce heating costs.

Take Your Time

Ready when you are, Jefferson City.

Get a straight quote from a company that lives about thirty minutes from your front door. Written estimate good for 90 days. No pressure. No games.

Get Your Free Quote
Payment Options

Payment plans for every budget.

Same-as-cash promotional plans. Reduced-rate long-term financing. Or just pay cash. We don’t push financing.

Our Approach

Every window company has a financing pitch. Ours is short: use it if it helps you, skip it if it doesn’t.

We don’t get paid more if you finance. We don’t get paid less if you pay cash. Our prices are the same either way.

Use financing if it helps. Skip it if it doesn’t. Either way, the price is the same.
— Our Financing Philosophy
Full Transparency

Something most companies won’t tell you: we pay a dealer fee to the finance company on every financed project. That fee is built into our prices already. Same price whether you finance or pay cash.

Common Questions

Does financing change my price?

No. Same price whether you finance or write us a check.

Is there a prepayment penalty?

Not with the plans we offer. Pay off any loan early without penalty.

What if I don’t qualify?

We’ll tell you honestly and move on. Nobody gets pressured, nobody gets ghosted.

Take Your Time

Numbers ready when you are.

We’ll give you an exact project quote — good for 90 days — and walk through the options. No pressure to finance. No pressure to sign.

Get Your Free Quote
The Warranty

Lifetime means lifetime.

Non-prorated. Transferable. Covers frame, glass, hardware, and our labor. Not just the good parts — the whole thing.

What "Lifetime" Actually Means

Most window companies use the word "lifetime" and hope you don’t ask what it means. Here’s what it means at Stubborn Mule:

For as long as you own the home, your windows are covered. If you sell, the warranty transfers to the next owner. No re-registration fee. No lapse.

Non-prorated means we don’t reduce coverage over time. A twenty-year-old failed seal gets the same treatment as a two-year-old failed seal.

A warranty is only as good as the company standing behind it.
— The Warranty Standard
Full Coverage Detail

We publish the exact coverage on this page — no fine print, no PDF download.

Vinyl frame & sashWarping, cracking, discoloration, corner failure.
Covered
Insulated glass unit (seal failure)Fog or condensation between panes.
Covered
Hardware (locks, hinges, cranks, balances)Everything moving. Normal use.
Covered
Weatherstripping & sealsRubber and foam that keeps weather out.
Covered
Our installation laborNo labor charge, ever.
Covered
Storm/impact damageTree branch, hail, baseball. File with homeowner’s insurance.
Not Covered
Home settling or foundation movementHome structure issue, not window failure.
Not Covered
Modifications by othersDrilled, cut, or altered by someone else.
Not Covered
How Claims Work

You call the number on the truck. Or the contract. Or this website. All go to the same place. We schedule a service visit within a week — usually within 48 hours in Knoxville. No claim forms. No proof-of-purchase to dig up.

Take Your Time

Read it. Compare it.

Take our warranty to any other window company and ask them to match it — in writing, non-prorated, transferable, covering labor. Most won’t.

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Our Process

Four steps. No games.

How a Stubborn Mule project actually goes. From first call to lifetime warranty.

The Full Path

Take your time at every step.

We’re not going anywhere.

Step 01 — The Visit

Free Consultation

One hour at your home — that’s our cap. We measure every opening and answer your questions, then we’re out. No sales pressure, no "manager approval" theater, no three-hour living-room presentation. We stay longer only if you want us to.

Step 02 — The Number

Written Quote

Itemized. Clear. Good for 90 days. Take your time. Get other quotes. We’ll still be here.

Step 03 — The Build

Custom Built

Every window manufactured to your exact opening dimensions. 4-6 weeks.

Step 04 — The Install

Pro Install

Full crew, typically 1-2 days for whole-house. Sealed. Trim finished. Warranty registered.

What Makes This Different

Most window companies use the visit as a sales presentation. Two to three hours in your living room, escalating discount tiers, "manager approval" theater, pressure to sign tonight.

We don’t do any of that. Our visit is a measurement and a conversation. We get you a written quote. We leave. If you want to hire us, you tell us — days or weeks or months later. The price on the quote is the price. It doesn’t move.

The price on the quote is the price. It doesn’t move.
— The Rule
Take Your Time

Ready when you are.

Get a straight quote from a company that shows up when they say they will, does the work right, and stands behind it for life. No pressure, no follow-up spam, no games.

Get Your Free Quote
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