Thermo-Rite

What Thermo-Rite does

TK Fireside (formerly Thermo-Rite Manufacturing) is a family-owned custom manufacturer of tempered glass fireplace enclosures, headquartered in Akron, Ohio, with operations continuing at the original manufacturing facility. The company originated the tempered glass fireplace enclosure category in 1942, when founder John E. Lydle secured the first U.S. patent for the product, held until 1968. In 2025, Brett Lyren, grandson of the founder, relaunched the business as TK Fireside to modernize operations while preserving handcrafted American manufacturing. The company is led by Brett Lyren, with Kim Schedlbauer (formerly of the David Kimberly Door Company) serving as partner for the Luxury Line.

The product portfolio spans three lines: masonry fireplace doors (seven models including Heritage, Normandy, Thin-Line, Celebrity, Cameo, Laser, and Reserve) for traditional brick, stone, and tile fireplaces; zero clearance doors (five models including Z Heritage, Z Door, Special Z, Z Laser, and Thin-Line Z) for pre-manufactured metal fireboxes; and the 2025 Luxury Line Collection, a high-end built-to-order line offering multiple opening shapes (Rectangular Square, Rectangular Flat Arch, Flat Arch, Full Arch, L-Shaped Corner, U Door) and configurable series (Reflection and Standard). Proprietary features include Air Studs and Air Draft Bar intake-preservation technologies for zero clearance applications and a hidden door-return track for clean one-piece aesthetics. All units are custom-built to the exact specifications of the fireplace opening, with nine powder-coat finishes available.

The business model is exclusively channel-based: products are sold through an authorized dealer network across the United States, with dealers handling on-site measurement, installation, pricing, and warranty registration. The company does not sell directly to consumers. Pricing is gated behind a dealer portal for the standard line, while the Luxury Line operates on a call-for-pricing, mult-year contract model for custom orders. Customer segments are concentrated in two primary homeowner groups: those with masonry fireplaces and those with zero clearance fireplaces, plus a secondary luxury residential segment. Marketing relies on the company website, including a dealer locator, browser-based Fireplace Visualizer tool, educational content, and dealer inquiry forms. Revenues are not publicly disclosed, and the company is privately held with 11-50 employees.

Name

Thermo-Rite

Legal name

TK Fireside

Website

https://thermo-rite.com

Company type

Private

Founded year

1942

Operating status

Operating

Headcount range

11–50 employees

Short description

TK Fireside (formerly Thermo-Rite) is a family-owned Akron, Ohio manufacturer of custom-crafted tempered glass fireplace enclosures (masonry, zero clearance, and luxury), founded in 1942 and relaunched in 2025, selling exclusively through authorized dealers to U.S. homeowners.

Ownership category

akta.pro rank

Product category

Fireplace Enclosures

NAICS

Heating Equipment (except Warm Air Furnaces) Manufacturing (333414), Metal Window and Door Manufacturing (332321)

SIC

Heating Equip, Except Elec & Warm Air; & Plumbing Fixtures (3430), Metal Doors, Sash, Frames, Moldings & Trim (3442)

akta.pro primary industry

Fire Pits & Outdoor Fireplaces (HSAIACAG)

Keywords

• Glass fireplace enclosures
• Custom fireplace doors
• Masonry fireplace doors
• Zero clearance doors
• Tempered safety glass

Headquarters

HQ city

Akron

HQ country

United States

HQ region

North America

Offices2 records

Markets served

GTM type

B2C

Offering type

Hardware or Manufacturing

Cost components

Supply Chain, Personnel, Operations, Marketing or Sales, Technology or R&D, Infrastructure

Revenue model

1. Glass Fireplace Enclosure Sales: Custom-crafted masonry, zero-clearance, and luxury glass fireplace enclosures sold through authorized dealers. Products are built to exact specifications of the fireplace opening.

Pricing tiers

Go-to-market motion1 record

Distribution channels1 record

Marketing channels5 records

Core offering

TK Fireside (formerly Thermo-Rite) manufactures custom-crafted tempered glass fireplace enclosures for masonry and zero clearance fireplaces, offered across 12 standard models plus a built-to-order Luxury Line collection. All products are handcrafted in Akron, Ohio and sold exclusively through an authorized dealer network that handles measurement, installation, pricing, and warranty registration.

Product overview

TK Fireside (formerly Thermo-Rite) is a manufacturer of custom glass fireplace enclosures founded in 1942, now operated by the founding family. The product portfolio consists of three main lines: (1) Masonry Doors — seven models (Heritage, Normandy, Thin-Line, Celebrity, Cameo, Laser, Reserve) for brick, stone, and tile fireplaces; (2) Zero Clearance Doors — five models (Z Heritage, Z Door, Special Z, Z Laser, Thin-Line Z) for pre-manufactured metal fireboxes; and (3) Luxury Line — a high-end built-to-order collection with multiple series (Reflection and Standard) offering customization across opening shapes (Rectangular Square, Rectangular Flat Arch, Flat Arch, Full Arch, L-Shaped Corner, U Door). All products are handcrafted in Akron, Ohio, and sold exclusively through authorized dealers. The company also offers a Fireplace Visualizer tool for in-browser door preview.

Differentiator

Problem solved

Functional benefit

Brands

• Luxury Line: A high-end, built-to-order collection developed with Kim Schedlbauer (formerly of David Kimberly Door Company), featuring new engineering, materials, and finishes unavailable on the standard TK Fireside line. Includes multiple series: Reflection Series 3 Bifold, Reflection Series 2 Bifold, Reflection Series Twin, and Standard Series Twin.

Products and services

• Masonry Fireplace Doors Custom-crafted glass fireplace enclosures designed for brick, stone, and tile masonry fireplaces, available in seven models including Heritage, Normandy, Thin-Line, Celebrity, Cameo, Laser, and Reserve, with inside or overlap fit options and multiple frame materials and finishes.
• Zero Clearance Fireplace Doors Glass fireplace enclosures designed for pre-manufactured metal fireboxes common in homes built or renovated since the 1960s, available in five models (Z Heritage, Z Door, Special Z, Z Laser, Thin-Line Z) that preserve the required air intakes of metal fireboxes using proprietary air-intake venting or Air Studs and Air Draft Bar systems.
• Luxury Line Collection High-end, built-to-order fireplace door collection developed with Kim Schedlbauer (formerly of David Kimberly Door Company), offering new engineering, materials, and finishes unavailable on the standard TK Fireside line, with opening shapes including Rectangular Square, Rectangular Flat Arch, Flat Arch, Full Arch, L-Shaped Corner, and U Door configurations.
• Reflection Series Luxury line product series available in 2-bifold, 3-bifold, and twin configurations, with design styles including Classic, Architect B-2, Architect B-2 Curved Bars, Architect B-2 Straight Bars, Architect B-3, Aztec, Architect A-3, Top Lite, and Narrow Window Pane.
• Standard Series (Luxury Line) Luxury line product series available in twin configurations (including an L-Shaped Corner twin variant), with design styles including Classic, Architect B-2 Curved Bars, Architect B-2 Straight Bars, Top Lite, New England 8 Pane, Diamond, and Narrow Window Pane.
• U Door (Luxury Line) Fully custom three-sided luxury fireplace door for U-shaped three-sided fireplace openings, requiring direct project contact for pricing discussion.

Quantifiable outcome

• Heat loss reduction through tempered glass enclosure vs open fireplace
• +1 more outcomes

Segments4 records

Ideal customer profiles4 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

One partnership is on record.

• Kim Schedlbauer (formerly David Kimberly Door Company)coreStrategic or Co-development Partner · 1 January 2025Kim Schedlbauer, formerly of David Kimberly Door Company, has partnered with TK Fireside to develop the Luxury Line collection. This partnership brings new engineering, materials, and finishes unavailable on the standard TK Fireside line. The Luxury Collection represents a high-end, built-to-order line launched in 2025.

Scale indicators4 records

Recent moves4 records

Expansion highlights4 records

Broad incumbents

• Travis Industries: Family-owned U.S. manufacturer of fireplaces, inserts, and stoves (Lopi, Fireplace Xtrordinair, DaVinci). A direct comparable in scale and family-ownership ethos, with a much broader product portfolio than TK Fireside's specialty enclosures.
• Hearth & Home Technologies: Largest U.S. manufacturer of hearth products, owning Heatilator, Heat & Glo, Quadra-Fire, and Majestic. While TK Fireside focuses narrowly on glass enclosures, HHT overlaps as a broad incumbent in the fireplace ecosystem and competes for dealer shelf space.
• Lennox Hearth Products: Hearth division of Lennox International, offering fireplaces, inserts, and stoves under the Lennox and Superior brands. A broad incumbent with national dealer reach that competes for the same end-customer renovation dollars.
• Napoleon (Wolf Steel): Canadian-based broad-line hearth manufacturer offering fireplaces, inserts, and stoves across gas, wood, and electric categories. Comparable as a multi-product fireplace OEM with national dealer distribution.
• Majestic Products (HHT brand): Mass-market hearth brand within the HHT portfolio offering fireplaces and accessories through big-box and independent dealer channels. Competes for the entry-level enclosure and surround purchase.

Others

• Woodland Direct: Online retailer of fireplaces, fireplace doors, inserts, and accessories from multiple manufacturers. Adjacent to TK Fireside as a distribution channel that sells competing enclosures alongside other hearth brands.

Direct peers

• Stoll Industries: Manufacturer of fireplace doors, surrounds, mantels, and accessories — the closest direct competitor to TK Fireside in custom glass fireplace enclosures for masonry and zero-clearance applications.
• Design Specialties: Specialty manufacturer of premium custom fireplace doors and enclosures serving both masonry and zero-clearance fireplaces, with similar fit-to-opening customization and dealer-channel distribution.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks7 records

Key highlights7 records

Customer concentration

• Xx.com/ThermoRite

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Thermo-Rite