WBI American-Made Radiant Panels, Tariff-Free Pricing, Stocked & Ready to Ship Learn More
Call Us
877-924-3899 8AM-5PM Central Time
  • Shopping Cart Shopping Cart
    0Shopping Cart
Contact Us
  • Our Brands
    • Ecowarm RadiantBoard
    • ThermalBoard
    • InsulHeat
  • Specification
  • Installation
    • Installation Manuals
    • Ecowarm RadiantBoard Installation Video
    • ThermalBoard Installation Video
    • Finished Flooring Goods
  • Applications
    • Installation Over Insulated Subfloor
    • Installation Over Concrete
    • Installation Over Under-Insulated Subfloor
    • Installation Over Walls & Ceilings
  • About
    • Our Team
    • Blog
  • Contact Us
  • Menu Menu

Radiant Floor Heating for Retrofit and Remodeling

Thermalboard Home Graphic

Thermalboard is the retrofit radiant floor heating solution

Thermalboard features a low profile, a high efficiency aluminum surface and sustainable substrate. The standard panel’s 5/8” low profile can be accommodated in most existing structures for retrofit and remodeling; it is lightweight and easy to cut and is effective for smaller jobs.

Thermalboard is easy to install by any general contractor following our panel layout and step by step installation manual. It also provides a very quick responding and efficient solution for comfort and lowers energy bills.

Get a Free Quote Factory Direct to Your Jobsite
  • Cost Effective
  • Low Profile (5/8″)
  • Easy Installation
  • Factory Direct
  • Retrofit & Remodel Friendly
  • Retrofit Under Floor Joists
  • High Performance
  • Layout Design
  • Sustainable
  • Light Weight

Cost Effective

Thermalboard delivers high performance at a competitive cost, especially when compared to gypsum cement or structural plywood radiant systems. The minimal labor and equipment required help reduce the total project budget while maintaining premium comfort levels.

Low Profile (5/8″)

Its slim 5/8″ thickness makes it an ideal solution for retrofit projects. This low-profile radiant heating panel integrates easily into existing floor assemblies without causing changes to thresholds or door swing issues.

Easy Installation

Designed for simplicity, Thermalboard panels come pre-engineered for quick layout and assembly. Standard tools are sufficient for cutting and fitting, making it DIY-friendly and saving professional installers valuable time on-site.

Factory Direct

By purchasing directly from the manufacturer, you reduce delays, avoid middlemen, and ensure product authenticity. Our factory-direct radiant heating panels come with full support, from CAD layouts to step-by-step manuals.

Retrofit & Remodel Friendly

Thermalboard is a top choice for remodelers. It integrates seamlessly with most existing structures, allowing radiant heat upgrades without major tear-outs or construction. Especially suited for remodel radiant heat flooring projects in kitchens, bathrooms, or full-home makeovers.

Retrofit Under Floor Joists

We offer solutions that can be configured under joists as well. When above-floor installation isn’t feasible, Thermalboard’s system allows efficient radiant heating to be applied from below, ideal for existing subfloors.

High Performance

With an aluminum surface that conducts heat far better than wood or gypsum, Thermalboard delivers superior heat transfer, energy savings, and a more comfortable living space. Fast response times ensure your space heats quickly and evenly.

Layout Design

We provide CAD-based layout designs tailored to your space and project goals. Each layout includes tubing paths, manifold locations, and panel arrangements, ensuring easy, foolproof installation.

Sustainable

Thermalboard is made using 92% pre-consumer recycled content, contains zero formaldehyde, and qualifies for LEED® v4 credits. A smart choice for environmentally responsible builders and homeowners looking to reduce carbon impact.

Light Weight

Its lightweight construction makes it easy to handle, transport, and install—even on upper floors. This cuts down labor, reduces strain, and makes it possible to do solo installations.

Thermalboard Layout Design Example

CAD Panel Layout Included

Save hours of labor with our free design & layout services

Our layout service includes the location of RadiantBoard panels, tubing and manifold locations. A CAD layout is highly recommended to ease installation and save hours of labor for inexperienced installers.

Design & Layout Services
Thermalboard Radiant Floor Heating Sample
Thermalboard EPS Radiant Floor Heating Sample
Application Manual

Common methods for retrofit radiant floor heating and remodeling

Radiant heat remodels can go into a new concrete floor addition, under an existing subfloor or in a thermal panel, like Thermalboard, on top of a subfloor or existing concrete slab.

While underfloor staple up radiant systems can resolve issues with existing flooring goods, underfloor systems are far less efficient, respond more slowly and are time consuming to install.

Radiant Heat Retrofit of Existing
Hydronic System

If you have an existing baseboard or other type of system, Thermalboard can be an excellent upgrade solution. Just keep in mind that if you have an existing high temperature radiator or baseboard system, a mixing valve must be installed to lower the temperature entering the Thermalboard radiant section of your system.

View Installation Manual

Ideal Retrofit Applications for Thermalboard

Thermalboard shines in a variety of retrofit situations, offering flexibility, performance, and ease of installation in spaces where traditional radiant systems may not be feasible.

 1. Older Homes with Limited Floor Height

Older homes often feature unique architectural elements and fixed floor levels, making major floor height changes difficult or undesirable. Thermalboard’s low 5/8” profile allows it to be installed without the need to cut down doors, adjust baseboards, or alter transitions to other rooms. This makes it ideal for preserving the historical integrity of older homes while upgrading them with modern comfort.

2. Basement Finishing Projects

Basements typically have concrete slabs that are cold and uncomfortable underfoot. Thermalboard installs directly over concrete without requiring thick mud beds or additional structural layers. It not only helps regulate floor temperature but also creates a warm, inviting environment that transforms basements into livable, cozy spaces, perfect for home offices, guest suites, or entertainment areas.

3. Kitchen and Bathroom Renovations

Kitchens and bathrooms are high-traffic areas where comfort and quick temperature response matter most. Thermalboard’s aluminum surface provides fast and even heat transfer, ensuring the space warms up quickly when needed. It integrates well beneath tile, vinyl, and engineered hardwood, making it an excellent choice for small-area renovations that demand high performance.

4. ADU or Garage Conversions

When converting garages or building Accessory Dwelling Units (ADUs), you often work with minimal structural depth and unconditioned concrete floors. Thermalboard offers a practical radiant solution that doesn’t require thick pours or additional subfloor systems. It installs easily over existing surfaces and helps regulate temperature in these repurposed areas year-round, improving comfort and energy efficiency.

Installation Videos

Follow the guide for a quick installation overview of Thermalboard. For more detailed instructions you can download our free Installation Manual here.

View Installation Guide

Installation Guide with Step by Step Instructions

Step by Step Installation Guide

Need more installation tips? Check out this step-by-step guide!

View Steps

Easy Installation with Thermalboard

See the installation of a Thermalboard licensed product in a major remodel.

Tubes placed under floor as part of retrofit radiant floor heating
retrofit radiant floor heating animation in house
Illustration of a house floor featuring radiant heat panels

Why Choose Thermalboard Over Traditional Systems?

Thermalboard stands out from traditional radiant systems like gypcrete and structural plywood panels by offering superior efficiency, convenience, and adaptability. Here’s a closer look at its advantages:

1. No Curing Time

Unlike gypcrete systems, which require several days of curing before floor coverings can be installed, Thermalboard is dry-installed and ready for immediate use. This allows faster project timelines and reduced labor costs, flooring can be placed the same day the radiant system is installed.

2. No Added Structural Load

Panels are lightweight, which means they won’t stress existing floor joists or require reinforcement like heavier concrete-based systems. This is especially beneficial for second-story installations or retrofitting older homes with limited load capacity.

3. Compatible with Multiple Floor Coverings

Whether you’re planning to install hardwood, tile, luxury vinyl tile (LVT), engineered wood, or even carpet, Thermalboard offers consistent performance. The even heat distribution provided by its aluminum top layer ensures compatibility and comfort regardless of the flooring material.

4. Precision Panel Layouts

Thermalboard includes custom CAD-based panel layouts, making installation easier and more efficient. These layouts include tubing paths, panel placements, and manifold locations, minimizing waste, preventing mistakes, and reducing time on-site.

Frequently Asked Questions (FAQ)

Q: Can Thermalboard be used in every room during a remodel?

Yes! Its low profile and lightweight design make it ideal for any room, basements, bathrooms, kitchens, attics, and even upper floors, without requiring structural changes. Perfect for whole-home remodels and focused upgrades alike.

Q: Is this system energy efficient enough for older homes?

Absolutely. The aluminum surface ensures faster, more even heating, helping offset energy inefficiencies common in older structures, reducing boiler load and energy bills even in draft-prone remodels.

Q: How soon after installing Thermalboard during a renovation can I place flooring?

Immediately. Unlike wet systems, Thermalboard needs no curing or drying, helping you stay on schedule and get to flooring installation the same day.

Q: Does Thermalboard need special tools or advanced skills for retrofit installation?

No special tools are required. Standard construction tools are all you need. Our CAD panel layouts and step-by-step manuals make the process simple for general contractors, remodelers, and even handy homeowners.

Q: Can Thermalboard be installed over old subfloors or concrete?

Yes, Thermalboard installs easily over existing plywood subfloors, concrete slabs, or even finished floors, making it ideal for retrofits where demolition is minimized.

Q: Is Thermalboard light enough for second stories or retrofits?

Yes. It’s significantly lighter than gypcrete or poured systems, so it’s safe for second floors and older framing without added structural concerns.

Q: Is Thermalboard a good fit for remodels using heat pumps?

Definitely. Its high-conductivity aluminum surface makes it ideal for low-temperature heat sources like air-to-water or geothermal heat pumps, common in sustainable retrofits and energy-efficient home upgrades.

Q: Will it interfere with door thresholds or ceiling heights in a retrofit?

Not at all. At only 5/8″ thick, Thermalboard preserves floor-to-ceiling height and won’t affect door swing or transitions, ideal for seamless retrofitting.

Fast & Efficient Response Times

Thermalboard offers far higher efficiency and response time for radiant heat remodels than underfloor radiant heat and is easier to install.

Compare Radiant Systems

John Mann

Get Your Free Project Estimate

Delivered Factory Direct to your Jobsite

Call John at (866) 414–7244  for more information

Get a Quote
WBI Logo
  • About WBI
  • Our Team
  • Our Products
  • Installation
  • Hydronic Heat
  • Remodeling
  • Resources
  • Flooring Goods
  • Blog
  • Guides
facebooklinkedinInstagramYoutube
PO BOX 4680 Rollingbay, WA 98061
© 2025 The Radiant Panel Company® is a registered trademark of Warm Brothers Inc. All rights reserved.
  • Privacy Policy
  • Terms & Conditions
Scroll to top