What is Warmboard?
8035 Soquel Dr.
Aptos CA 95003
 PORTFOLIO (Click to enlarge)

What is Warmboard?

Warmboard combines a structural subfloor and a thermodynamically sophisticated radiant panel into one simple component of your radiant heating system. Warmboard begins with a stiff, strong, 1-1/8″ thick, 4′ X 8′ sheet of tongue and groove, weather-resistant plywood. A modular pattern of channels is cut into the top surface. A thick sheet of aluminum is stamped to match the channel pattern and is permanently bonded to each panel.

As a structural subfloor, Warmboard is stiff, strong and especially tough. It can be sawn with a Skilsaw and nailed or screwed directly to your floor joists just like any conventional subfloor. The same labor that would ordinarily install just a subfloor, installs a high performance radiant panel system, saving you time and labor from the very beginning. Other radiant heat systems are more labor intensive because they’re added either above or below the subfloor. Warmboard is the subfloor.

As Warmboard is installed, the four modular panel types create an infinite variety of radiant tubing layouts to suit the needs of any home. A roll of half-inch PEX tubing (the radiant industry standard for toughness, reliability, and performance) is then easily installed into the channel to complete the hydronic circuit.

Warmboard Overview

Why Warmboard provides better radiant heat

Warmboard has the two most important properties for excellent thermodynamic performance and radiant heat output:

  • High conductivity
  • Low thermal mass.

The importance of conductivity

The primary purpose of any radiant heat panel is to conduct heat to the living spaces of your home. Warmboard has been optimized for maximum conductivity, which means maximum radiant heat delivered from each drop of heated water.

The history section of our website, explains why many systems in the past have used concrete in one form or another to conduct heat. But concrete does not make sense in modern wood framed homes - consider this: Aluminum is hundreds of times more conductive than concrete!

There is a reason that frying pans are made out of aluminum and not concrete!

Warmboard was not the first radiant heat system to use aluminum, we just try to be a little smarter about how we use it. We begin with an especially high grade of aluminum. The conductive surface of Warmboard is essentially pure aluminum, which is 30% more conductive than the more common alloys other radiant panels use. Further still, some radiant panels use little more than aluminum foil to “conduct” radiant heat. Warmboard’s 24-gauge aluminum top surface is eight times as thick as the aluminum foil used in these systems. All things being equal, an eight fold increase in thickness means eight times as much radiant heat delivered by the aluminum plate on top of Warmboard. Furthermore, because your finished floor goods are in direct contact with Warmboard’s thick aluminum surface, heat flows efficiently from that plate through the finished floor materials and into your living space.

Because Warmboard is so conductive, we are known for using the lowest water temperatures in the radiant heat industry. Most Warmboard systems operate with water between 90º and 110º. If high resistance floor coverings such as wool carpets are desired, there is lots of room to raise water temperatures while still operating in the conservative temperature range that maintains the highest system reliability. Lower water temperatures mean lower energy bills for the life of your Warmboard home!

The importance of low thermal mass

Fast response is one of the most important characteristics of a radiant heating system. The amount of heat required by a home or an individual room changes over time and the changes can be fairly rapid. Cloud cover can clear in just a few minutes causing rapid changes in the warmth provided by the sun. The outside temperature can change significantly in just one hour due to normal daily variations. For these reasons, fast response is essential to the performance of a radiant heat system. Thermal mass, on the other hand, will cause significant delays between when heat is needed and when it is finally delivered. It is not unusual for the owners of slab-based systems to wait many hours before their homes are warm. Warmboard starts heating up within minutes of heat being called for and rapidly responds to changing needs to provide the right amount of radiant heat right when you need it.

Warmboard Brochure