Best Insulation for Radiant Floor Heat

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Every winter, we rely on our heaters for warmth. Despite dense air from outside, floors are notorious for releasing cold, even during summer. Many people use radiant floor heating systems as a solution.

For that reason, this article will educate you on insulation importance and the best insulation for radiant floor heat.

Many homeowners complain of their radiant floor heating systems being inefficient. But honestly speaking, these systems are very efficient, unless you wrongly install them.

For instance, if you don’t use the best insulation method, you’ll always have problems with radiant floor heating. The problems occur due to heat loss within the floor instead of rising to the room.

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Understanding Radiant Floor Heat System

Radiant floor heat system has an option of electric cables, water pipes, or warm air passages that run beneath or on the floor to heat the floor surface.

The system heats the floor through thermal radiation. Heat first diffuses through the floor rather than the surrounding air. Afterward, it reaches the nearby objects and then spreads around the room.

The mechanism used to transfer heat from the floor to the entire room is known as thermal radiation. Radiation transmits thermal energy to the air inside the room by electromagnetic waves.

Electromagnetic waves occur as a result of periodic changes in the magnetic fields.

The electromagnetic waves carry potential energy, and when they come into contact with air or objects, they release the energy.

The energy is in the form of heat, the warmth you enjoy when you turn on the system during winter.

What Are the Types of Radiant Floor Heating Systems?

Before you learn about insulation methods, it’s good to understand the three types of radiant floor heat systems. Let’s dive in;

1. Air Based Radiant Floor Heating System

The system uses electricity or solar to heat and pump air through pipes installed beneath or on the floor surface. However, the method is rarely used because air cannot hold enough heat for faster radiation.

As that’s the case, the method is regarded as the most expensive, and many homeowners prefer other options.

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2. Electric Radiant Floor Heating System

The electric radiant floor heating system uses thin electric cables that carry electric current along the floor. They are regarded best for small rooms like the bathroom because the floors are rarely raised.

Secondly, electricity may not be cost-effective to run them in large rooms.

Another cable option is an electric mat usually laid beneath joist floors.

Despite electricity being expensive, you can save several dollars with these systems. After switching off the system, many homeowners have enjoyed the warmth from the floor for 8 to 10 hours before switching on.

Luckily, when the daytime temperature is high, or you’re doing much cooking in the house, they can be more economical.

3. Hydronic Radiant Floor Heating System

Hydronic radiant floor heating is the most common among homes. The method is cheaper because homeowners have a variety of heating methods to choose from. You may use electricity, coal, wood, kerosene, or gas.

Secondly, hot water can retain heat for longer periods.

Heated water is pumped from the boiler through tubing laid in patterns beneath the floor surface. Zoning valves control water flow, and the thermostats enhance temperature uniformity.

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Choosing the Best Insulation for Radiant Floor Heat

Insulators enhance radiant floor heater efficiency by preventing heat loss through the floor. Here are reliable insulators you may choose;

1. Foam Sheets

For radiant floor heat insulation under concrete, foam sheets are the best. They provide the best radiant pipe resting platform and prevent heat from escaping into the concrete floor.

Once the pipes are laid on the foam sheets, the concrete is laid on top. Afterward, you can do your desired floor design.

Concrete and foam sheets combination send enough warmth to heat a room faster.  

2. Smart Shield Insulators

The best insulation for joist radiant floor heating is a Smart shield insulator. They are thin enough for the joist floors. 

They are used with aluminum heat transfer fins for efficiency as described below;

First, the pipes are installed beneath the subfloor, and the aluminum heat transfer fins are fixed along the pipes a foot apart.

Secondly, the smart shield cover is installed beneath the pipes from one end to the other between the joist spaces.

Third, lay the R-15 insulator on the floor surface under the joist spaces. As an alternative to the R-15 insulator, you can use spray foam.

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3. REHAU Tacker Board

They are best for hydronic radiant floor heating. The hydronic pipes are embedded in a slab that transfers heat.

They are made of polystyrene board with fabric polyethylene plastic sheet reinforced. The insulator serves the three purposes named below;

  • Thermal insulation
  • Soundproof
  • Providing piping platform and support
  • Insulation Panels

Radiant heat insulation panels are used with concrete pads where the system uses polystyrene tubing (PEX) to circulate water. The panels prevent the pipes from getting into contact with the floor.

FAQs on Floor Insulation

Do I Need Insulation Under Heated Floor?

You need good insulation under your heated floor for best outcomes. Read the benefits of a good insulator;

It saves you money by preventing heat loss within the floor.
It enhances faster heating because all heat is directed upwards.
It prevents moisture from the heated air setting on the floor due to uniform heat distribution.

Is Radiant Floor Heating Enough to Heat a House?

The radiant floor heating is enough to heat your room with the best insulation. The system focuses on sending all the heat to the rooms hence faster heating. You can read further benefits below;

Good for allergic people because they don’t blow dust or pollen.
All heat is radiated to the floor, which is notorious for making many houses cold.
It’s quiet because no moving parts.
Cost-effective because there is no unnecessary heat loss.
Uniform temperature distributed by insulators.

Does Radiant Heat Crack Concrete?

Radiant tubing is flexible enough to withstand heat. As such, no need to worry about your concrete floor if you purchased from a trusted dealer. However, quality insulation for radiant floor heat is the key if you need warmth and still save energy. 

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