Radiant Barrier Insulation Services, San Bernardino, Moreno Vall
Radiant barrier is a highly reflective material, typically made of aluminium, which blocks the transfer of radiant heat by reflecting it away from its surface offering a permanent way to reduce your monthly utility costs. Radiant barrier foil insulation systems BLOCK radiant heat energy instead of absorbing it like fiberglass insulation. Because this foil insulation is unaffected by humidity, it will continue to perform at a consistent level no matter how humid the seasonal climate.
A radiant barrier insulation system is a layer of reinforced aluminium foil facing an airspace inside a building.
How Does Radiant Barrier Work?
In order to fully understand how a radiant barrier works and how one can benefit you, the following concepts and radiant barrier information will enhance your understanding.
Heat Transfer Methods
Heat moves from one location to another in three different ways: conduction, convection, and radiation.
Conduction: this method of heat transfer occurs when two solid objects touch each other. The heat is transferred between the two objects via molecular motion. For example, if your hand touches the surface of a light bulb, the heat from the glass will be transferred to your hand.
Convection: heat that moves through fluids, such as water, rising heated air, or steam is doing so by the convection. In air, convection results in rising heated air causing the cooler air to drop to the floor. This creates what is called a free convection loop. One can create their own convection loop by using a fan to circulate the air in a room. This creates what is called a forced convection loop.
Radiation: heat that is transferred by infrared waves is called radiation. These rays are invisible to the naked eye and are not affected by air flow. Stepping out into the sun on a hot day, you will feel your skin heat up from the heat radiating from the sun. And you will still feel these heat rays regardless of how windy it is outside. Radiation is the transfer of heat from a warmer object across an air space (or vacuum) to a colder surface and all objects radiate some of their heat in varying degrees from 0% to 100% whether it be the surface of a car that’s been sitting in the sun or an electric stovetop burner.
How Conventional Insulation Works
Most people are familiar with traditional insulating materials such as fiberglass, cellulose, Styrofoam, and rock wool. These products absorb or slow down convective and conductive heat transfers to insulate. These types of insulation do not BLOCK heat – only slow it down. Therefore, after a period of time, 100% of the heat absorbed would eventually transfer through the insulation. The rate in which this heat eventually transfers through an insulation material is the material’s R-Value.
Fiberglass and blown-in cellulose insulation are manufactured with air spaces inside designed to reduce heat conduction through the material. They also restrict heat transfer by convection by trapping air flows and lowering air circulation.
How Radiant Barrier Works
A radiant barrier is designed to BLOCK (reflect) radiant heat energy, unlike traditional insulations that are designed to slow it down by absorbing it. A radiant barrier can also REDUCE heat transfer caused by convection by blocking convective air flow.
How does a radiant barrier reflect/BLOCK radiant heat?
There are two physical properties of aluminium that a radiant barrier utilizes to reduce the transfer of radiant heat.
Reflectivity = The natural reflectivity property of a reflective surface facing a heat source across an air
space allows the aluminium to REFLECT radiant heat back to the direction from which it came.
Emissivity = All materials have emissivity’s ranging from 0% to 100%. The lower the emittance percentage of a material, the lower the amount of radiant heat radiated from its surface. The naturally low emissivity property of a reflective surface facing an air space results in very low emittance of heat from itself; it does not radiate much of its own heat from itself.
A Radiant barrier REFLECTs radiant heat that strikes its surface across an air space from a heat source and conversely, it EMITs very little radiant heat from its surface across an air space opposite a heat source.
Why Radiant Barriers REQUIRE An Air Space
No matter how you plan to install a radiant barrier, it MUST have at least one air space of at least 3/4 of an inch on either side to be effective at BLOCKING radiant heat. It does NOT matter which side of the radiant barrier the airspace is located. The purpose of the airspace is to prevent conductive heat transfer.
If a radiant barrier does not have at least ONE air space on either side of it, heat will conduct from the surface touching the radiant barrier, through the barrier, and then transfer to the next surface touching the radiant barrier on the opposite side therefore, giving you no protection against the heat you intend to block.
Therefore, as long as the airspace requirement is achieved, a radiant barrier will be effective at BLOCKING radiant heat regardless of your application, i.e. interior/exterior walls, siding, roofing and attic locations, etc.
What Happens When No Air Space Exists
Because a radiant barrier requires an air space on at least one side of itself to be able to BLOCK radiant heat, a radiant barrier CANNOT be installed directly underneath roofing materials where no air space exists.
For example, if you install a radiant barrier on top of roof decking between the felt paper and asphalt shingles, it will NOT provide any benefits as the radiant heat would be transferred through the shingles, through the felt to the radiant barrier, and through the roof decking into the attic space.
A radiant barrier can be effective with an asphalt shingle roof ONLY when installed inside the attic either to the underside of the roof decking or to the underside of the roof rafters. In these attic space applications, there is an air space below the radiant barrier. It is the existence of a single air space that eliminates, almost entirely, the pass-through of radiant heat.
Blocking Radiant Heat Transfers in a Home
All building surfaces include roofs, ceilings, and even conventional fiberglass and blown-in insulation radiate heat in varying degrees. Radiant heat from the sun strikes the outer surfaces of roofs and walls and is absorbed causing building surfaces to heat up. This absorbed heat moves through the material (via conduction) to the opposite side and is then radiated from itself into attics and living spaces increasing the temperatures inside the building.
Installing a radiant barrier is a MUST to combat the major form of heat transfer (radiant) that is currently not being controlled by your conventional insulation.
How Radiant Barrier Benefits You
Radiant barriers reflect/BLOCK 95-97% of the radiant heat transfer and when installed in an attic space, they can result in a reduction of attic temperature below the radiant barrier of up to 30 degrees. Lowering the temperatures above living space ceilings provides a significant benefit by reducing air conditioning loads and energy usage. Radiant barrier can:
Reduce heat transfer from attic to living spaces by 16-42%,
Extend the life of air conditioning unit,
Increase the comfort level of a home, and
Reduce monthly cooling bills up to 17%.