Sound Insulation – The Many Methods of Sound Reduction

In simple terms, sound insulation is reducing the sound from the source (sender) getting into a room (the receptor). There are several methods on reducing the sounds coming from these extraneous sound-makers. The receptors include theaters and recording rooms among others.

Some of the methods used include increasing the distance between the sound maker and the receptor, the use of noise barriers (either through reflection or deflection of the sound waves) and the use of damping structures like baffles or the use of anti-noise sound generators.

Also usable are acoustic quieting, noise mitigation, and noise control in limiting noise. Soundproofing can suppress the unwanted indirect sound by reflection that can cause echoes and resonances.

Methods

One way of reducing the transmission of unwanted sound is sound proofing by way of using distance and intervening objects in the sound’s path. The density of the sound decreases as it spreads out. With distance, the intensity of the sound waves becomes less and less.

Damping reduces the resonance of sound in a room by absorption or re-direction. The methods are reflection and diffusion. Absorption reduces the sound level while re-direction makes unwanted sound harmless by reducing its coherence.

During the absorption of sound, parts of the sound energy are converted into heat in the intervening object (the one that absorbs it) rather than the sound is being transmitted or reflected. The absorbing material for sound is determined by the frequency distribution of the noise.

Absorbers

An open cell rubber foam or melamine sponges absorb sound by friction within their cell structures. Throughout the broad range (medium) of frequencies, the porous open cell foams are highly effective sound absorbers.

These cell foams can absorb sound depending on the cell size, porosity, material thickness and material density, including tortuosity. The other sound absorbers include resonant panels.

The reflectors will make the sound hitting them be reflected than if the sound hits a softer medium like fiberglass. (It is used to deflect sound skyward in noisy highways caused by speeding vehicles.)

Transfers

The transfer of sound from a room into the outside happens thought mechanical ways. The vibration passes directly through the brick, woodwork and other solid structural elements. When the sound meets other elements like a wall, ceiling, floor or window (all these can act as sounding boards), the sound is amplified and heard in the second space (the outside).

Mechanical transmissions are faster and more efficient and can be readily amplified than an airborne transmission (sound released on its own) of the same initial strength. Soundproofing with the use of acoustic foam and other absorbent materials is less effective, in this case.

Another method of sound proofing is simply breaking the connection between the room that contains the sound source and the outside space. (It is called acoustic de-coupling.) This eliminates the vibration transfer in solid and in the air.

Sound insulation takes in many forms and the use of some devices. The main purpose is to break the vibrations transfer from one medium to the other (solids to air, air to solids, and solid to solid materials).  

Wall Insulation – Barrier for Heat and Cold

One of the three more important places to insulate your house is the walls. (The others would be the floor and the attic, completing the three dimensions.) When winter comes, the wall insulation will serve to hold the heat inside and make it comfortable.

Like everything else insulated, your walls won’t feel cold to the touch and would certainly keep the warmth inside for you and your family. It also prevents condensation and the following molds from forming later. The point is simply to keep comfort inside the home with the proper insulating of the walls.

Conditions

Generally, the houses that were built before 1972 usually don’t have insulation on their walls. Owners were clueless as to the type of walls they have. (Some are empty and with no insulation whatsoever.)

In summer, the insulating materials of the walls help reduce the amount of heat coming in from the walls. This helps maintain the cool atmosphere inside the house. Those walls that are facing south and west (known as “hot walls) are the ones hit by the sun and make them hot.

The heat they get will be radiated into the house in turn, and it goes on even after sundown. When these walls are insulated, the heat is reduced because the entrance into the insides of the house is reduced.

Insulation

The experts usually suggest that the insulation of the walls should be done when the house is about to be re-painted, doing the stucco again, or when it is about to be coated with texture. The rationale is that many holes are needed to be drilled onto the walls.

The holes will be properly covered during repainting or coating with texture. Also, the insulation of the wall cannot be injected from the attic or from any other part underneath the house. The holds had to be drilled on the face of the walls either from the exterior or the interior.

The work

There will be holes (2 inches each) that will be drilled on each bay and made every 16 inches across. The wall will then be injected with insulation until full and then plugged with Styrofoam. The stucco patching is applied and every patch is floated to match the standard stucco texture.

After the patches dry up in a day, the wall is primed and painted right after. Some owners want to repaint their entire house, while others would only want to color match the paint on each patch.

The drilling can be done on either side of the house (the exterior or the interior). It is best to have the house empty when doing the work from the inside. (Some would decide to do their insulation work from the exterior because of the dust.)

Insulating the exterior walls of the house is generally for thermal insulation to keep the house cooler in summer and warmer in winter. The insulation is keeping a barrier between the insides of the house and that of the outside. This is simply done through wall insulation.

Insulation – Materials for All Types

In a sentence, insulation is the prevention of having heat or sound from being transmitted from one place to the other. There are materials for these that bar one condition (heat or sound) from spreading. With the work and lifestyle today, you want to keep them out from places you want to be comfortable and peaceful.

There are many ways to do this, and mostly with the help of materials we depend on to do the job. Insulators usually use tiny pockets of air in them. The air is one very good insulating materials, and confined pockets of trapped air gives many types of thermal resistance.

Heat and cold

To control heat, the first thing that comes to people’s minds is thermal insulation. This type of insulation is found in house walls, ceilings, and floors. Also, it is usually in the outside of the house where heat is gained or lost.

The main idea is simple to keep one side of the wall warmer than the other. This usually occurs in places where the weather has extreme variations during their times of the year.

Your insulating design needs to follow the climatic pattern. If your place is constantly cold or constantly hot, you need to pattern your design accordingly.

Measurements

The thermal insulation is measured in R-values (R stands for resistance). The higher the R-value, the better the material can provide insulation.

The R value of the material itself is known as Rm, while the total R value of the construction (including all the materials in it—concrete, plasterboards, bricks, etc.) is known as the RT. Those reflective membranes with air spaces added to the system add to the RT, while the reflective material itself does not have any Rm.

Sounds

Insulating materials not only controls heat, it also controls sound. In some degrees, every type of insulating material can do both control of sound and heat.  The acoustic type is usually found in walls, ceilings, and floors.

Specialized sound proofing is done in some special applications like home theaters, recording studios and the like.

There are now acoustic insulating measures for windows, ceilings ands walls. These are for areas where outside sound can be a nuisance (busy roads, airports, train lines, etc.), there are specialized ways in keeping out the sounds from the outside environment.

Double duty

These days, some materials meant for keeping thermal heat inside a house or building from the cold outside, can also prevent sound to seep through inside. The fact is that this ability depends on so many factors.

Pitch and volume of the sound, how your house is constructed, and the general noise level of your area govern the intensity of the unwanted sound. Keeping off the noise is better inside houses between rooms and living spaces.

Materials

Batts (usually made of glasswool or rockwool) are materials with plenty of trapped air inside them will be the insulating material for heat resistance. Others include blown-in cellulose, polyurethane foam, polyester matting and reflective foil.

Actually, most of them offer different insulation properties for you to choose from for your particular needs.

House Insulation – Differences in Insulating Materials

House insulation is a necessity if they are constructed in cold countries or in places where there are extremes in heat and cold climates during the year. With the extremes in climate conditions, people cannot live in their houses in comfort, whether in heat or cold conditions.

However, people are creative enough to fight off these extreme weather conditions by way of insulation. For these houses, the insulation must be in between floors (basements and crawl spaces), between ceilings and unheated attics and inside all the exterior walls of the house.

With less than adequate insulation, the heating (or cooling) energy escapes through the walls, the ceilings and any place where heat can seep in or out. To keep the energy in, and keeping the heating costs down, the house would need to have the proper insulating material to wrap it up.

Insulation

Insulation needs are usually governed by R-values, in the materials and in the projects. The R-value of a material is the heat that passes through. Higher R-value means the insulating qualities of the material is also higher.

Insulation materials are available in blankets, batts and loose-fill. These materials that are usually available to users have their own R-values. However, each of these materials has its own unique qualities different from the others.

They also have different qualities in terms of ease of installation, flammability, and others that are over and above their R-values.

Here are some of the popular ones in use these days and the things to consider when choosing them for your insulating work in your house.

Fiberglass

This is usually the number one choice among the materials these days. They usually come in batts, in rolls and in pellets used in loose fill applications. Some of its advantages are that it is relatively inexpensive, easy to install, and is fire resistant.

It can have a better material for a good vapor barrier and it is available in an unfaced variation. Some of its downsides include the fact that it can be itchy and that it develops an odor when dampened.

Rock wool

This one offers almost identical qualities of fiberglass. It has nearly the same quality ass fiberglass, including its cost and its R-value. It can also be itchy, although it does not develop a smell when dampened.

There is a third new material that has almost the same qualities as these two and it is called earthwool. It is new in the market and people have to test it to check its favorable reviews.

Cellulose

Cellulose is also fire resistant like fiberglass and rockwool. However, its R-value is higher and it does not irritate skin like the two popular materials

It comes in rolls, batts, and loose-fill. It has a fine consistency which permits its being blown-in during installations through small openings or access holes.

Urethane

Urethane is mostly known as a foam-in type of insulation material, but it is very effective when installed properly. It has a very high R-value and it is also fire resistant. For acoustic use, it also has excellent sound-absorbing qualities.

For house insulation, the market has an excellent set of choices.