Debunking the Myth of Laminated Panels

Myth: “Laminated” or “Slab” panels are inferior to urethane because they are glued to the skins to hold the panel together. Therefore, these types of panels are not considered as durable and are thought to come loose within a short period of time.

Truth: For over 40 years walk-ins have been manufactured by either gluing insulation to metal skins (laminated) or pouring urethane (foamed-in-place) between two metal skins.  Contrary to most beliefs, both systems provide equal performance in adhesion if applied correctly.  This is important because in walk-ins the structural strength of the unit is dependent on this adhesion performance.  When metal skins are glued or foamed to insulation a composite panel is created.  This created panel performs much like a steel I-beam. I-beams by design are very strong for their weight and are used in building structures that need a lot of strength without the weight, such as skyscrapers. A steel I-beam is two flanges of steel connected and separated by a center steel web.  In a walk-in panel, the two flanges are light gauge metal skins and the web is the foam insulation.  All I-beams lose their strength if the flanges separate from the web. If the I-beams separate, skyscrapers would collapse. This is similar to walk-ins that could fail if the skins separate from the foam insulation.

A Matter of Insulation: Acquisition vs. Lifetime Savings

Your cold storage equipment may be one of the most important choices you make. A significant amount of costs are associated with your walk-in. Before you purchase, make sure you consider the entire lifecycle of the walk-in instead of just the acquisition price.

The two main elements that effect energy and cost savings while running a walk-in are the refrigeration and insulation.  To get the optimal results from your refrigeration it must be sized correctly taking in consideration the size of box, if it is a cooler or freezer, and what will be stored inside. (There are many other factors that are considered when sizing refrigeration.) Insulation is the key to energy savings because it is responsible for holding the cool temperature in the box so the refrigeration does not have to work overtime. Insulation quality is measured by R-value; the resistance to heat flow through an object. Since EISA was implemented January 1, 2009, all walk-in manufactures are required to have an R-value of R-25 for coolers and R-32 for freezers. Now that all manufacturers follow the same requirements, the performance of the insulation is what differentiates the walk-in.

The two common types of insulation used are polyurethane and extruded polystyrene.  Each type of insulation brings with it strengths and weaknesses that must be evaluated for each individual application.

Insulation Strength Weakness
Extruded Polystyrene Starts with a high R-value. Smaller cell structure. Resists moisture absorption. Closed cell structure. Out gases some. Over time, R-value decreases minimally.
Polyurethane Starts with a high R-value.  Closed cell structure. Out gases more. Over time, R-value decreases steadily. Is susceptible to moisture infiltration.

U.S. Cooler uses both insulations. Through experience and research, U.S. Cooler believes extruded polystyrene is the best insulation for the walls, ceiling, and floors of coolers and freezers. Polyurethane is better to insulate the doors of their walk-ins. According to a study performed by the U.S. Corps of Engineers, they found that over a five year period extruded polystyrene retains 75% of its R-value while polyurethane retains 25%.¹  This is one reason why U.S. Cooler believes extruded polystyrene provides the most value and the best option for walk-in insulation.

Polyurethane & Extruded Polystyrene walk-in insulation
Polyurethane & Extruded Polystyrene

U.S. Cooler Saves Customers Money with Energy Efficient Walk-ins

stacked walk-in panels
Extruded polystyrene panels for walk-ins.
Most walk-in coolers and freezers are purchased based upon the initial cost. What many fail to realize is that operational costs can dig deep into consumers’ pockets. U.S. Cooler is giving the Cold Storage Industry an energy efficient option by manufacturing walk-ins with extruded polystyrene insulation.

Extruded polystyrene is the most efficient insulation available on the market. Over time, extruded polystyrene resists moisture while other insulations start absorbing it. One must consider a real life application to understand moisture absorption.

Freezers normally operate at -10° F inside, but may have an exterior temperature of up to 95° F or even more. With the extreme difference in temperatures, the insulation is vulnerable to retaining moisture in the structural voids. When water starts collecting inside walk-in insulation, the R-value drops and moisture inside the insulation starts to freeze.

r-retentions1

When moisture is absorbed and R-values start to decrease, refrigeration systems start working harder and longer to make up for the heat transferring into the walk-in. A refrigeration system working overtime means higher energy bills. By using extruded polystyrene, consumers can save that money.

Extruded polystyrene is unique; the insulation is a closed-cell product, meaning the cells of the material are so tightly packed together that moisture has a difficult time penetrating, which is optimal for moisture resistance and keeps the R-value from decreasing.

Using studies performed by the U.S. Army Corps of Engineers (CREEL), U.S. Cooler demonstrated extruded polystyrene saved consumers over $5,000 in energy costs over the first five years of operation. The savings again are due to extruded polystyrene’s ability to resist moisture and to retain its R-value better than other insulators.

energy-savings2

When buying and selling walk-ins, consider more than the initial cost of the walk-in-consider energy costs. Educate yourself about how to save money; to find out more about extruded polystyrene and energy savings, call 800.521.2665 or visit www.uscooler.com.

Cooler Insulation- Extruded Polystyrene Vs. Polyurethane

U.S. Cooler manufactures walk-in coolers and freezers employing both Polyurethane and Extruded Polystyrene. Through testing and years of experience we maintain that extruded polystyrene insulation is superior for use in walk-in coolers and freezers. Polystyrene has many characteristics that prove it to be the best insulation material for walk-ins. The two main insulating foams found in walk-ins are Extruded Polystyrene and Polyurethane. Each insulation has differentiating characteristics and should be optimized for the specific application.

Polystyrene is a dense closed-cell structure that is very resistant to moisture and holds its R-Value longer than other competing insulations found in walk-ins, such as Polyurethane. This allows less water infiltration in the insulation, which in turn saves energy and money. When water starts seeping into the insulation’s pores, the R-value drops dramatically causing the refrigeration to work harder to hold its respective temperature. Refrigeration working overtime means higher energy bills. Polystyrene is less water vapor permeable; therefore, water vapor does not infiltrate through the material as quickly or easily as it does other insulating materials.Using studies performed by the U.S. Army Corps of Engineers (CRREL), U.S. Cooler demonstrated extruded polystyrene saved consumers over $5,000 in energy costs over the first five years of operation. The savings again are due to extruded polystyrene’s ability to resist moisture and to retain its R-value better than other insulators.

Polystyrene used in walk-in coolers and freezers is made from “at least 20% pre-consumer recycled polystyrene.” (Owens Corning, Technical Bulletin: Recycle Content Claims Must be Reliable and Verifiable) Polystyrene found in walk-ins is also 100% recyclable. Manufacturing companies that produce these insulation materials, reproduce the resources in new insulation material. Alternatively, it is important to note that Polyurethane is produced from chemicals and is not made from any recycled materials nor can it be recycled or reused.

Polystyrene in walk-in coolers and freezers is the most cost effective and environmentally friendly insulation used in walk-ins today. Not only is polystyrene in walk-ins made with recycled materials and is 100% recyclable but it is energy efficient and can save a great deal of money in energy costs and reduce carbon footprint over the life-cycle of the walk-in.

Meeting 2009 EISA Walk-in Cooler & Freezer Standards

The federal government’s EISA (Energy Independence & Security Act) standards went into effect Jan. 1st, 2009. This act was intended to improve energy efficiency within the refrigeration industry as well as many other industries. AHRI reports there have been some concerns since there are no enforcement mechanism or standard testing methods built into the act; non-compliant walk-in manufacturers will stand to benefit. These manufacturers will be able to beat compliant competitors on price (due to the lower input costs of their non-regulation walk-ins). Be sure that when buying a walk-in, you check to make sure they are EISA compliant.

The AHRI (Air-Conditioning, Heating, and Refrigeration Institute) is trying to raise awareness about what this act mandates among distributors, installers, and consumers. They have created a checklist of the standards walk-in coolers & freezers are required to meet that can be found at ACHR The News. Use this checklist to ensure the walk-in unit you are about to purchase meets the EISA standards.