Most common mattress type sold is the innerspring or traditional mattress, where the support portion is made from steel coils coming in different shapes and forms. Quality of the innerspring mattress is determined by the support system – amount, type and gauge of coils and by the comfort layers on the top that provide cushioning and pressure relief. There is a huge range in quality and prices among traditional beds. Even though they look quite similar on the outside they vary greatly on the inside.
Traditional mattress consists of several layers: top, quilt or ticking layer, comfort or padding layer, coil support system, edge support. In the past innerspring mattresses were designed to work together with traditional boxsprings containing several bigger springs or tension bars for additional support. For the most part those are not used anymore and majority of modern innerspring mattresses come with solid foundations that don’t alter the feel of the mattress. Steel coils, being the essential elements of the innerspring, come in many types. The overall quality of innerspring and its support is determines by shape of the coil, gauge of the coil (thickness of wire - the lower the number, the thicker the coil) and quantity of coils. All better mattresses nowadays use independently pocketed coils providing even support, better contouring of your body, reduced motion transfer and improved durability.
The feel of the mattress comes from comfort or padding layers with premium materials like memory foam, gel foams or latex. On the very top of the mattress are quilt layers, providing final finish and breathability. High-end products will incorporate natural fibers like aloe, silk or cashmere in these top layers. The comfort or softness is determined by the amount and thickness of padding layers, and these come only on one side of the mattress. All current mattresses are one-sided and you cannot flip them. Manufacturers use words like Firm, Plush, Pillow Top to describe the comfort/softness level of particular mattress. Product line or mattress line is referred to as a group of mattresses with identical innerspring or support and different comfort levels, ranging from extra firm to very soft (there are a few exceptions using extra firm coils). Generally, softer mattresses are more expensive because of added cushioning materials.
Types of Coil System
Marshal Coilor better-known as pocketed or wrapped coil system is the newest innerspring system consisting of cylindrical coils wrapped in cloth or plastic pockets. The coil is compressed in pocket, thus providing tension at all times. Each coil is in its own pocket, working independently allowing for better conforming to the body and reducing motion transfer. Since coils are not tight together by wire there is significant decrease in unwanted sounds and squeaking. This type of support system is typically softer, made from higher gauge wire compared to tied or continuous innerspring, but on average uses more coils. Some manufacturers offer variants with extra thick wire providing very firm support and improved durability but in the expense of increased pressure on your body. Wrapped coil system is preferred for use with movable bases. The most of higher quality mattresses will have this type of coil system.
Coil-In-Coil design system is the latest innovation in spring mattresses. It is essentially a small coil with tighter smaller turns inside of bigger coil with a few larger turns. They both create one coil that is individually wrapped and bears the same benefits as Marshal Coil system. It offers a unique feel, where it reacts it two stages, first activating the bigger coil and later putting the smaller coil in action. The coils are usually bigger, made from lower gauge wire providing superior durability.
Braided Coil design uses several strands of thinner wire braded together into one coil, multiplying the strength of a single wire. It offers superior support and durability and comes with a steep price, usually offered in ultra high-end products.
Tied Coil system is made from individual coils that have a square top so they can be easily tied together by a spiral wire from left to right, process called helical lacing. Since the coils are connected they work together at all times providing very firm support but still allow for good conforming to the body. This kind of design provides extremely good durability but lacks in motion reduction. While the coils are tied together in one row, any movement on one side is transferred by this wire to the other side.
Continuous Coil system is similar to previous Tied Coil system. Its coils are made from one piece of wire and are tied together not left to right, but from the head to the foot of the mattress. This type of helical lacing provides reduced motion transfer from one to side to another but it creates more pressure on the body.
Bonnell Coil system is the oldest and least expensive system comprising of hourglass shape coils. This design offers the least amount of coils per size because the Bonnell Coil is quite wide on the top, making it the least durable. Limited number of coils causes insufficient support for an adult and also provides very bouncy and shaky feel. It would make a decent temporary mattress but definitely not suitable for long-term solution.
The number of coils in a particular system is important in determining the quality of the innerspring mattress, but it is not the only attribute you should consider. Coils design, quality and their arrangement are also critical. As a general rule, more coils of the same design equal better support and better durability. But sometimes with increased number of coils their size and their thickness decrease, thus providing softer support. Make sure you are comparing the coil count of the same system in the same size, as mentioned above, individually pocketed coil system will often have more coils than continuous coil system. The coil count of various products can vary form under 400 to over 1000 in queen size. As a rule of thumb, you shouldn’t consider a mattress for an adult with less than 600 coils in queen size.
As a general rule, more coils equal better quality innerspring, but not all coils are made the same. To determine quality of the coil we need to consider factors like type of steel used, size of the coil and gauge of the coil. Obviously most of the time you won’t be able to find all these attributes even though they should be provided to you by all manufacturers to help you make a good decision.
Type of steel used in coils production is obviously very important in determining the durability of the coils and their ability to keep their shape and spring for a certain time. It is nearly impossible to find this information about majority of products out there. Lately, a few brands started to advertise their use of titanium or carbon in their springs. Don’t get fooled by their marketing. They use only a fraction of these high-end metals in the steel where it doesn’t have any impact on it’s quality.
Size of the coil is another attribute that determines the quality of the whole innerspring. The coils are made from the steel wires. Longer wire allows for a taller coil with more compacted turns. Depending on the gauge, taller coils with more turns will provide better support and last longer.
Gauge of the coil is a measurement of diameter/thickness of the wire the coil was made from. The lower the number, the thicker the coil. Coil gauge varies from product to product and generally it correlates with coil count. Typically you fit less thicker coils in the same size mattress. The gauge can fluctuate from under 13 for a very firm coil to above 16 for a very soft coil. When comparing different gauges, make sure the coil system and coil count is similar.
Benefits of Innerspring Mattress
Traditional “bouncy” feel
Construction of Memory Foam Mattress
Traditional mattress consists of several layers: top, quilt or ticking layer, comfort or padding layer, coil support system, edge support. Steel coils, being the essential elements of the innerspring, come in many types – Bonnell coil, countinuous coil, tied coil and individually wrapped coil. The overall quality of innerspring and its support is determines by type of the coil, gauge of the coil (thickness of wire - the lower the number, the thicker the coil) and quantity of coils. All better mattresses nowadays use independently pocketed coils providing even support, better contouring of your body, reduced motion transfer and improved durability.
To utilize the entire surface of the mattress and prevent rolling off the bed some manufacturers reinforce the sides of the mattress. Typically they incorporate walls of extra dense foam on both sides or all around the mattress. This design allows for keeping the body in the mattress instead of rolling off. Some manufacturers prefer not to use this type of edge construction because, as they claim, they favor consistent and uniform feel across the mattress.
The feel of the mattress comes from comfort or padding layers made from polyurethane or premium materials like memory foam, gel foams or latex. The layers come in different thicknesses and shapes and are stacked in certain order to provide a particular feel. They determine the overall softness or comfort of the mattress, what you feel when you push your hand on the top. The amount of padding also determines the model name of the product – firm, plush, pillow top…
On the very top of the mattress are quilt or ticking layers, providing final finish and breathability. Kind of like an insulation layer. High-end products will incorporate natural fibers like aloe, silk or cashmere in these top layers. By federal law all mattresses must be treated with fire retardant materials.
In the past innerspring mattresses were designed to work together with traditional boxsprings containing several bigger springs or tension bars for additional support. For the most part those are not used anymore and majority of modern innerspring mattresses come with solid foundations that don’t alter the feel of the mattress.
Innerspring Mattress Warranty
As the construction varies from model to model so does the warranty. Be extremely diligent to learn about the warranty of any given product. Warranties are design to protect consumer against manufacturer’s defects for certain period of time, and majority innerspring mattress warranties protect customers against excessive sagging. Excessive sagging is typically referred to as an indentation/imprint/depression greater than 1.5”. Most warranties start with a full mattress replacement for an initial period of time, and change to a limited (pro-rated) warranty as years go by. While comparing innerspring mattress warranties, you can find full replacement warranties for as little as 2 years and as high as 10 years, with overall warranty duration up to 25 years.
After you have decided that traditional innerspring mattress is the way to go, you still have plenty of work left in deciding on which one. First important decision is to pick the comfort or softness level that works the best. Try all models in one product line of a brand you are considering, starting with the medium soft one and than moving on to soft and firm. Don’t rush it and spend great amount of time comparing and going back and forth. Ones you pick your preference, either extra firm, firm, plush, pillow top or euro top compare the same comfort level with different brands of product lines. By eliminating the products you didn’t like or those that didn’t fit your budget you end up with the one that fits your bill.
The innerspring is the engine of the mattress. Find out all the specs available. The number of coils in a particular system is important in determining the quality of the innerspring mattress, but it is not the only attribute you should consider. Coils design, quality and their arrangement are also critical. As a general rule, more coils of the same design and gauge equal better support and better durability. Number of coils and their gauge are the most common characteristics of innerspring mattress that help compare quality of different products.
Besides innerspring padding layers can make or break a great mattress. Read about the benefits of different materials and make a list of those that are important to you. You will always pay more for premium materials like memory foam or latex, so make sure it is there in sufficient quantity. Natural fibers like wool, silk or cashmere on the top of the mattress are desirable, because they are more breathable, but are obviously more expensive. Try to avoid polyester, which doesn’t breath as well. The finish of the mattress is a matter of personal preference, stretch covers are nice because they breathe better and don’t leave creases. Don’t get swayed by the pretty floral design on top, it will be covered by a mattress pad and won’t make any difference at all.
Be aware of different warranties, most of them covering indentations larger than 1 1/2” over certain period of time. Find out how long is the mattress fully covered, and if the warranty is pro-rated, know what portion of the replacement cost you will be responsible for. Make sure you ask your store about exchange/return options and exchange/return costs. Read the fine print of the exchange/return policy before you place an order.
Always ask for a special financing offers or the incentive for not using one. Some retailers charge extra delivery and old mattress removal fees and those can add substantially to the final amount. Always ask for free gifts with a mattress purchase, it is always nice to get free pillows, mattress protector and set of sheets.