Sofa Bed Mattress Buying Guide
Step 1. Get the size right by taking width, length and height measurements of your sofa bed mechanism.While it may appear to be an odd place to start, selecting the correct size replacement mattress is essential if you want to be happy about your purchase. Choosing a size too big may not allow the mechanism to work correctly; and choosing a size too small may affect how the sofa feels when you sit on it while the mechanism and mattress are folded up inside the sofa. Also, an important fact to bear in mind is that hide-a-bed mattresses do not come in standard sizes. This is so important to remember that it’s worth repeating: sofa bed mattresses do not come in standard twin, full, queen or super queen sizes. That being said:
a. Determine the WidthTypical widths, as measured across your body when lying down on the mattress, can vary as follows: – Twin mattresses: 24-38 inches – Full size mattresses: 39-54 inches – Queen sofa bed mattresses: 55-60 inches – Super queen mattresses: 61-65 inches
b. Determine the LengthMattress lengths, measured from above your head to below your toes when lying down, typically vary from 68-74 inches. Therefore, when you need to determine the correct size for your replacement, you should measure the actual metal frame, not the mattress that came with the sofa. Also, you should measure the frame on the inside of the metal tubing, and round down to the next inch. (For example, 68-3/4 inches between the inside of the top and bottom of the frame’s tubing, would round down to 68 inches in Length).
c. Determine the Thickness (or mattress Height)Determining the thickness or height that your hide-a-bed mechanism will accept can be done with the help of the illustration below. To make sure that a 5 inch mattress can fit in your mechanism, measure the distance between the top and bottom of the mechanism at the crease of your old mattress while it is folded inside your mechanism. You will need approximately 10 inches, (see the red lines in the illustration below,) to accommodate a 5 inch thick mattress. Otherwise, a measurement of just over 8 inches between the red lines would mean that your sofa sleeper mechanism is made to accommodate a 4 inch thick sofa replacement bed mattress. A correctly sized mattress is critical, and can mean the difference between having a comfortable sofa bed and an uncomfortable one; whether you’re using it as a couch for sitting when the mechanism is folded up, or a bed for sleeping when the mechanism is fully opened. Additionally, incorrect mattress sizing may keep the mechanism from functioning properly, and reduce its useable life.
Step 2. Choose the type and quality of the sofa bed mattress.Most sofa bed mechanisms accommodate a 4 inch thick mattress, and some accommodate a 5 inch thick one. Most of us are accustomed to sleeping on our regular beds, where the mattress typically measure between 8 to 20 inches thick. Quality in a 4 or 5 inch thick hide-a-bed mattress is determined by the following factors: firmness, support and durability. You might have noticed that there are many types of sofa bed mattresses: inner-spring, foam, memory foam, gel, “gel infused” memory foam, inflatable air systems and latex. While all these are great materials when used properly in the construction of an 8 inch or an extra thick mattress, not all might be the best choice in a 4-5 inch thick couch mattress. Let’s look at the specifics:
Inner-spring sofa mattressesInner springs are rarely used in high quality and comfortable sleeper sofa replacement mattresses. The main reason behind this is that due to the limits of the couch mattress thickness, not enough turns can put into the coils to offer adequate support. In other words, there simply isn’t enough room for the inner springs to “float” before they fully compress.(See the illustration below, which compares a high quality spring with a poor quality one.) What do we mean by fully compress? Full compression occurs when the top of the mattress, where you sleep, pushes as far as it can go toward the bottom. When this happens, the person laying on the sofa bed mattress will most definitely feel some of the structural components of both the mattress (inner springs) and the mechanism (bars). With certainty, they will feel incredibly uncomfortable.
For the reasons mentioned above, we do not recommend inner spring mattresses as sleeper sofa replacement mattresses. However, if you have already decided to purchase an inner-spring couch mattress, we would like you to have a look at some specifics you should consider on this page.
Foam sofa bed mattresses
Density of any material is a measurement of how much a given volume of material actually weighs. For foam mattress cores, the standard measurement is pounds per cubic foot. When choosing a sofa bed mattress made from foam, the best quality mattresses have a support core with a foam density from 1.8 to 2.5 pounds per cubic foot.
Another important property of any foam is its firmness. A mattress made of marshmallows will feel much different than one made of feathers. The feathers are much softer than the marshmallows. For mattress foam, this firmness is actually measured in units called Indentation Force Deflection, or IFD for short. This property is an indication of how firm the foam feels, and how much give there will be when weight is put on top of the foam. The higher the IFD, the firmer the foam. Firm foams, made from high compression material, have an IFD in the range of 40-50, while softer, medium compression, foams typically have an IFD in the range of 20-30.