World Library  
Flag as Inappropriate
Email this Article

Sofa bed

Article Id: WHEBN0003316859
Reproduction Date:

Title: Sofa bed  
Author: World Heritage Encyclopedia
Language: English
Subject: Simmons Bedding Company, Bedding, Canopy bed, Bamboo wife, Hospital bed
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Sofa bed

A couch unfolded into a bed

A sofa bed or sofa-bed, (in the US often sofabed, hide-a-bed, bed-couch or sleeper-sofa), typically is a sofa or couch which has underneath its seating cushions a metal frame and thin mattress that can be unfolded or opened up to make a bed. A futon differs from a sofabed, although sofa beds using futon mattresses are common.

Sofa beds can be found not just in many styles, but many sizes as well. They are categorized accordingly, from Chair Sleepers (cot size bed) to Queen Sleepers. Almost all sofa beds contain the standard bar and canvas mechanism seen for years, however a few new lines can be found with alternative mechanisms.

Sofa beds are usually three-person couches. However sofa beds that are two-person couches are also available. These types of sofa beds are known as loveseat sleepers. They are known as loveseats since the smaller size means one needs to be comfortable with how close they will be to the person next to them.

Sofa bed mattresses

Although most sofa beds use a queen short mattress measuring 60"x72", other common sizes include 58"x72", 54"x72", and 52"x72". The average sofa bed mattress thickness is 4.5", thus being half as thick as a good standard mattress. Sofa mattresses can be produced out of many different materials, the majority on the market being made of springs or foam.

Spring sofa mattress

Although springs can make a satisfactory sofa bed mattress, the following aspects have to be considered regarding a spring sofa mattress:

  • Free length represents the overall length of a spring when no load is applied.
  • Solid height is the length of a compression, when the spring has been deflected enough to allow each adjacent coil to touch each other.
  • Working length represents the difference between the free length and the solid height.
  • Active coils is the number of coils that are free to deflect under load, i.e. the total number of coils minus the number of closed coils forming the ends is a measure of the spring quality. The more active coils a mattress has, the less working length it has, which means that the springs are the less likely to deteriorate.
  • Hydrogen embrittlement represents the hydrogen absorbed in electroplating of carbon steels causing the spring material to become brittle, leading to cracking and spring failure. Plated springs are a problem, and unplated springs are more likely to rust. Plastic coating is an alternative, but that’s extremely expensive.
  • The best springs are stress relieved, which means that the springs were treated at a temperature so as to relieve stresses. Not going through such a procedure might cause mattress failure. Unfortunately, many mattress springs are not stress relieved because it is expensive.

Foam sofa mattress

Quality foam sofa bed mattresses compress as needed, the foam acting like an infinite number of springs. A high quality foam gives better support, molds to the body and snaps back to shape. Consider the following factors of a high quality sofa bed mattress:

  • Density is a measurement of the pounds of polyurethane foam per cubic foot. High density foams can be made very soft, whereas low density foams can be made very firm.
  • Indentation force deflection (IFD) is the measure of the foam’s support, representing the pounds of force required to indent a foam sample by a specified percentage of its original thickness. Support is the foam’s ability to "push back" against your body weight, and prevent the foam from "bottoming out" on the frame or base.
  • Foam durability, flex fatigue and compression set are other terms related to foam performance.

Pocket-coil mattress

Pocket-coil mattresses are generally higher quality than spring or foam mattresses. Each coil is encased in its own pocket, allowing the mattress to keep its shape over time while also providing more sleep support. Pocket-coil mattresses are thicker than standard sofa bed mattresses, starting from 7" and going up to 10" for a premium product. The high-quality support provided eliminates the need for extra cushioning, allowing the mattress to become the seat of the sofa. This has resulted in a new style of sofa bed that doesn't require its mattress to be folded

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 



Copyright © World Library Foundation. All rights reserved. eBooks from World Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.