On a given blueprint, 1 inch = 16 feet. 1. The average dimension for such couches is 95 inches by 95 inches or 98 inches by 98 inches with depths varying from 37 inches to 40 inches. For a king sleeper sofa you’ll find the dimensions ranging from 84″ to 92″ with a mattress width of 74″ to 76″. The average depth of such sofas is typically 37 inches to 40 inches. Standard dimensions of a sectional with a chaise. MATH MS. SUE. If the dimensions of the bedroom on the blueprint are 0.75 inches × 1.5 inches, what are its actual measurements 16 ft × 32 ft 12 ft × 24 ft 16 ft × 24 ft 12 ft × 32 ft . 2-person sofa: 50″ seating width (does not include width of the arms). Sectional with chaise is one of the most popular models in the sectional sofa. Key dimensions: The main dimension you need to concern yourself with when choosing a sofa by how many people can sit in it is the width of the seating area. The length of a piece of paper is 8.5 inches. If you’re thinking bigger is better, then the next size up – the Queen, is available ranging from 75″ to 96″ inches with a mattress width of 58″ to 62″. King Sleeper Sofa Dimensions. 4-person sofa: 90″ seating width (not including sofa arms). 3-person sofa: 78″ seating width (not including arms). Queen Sleeper Sofa Dimensions.