Sofa beds: building a specification for your project
An architect and designer’s guide to sofa beds: opening dimensions, seating and sleeping comfort, mattresses, upholstery and delivery access.
| Model | Mattress width | Overall width |
|---|---|---|
| Eze | 140 | 177 |
| Mabillon | 140 | 190 |
| Alaska | 140 | 182 |
These values refer to the configurations documented on this site. Width alone does not establish suitability: compare opening depth and sleeping specification too.
Define two different uses
A sofa bed needs to work as both a sofa and a bed. Start with daytime seating, overnight occupancy and opening frequency. For regular sleeping, try the mattress and the conversion process in person. In an occasional guest setting, also assess seat depth, back support and the sofa’s everyday footprint. A model name or mattress width alone is not a specification.
Separate mattress size from furniture size
Sleeping width is not overall sofa width: arms, the back and the mechanism affect the footprint. Request the drawing for the selected configuration and mark the closed sofa, open bed and operating space. Include the coffee table, rug, doors and drawers. Check where the person stands while opening it, as well as where the bed ends up.
Assess the mattress as part of the system
Identify the mattress type, dimensions and options approved for that mechanism. A thicker mattress is not automatically more suitable, and a replacement may affect closing. Assess comfort with the intended users, the support beneath it and the manufacturer’s bedding instructions. In a multi-room project, record the tested mattress so delivery matches the approved specification.
Upholstery, care and delivery access
Choose upholstery around actual use and care instructions. Ask which covers can be removed and which components can be replaced separately. Check packaging dimensions, permitted disassembly and the entire delivery route from street to room. Clearing the building entrance does not mean clearing the lift or corridor turn. Agree on dismantling and reassembly with the supplier in advance.
Double sofa bed or chair bed?
Start with the number of sleepers and required sleeping surface, then consider seating capacity. A chair bed does not necessarily need less opening depth than a double sofa bed: with some mechanisms, the main difference is width. For each configuration, request overall width, closed depth, open depth and mattress dimensions. This allows a single-guest option to be assessed without relying on a photograph or product name.
A sofa bed schedule for contractor and developer projects
Organise the selection by apartment or room type: model and configuration, mattress size, upholstery code, quantity and delivery floor. Identify mirrored apartments and rooms with different access routes separately. Before a bulk order, review a representative configuration with the architect or interior designer and the delivery route with the site team. Confirm pricing and delivery dates against the actual specification and quantity.
What to record in the plan and specification
| Topic | Information to gather |
|---|---|
| Seating and sleeping | Sofa configuration, intended users and approved mattress dimensions. |
| Opening envelope | Closed and open width and depth, plus the movement during conversion. |
| Upholstery and service | Fabric code, colour, cleaning instructions and replaceable covers or parts. |
| Delivery | Packaging dimensions, access route and agreed assembly scope. |
Checklist before approving the specification
Seating and sleeping were assessed in the requested configuration.
A place for the table and cushions is shown when the bed opens.
Mattress and upholstery codes are included in the quotation.
Intended use and service terms have been confirmed for the project.
Questions from the planning process
Is every sofa bed suitable for nightly use?
Do not decide from the category name alone. Assess the model, mattress, use instructions and comfort for the intended sleeper. Try the system before selecting it for regular sleeping.
Can a sofa be specified by mattress size alone?
No. You also need external closed and open dimensions, the operating envelope, arm configuration and delivery access information.
How much room does a chair bed need?
Use the external dimensions of the chair in both closed and open positions, not just the mattress size. Allow operating and circulation space too. A narrower piece does not necessarily have a smaller opening depth; check the drawing for the exact configuration.
This guide addresses planning considerations. Dimensions, loads and installation details depend on the approved model and specification and coordination with the project professionals.