Whether you need to convert a guest bedroom with two beds into a room with one larger bed or you desire a different mattress firmness, it is simple to create a king-size bed from two smaller twin beds. A king mattress already sits on top of two twin box springs inside of a bed frame. Two twin mattresses and box springs will fit easily into the same bed frame to create a larger bed.

Standard Bed Sizes

A standard twin bed is 39 inches wide and 75 inches long; a standard king bed is 76 inches wide and 80 inches long. Attaching two twin beds will give you a king size bed 2 inches wider than the standard size king and 5 inches shorter. It is not ideal, but it will give you a larger bed that two adults can share reasonably well.

Versatility

Twin beds are often less expensive than king mattresses. Purchasing two twins and converting them can be more affordable for some people. Other couples find it helpful to have separate mattresses with different levels of firmness; pushing two twins together will give them the king bed they prefer and the restful night's sleep they need.

Converter Belts

There are two ways to convert twin beds into king beds. Both methods will require a twin-to-king converter belt, available at most home goods stores. Most metal bed frames are adjustable to fit a range of bed sizes. If yours expands to a king, set up the bed by expanding the frame to fit the two box springs with the two mattresses. Close the gap between the mattresses using the converter belt and a king-size mattress pad. If your frame won't expand or you need flexibility and want to be able to use either two twins or one king, simply push the two twin bed frames together when a king is needed. Hold the mattresses together with the converter belt.

Sheets and Bedding