Looking back to semi-truck history, the driver’s fatigue has always been the main cause of accident deaths on the road.
To overcome that issue, truck drivers stopped at hotels to rest.
Unfortunately, that option ended up being too expensive and time-consuming for truck drivers and they continued looking into ways to sleep in their trucks. That lasted until two things happened.
First, the major truck manufacturers noticed a truck driver's need for sleeper compartments, and, shortly after that, they began developing tractor-trailer sleeper cabs.
Second, around 1950, Federal Laws limited the number of hours that a driver could spend on the road.
Today, modern trucks have internet access, satellite television, and electricity for cooking.
Some sleeper cabs are so luxurious that they provide drivers with a home-like feeling.
But it wasn't always like that.
Below, you’ll find how the semi-truck sleeper cabins evolved through history.
Sleeper cabins evolvement
For the first time, sleeping berths came into use in the early 1920s.
They were uncomfortable and living in a sleeper cab like that was unsafe. They were called coffins.
Still, sleeper berths allowed team drivers to take on longer routes by using the formula “one driver is sleeping while the other one is driving”.
That ability added to the semi-truck cab allowed truck drivers to spend months on the road.
Since then, team drivers began making requests to truck manufacturers for larger sleeping cabins.
Initially, truck manufacturers developed sleepers of 18 to 24 inches long without any comfort in mind. Later, they improved their sleepers to 36 to 48 inches long with long-haul drivers in mind.
Today, modern truck sleepers may vary in size from 36 inches to the massive 230 inches.
Since 2000, approximately 70% of the new trucks manufactured in the US included sleeper berths.
But, the first sleepers were also considered a "death trap", which were also known as coffin sleepers.
What are coffin sleepers
Coffin sleepers were very small sleeper compartments where the driver could rest.
From within these coffin sleepers, the off-duty driver had no direct access to the on-duty driver. You had to get out of the truck and get inside the coffin sleeper from an outside door.
I was able to find pictures of three types of coffin sleeper that you can see below.
1. Coffin sleeper under trailer



This type of coffin sleeper was mounted under the trailer.
These were not the safest coffins because the road debris, CO poisoning, and a lack of crash protection was affecting it.
2. Coffin sleeper behind the cab

Another type of coffin sleeper was the one mounted behind the cab of the truck and which was leveled with the top of the cab.
Though the configuration of this coffin type is similar to the modern sleeper, the main difference is that there was no direct access from the cab into the sleeper.
3. Coffin sleeper in the nose of the trailer


The first legitimate sleeper truck
When it comes to figuring out what is the first truck company releasing sleeper cabs, a few sources state that, 1953, Freightliner creates the first overhead sleeper cab.
But, in a 2013 year Facebook post, Kenworth Truck company states that, in 1933, Kenworth became the first company to offer a sleeper cab.

After that, sleeper cabs evolved to this by the seventies….

And now ...

If you can afford, you can also have semi trucks with big sleepers.

If you want to find out more about sleepers, check out this sleeper cab guide.