Yes, our motorways (freeways) were mostly built as six lanes, which when first built in the late 50's early 60's seemed like such a vast amount of pavement for so little traffic. Fortunately or unfortunately, depending on how you look at it, that space didn't remain empty for long. Once section, the M5 to the south of Birmingham, was built with only four lanes to save money but was later widened to six lanes at a much greater cost than it would have been to build it with six lanes from the outset. If our rural freeways had been built with just four lanes, like most of the US, I dread to think how they would cope with todays traffic.
Many miles of six lane freeway have been widened to eight lanes over the years. This picture shows work commencing on such a stretch, and traffic jams are the norm, especially in construction zones. The problem with widening our roads is the bridges were often built wide enough to accomodate the existing traffic lanes which means adding extra lanes requires a new wider bridge or losing the shoulder at each bridge although unusally in this picture the bridges are able to take an extra lane in each direction without losing the shoulder. This is rare though. Even the medians are only about 6 foot wide so our right of way is extremely narrow compared to North America.

Another construction zone is visible here. This is the M6 freeway which provides the only decent route along the northwest of England. When this road is blocked the alternatives are the existing roads which pass through all the towns and villages and a traffic jam in these towns is usually the sign that there's been an accident on the freeway. If I remember correctly, the congestion on the right of the picture was caused by a minor fender bender which because of the construction, the three lanes were shifted to use the shoulder so any stranded vehicles will block one of the lanes causing tailbacks which within a few minutes can stretch back several miles.
