Why do old American bridges have roofs?
Why do old American bridges have roofs? Most of America's covered bridges were built between 1825 and 1875. By the 1870s, most bridges were covered at the time of construction. The original reason for the cover was to protect the bridge's trusses and decks from snow and rain, preventing decay and rot.
When did they stop building covered bridges?
About 14,000 covered bridges have been built in the United States, mostly in the years 1825 to 1875. The first documented was the Permanent Bridge, completed in 1805 to span the Schuylkill River in Philadelphia. However, most other early examples of covered bridges do not appear until the 1820s.
Why did they stop building covered bridges?
In the mid-1800s, the development of cheaper wrought iron and cast iron led to metal rather than timber trusses. Metal structures did not need protection from the elements, so they no longer needed to be covered.
Why are Amish bridges covered?
Today there are around 200 covered bridges, that remain in the state of Pennsylvania, and that includes 28 just in Lancaster County! While covered bridges are sometimes called “kissing bridges” the reason for the roofs is to protect the bridge's truss structure from all the weather conditions.