I read this online: The Porch House, in the High Street, is one of the most important houses in the village and must have belonged to a number of prosperous inhabitants over the centuries. As we see it today the house was built in the 16th and 17th centuries on to the core of an earlier house. The porch itself is apparently of the 15th century as is a cross wing on the right hand side. Until the building of a bypass in 1964 the main Trowbridge to Chippenham road was West Street, forming the cross of a T junction with the High Street and so Porch House would have occupied an important site at this junction with the main road. (I cannot understand why this states that the porch is a wing on the right hand side when it looks to me like the porch is on the left hand side. Those people are at its location, if you ask me.)
These half-timbered houses date from the medieval period. The one with the two bay windows, nearest the Red Lion, was known as the Coffee Tavern in 1905--I found a vintage photo online.
Lacock Food Store and Post Office--didn't even have time to stop in here. I was too busy taking photos of all of the historic exteriors to wonder about what might be for sale in the store.