When you go in through the front door, pass through the lobby with its 'stable door' on the right and go straight into the Hall. This is about 30 feet long, 20 feet wide and 25 feet high. It is open right up to the roof, and you can see how it is built. At the ends the roof is held up on triangles of timber: the flat one straight across is called the tiebeam and the ones from its ends to the roof are called the principal rafters. However in the middle the roof is supported on a different arrangement of timbers. It is as if the middle of the tie beam had been sawn out, leaving the stub ends or hammerbeams which have carved heads on their inner ends. These are supported from below by curved braces and they in turn support vertical posts upwards from the carved heads, called hammer posts. A collar connects together the upper ends of the hammer posts, and arched braces hold the hammer posts and the collar firmly in place.

The end or tiebeam trusses and the hammerbeam trusses between them are held down the length of the hall by wallplates along the top of the walls and by purlins in the roof. The purlins have curved weatherboards to hold them rigidly in place. Then the whole structure is covered by common rafters and laths, and lastly tiled on the outside.

You will notice the honey coloured oak wood. There is not much soot in here - perhaps a little from rush or tallow candles in olden times, but not nearly enough soot for there ever to have been a cooking fire here: in any case there is neither chimney nor hole (or louvre) in the roof. So we wonder what the place was used for. It may possibly have been used as a hunting lodge for Bletchley Park nearby, but it is perhaps more likely that it was used as a manorial court house. Perhaps a junior member of the Grey family or maybe the lord's steward lived in the house, collected the rents, kept the village in order, settled disputes and carried out the various paperwork chores which seem to be the rule in any sort of organisation. In any event, Rectory Cottages is a rare survival: there are not above a dozen true hammerbeam roofs in English houses (there are more in churches). A list of the mediaeval hammerbeam roofs of England reads like a roll call of great places: Westminster Hall, Hampton Court, Eltham Palace, Dartington Hall, Chester Cathedral Refectory, the Pilgrims' Hall at Winchester, and so on until last and least you come to Rectory Cottages Bletchley - but it keeps some very distinguished cousins. In later times, the hammerbeam roof was considered a noble structure, and several Oxford and Cambridge colleges built their refectories or eating-halls with them. Even later, town halls and other buildings intended for imposing purposes have been built in the same way.