This a cruck-framed hall-house dendrochronologically dated to 1508 and typical of the better class of Welsh farmhouse in the late Middle Ages. The building is divided into five bays, the lower two used for housing for cattle and horses, the centre bay serving as a work-room and the upper two comprising the open hall and a bedroom. The outside walls are timber-framed, the panels being in-filled with wattle and daubed with clay. Both the daubed panels and the timber work are limewashed as was common in the Middle Ages. The open hearth is placed in the centre of the hall, smoke from the fire escaping through the roof and the unglazed windows. Excavations in 2003 by Bill Britnell at Tŷ Draw at Llanarmon Mynydd Mawr in north Powys have done much to elucidate the relationship of the cow house with the hall of a longhouse. This is a classic three unit hall house of longhouse type. It has an open hall of two bays set between inner and outer rooms, the outer room acting as an cow byre. Dendrochrononology on the roof purlins suggest that Tŷ Draw was completed shortly after 1479/80 and it has been possible to suggest from this dating that the house was built by Hywel ap Rees. In the byre area, which was accessed by door, a series of small post holes were noted, that have been interpreted as wickerwork hurdles. These would have provided stalls for cattle which were overwintered from November to March each year. Similar evidence for stalls for cattle have been found at Tŷ Mawr and Tyddyn Llwydion in Montgomeryshire. The idea of the "Longhouse" or "Tŷ-hir" was first discussed by Iorwerth Peate in his pioneering book "The Welsh House"(1940). This was the description of a house where both people and beasts were housed together under the same roof, as portrayed in the Medieval Welsh poem the Dream of Rhonabwy. Peate thought that the Welsh Longhouse had had a long history and that it occurred in all parts of Wales. This view was challenged by Peter Smith, who had gathered a vast amount of information in his "Houses of the Welsh Countryside", published in 1975. This showed that longhouses were rarely "one-phase" buildings and often the byre had been added onto the house.