This remarkably complete c1600, 4-bay, stone and timber-frame corn-barn has 2-tier square-framed side walls a cruck and truss roof with stone-end walls. It has wide, opposed doorways to a threshing-bay against a lower-end cattle- bay with loft over. It is unusual in having a mixture of crucks and trusses supporting the present slate roof. Against each end wall is a tie-beam truss, which is seated on the wall-plate and pegged to the purlins. Thes end-walls wrap around extending slightly into the side walls, for extra stabilty. This appears to be an experimental period when formerly framed end walls were first built in stone, whilst trusses were also used occasionally, allthough crucks were still thought necessary.
There are two cruck trusses, one open between the two store-bays with only a collar and one with a tie-beam and collar situated between the threshing-bay and the cattle-bay. The upper side of the threshing-bay has a principal-post and tie-beam collar truss. The common rafters are supported on 3 pairs of side-purlins and a diagonal set ridge-piece.
The open cruck has spurs which are lapped and angle-pegged into the blades between the wall stud which is open mouthed, so that the notched spur is dropped over, locking it in place. A similar method was used at New-house barn in Llanfetherine.
The size of the building is almost identical to a 4-bay cruck-framed barn at Sleath Farm, allthough that has cattle under its two lower bays and is on sloping ground.
Visited, Geoff Ward, 19/08/2010.

[ADDITIONAL] A late sixteenth-century cruck- and box-framed four-bay barn with stone gable ends. Summary of tree-ring dating results reported in Vernacular Architecture 42 (2011):

x. LLANVETHERINE, Croft Farm Barn (SO 37968 17829) Felling date: Spring 1581
Purlin 1539; Post 1556(h/s); Tie beam 1580(39?C). Site Masters 1472-1539 clv07 (t = 7.8 SWANHS; 6.2 WALES97; 6.2 TYTHEBG); 1453-1556 clv05 (t = 5.1 LYDBURY3; 4.9 lsy1; 4.8 DENBY5); 1442-1580 clv06 (t = 6.1 SOMRST04; 5.6 SARUMBP6; 5.5 SWANHS).
A remarkably complete four-bay, stone and timber-framed corn-barn. The barn has two-tier square-framed side walls on a stone plinth with stone end walls. The threshing floor with wide, opposed doorways is located alongside a lower-end lofted cattle bay. The barn is unusual in having a combination of crucks (two) with one box-framed truss and tie-beam truss set against the gables. The two cruck trusses are interestingly different: one open between the two store-bays with only a collar and the other with a tie-beam and collar situated between the threshing-bay and the cattle-bay. The upper side of the threshing-bay has a box-framed truss with jowelled post. This range must be regarded as a barn of transitional type retaining cruck-trusses but anticipating the mixed box-framed and stone-walled barns characteristic of C17th Monmouthshire noted by Fox and Raglan. Plan and account in NMRW. Dating commissioned by RCAHMW at the suggestion of theVillage AliveTrust. (R.F. SUGGETT/RCAHMW/JULY 2011)