Roofs and Structures
Roof system made of paired rafters
well attested
Rafter construction, Rafter roof, Rafters
What is rafter construction?
Rafter roof construction is a system of paired rafters that join at the top and rest on walls or under-rafter crowns. Battens are fixed to the rafters, and the roof covering is fixed to the battens.
It is one of the most common traditional roof constructions in living houses and many farm buildings. According to VLE, rafters can be supported or hanging: two supported rafters form a rafter pair whose tops are joined by the ridge beam, while a hanging rafter pair is tied below by a tie beam, so it rests only on the outer walls and has no internal supports; rafters are most often made from sawn timber, and elements are joined with notches, sometimes nailed.
Rafters and pitch
The angle of the rafters determines roof pitch. The pitch depends on the covering: straw and reed need sufficient steepness, while shingles or split shingles require another structural solution.
Widely projecting rafter ends protect walls from rain. This is especially important for a log building.
Čiukurinis and hipped roofs
A simple gable roof needs a clear system of rafter pairs. Čiukurinis, hipped, or half-hipped roofs require additional edges and end rafters.
Roof form therefore always has a structural cost: the more complex the silhouette, the more joints and craftsmanship are needed.
Restoration importance
In an old building, rafters often preserve traces of the maker's work: hewing, marks, joints, and old battens. They should be replaced only after understanding loads and damage.
An improperly changed roof pitch or batten rhythm can spoil the whole proportion of the building.
