Akontaabu a ɛfa nnua a wɔde ayɛ nnua no kɛse ne n’afã horow ho
Kyerɛ nsusuwii ahorow a wɔhwehwɛ wɔ milimita mu
X - ofie no trɛw
Y - ɔdan atifi sorokɔ
C - overhang kɛse
Z - kwan a ɛda kyerɛwpon no ano kosi saw no mfiase
B - Rafter Trɛw
mmoa nwoma
Wɔrentumi nyɛ ɔdan atifi adan a wɔmfa nnua nhyɛ mu.
Sɛ wɔde gable roof structure di dwuma a, ɛho hia sɛ wobu rafters no nsusuwii, anim a wɔatwa ne groove no ho akontaa.
Wɔayɛ rafter akontaabu nhyehyɛe no ama eyi.
Sɛnea ofie no trɛw kyerɛ no, wobu ɔsorokɔ fi mfiase kosi ɔdan no atifi a ɛyɛ den ne nea ɛwɔ soro no tɛtrɛtɛ, dua no tenten, kwan a ɛda ɔdan no ano no ntam.
Dwumadi no nso bɛtwe dua no ho mfonini a ɛwɔ nsusuwii ahorow. Eyi so bɛba mfaso titiriw ama wɔn a wosi gyinae sɛ wɔde wɔn ankasa nsa bɛyɛ nnua a wɔde ayɛ nnua no.