▁door ' s ▁hardware . ▁ ▁St ave - core ▁– ▁Cons ists ▁of ▁wooden ▁sl ats ▁stack ed ▁upon ▁one ▁another ▁in ▁a ▁manner ▁similar ▁to ▁a ▁board ▁& ▁b atten ▁door ▁( though ▁the ▁sl ats ▁are ▁usually ▁th inner ) ▁or ▁the ▁wooden - block ▁h ollow - core ▁( except ▁that ▁the ▁space ▁is ▁entirely ▁filled ). ▁ ▁Sol id - core ▁– ▁Can ▁consist ▁of ▁low - dens ity ▁particle ▁board ▁or ▁fo am ▁used ▁to ▁completely ▁fill ▁the ▁space ▁within ▁the ▁door . ▁Sol id - core ▁flush ▁doors ▁( es pecially ▁fo am - core ▁ones ) ▁are ▁commonly ▁used ▁as ▁exterior ▁doors ▁because ▁they ▁provide ▁more ▁ins ulation ▁and ▁strength . ▁ ▁Sk in ▁– ▁The ▁front ▁and ▁back ▁faces ▁of ▁the ▁door ▁are ▁covered ▁with ▁H DF ▁/ ▁M DF ▁sk ins . ▁ ▁Sw ing ▁direction ▁ ▁Do or ▁sw ings ▁ ▁For ▁most ▁of ▁the ▁world ▁, ▁door ▁sw ings , ▁or ▁hand ing , ▁are ▁determined ▁while ▁standing ▁on ▁the ▁outside ▁or ▁less ▁secure ▁side ▁of ▁the ▁door ▁while ▁facing ▁the ▁door ▁( i . e ., ▁standing ▁on ▁the ▁side ▁requiring ▁a ▁key ▁to ▁open , ▁going ▁from ▁outside ▁to ▁inside , ▁or ▁from ▁public ▁to ▁private ). ▁ ▁It ▁is ▁especially ▁important ▁to ▁get ▁the ▁hand ▁and ▁swing ▁correct ▁on ▁exterior ▁doors , ▁as ▁the ▁trans om ▁is ▁usually ▁s loped ▁and ▁se aled ▁to ▁resist ▁water ▁entry , ▁and ▁to ▁properly ▁d rain . ▁In ▁some ▁custom ▁mill