Mortuary Service Administration Act Article 26

Public cemeteries shall be divided in burial regions according to the terrain. Each region shall have several tomb bases delineated and numbered. Each tomb base area shall not exceed eight square meters. However, for burials with more than two coffins, four feet is allowed in order to gain space for each increased coffin. The land area of each urn (tank) for ash burials shall not exceed 0.36 square meters.To conserve land use, special municipality and county (city) competent authorities are allowed to reduce the land area mentioned in the preceding paragraph with considerations of the actual need.
中文原文 殯葬管理條例第26條
公墓內應依地形劃分墓區,每區內劃定若干墓基,編定墓基號次,每一墓基面積不得超過八平方公尺。
但二棺以上合葬者,每增加一棺,墓基得放寬四平方公尺。
其屬埋藏骨灰者,每一骨灰盒(罐)用地面積不得超過零點三六平方公尺。
直轄市、縣(市)主管機關為節約土地利用,得考量實際需要,酌減前項面積。

English translation for reference only; the Chinese text prevails. Not legal advice.