Technical Booklet R Access to and Use of Buildings·Page 30·4.14
Effective clear width for altered buildings or material change of use
Where a building is altered or undergoes a material change of use and the standard door width cannot be achieved, a reduced effective clear width as specified in Table 4.1 column (4) is permitted.
Where a building is to be altered or undergo a material change of use and the provisions of paragraph 4.13 cannot be achieved, an internal door may contain a leaf which provides an effective clear width of not less than that given in column (4) of Table 4.1.
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