A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
A stair 1 for a roof. The roof is pitched and includes sheet material SM and at least two screws BS by which the sheet material is screwed down. The at least two screws have screw heads atop the sheet material and screw bodies passing 5 though the sheet material. The stair includes a tread portion 3 and at least one riser portion 5. The at least one riser portion has at least two screw-engaging portions 7 for engaging the at least two screws to support the stair on the roof. 3a 3a• 5a b .t t BS 13a 3a
A stair 1 for a roof. The roof is pitched and includes sheet material SM and at least two screws BS by which the sheet material is screwed down. The at least two screws have screw heads atop the sheet material and screw bodies passing 5 though the sheet material. The stair includes a tread portion 3 and at least one riser portion 5. The at least one riser portion has at least two screw-engaging portions 7 for engaging the at least two screws to support the stair on the roof. 3a 3a• 5a b .t t BS 13a 3a
Roof safety device
SAFATLI HAFEZ (author)
2019-03-21
Patent
Electronic Resource
English