| 摘要 |
A constructional element in the form of a roofing panel or board (10) has insulation material (15) such as foam in the interior thereof between oppositely facing first and second faces (11, 12). Retention means, for example channel-section bars (16), are held in position in the insulation material (15), for the reception, in use, of fixing screws (20) to fix a waterproof layer (19) to one of the faces (11, 12), each fastened screw terminating in the interior of the insulation material (15) so as not to extend through the other of the faces. The retention means are such as to distribute therethrough any load on the fixing screws attempting to release them. |
