First, there are only two mainstream installation methods in the market, one is the pasting technology with (fireproof) wood plywood as the backing, and the other is the dry hanging method with keel as the bottom; Most of the advertising signs at the door are pasted. Obviously, the questioner chose the way of dry hanging.

Secondly, if the dry hanging operation is selected and the construction area is relatively large, then the triangular iron keel is basically welded piece by piece, and it is impossible to hoist after welding on the ground. Of course, when welding parts, hanging wires will be carried out to ensure the verticality and smoothness of the facade.

Thirdly, when the galvanized square pipe or aluminum square pipe is used as the skeleton, the fixing method of aluminum-plastic plate can be bonded with double-sided adhesive or structural adhesive in advance, but this method will not stick firmly if there is no wooden splint as the backing. When there is wind pressure inside and outside, it loses viscosity for a long time, especially after the adhesive ages, the aluminum-plastic board outside is easy to fall off, which has potential safety hazards.

Fourth, the questioner is actually very clear, mainly leaving gaps. We suggest leaving more vertical seams and less flat seams. The practice of three sides is often to extend a small part on the side, leaving a gap on the side more beautiful.