Metal structures

Frame: 80×80 or 100×100 posts, 40×20 trusses, 1–1.5 m rafter spacing. Profiled sheet or polycarbonate roof. ~25–40 kg/m² steel for a light canopy.

Sliding: cantilever beam, rollers, counterweight footing — 1.5× opening width. Swing — hinges on 100×100 posts minimum, lock and latch in-frame.

Snow load — regional norm 70–180 kg/m² in Ukraine. Wind load for tall fences. Span deflection ≤ 1/200. 1.3–1.5 safety factor — don't save on steel.

Load-bearing welds — full penetration or double-sided. Tee joints with gussets. Check: visual + hammer tap. Critical joints — X-ray/UT by pros.

Clean → metal primer → 2 coats enamel. Underground posts — waterproofing + concrete, else they rot at grade in 5–7 years.

Spans >6 m, house load-bearing beams, elements above people (facade canopies) — engineered design and certified welder. A mistake here isn't 'reweld' — it's a collapse.