What is the standard size for ventilation ducts that can be used by players to walk in? I mean like the kind featured in Turbine next to the spawn. The map I am creating features these, and I want to get the proportions right.
128 external width, 96 internal, and thus walls 16 thick. This is how Hydro has them which is (I think) the only valve map with them. I vaguely recall Turbine having thinner walls, and maybe being slightly smaller inside. But there you have it
Just make sure your inside walls are 96 units and Boojum noted, the width doesn't matter. Also try to make sure your LENGTH is only multiple of 96, to keep textures synced together, otherwise if you're a perfectionist it'll drive you MAD.
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