Community: Building Code Questions

Article 38 requires you to filter incoming air to residential units close to the highway and high traffic areas with MERV 13 filtration. That said, the building has electric heat due to the climate. The engineer spec'd fantech inline fans with custom MERV 13 box filters intercepting the supply duct, then dumping into the apartments. I worry that this will be too inefficient, dumping cool air into the apartment at night and keeping the temperatures low, forcing tenants to use the electric heating. That said, I would propose a spot ERV with MERV 13 filtration.

I have a flat roof and my contractor built a cedar board floating deck. the area is 16'x20' range and he made into 4 section, 16'x5' each. the boards are tight fit(no space) and also tight fit to the edge wood board( the wood board sit on top is metal capping). the nails are all sunken under the wood surface. One winter with snow/rain, I had to shelve the snow off the roof since the ice/water sit on the cedar boards. there was a leak(this roof did not have leak before the new deck). I tried to find out where the leak was, but the boards were all frozen together, like a big ice block.

When installing rigid foam in an unfinished crawlspace, what is needed to have it comply with the fire code? Foam board to be installed on inside of foundation wall and on the underside of joists?

I am researching energy efficiency objectives in codes and regulations, in Canada and the US. The first Canadian residential insulation value tables appeared in the (provincial) 1975 Ontario Building Code. I know that California's 1978 "Title 24" introduced even broader energy conservation measures. However, I do not know what US jurisdiction (state or city) was the first to publish insulation value tables for new homes, in a building code. I would appreciate your suggestions ...