There's currently nothing in the city of Pittsburgh code that tells you what to do if you want to plant flowers, ferns or grass on your roof, but that may change.

Legislation city Councilman William Peduto introduced today would set rules for the growing "green roof" trend. The proposed ordinance -- part of a six-pack of environmental bills the councilman is introducing today -- would require consultation with a structural engineer if the soil on a green roof is going to be more than 5 inches deep, or if the pressure from the soil and plants is to exceed 15 pounds per square foot.

Also introduced today was legislation that would tighten recycling rules, demanding, for instance, recycling containers on all floors of municipal, institutional and commercial establishments.

It also would set a new scale of punishments for not recycling. Residents would get a warning for a first violation, followed by fines of as much as $50, $100 and $500 for subsequent failures to recycle -- a modest easing of the current fine scale.

Apartment building owners would get no warnings, and a $100 fine the first time, followed by a $1,000 hit -- double the current charge for a repeat violation.

Commercial, institutional and municipal establishments would face fines of as much as $1,000 for first violations, followed by $5,000 charges if it happens again, which matches the existing code.

The legislation also would empower building inspectors and police to join environmental service workers in enforcing mandatory recycling, and require that the city start pairing sidewalk trash cans with recycling receptacles.

The other bills would require that the city conduct energy savings audits on all of its own buildings every 10 years; create a Sustainability Commission to advance environmentally friendly policies; codify the existing staff position of sustainability coordinator; and tell the mayor to work on guidelines for buying environmentally friendly products and services.

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