Question:
Our current roof surface is that silvered tar coating. It's leaking, and will be repaired / replaced over the next few weeks. I would like to do some container gardening and telescope viewing up there - is there anything I can say to the roofers or landlord that would make my desires easy to accommodate?
I don't know about Yankee codes but the problem with that over here is the gap between what will clearly be fire and building codes. In the real world if you make sure the weight is distributed (eg marine ply under footings making sure no sharp nasties etc) all should be well, but since that generally won't comply with manufacturers guarantee, installers guarantee or building codes around roof terraces it could be kinder to leave the landlord plausible deniability.
Thanks, GinandTonic, you are correct.
Translation: a sheathing grade plywood substrata under the roofing material will distribute weight better than the old tongue in groove sheathing that roofs were made from pre-WWII, and he screws will not pop out like the old nails will. But most roofing materials are not warrantied for use as walking surfaces or terraces, GinandTonic is saying, I believe, don't tell your landlord if you decide to do rooftop gardening, because it will void his warranty.
Flat roofs are normally designed for lower loads than balconies. Once you install a handrail people will use it as a balcony.
Correct.
Thanks to all for the input. Keep it coming.
Now, since we are both New Yorkers, I can be more specific: the fact that it is a silver-tar roof means that it is likely a coating over tar paper -- and therefore not designed for walking in general. Tar paper is not designed for foot traffic. Add to that a 1920s building will have a tongue-in-groove roof -- which will have nail pop-out problems. However, NYC building codes require flat roofs to be walkable for purposes of firefighters -- in the same vein as skylights having to be either wire glass (you know, the glass blown around a wire cage) or at least fitted with wire mesh cages to prevent firefighters from falling when they land on them. So, your roof is at least passable for a walking surface. However, I do not advise trying to place containers on a roof like that for long period of time. The weight plus water and eventual rain accumulation will cause eventual damage on a tar roof.
The only roof material I have seen used out of the box, so to speak, for walking surfaces is a hard fiberglass membrane -- very expensive and a lot of labor. One of my organization's offices has a deck designed over a roof and the simple solution there was to make is a wooden deck on top of a EPDM (rubber) roof, on top of runners that are placed on a thick rubber slip -- also very expensive (it took us a year to raise the money and do the work o the entire building.)
So, if the roof would hold up, the deck over a rubber roof would be okay -- or a hard fiberglass membrane.
Ask your landlord about what they are planning. If it is just a roof repair ont he silver tar roof, and not a new roof, forget the gardening, but you may steal a moment or two stargazing. If the landlord plans on a new roof, say you would like to do some container gardening and star-gazing -- what would that take?
