Unless I was fixin' on modeling an HO-Scale rainstorm I wouldn't worry about a roof.
From the far, far reaches of the wild, wild west I am: rtpoteet
Thanks for the responses. I was hoping to go with tar and gravel since I haven't tried one yet. Looks like I have a good opportunity here to try it.
From the picture on the Walthers site, this building has a flat or almost-flat roof. I've been using Rustoleum textured speckled black spray paint for such roofing, and I really like the results. It's high-priced for a rattle-can at the hardware store, but one can will do a lot of buildings. In this early picture, the City Classics Diner's roof uses this material, with some rust weathering powder added.
The foundation, incidentally, use a tan version of the same paint. Over in Mooseport, these buildings have a fresh coat of Rustoleum as they await some more modeling work.
It takes an iron man to play with a toy iron horse.
Top it off with the Miller Engineering REA lighted sign on the roof.
To make tar & stone roof, paint the roof with a thick coat of black paint, preferably gloss, then cover with sand and let it dry. WHen dry, pour off the excess sand for a completed roof.
Another type of roof is rolled tarpaper. This is best done brfore the roof is installed on the building. To do this get a piece of white, non-textured facial to toilet tissue. Toilet tissue works better, it has more wet strength. Paint the roof with a gray paint like Floquil Reefer Gray (or the equivlent Polyscale) or Model Master Gunship Gray. Lay the tissue into the wet paint, and paint over the tissue to let the paint soak in. Use a light touch so as not to tear the tissue. Paint a bit over the edge to the roof piece. WHen dry, use a hobby knife to trim the excess tissue from the roof edge. Using a very fine black marker, draw lines a scale 4 feet apart across the length or width of the roof. Finish by drawing lines 10 feet apart between every other row of lines; then on the alternate lines draw a line 5 feet from the edge to simulate a half length sheet and then 10 feet apart for the rest of the row.
You can see both types of roof on this deep background building I am working on
George In Midcoast Maine, 'bout halfway up the Rockland branch
Tar and stone.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
Finishing up my initial build of the Walther's REA building and wanted to detail/ dress up the roof. What type of roofing material(s) would be appropriate to model for this style of building?