How do you weather a roof?

Model Railroader General Discussion (Model Railroader)
1

I’m working on an Atlas roundhouse kit. With paint, flour and Dull-coat I’ve got the walls looking pretty good, but the roof pieces are just large pieces of flat gray plastic with very little relief to them. They need texture as well as some color variation. Dull-coat will help, but what other ways to people use to weather a flat roof?

2

Try posting on www.modeltrainsweathered.com , there are some expert weatherers there that could give you some great advice.

3

If it’s perfectly flat, I use fine ballast for simulate a gravel roof.

If it has some pitch, I’ve used tissue paper, and craft paint, to simulate a rolled roof.

Or you could paint the roof dark gray, and use black to mark out panels, like a tarred roof.

Nick

4

Cut a fine grit sandpaper into slabs and glue them onto the grey panels. Something just above emery paper should do, say 200 grit and higher. Use black, and then you could model green moss in the shaded north-facing shadowed area, and along seams where airborne dirt might foster other moss growth.

5

Now this is just me, but I would paint the roof some other color. How many grey roofs do you see? Once it is a different color, you can use grey to weather it as grey is the color of dirt.

Also look at what is going on. If you have a stack or vent where smoke escapes you are going to have black carbon build-up and when it washes down, streaks of black and possibly even puddles of black. fF you have a spot where steam escapes, you are going to have rust.

Look, think, observe.

6

First I spray the flat roof with primer. Then I use an acrylic black similar to Polly S Grimy Black. I don’t thin it at all. I then take a large brush and swab it on the roof the way a real roofer would spread hot tar. With some roof details like vents, ac units, water tanks etc. this creates realistic effect with minimal effort. My feeling is you want your roof not to attract attention so a passable result is all I’m after. A perfectly uniform color flat roof looks artificial and will draw the eye. Brush painting with a thick paint creates a litte texture and gets rid of that plastic look.

7

http://www.rolleiman.com/trains/clinic1p33.html

You can view the entire clinic here…

http://www.rolleiman.com/trains/clinic1.html

Dialup warning, lots of larger photos… Takes me 2 or 3 minutes per to open each page…

Good luck,
Jeff

8

It is just you…[:)] Around Long Island at least, grey is definitely the choice for flat roofs, and many peaked roofs too (various shades of course, from a light grey [my house] to very dark grey [the commercial building roofs I can see from my attic]); black and derivations there of (off-black? well, really really dark grey, but we’ll say black) are the next most popular, and then various dark reds and browns. Blues/greens are not popular (actually, I don’t remember seeing any, even on fast food outlets - they seem to favor light browns and beiges…and even that’s only on the false roof/fascia - the real (flat part) roof is usually dark grey)
Well, here and there on public buildings/religious buildings you come across copper or gold gilding, and when clean those babies really do shine in the sunlight (when not… well then the you finally get those light blues and greens…)

9

I read the title and thought about buildings, while it was loading I thought “Will he mean car roofs”? … but my original answer still applies.

Weathering begins with several things:-
(in no particular order)

Original colour / texture
Things that land on it (dust / soot / bird droppings… rain
Things that run off of it (streaks)
Damage that gets done to it
Wear and Tear
Repairs
Flaking
Holes / Patches (new / different materials)
Things that grow on it

For just buildings…

Things left on it… tools, ladders, stored stuff, paint/mastic cans
puddles
washed away gravel where water flows from downpipes (and overflows from water tanks)
Washing lines / plant pots / greenhouses / bird cages / people doing Tai Chi (or whatever it’s called) / sunbathers / people “chilling”
The list’s endless!

and don’t forget down pipes / drains

You might think fist about customising it a little…
maybe…

add skylights / smokestacks / water tanks / cellphone arials (Did the earlier loco radio systems have base stations or boosters)?
Quite a lot of industrial roofs have fixed access in the form of caged fixed ladders and wooden walkboards usually on metal frames/brackets. This especially applies where there are tanks etc on the roof… when it may only go to the tank(house).

I posted some arial pics of loco facilities recently… these may give you some ideas.

have Fun!