The Livable Winter Cities Association (WCA) was formed in Canada to disseminate ideas on how to make living in northern climes more enjoyable. It has become a major worldwide organization with several offshoots.
And publications. Norman Pressman’s books offer a wealth of information on home and city design for the north.
But igloos stereotypically have white roofs, don’t they? 
Black is going to be a better radiator of heat then white as far as blackbodies go. Look at the Space Shuttle or the SR-71 (which I believe may be a very dark indigo blue). If one could “see” in the far infrared region, you would immediately note that a black surface would be “brighter” then a white surface.
In the case of the Space Shuttle, the black tiles have a very thin black coating (egg-shell thickness) which will re-radiate about 90% of the heat that impinges on it while the 10% makes it way on through the shuttle (which is handled by the bulk of the tile and is about 90% void in volume.) When I was in college I had a chance to demo defective shuttle tiles (donated to us by Rockwell who was the Shuttle’s prime) at the university’s open house (Poly Royal). We would take an acetylene torch and blast the black surfaces to the point of yellow-white hot in a ~one square inch area (1100°C to 1300°C) , and by removing the flame, any emitted color would disappear in a matter of 3 - 5 seconds (if memory serves my right). You might argue that “black stuff” was conducting the heat to the insulator, but we decided to test this by aiming the flame on the “white” insulator–it melted almost immediately (which I guess show that it was a good … insulator). So that left radiation and convection as the only means of “escape”. However given the fact that an objects radiates proportional to Temp^4 (Stephan-Boltzman’s law) , a casual observation would indicate to me that convection would not be the main source of heat transfer via the shuttle tile (besides, you could feel the hot spot radiating on your face during the max temp excursion).
In the case of the SR-71, a black coating was added to the Ti surface of the plane which allowed it to run 30° cooler during its Mach 3 excursions.
Finally take identical two cups of coffee and a thermometer. Add a known amount of cream to one (taking into account the temperature and heat capacity of the cream), leave the other black. Set side by side in a controlled environment and note the temperature for each cup over time. The black cup will cool down faster then the white one.
Overall a “white” house has a poorer heat transfer ability then a “black” house all other things being equal. So painting the roof white would be the more effective.
(For those who say that the shuttle’s nose and leading edges of the wings aren’t black … the material here used is RCC (reinforce carbon carbon) which can handle temps up to 3000° F [during re-entry the shock-wave which is a few inches ahead of the RCC can hit about 10000° F!!!]. Shuttle tiles can’t handle that kind of temperature. Unfortunately, the RCC’s density is much higher relatively speaking then a regular tile so are used only for the high temperature regions.
To give you an idea of the how light the “regular” tiles are, when I first handled oneI thought somebody was pulling a joke on me–it literally looked like, felt like, [with a wee bit of grittiness], and weighed like a piece of Styrofoam with a black cap. Amazing stuff.)
Not a clear experiment. The fat or other chemicals in the cream may inhibit evaporative cooling of the coffee in that cup.