Firstly I used an aerosol can of soot black from Modelmates to really darken down the roof and to take the shine off all the side walls. I've previously used their mud brown weathering spray to good effect and the soot black was equally useful. The only problem with using an aerosol can is that it can be difficult to direct accurately, so I applied it as a mist above the model allowing it to fall like rain. To make this a little more realistic I did this mostly from the position of the chimney so the directionality would be right.
Once I was happy with the soot, I then set about touching up small areas using a dark brown chalk. I've had a box of chalks for as long as I can remember (I have a feeling they might have belonged to my Dad) and I lightly scraped a little of chalk onto a piece of paper, from where I applied it with a paintbrush. I mostly focused on the sides of the roof which were still too clean until I was fairly happy with how it looked, although a few areas were still a little too clean. Fortunately at this point the post arrived. I've recently subscribed to the British Railway Modelling magazine and whilst the magazine hasn't arrived yet, my free gift has. The free gift was a set of Humbrol weathering powders so I attacked the building with some smoke and dark earth to give the final result you can see here, which I think looks a lot more realistic. Now I just have to get on with some landscaping to give it a proper home.
