Snapshots from the gap filling trials

I've been doing some testing of ways to solve the 'Portacabin Problem'. That is, how to eliminate, or at least reduce, the gap between the base of a building and the surrounding sidewalk.

I've been using the restored Post Office building for these tests as it's no stranger to being abused :-)

The technique so far is to place the building on a flat surface - I'm using the MDF surface of the layout table - with a piece of wax paper underneath, then carefully dab filler - I've found Deluxe Materials' Prefect Plastic Putty has worked best so far - in the gap between the foundation and the surface. After drying, the wax paper is peeled away, and the hard putty on the side walls is sanded smooth and painted to blend into the foundation wall.

Because the sidewalk is slightly off-flat compared to the layout table's surface, I then took some very fine slivers of modelling clay and worked them into a few remaining gaps. In the lead picture, the right side of the facade has clay worked in, the left doesn't and neither do the front steps. The clay improves the look, but it's tricky to get it into place and look right.

I took this picture before filling the gap with clay, and you can see the gap is still quite noticeable. Although, the unclayed side foundation wall doesn't look too bad with just the putty applied. 

I think further refining of this technique will reduce the worst offending foundations, but clearly having an extended foundation that sits into a hole in the layout is the best. For me though, I want the flexibility of arrangement that a flat sidewalk surface allows.