Boiler construction having a boiler pressure body support system

A boiler construction comprising:

• a boiler pressure body having a bottom and a roof at a height H from the bottom;
• at least four planar watertube walls forming a polygonal horizontal cross section having at least four corner sections;
• a rigid support steel structure, the boiler pressure body being supported to the rigid support steel structure at a height between the bottom and the roof of the boiler pressure body;
• and
• a corresponding vertical corner column attached exteriorly to at least four of the at least four corner sections at a height region between the bottom and roof of the boiler pressure body, wherein vertical loads of the boiler pressure body are balanced solely by the corresponding vertical corner columns by supporting each of the vertical corner columns to the rigid support steel structure at a height from 0.1 H to 0.9 H from the bottom of the boiler pressure body.