The charity, which is organised by New York-based British architect Cameron Sinclair, originally set a target of $100,000.
But this target has now been blown away - Sinclair has announced that it has now passed the $500,000 mark.
This vast figure was given a large helping hand by the Boston Society of Architects, which is understood to have contributed a 'very significant sum'.
There were also many other smaller-scale fundraising efforts which, according to Sinclair, 'were all aimed at one goal. Creating a small good thing out of a very large tragedy.'
The cash will largely go towards the charity's work in the Sri Lankan coastal village of Kirinda, where it is drawing up plans for homes, hospitals and other civic buildings.
These proposals - which were based on a consultation period in January and February - have recently won local planning permission.