Environmental Design Solutions Limited (EDSL) was formed in 1989 to commercially develop Tas Software. EDSL sells Tas software and consultancy services using Tas. EDSL believe that the mixing of development, consultancy and software support leads to a focused software product, with quality support available to end users.

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The Simulation and The Reality








The Simulation

The new, naturally ventilated office at the Building Research Establishment, Garston, England, illustrates the ability of Tas to accurately predict the key features of building performance, such as natural ventilation, thermal mass and solar shading.













Simulated 30 days internal air temperature for the south-facing office area and design air temperature (design weather July 1995)










The Reality

The building at Garston was first occupied in the summer of 1997. Monitored data shows internal temperatures well below those outside with no mechanical cooling. This building successfully demonstrates the strong influence that building structure, solar protection and good ventilation can have on indoor comfort.



Using simplified calculations, such as the admittance method,
the peak summer temperature is predicted to be~35°C, some 10°C above
the monitored peak of 25°C.









Monitored 30 days internal air temperature for south-facing office area and external air temperature (monitored July 1997)









Does your current design software overestimate summer heat gains and tell you that design options are not feasible when you know that competitors have already made it work?

Well... those competitors are probably using building simulation for design analysis. If they are, there’s a 90% probability they’re using Tas Building Designer.