> The difficulty of adding more ventilation is the lack of space above ground to put new ventilation shafts. This is always going to be a problem for the older

> The difficulty of adding more ventilation is the lack of space above ground to put new ventilation shafts. This is always going to be a problem for the older tube tunnels except on rare occasions when a surface development takes place at just the right location and agreements can be made to include a shaft down to the Underground Sounds like we need to knock down a few houses. This isn't unreasonable for critical infrastructure. Also sounds like giving people free ground source heat pumps along the tube line would be best - they would be pumping out the heat thats in the clay. The article talk about a scheme, but this needs to be done at scale