When calculating the size of soakaway that would be required for a set roof area, should you calculate the actual roof area (i.e. the steeper the roof, the greater the surface area), or do you use the building's gross floor area (i.e. irrespective of the roof pitch)?
Furthermore, our site slopes down towards the road, so installing a soakaway in the back garden would involve some almighty deep trenches to be dug to provide the correct fall for pipes to carry rainwater from the front downpipes. We can quite easily site the soakaway in the front garden, it would be just over 5 metres from the house, but only a metre or so from the road. Can we position a soakaway this close to a highway?
Furthermore, our site slopes down towards the road, so installing a soakaway in the back garden would involve some almighty deep trenches to be dug to provide the correct fall for pipes to carry rainwater from the front downpipes. We can quite easily site the soakaway in the front garden, it would be just over 5 metres from the house, but only a metre or so from the road. Can we position a soakaway this close to a highway?