SelfBuildSawyer

Thanks for your reply Dan. The tree is circa 6m from the proposed building (a chalet bungalow). I believe it is a Monterey Cyprus, but there is some debate about this. Thanks Kylus. 600mm deep trench and it bottomed onto heavy clay of density 1.94g/cm3 (soil report conducted for foundation design)... The soil make-up is this.... Stoney clay soil from 0 - 400mm deep, then a layer of very stoney clay to 550mm deep, then pure heavy clay to at least 2m deep. Tree condition is good to my untrained eye. Age estimated to be circa 40 years based on satellite images and talking to neighbours.

Hi all, I'm not from your arboriculture realm, but I have recently taken a very keen interest, read this forum to death and value your experienced views. I'm a chartered structural engineer, trying to design and build my forever home, close to an existing 17m tall conifer (in a neighbouring garden). Other planning constrains and site dimensions are going to dictate that if this build is feasible, some level of standard circular RPA encroachment will be inevitable. Historic land use and conditions (boggy ground, old hard-standing and old brick wall footings on boundary) lead me to question if the stock 12x stem dia. circle RPA was indeed realistic in this location. I have hydro-vacuumed a root investigation trench (heavy clay soil so an air spade was not going to "cut" it) to see if the roots do indeed extend into where I am proposing to locate a new building. The trench has revealed 5 singular roots, all smaller than 25mm in diameter. The building will be on pile foundations with RC slab in any case due to ground conditions, but I'm trying to avoid the LA tree officer making me raise the building, with a ventilated air gap and rain water re-directed to existing ground under slab. BS5837 guidance says that I can safely cut these sub 25mm roots.. If I were to then place a root barrier in the vacuumed trench before back-filling, would you guys see it as acceptable to redraw the RPA as a polygon of equivalent area, taking into account the new root barrier and likely real rooting spread? Obviously assuming the new RPA was reasonable with good rooting soil etc. An arb consultant will be on-board (initial site visit conducted only at the moment), but I just want to know how your community would react to such a suggestion. Will reply with more info if required. Hopefully an interesting topic in any case, and I'd welcome your views on this with regard to the incoming BS update. Thanks in advance, John