A Way Forward (or a better Protocol)

1. A Way Forward(or a better Protocol) P.G. Biddle

2. Determining which remedy: • Persistent deficit (significant heave) • Underpin with full anti-heave precautions • Seasonal drying (predominantly) • Vegetation control • Fell • Prune • Root control • Underpin (if tree of sufficient value) P.G. Biddle

3. Information required: • Seasonal or Persistent deficit • Which vegetation is involved. • If vegetation control, proof of whether it has been effective. • Extent and duration of heave. • Extent of movement for partial underpinning. • Appropriate level of proof for situation. • Speedy resolution for house owner. P.G. Biddle

4. Efficacy of investigations. Prelim Assess Trial holes Soil Invest. Root Ident. Crack monit. Level Monit. Seasonal or persistent def.   Which vegetation Involved.     Whether remedy effective   Extent and duration of heave   Extent of partial underpinning.    Appropriate level of proof      Speedy resolution for house owner      P.G. Biddle

5. Preliminary assessment Pattern of damage Time of development of damage Probable geology (BGS survey). Proximity and type of vegetation If conclusion probably vegetation …… P.G. Biddle

6. Other factors to consider: Ownership of the tree: Own tree Third party TPO or Conservation Area Value of the tree. P.G. Biddle

7. Value of the tree. LTOA use CAVAT Relevant to remedial options, not to extent of investigations If the owner values the tree, it is worthy of proper investigation P.G. Biddle

8. Other factors to consider: Ownership of the tree: Own tree Third party TPO or Conservation Area Value of the tree. Number of trees / shrubs P.G. Biddle

9. Essential Desirable Useful but not necessary Waste of resources Scope of investigations Value of tree(s) Owner ship Number of trees Level Monit. Crack Monit. Trial hole Root Ident. Plast. index Desic. autumn Desic. other Preliminary assessment sufficient Single Low Own Tree / shrub Many Single High Many Single Low Third Party tree Many Single High Many Single TPO or Cons. area Many P.G. Biddle

10. Application of level monitoring Only if needed Earlier!!!! P.G. Biddle

11. Application of level monitoring • Install level monitoring at first visit • Level distortion survey if possible • 2nd set of readings (after 6 weeks) : • Initial diagnosis of pattern. • Initial diagnosis of which tree(s) involved. • Put TP on notice. TPO application or CA notification. • 3rd / 4th sets of readings (after 12 / 18 weeks) • Confirm diagnosis. Update TP and Local Authority. • Consider need and location for soil investigations. • Decide on and implement action. • Continue monitoring to confirm efficacy. P.G. Biddle

12. Level monitoring with late notification 9 Confirm diagnosis 8 7 ) Action m 6 m ( 5 t n Claim notification e 4 m Confirmefficacy e 3 v Set up Initial diagnosis o 2 M 1 0 s O N D J F M A M J J A O P.G. Biddle

13. Risk assessment P.G. Biddle

14. Castellain Mansions

15. Castellain Mansions Datum April 1995 Movement Sept 1995 P.G. Biddle

16. Risk assessment • With suitable data, one can identify overall degree of risk • But not which individual tree poses that risk. • So should be trying?? P.G. Biddle