Lecture 5 - Site Appraisal PDF

Preview

Summary

Site Appraisal...

Description

Page 1 of 3

Week 5 - Building Design and Appraisal - Site Appraisal Site appraisal - Context -

Acquisition of development land ! May / may not have buildings on it ! May already own it ! May have planning permission or being acquired speculatively !

- Objective - to identify:! - Site conditions in order to inform design ( eg Clay soils, groundwater etc) ! - Physical constrains - Previous foundations, availability of utility services ! - Contaminated land ! - Legal constraints - EG rights of way !

Why is investigation important ?

- Constraints can : ! - Be insurmountable obstacle to development and/or ! - Require extra time ! - Require design changes to proposed development ! - Increase costs = Reduction in value = loss of profit ! - Caveat empor - unless someone makes an inaccurate statement such as this land is perfect, it means that it is the purchasers responsibility to investigate the land - BUYER MUST BEWARE!

To value site (GDV)

- Residual method ! - Gross Development Value (GDV) = Market value of completed development if sold to willing purchaser!

- Land value = GDV - (development costs + profit) ! - Development costs ! - Cost of land ! - Construction costs! - Professional fees ! - Legal costs ! - Cost of loan ! - Transaction costs!

Need to find out about … Physical extent of site ! - Frontage ! - Width/depth ! - Size of neighbouring buildings (maximum height of development)! - Is the site flat or contoured ! - Gross and net developable areas ! - Type of foundation required EG Stepped or flat ! - Drainage ! Physical constraints ! - Soil type / bearing capacity ! - Groundwater ! - Ability of subsoil to drain ! - Any structures (old foundations, sewers, underground lines) below ground ?!

Page 2 of 3

- Pylons ! - Availability of utility services ! Stage 1 : Desk-top study (the cheap part) ! - Ordnance survey records/digimap ! - STATS search ! - Local knowledge ! - Title deeds ( documents providing evidence of title) ! Services below ground ! - Statutory undertakers (utility services plan) ! - Known as STATS investigation ! Stage 2 : Physical investigations (more expensive) ! - Site and topographical survey ! - Dimensions / area / levels ! - Site investigations ! - By geotechnical engineer and hydrologist ! - Trail pits / boreholes ! - Laboratory analysis ! - Underground infrasture mapping ! - Trees ! - Protected species !

Topographical survey Detailed measurement ! - Boundaries ! - Position of features ! - Levels and contours !

Site investigations Investigations by geotechnical engineer ! - Use of trial holes/boreholes/lab ! - Foundation design - soil type and earring capacity ! - Foundation design - Effects of trees ! - Chemicals in soil - requirements for concrete !

Investigation by hydrologist

- Groundwater (permanent or temporary) ! - Flood risk !

Structures and services below ground - Underground infrastructure mapping (radar) ! - Sewers - location ; built-over agreement ! - Redundant and live services (Required for CDM) ! - Old foundations!

Trees -

TPOs registered with LA ! Development area and cost of work affected by trees ! Tree protected zones must be considered ! Penalties !

Contamination and protected species - Contamination ! - Prior use of site (chemicals / toxins in soil) !

Page 3 of 3

- Hazardous or deleterious materials used ins building (HAC/ Asbestos) ! - Presence of controlled plants (Japanese knotweed) !

- Protected species ! - Bats ! - Newts ! - Rare plants !

Legals -

Objective is sufficiently clear (clean) title ! Title : ownership; rights; burdens (of land) ! 65% of land (most urban land) in UK is registered - title proved from land registry documents ! 35% of land is unregistered - title proved from deeds !

To consider: ! - Ransom strips - ! - Easements ! - Rights of way ! - Utilities ! - Rights of light ! - Restrictive covenants ! - Not to … ! - Only to …. ! - Positive covenants ! - To do … !

Listed buildings and conservation areas

- Listed buildings ! - Grades 1,2 & 3 ! - Age / architectural character/ history ! - Listed building consent (separate (more difficult) layer of planning) ! - No demolition, alterations ! - Controlled ! - Conservation area ! - Demolition controlled ! - Materials, form controlled !

Access

- Right over land ! - To build, service, maintain when finished ! - Emergency vehicles (minimum width/ height)...