Cressingham Gardens Tulse Hill, London Residential Conversion
Total Page：16
File Type：pdf, Size：1020Kb
Cressingham Gardens Tulse Hill, London Residential Conversion Feasibility Report - Draft February 2016 For the London Borough of Lambeth Produced by Tibbalds with GSA Confidential Tibbalds Planning and Urban Design 19 Maltings Place 169 Tower Bridge Road London SE1 3JB Telephone 020 7089 2121 [email protected] www.tibbalds.co.uk Cressingham Gardens ❚ Contents 1.0 Introduction 2.0 Description of the Existing Buildings 3.0 Residential Quality 4.0 General Considerations 5.0 Block Specific Considerations 6.0 Typical Block Study 7.0 Strategic Sitewide Considerations 8.0 Example Projects 9.0 Summary ©TIBBALDS MONTH 2016 Cressingham Gardens Residential Conversion Feasibility 1 ❚ 1.0 Introduction The estate was designed in 1969, since that time some aspects of the housing estate have worked well, but there have also been issues. As a result London Borough of Lambeth are currently considering the future of the estate, and ways in which the area can be regenerated. There is some opposition from the local residents’ group to regeneration options that would involve demolition of the existing housing stock. Despite some negative issues (such as break-ins to the basement parking, problems with drainage and foul water leakages in the garages – to name a few), the estate appears to be popular. It is well kept and appeared to be relatively safe (despite its less than conventional layout). The residents have put together an alternative Peoples Plan for the future of the estate that does not involve demolition – involving the conversion of basement / undercroft parking to residential use. This report is preliminary investigation of the design issues that would be raised by such a conversion programme. This report focuses on testing ideas for the residential Schematic drawing showing Hardel Walk conversion of four garage areas within the estate as shown (diagram from ‘Tulse Hill’ document by opposite. London Borough of Lambeth - Jan 1969) Existing Section (showing Hardel Walk) Cressingham Gardens Residential Conversion Feasibility ©TIBBALDS FEBRUARY2016 2 ❚ 1.0 Introduction Location Plan showing the four blocks with basement car parking ©TIBBALDS MONTH 2016 Cressingham Gardens Residential Conversion Feasibility 3 ❚ 2.0 Description of the Existing Buildings This study looks at four apartment buildings: ■■ Hardel Walk; ■■ The adjacent block we are referring to in this report as Hardel Walk South; ■■ Longford Walk; ■■ Crosby Walk. The building form is broadly similar for all four blocks, however there are site specific issues relating to each block which will be described later in this report. Each block has a communal undercroft or semi-basement car park. The structure visible within the basement is a concrete Crosby Walk frame. The downstand beams are of varying depths, with a deeper beam occurring every two bays. Within each basement the general arrangement includes garages along the southern edge (western edge of Hardell Walk) and open parking areas along the northern side (or east for Hardell Walk) with railings onto the adjacent road, path or external space. Each of the basement areas gets light from one side only. Access to the basement parking areas is generally from either end via electric gates. Often this access is ramped. Each of the garage areas is set back behind an overhang of the residential accommodation above. Longford Walk Hardel Walk Hardel Walk South Cressingham Gardens Residential Conversion Feasibility ©TIBBALDS FEBRUARY2016 4 ❚ 3.0 Residential Quality The London Residential Design guide has been developed London Design Guide 5.4.1 requirement for 2.5m min to ensure that all new housing in London is of a good quality. floor to ceiling height in habitable rooms (ideally higher The guidance promotes residential accommodation that in ground floor homes). is robust and appropriate for use by people throughout The current floor to ceiling height is generally low (it varies, their whole lifetime (Lifetime Homes). It also should be but on average it is about 2.3m to underside of the concrete sustainable and allow people to lead a good quality of life. slab). The existing buildings all have a concrete structure The Peoples Plan suggests that the proposed dwellings with downstand beams of various depths which are even would be affordable tenures. It is worth noting that in lower (in some instances only about 1.8m clear beneath the addition to the London Residential Design Guide, affordable beams). homes will be expected to comply to further design ■■ Lowering the ground floor slab would require a structural and performance criteria (often associated with funding review (for impact on foundations). This might require arrangements), such as Housing Quality Indicators (HQI). expensive underpinning. These criteria are in place to ensure that the design of homes take into account how people want to use their home and ■■ Consider how services (including existing services their surroundings, now and in the future. to / from existing flats above) and ventilation is accommodated within the ceiling zone. This will impact Any new proposed housing within the London Borough of on the floor to ceiling height Lambeth would be expected to comply with the guidance within the London Residential Design Guide. The prospect ■■ Possible requirement for insulation at ceiling level. of converting basement car parking to residential at ■■ Possibly request a dispensation regarding floor to ceiling Cressingham Gardens raises the following issues regarding height, particularly where downstand beams would occur the quality of the resulting residential accommodation. The within the new flats. items listed below are not exhaustive, but represent the key issues that might have implications for cost planning and the delivery of the proposal. Longford Walk - showing the low floor to ceiling heights Design proposals suggest lowering the ground floor slab ©TIBBALDS MONTH 2016 Cressingham Gardens Residential Conversion Feasibility 5 ❚ 3.0 Residential Quality London Design Guide 5.5.1 Daylighting London Design Guide 3.1.3 Level access into the home. Getting adequate daylighting into ground floor flats would This would require the external landscape scheme to provide be challenging, particularly getting adequate light levels a very gently sloping or flat pathway to the new front doors. into kitchens and living rooms. The following considerations There are a couple of options for accessing the front doors of could help: the proposed dwellings - either from a communal corridor at ■■ Design facades with generous amount of glazing. the rear of the flats, or giving each dwelling its own front door directly from the public realm. ■■ Locate the façade to align with the building face above (not set back from it) The greatest challenge to achieving this would be at Hardel Walk where the existing ground level noticeably slopes in a ■■ Don’t make the habitable rooms too deep. north – south direction. The floor slab of the car park is also ■■ Place bathrooms and storage at the backs of the flats / sloping here. maximise habitbale accommodation next to the facade, ■■ Consideration must be giving for achieving access for the where there is more light. disabled. Existing Section- undercroft does not recieve much daylight Hardel Walk - the change in level between garage floor and outside Cressingham Gardens Residential Conversion Feasibility ©TIBBALDS FEBRUARY2016 6 ❚ 3.0 Residential Quality London Design Guide 4.10 - Requirement for all homes London Design Guide 5.2.1 requirement to avoid north to have private amenity space. facing single aspect dwellings. The minimum width of private amenity provision is 1.5m. 3 of the 4 blocks (Longford Walk, Crosby Walk & Hardel This could be achieved by the provision of private patio Walk South) would have predominantly north facing aspect space or small gardens outside the existing buildings. (resulting in primarily north facing single aspect dwellings). This would require localized external works schemes – of ■■ Consider use of bay windows. The design of which could varying degrees of complexity – according to particular site fit beneath the existing projecting oriel windows above. conditions. ■■ Or even a projecting extension with roof glazing (like a The Hardel Walk block would present the greatest conservatory). challenges, because of the considerable change in level between the car park floor and the external access. This could result in the loss of further existing parking spaces. Localised landscape works would be required. This would result in a net loss of communal open space (communal open space being converted to private amenity space). However a mitigating factor could be the proximity of high quality public open space in Brockwell Park. Crib wall precedent Projecting extension with roof glazing precedent ©TIBBALDS MONTH 2016 Cressingham Gardens Residential Conversion Feasibility 7 ❚ 4.0 General Considerations There are other general issues that are common to all blocks. ■■ The car park areas are deep plan and generally single aspect. The rear space would not receive adequate daylighting for residential use. Perhaps these areas could be used for lock-up storage, bike stores or refuse stores (if effective ventilation can be achieved). ■■ An option could be looked at to retain the rear part of the basement as parking (requiring at least 11m for a 5m space and 6m reversing zone), with just the front part converted to residential (approximately 5m deep). Hardel Walk - existing gas pipe ■■ Drainage from upper floors come down into the basement. Some pipes appear to be rainwater, others appear to be foul water. Where the pipes enter the basement form above, it is likely that a rodding point (for access to the pipework) would be needed. This should ideally be located outside the demise of the dwelling. ■■ Other services are routed through the basements (there is a noticeable gas pipe in the Hardel Walk basement). This would require the gas supply to the flats above to be re-routed. ■■ There are noticeable manholes in the floor surface of some areas of the car parks. This suggests that services run beneath the floor slab.