Case Study 1 Code level 3

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Shavonne Powers
7 years ago
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Design Team Contractor - LHL Development Ltd Developer - LHL Development Ltd Architect -

1 Case Study 1 Code level 3 Norbury Court Staffordshire Is a development of seven three bedroom houses, one two bedroom house and one three bedroom bungalow. Design Team Contractor - LHL Development Ltd Developer - LHL Development Ltd Architect - Sammonds Architectural Environmental Design Consultants - Hydrock Consultants Engineers - Sammonds Architectural

Key sustainability features: solar thermal water heating low flow rate sanitary ware rainwater recycling for garden environmentally benign material high levels of insulation recycling bins.

2 Key sustainability features: solar thermal water heating low flow rate sanitary ware rainwater recycling for garden environmentally benign material high levels of insulation recycling bins. passive sole design Technical Performance External fabric - timber frame with phenolic foam insulation U-value of 0.29W/m2K Roof timber frame with cut block foam insulation U-value of 0.20W/m2K Floor Concrete beam with polystyrene infill U-value 0.21W/m2K Doors and windows Double glazed, low e windows with a U value of 1.20W/m2K and doors average U-value of 2.0W/m2K Air permeability 5.63m3/@50pa for the first complete dwelling

Cost and Value: The build cost excluding land costs and fees was 950 per sq metre. This equated to an estimated 7,500 more per unit to meet the requirements of Code Level 3.

3 Cost and Value: The build cost excluding land costs and fees was 950 per sq metre. This equated to an estimated 7,500 more per unit to meet the requirements of Code Level 3. Private sale value of these properties was estimated to be 10% higher than for an existing house in the local area. Lessons learnt: Using a good Code for Sustainable Homes assessor and working with them from the start. Not all renewable energy technologies will be appropriate for all sites Achieving Code Level 3 means extra costs Supply chains for some items required to achieve Code Level 3 and above are sometimes still in development.

Developer Pippin Properties Environmental Design Consultancy Brookes Devlin

4 Case study 2 Code level 5 The Old Apple Store Somerset Private housing, five units of detached and terraced houses Design Team Contractor Ecos Homes Developer Pippin Properties Environmental Design Consultancy Brookes Devlin Architect Malcolm McAll Design Consultant O2i Design Engineers John Beverage/ Ellis & Moore

Sustainability features Photovoltaic cells Solar thermal water heating Passive solar design Wood pellet boiler Low air-permeability Low energy lighting, Triple glazing Metering and plans for future

5 Sustainability features Photovoltaic cells Solar thermal water heating Passive solar design Wood pellet boiler Low air-permeability Low energy lighting, Triple glazing Metering and plans for future post occupancy monitoring. Rainwater harvesting High levels of insulation Technical Performance External Fabric Thermally efficient timber cassette shell U-value 0.14W/m2K Roof Engineered I beams filled with recycled newspaper insulation with 100mm wood fibre with OSB top and bottom with an internal vapour control U-value 0.12W/m2K Floor Concrete planks with 150mm foam insulation under 50mm screed. U- value of 0.15W/m2K Doors and windows - triple glazed FSC certified U-value 1.2W/m2K and 1.1W/m2K Air Permeability Between 2.57 and 2.17m3/h@50pa

6 Cost and Value The build cost, excluding land costs and fees was 1,375 per sq metre. This higher than average build cost was attributed to the prototype nature of the development, the time and labour taken during the learning process and the additional costs for installing renewable energy and low carbon heating systems required for Code Level 5. Sale values of the properties were between 275,000 and 399,000, or 2,238-2,615 per sq metre. Sales prices in the local area for existing stock was about 2,045 per sq metre. Lessons Learnt Designing for Code Level 5 required detail knowledge and careful consideration of CSH criteria at the earliest design stage. Planning from the outset was crucial to achieving Code Level 5 objectives. An educated and dedicated construction team is essential to meeting the challenges of higher level Code development.

7 Case study 3 Code level 5 Mid Street - Surrey 2 Two bedroom flats located in South Nutfield. The first publicly funded Social housing development in the UK to achieve Code Level 5. Design Team Contractor Osborne Developer Raven Housing Trust Architect Harrington Design Engineers BEP Consulting Engineers Ltd

Sustainable Features Passive solar design Rainwater harvesting Environmentally friendly materials High levels of insulation low levels of air-permeability Low energy lighting Triple gazed windows

8 Sustainable Features Passive solar design Rainwater harvesting Environmentally friendly materials High levels of insulation low levels of air-permeability Low energy lighting Triple gazed windows MVHR Biomass pellet boiler Energy rated white goods Technical Performance External Fabric Insulated panel system with 50mm external insulation value0.14w/m2k Roof Timber roof concrete tiles with 400mm mineral wood insulation U-value 0.13W/m2K Floor 75mm insulation U-value 0.14W/m2K Doors and windows U value 0.80W/m2K. Doors U-value of 1.2W/m2K Air Permeability 4.9m3/h@50pa

9 Cost and Value Build cost excluding land costs and fees was c. 1,850 per sq metre. This was estimated to be an uplift of 20% over standard build costs. The biomass boiler presented the biggest source of problems requiring servicing every1-2 weeks. Significantly adding to maintenance costs. The sales value of the homes was estimated to be c. 2,857per sq metre, equal to or above sale values for equivalent properties in the area. Lessons learnt It was important to involve an experienced code assessor before drafting initial designs. Construction details need to be produced early in the design process. Shared heating systems can be a practical and cost effective solution. MVHR can significantly reduce energy requirements if correctly specified and installed. A good relationship and understanding with the site manager is necessary for a design to be realised. Material for text and photographs copyright of Crown The Code for Sustainable Homes (case studies)

Case Study 4 Code Level 3 Jarvie Close, Hunstanton A development of 10 1-4 bedroom houses and flats built for Hastoe Housing Association Design

10 Case Study 4 Code Level 3 Jarvie Close, Hunstanton A development of bedroom houses and flats built for Hastoe Housing Association Design Team Contractor E.N Suiters Ltd Architect Parsons and Whittley Ltd Code Assessor Parsons and Whittley Ltd Engineer Scott Wilson Consultant Engineers

Sustainable Features Ground source heat pumps Low energy light fittings Rainwater butts for garden Super insulation Passive solar design Low flow rated sanitary ware Recycling Technical Performance

11 Sustainable Features Ground source heat pumps Low energy light fittings Rainwater butts for garden Super insulation Passive solar design Low flow rated sanitary ware Recycling Technical Performance External Fabric- Cavity wall construction with facing brickwork, U- value 0.26W/m2k or 0.22W/m2k In areas finished with flint. Roof mineral wool insulation laid between and over ceiling joists U- value 0.13W/m2k Floor proprietary concrete beam & block with insulation & screed above -U-value 0.15W/m2K Doors & Windows Double glazed, lowemissivity windows U-value 1.8W/m2K and doors U-value of 1.20 W/m2K Air Permeability

Cost and Value Due to this scheme being classed as a Rural Exception Site there were specific design requirements that brought about additional costs.

12 Cost and Value Due to this scheme being classed as a Rural Exception Site there were specific design requirements that brought about additional costs. To achieve Code for Sustainable Homes Level 3 Ground Source Heat Pumps & Velfac glazed screens & windows for passive solar gain contributed 106,115 to the overall cost. The total cost per sq metre excluding land and landowner s contribution to services was 1, Lessons leant Early consideration of Code issues enabled the design to be delivered that accommodated all of the Code requirements with relative ease. An experienced contractor with a good understanding and previous experience of Code requirements further enabled easy delivery of a level 3 scheme. Using a Code Assessor and working with them from the start helped to iron out problems during construction.

The development was planned to Code Level 4 even before it was mandatory for housing associations to

13 Case Study 5 Code Level 4 Holt Road & Swans Close Norfolk A mixed development of 7, 2-3 bedroom houses and flats developed for Hastoe Housing Association. The development was planned to Code Level 4 even before it was mandatory for housing associations to achieve this. Design Team Contractor - E.N.Suiters Ltd Architect Parsons & Whittley Ltd Code Assessors - Parsons & Whittley Ltd Engineer Scott Wilson Consultant Engineers

Sustainable Features Ground source heat pump Passive solar design Low flow sanitary ware Rainwater recycling for garden Low energy lighting Internal recycling bins Positive enhancement of the site

14 Sustainable Features Ground source heat pump Passive solar design Low flow sanitary ware Rainwater recycling for garden Low energy lighting Internal recycling bins Positive enhancement of the site ecology Technical Performance External Fabric Timber Frame with Facing Brickwork. Cavity fully insulated U-value 0.25W/m2K Roof Timber Frame with mineral wool insulation laid between & over ceiling joists U-value 0.11W/m2K Floor Proprietary Concrete Beam & Block with insulation & screed above. U value 0.16W/m2K Doors & Windows Double glazed, lowemissivity windows U-value of 1.8W/m2K and doors with a U-value of 1.20 W/m2K Air Permeability at 5.16m3/@50pa

Cost and Value Additional costs were incurred in three specific areas: Landowner & Local Authority design requirements Features to achieve Code for Sustainable Homes Level 4 (absence of gas) Specific

15 Cost and Value Additional costs were incurred in three specific areas: Landowner & Local Authority design requirements Features to achieve Code for Sustainable Homes Level 4 (absence of gas) Specific rural scheme requirements The total cost per sq metre excluding land and landowner s contribution to services was 1, Lessons Learnt As the first Code scheme for the design team, and the main contractor, some steep learning curves had to be accommodated. Ensuring sub- contractors understood the requirements for Code Level 4 proved difficult especially when most were set in their ways. Significant problems were encountered in obtaining responsibly sourced materials due to lack of interest from the supply chain to make it a high priority. Surface water disposal proposals had to be continually re-examined to achieve compliance.

Case Studies of Successful Code for Sustainable Homes Projects

Case Studies of Successful Code for Sustainable Homes Projects Sustainable Homes publish the Sustainable Homes Index For Tomorrow (SHIFT) and are a leading trainers of Code for Sustainable Homes assessors.