Insulated Ground Floors NEW & IMPROVED DESIGN

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1 Hanson Building Products Insulated Ground Floors NEW & IMPROVED DESIGN

2 8 Insulated Ground Floors Jetfloor from Hanson has been the market leading solution for thermally insulated structural ground floors since its introduction in And now it s even better. Jetfloor components 1. mm or 225mm prestressed beam 2. Thermalite spacer block 3. Eps infill block 4. Psi-Block 5. Damp-proof course mm Thermalite coursing block for screed rail 7. 80mm eps overlay sheet 8. 70mm concrete topping 9. Membrane if required Jetfloor was the UK s first system to use expanded polystyrene blocks combined with a structural concrete topping to provide high levels of thermal insulation. Over decades it has been successfully used in tens of thousands of new homes. Today our latest development of Jetfloor presents the platform for a range of U values and enhanced Psi values providing a future-proofed robust solution for housebuilders, specifiers and homeowners. System Overview Our new Jetfloor consists of standard mm and 225mm prestressed concrete beams positioned at varying centres dependent on load conditions. The beams are infilled with expanded polystyrene (eps) blocks which are supplied in lightweight easy to handle lengths enabling rapid coverage of large areas of floor. The eps blocks are available in a range of configurations providing a flexible approach to achieving U values. The unique Thermalite Psi- Block reduces thermal linear bridging and improves the Psi value at floor and wall junctions helping reduce the overall dwelling emission rate (DER). The floor is completed with a structural concrete topping reinforced with polypropylene fibres laid over a minimum of 80mm eps sheet insulation. Hanson Concrete specification: 70mm concrete strength class RC25/30 Reinforced with polypropylene fibres or steel mesh reinforcement Jetfloor Benefits Thermal Flexible U value performance Improved Psi value due to unique Psi- Block Thermal mass Cost of construction Reduced excavation and spoil removal No waste Increased speed of build No specialist skills required Sustainability A+ Green Guide rating Reduced dwelling emission rates Accredited to BS EN and BES 6001 responsible sourcing Quality Manufactured in a quality controlled environment in accordance with BS EN ISO 9001:2000 CE marked and certified by the BBA to latest relevant codes and standards Service Available nationwide Supply only or supply and install Comprehensive in-house technical support 2 Hanson Jetfloor Hanson Jetfloor 3

3 Thermal Performance U values W/m² K The measure of heat-loss through the fabric of a building is expressed as a U value with limiting values set out in the building regulations. However, to fully comply with the building regulations, the overall dwelling emission rate (DER) must be lower than the target emission rate (TER) when calculated in SAP. To achieve this, lower U values may be required. The new improved Jetfloor provides a range of U value options that will help improve the overall DER. The following table demonstrates this range based on specific Perimeter/ Area Ratios and insulation material lambda values (λ). P/A U value W/m² K λ λ Note: U values are based on NJB1 beam centres. Actual house-type values will vary dependent on floor layout. λ values (W/m K) and Y values (W/m² K) Heat is also lost through thermal bridges or junctions in a building and is expressed as a Y value. Its units of measure are the same as the U value W/m² K. To calculate the Y value the length of the thermal bridge must be multiplied by the Psi value of the junction of the building being considered i.e. the wall to floor junction. The Psi value is the measure of the thermal transmittance at the thermal bridge and is calculated using thermal modelling, its units of measure are W/m K. The new Jetfloor incorporating the new Psi-Block has resulted in significantly improved Psi values as shown on the following table: Floor Detail Psi value (W/m² K) New Jetfloor 0.03 to 0.10 (1) Accredited construction details SAP conventions document default 0.16 (2) 0.32 (2) (1) Values based on wall U-value of 0.28 W/m 2 K and floor U-value of 0.15 W/m 2 K. (2) From SAP table K1. 4 Hanson Jetfloor Hanson Jetfloor 5

4 Structural Performance Load-span tables Prestressed beams Beam details 77 Beam erence Width (mm) Height (mm) Weight (kn/m) Weight (kg/m) BT RD T Section Details Detail 5 Detail 1 The load-span tables below are given as a guide only. Further advice is available on request. Load-span tables Detail 4 NJB NJB3 0.8 NJR NJR NJR NJT NJT Hanson Jetfloor NJT Imposed load Imposed load Imposed load Imposed load Imposed load Imposed load Imposed load Imposed load mm Beam 4.45 mm Beam Typical layout Less than 300mm LESS THAN 300MM mm Beam mm Beam 0.56 mm Beam NJB1 Detail 2 225mm Beam 225mm Beam Imposed load 225mm Beam mm Beam (Based on floor finishes of 70mm thick concrete topping having minimum strength class RC25/30 reinforced with either polypropylene fibres or steel reinforcement mesh on sheet material of minimum compressive strength N/mm2) Detail 6 Detail 3 Detail 7 Hanson Jetfloor 7

5 Installation Guide This installation guide provides step-by-step instructions required to install the new Jetfloor system. The installation team shall refer to the beam setting out drawing which has been approved and issued prior to delivery. Step-by-step instructions Lay DPC on top of the bearing wall. This wall must be constructed in advance of the floor being installed to allow the mortar to reach its design strength. 2 Using suitable plant equipment place the prestressed concrete beams at the approximate locations and centres as shown on the approved drawing. 3 Place the perimeter Psi-Block at either end of the plot, ensuring blocks are bedded on mortar. 4 Psi-Blocks can be cut to suit using a proprietary hand saw. 5 Working from one end of the plot use the spacer blocks to accurately set out the position of the beams which will have been arranged to suit the location of service risers. Ensure that the beams are placed tight against the spacer blocks. 6 Once the beams have been positioned the polystyrene infill blocks can be inserted. The blocks can be cut with a hand saw and off cuts from the end of a run can be reused within the floor. Any holes required for service pipes can be cut out of the blocks. 7 Bed the Thermalite coursing blocks around the perimeter. This will provide a screed rail to facilitate the correct depth of concrete to be poured to achieve the correct floor construction depth. 8 Once the mortar has cured sufficiently and multiple beams have been concreted together, the 80mm thick insulation sheets can be laid over the top of the floor and cut with a hand saw to suit the layout. Any offcuts can be reused within the floor. Any gas membrane that may be required should be positioned above the beams and below the sheet material. 9 If required install the perimeter edge insulation strips against the perimeter wall. 10 Install any gas carcassing or underfloor heating pipes that may be required. This can be secured to the top insulation sheet material using standard pipe clips. 11 Pour the fibre reinforced concrete topping ensuring that the concrete is not poured from a height greater than 500mm and that heaping is kept to a height not greater than 300mm. 12 The concrete topping can be tamped and floated as required. Please consult with your concrete supplier for the correct installation method. Tips and hints Once the beams have been accurately set out, the perimeter Psi-Blocks and spacers blocks can be bedded on mortar and the coursing blocks can be bedded. This will allow the polystyrene insulation and concrete topping to be installed in one day. 3. Scaffolding boards can be used to hold down the insulation sheet should strong winds prevail prior to placing the concrete topping. 4. Small offcuts of the insulation can be used to effectively seal gaps around any service openings. 6. If required, any DPM or gas membrane should be installed between the top layer of insulation and the infill blocks. This will ensure that any fixings required for pipework etc. will not compromise the membrane. 2. Large service openings are best accommodated by placing a full block either side of the opening and taking out half the opening from each block. 5. Underfloor heating pipes can be accommodated. The standard pipe clips can be secured to the top insulation sheet material Hanson Jetfloor 9

6 Jetfloor a cost-effective solution Suspended in situ concrete beam and building block 175 beam and building block Their findings clearly show that, based on similar U value performance, new Jetfloor is the most cost-effective solution. One of the key areas that helped make the difference was the overall floor thickness particularly when compared to a 175mm deep beam and block solution. The reduced floor thickness with Jetfloor will inevitably lead to cost savings through the reduction of dig and spoil removal costs. When you add the inherent speed of installation and the robust edge details it is easy to see how new Jetfloor will give housebuilders and specifiers cost-effective certainty of compliance with the latest requirements of part L of the building regulations. Turner & Townsend testimonial: We have extensive experience of housing schemes and helping to deliver value for our clients. We have applied our knowledge to review the new Jetfloor product. Certainly given typical build requirements and site conditions the Jetfloor system provides a good cost-effective solution with the benefit of reduced off site disposal. It would gnidliub ybthat deriuqwe er erehw certainly be an option noitalusni dnuos rof snoitaluger would advise our clients to sehsinif consider on housing projects. Hollowcore Retaining Walls Structural solution for apartments and commercial buildings. Engineered solution for retaining structures and materials storage. Beam and Block Box Culverts Ideal solution for first floors in houses. Wide range of applications including watercourse management and water attenuation. Stairs and Landings Omnia Bridge Deck Standard and bespoke stairs for a wide range of applications. Permanent formwork for bridge structures. tew suounitnoc redliub yb ratrom rebmac pu ekat ot Comparison diagram Finished floor level 300 Finished floor level Increased dig and spoil removal costs Beam and Block Hanson also produces a wide range of related solutions including Hollowcore, stairs and landings and conventional beam and block. This is complemented by a wider range of design solutions that includes Retaining Walls, Box Culverts and Omnia Bridge Deck. 450 During the development of our new Jetfloor we engaged the services of cost consultants Turner & Townsend who made detailed cost comparisons between a range of structural ground floor solutions including: Design Solutions For more information on the Jetfloor system Tel: jetfloor@hanson.com Or go to: hansonjetfloor.co.uk to watch our installation video 10 Hanson Jetfloor Hanson Jetfloor 11

7 Hanson Cement Our companies and products Hanson UK is the leading supplier of heavy building materials to the UK construction industry. We are split into three business lines Hanson Cement, Hanson Building Products and Hanson Quarry Products. Hanson UK is owned by the HeidelbergCement Group, which employs over 53,000 people and operates worldwide. Hanson UK employs around 4,200 people across over 300 sites. For detailed information on all areas of Hanson and our products visit: hanson.com/uk Hanson UK products and services Concrete Ready-mixed concrete Ready-mixed mortar Dry silo mortar Screed EcoPlus Bulk cement products Grey White Blends Regen (GGBS) Aggregates Sand Gravel Crushed rock Recycled aggregates Packed products Cement Ready to use concrete, mortars, asphalt, aggregate and sand Asphalt Hot rolled asphalt Stone mastic asphalt Asphalt macadams Contracting Highway maintenance Road surfacing Civil engineering Wind farm construction Waste to energy facilities MOD works Bricks Clay bricks and brick specials Clay pavers Bespoke clay products Blocks Aircrete Aggregate Precast concrete Retaining walls Culverts Barriers Floors Stairs Structural walls Basements Off-site solutions Cladding and render systems Cladding and render systems External Wall Insulation (EWI) Structural EWI Fastbrick Other products and services SUDS Geothermal Roofing Chimneys Brick and block laying contractors Hanson Precast Products Hanson House, 14 Castle Hill, Maidenhead, Berkshire SL6 4JJ hansonjetfloor.co.uk 09/2013/2623MICH