CORDEK VENTILATION VOID FORMERS VENTFORM PANELS

Transcription

1 Cordek Ltd Spring Copse Business Park Slinfold West Sussex RH13 0SZ Tel: Fax: website: APPROVAL INSPECTION TESTING CERTIFICATION TECHNICAL APPROVALS FOR CONSTRUCTION Agrément Certificate 12/4916 Product Sheet 1 PRODUCT SCOPE AND SUMMARY OF CERTIFICATE This Certificate relates to Ventform Panels, a range of profiled, expanded polystyrene panels used as ventilated void formers under suspended reinforced concrete ground floor slab and ground bearing concrete floor slab constructions to facilitate the passive ventilation of hazardous gases (eg landfill gas and radon) emanating from the ground beneath the building. The panels contribute to the thermal performance of the ground floor construction. AGRÉMENT CERTIFICATION INCLUDES: factors relating to compliance with Building Regulations where applicable factors relating to additional non-regulatory information where applicable independently verified technical specification assessment criteria and technical investigations design considerations installation guidance regular surveillance of production formal three-yearly review. CORDEK VENTILATION VOID FORMERS VENTFORM PANELS KEY FACTORS ASSESSED Ventilation capacity when used in conjunction with an appropriate gas resistant membrane and adequate vents to the outside of the building, the panels will facilitate the effective passive ventilation of hazardous gases emanating from the ground beneath the building subject to the ventilation capacity limits given in section 6. Structural performance the panels have adequate strength to resist short-term construction phase load loading and long-term loads transmitted from the floor construction without undue deformation (see section 7). Thermal performance the panels can contribute towards achieving the design U values specified in the national Building Regulation requirements for a building (see section 8). Durability the long-term durability of the panels has been assessed and is adequate for the design life of the building (see section 10). The BBA has awarded this Agrément Certificate to the company named above for the products described herein. These products have been assessed by the BBA as being fit for their intended use provided they are installed, used and maintained as set out in this Certificate. On behalf of the British Board of Agrément Date of First issue: 31 May 2012 Brian Chamberlain Greg Cooper Head of Approvals Engineering Chief Executive The BBA is a UKAS accredited certification body Number 113. The schedule of the current scope of accreditation for product certification is available in pdf format via the UKAS link on the BBA website at Readers are advised to check the validity and latest issue number of this Agrément Certificate by either referring to the BBA website or contacting the BBA direct. British Board of Agrément tel: Bucknalls Lane fax: Garston, Watford mail@bba.star.co.uk Herts WD25 9BA 2012 website: Page 1 of 10

2 Regulations In the opinion of the BBA, Ventform Panels, when used in accordance with the provisions of this Certificate, will meet or contribute to meeting the relevant requirements of the following Building Regulations (the presence of a UK map indicates that the subject is related to the Building Regulations in the region or regions of the UK depicted): The Building Regulations 2010 (England and Wales) Requirement: A1(1) Requirement: C1(2) Requirement: L1(a)(i) Requirement: Regulation 7 Loading Floors incorporating the panels can be designed to sustain and transmit dead and imposed floor loads to the ground. See section 7 of this Certificate. Preparation of site and resistance to contaminants The panels used in conjunction with an appropriate gas-retardant membrane, can contribute to a floor structure satisfying this Requirement. See section 6 of this Certificate. Conservation of fuel and power When used with additional layers of insulation, the panels can contribute to meeting this Requirement. See section 8 of this Certificate. Materials and workmanship The panels are acceptable. See section 10 and the Installation part of this Certificate. The Building (Scotland) Regulations 2004 (as amended) Regulation: 8(1)(2) Fitness and durability of materials and workmanship The panels can contribute to a construction meeting this Regulation. See section 10 and the Installation part of this Certificate. Regulation: 9 Building standards construction Standard: 1.1 Structure Floors incorporating the panels can meet the requirements of this Standard. See section 7 of this Certificate. Standard: 3.1 Site preparation harmful and dangerous substances Standard: 3.2 Site preparation protection from radon gas The panels used in conjunction with an appropriate gas-retardant membrane, can contribute to a floor structure satisfying these Standards with reference to clauses (1)(2) and (1)(2) respectively. See section 6 of this Certificate. Standard: 6.2 Building Envelope When used with additional insulating layers, the panels can contribute to satisfying the requirements of this Standard, with reference to clauses (1)(2) to (1)(2). See section 8 of this Certificate. Standard: 7.1(a)(b) Statement of sustainability The panels can contribute to meeting the relevant Requirements of Regulation 9 Standards 1 to 6 and therefore, will contribute to a construction meeting a bronze level of sustainability as defined in this Standard. (1) Technical Handbook (Domestic). (2) Technical Handbook (Non-Domestic). The Building Regulations (Northern Ireland) 2000 (as amended) Regulation: B2 Fitness of materials and workmanship The panels are acceptable. See section 10 and the Installation part of this Certificate. Regulation: C2(1)(2) Preparation of site and resistance to dangerous and harmful substances The panels used in conjunction with an appropriate gas-retardant membrane can contribute to a floor structure satisfying this Regulation. See section 6 of this Certificate. Regulation: D1 Stability Floors incorporating the panels can be designed to sustain and transmit dead and imposed floor loads to the ground. See section 7 of this Certificate. Regulation: F2(a)(i) Conservation Measures Regulation: F3(2) Target carbon dioxide Emission Rate When used with additional insulating layers, the panels can contribute to satisfying the requirements of this Regulation. See section 8 of this Certificate. Construction (Design and Management) Regulations 2007 Construction (Design and Management) Regulations (Northern Ireland) 2007 Information in this Certificate may assist the client, CDM co-ordinator, designer and contractors to address their obligations under these Regulations. See section: 3 Delivery and site handling (3.3 and 3.6) and the Installation part of this Certificate. Page 2 of 10

3 Additional Information NHBC Standards 2011 NHBC accepts the use of Ventform Panels, when installed and used in accordance with this Certificate, in relation to NHBC Standards, Chapters 4.1 Land quality managing ground conditions, 5.1 Substructure and ground bearing floors and 5.2 Suspended ground floors. Technical Specification 1 Description 1.1 Ventform Panels are supplied as 1200 mm by 1200 mm square panels, comprising a flat expanded polystyrene (EPS) top piece of either mm or 70 mm thickness and integral EPS projections (legs) of varying profile and length beneath (see Figure 1). Figure 1 Ventform panels Ventform and Panels Ventform 150 and 200 Panels / / square legs (dimensions in mm) 120 nominal 120 nominal 2 centres ovular tapered legs (nominal width 120) 1.2 The panels are available in four different overall depths giving different ventilation capacities and with six maximum load capacities (see Table 1). Page 3 of 10

4 Table 1 Panel characteristics Panel Specification Overall depth Maximum of panel (mm) load capacity (kn.m 2 ) Leg height (mm) Equivalent clear Void depth (1) (mm) Ventilation capacity Nominal ventilated cross-sectional area (2) as seen in elevation (mm 2 per m width of floor) Ventform /20 Ventform / Ventform / Ventform /50 Ventform /20 Ventform / Ventform / Ventform /50 Ventform 150/9 Ventform 150/13 Ventform 200/9 Ventform 200/ (1) Equivalent clear void depth after making allowance for the panel top and the panel legs (2) Ventilated cross sectional area available for the through-flow of air. 1.3 Ancillary items used with Ventform panels but outside the scope of this Certificate are: gas-resistant and damp-proof membrane specification with third-party approval or equivalent. Air bricks and/or telescopic underfloor ventilators Cavity trays 2 Manufacture 2.1 The panels are moulded from flame retardant grade EPS in accordance with BS EN : Different EPS grades are used to create the different load bearing capacities. 2.2 To check product quality is consistently maintained to the required specification, the BBA has: agreed with the Certificate holder/manufacturer the quality control procedures and product testing to be undertaken assessed and agreed the quality control operated over batches of incoming materials monitored the production process and verified that it is in accordance with the documented process evaluated the process for management of nonconformities checked that equipment has been properly tested and calibrated undertaken to carry out the above measures on a regular basis as part of a surveillance process to check that standards are maintained and that the product or system remains as Certificated. 3 Delivery and site handling 3.1 The panels are delivered to site stretch-wrapped in polyethylene sheet in packs of 10 to 15 panels. 3.2 Each panel is embossed with the manufacturers name, the product name (Ventform) and the product specification (depth/maximum load capacity). 3.3 The panels must be protected from high winds and prolonged weathering and stored under cover to avoid prolonged exposure to sunlight. 3.4 The panels must be stored flat, on a firm, level and dry base, and be fully supported to ensure the panels do not distort or bow. 3.5 Contact with solvents and organic based materials should be avoided. 3.6 The panels must not be exposed to flame or ignition and careful consideration should also be given to the management of fire risk when in storage. Assessment and Technical Investigations The following is a summary of the assessment and technical investigations carried out on Ventform Panels. Design Considerations 4 General 4.1 Ventform Panels are designed for use as a ventilated void former beneath suspended reinforced concrete floor slabs and ground-bearing concrete floor slabs to facilitate the passive ventilation of hazardous gases (eg landfill gas or radon) emanating from the ground under the building. Page 4 of 10

5 4.2 To provide an effective gas protection system, the panels must be used with a suitable gas-resistant membrane (1) and have adequate ventilation arrangements provided through external walls of the building to allow air to enter and circulate freely through the void created by the panels (see section 6). (1) Membrane third-party Certificated. 4.3 Detailed guidance on the design and detailing of protective measures for buildings constructed on gas contaminated land is given in the national Building Regulations, NHBC Standards, BS 8485 : 2007 and the following BRE Reports: BRE Report 211 (BR 211 : 2007) Radon: Guidance on protective measures for new dwellings BRE Report 212 (BR 212 : 1991) Construction of new buildings on gas-contaminated land BRE Report (BR 376 : 1999) Radon: guidance on protective measures for new dwellings in Scotland BRE Report (BR 413 : 2001) Radon: guidance on protective measures for new dwellings in Northern Ireland BRE Report (BR 414 : 2001) Protective measures for housing on gas-contaminated land. 4.4 The panels are not designed for use in ground subject to clay heave. 5 Practicability of installation The panels are designed to be installed by a competent general builder, or a contractor, experienced with this type of product. 6 Ventilation capacity 6.1 Where subfloor ventilation is to be provided as part of the gas protection measures, the engineer responsible for the design of the building should determine the required ventilation capacity in accordance with design documents referenced in section 4.3, taking account of: the recorded concentration of the soil gas the known or likely volumetric emission rates of gas the area and shape of the slab the location of the building, the prevailing wind direction and topography of the surrounding ground. 6.2 The appropriate panel specification should then be selected with a ventilation capacity at least equal to that calculated. Equivalent clear void depth and ventilated cross-sectional area per metre width of panel are given in Table 1 for each panel specification. 6.3 The design must incorporate adequate provision in the form of air bricks, telescopic vents and other means to allow air to enter into and circulate freely within the void created by the panels. The type and location of the vents should be determined by the engineer responsible for the design of the buiding and should be shown on the construction drawings. Minimum vent opening sizes are given in the design guidance documents referenced in section Structural performance 7.1 For suspended, reinforced concrete floor slabs, the appropriate panel specification is selected according to the proposed finished thickness of the concrete slab. To limit the maximum anticipated compressive creep deformation of the panel to an acceptable level of 2 mm or less, the maximum uniformly distributed load (UDL) carried by the panel during the initial period (1 to 16 hours) from commencement of the concrete pour, must not exceed the maximum load capacity of the panel (see Table 1). The design UDL load should include the weight of the wet concrete and an allowance for heaping of the concrete during pouring. The minimum allowance for heaping should be taken as 1.5 kn m 2, but may need to be increased depending on the methods used for placing and compacting the concrete. 7.2 For ground-bearing floor slabs, the panel specification should be selected so that it also limits the anticipated maximum long-term (50 year) compressive creep deformation to the level determined by the structural design engineer responsible for the design of the building. This will depend on the type of building and its intended use. 7.3 Anticipated 50 year compressive creep deformations and permissible design loads for each panel specification are given in Table 2. In all cases, the design load should be taken as the maximum combination of unfactored dead and imposed load likely to be transmitted to the panel, determined in accordance with BS EN 1990 : 2002, BS EN : 2002 and National Annexes. Table 2 Long-term creep deformation ground bearing long term creep compression Panel depth (mm) Panel specification Maximum load carrying capacity of the panel (kn m 2 ) Maximum anticipated 50 year compressive creep deformation under a design load equal to maximum load bearing capacity of the panel (%) Maximum permissible design load to limit 50 year creep deformation to 2% (kn m 2 ) and and and and 150 and and Page 5 of 10

6 7.4 For both suspended and ground bearing floor slabs, the structural engineer responsible for the design of the building should confirm the adequacy of the bearing substrate to carry maximum short- and long-term design loads transmitted through the panels. 7.5 Provision should also be incorporated in to the design to limit short-term concentrated loads that could cause localised damage to the panels and gas resistant membrane (for example, under reinforcement spacers). Reinforcement spacers should selected with large base areas and should be located at sufficiently close centres to ensure that the maximum load beneath the spacer does not exceed the maximum load carrying capacity of the panel (see Tables 1 and 2). Where necessary, load-spreader plates should be specified beneath the reinforcement spacers. 8 Thermal performance 8.1 Depending on the panel specification selected, a typical floor construction comprising a 150 mm concrete slab constructed above a Ventform Panel and having a p/a ratio between 0.4 and 0.9, will achieve a calculated U value between 0.27 W m 2 K 1 to 0. W m 2 K 1. Designers should allow for additional insulation as required to meet the typical design U values quoted in the documents supporting the national Building Regulations. 8.2 Calculation of specific design floor U values should be completed in accordance with BS EN ISO : 2007, BS EN ISO 6946 : 2007 and BR443 Conventions for U value calculations (2006 Edition). All floor constructions incorporating Ventform panels should be treated as suspended. The thermal conductivity values given in Table 3 should be used for the Ventform panels. The panels may be simplified as plane boards with the effective thicknesses given in Table 3. Alternatively, detailed thermal modelling may be carried out in accordance with BS EN ISO : Table 3 Design values for use in U value calculations Ventform panel specification (Panel depth/grade) /20 and /20 150/9 and 200/9 / and / 150/13 and 200/13 / and / /50 and /50 Thermal conductivity λ 90/90 (W m 1 K 1 ) (1) (1) Panel effective thickness (mm) (1) For the /, /50, / and /50 panels, the thermal conductivity values quoted have been determined from available mean thermal conductivity data with an increment added as no λ 90/90 values were available. 8.3 Care should be taken during detailed design to avoid thermal bridging at junctions. 9 Maintenance 9.1 Once installed, Ventform panels do not require maintenance. 9.2 To ensure effective ventilation of the void space created beneath the floor construction, airbricks and other venting devices installed in the perimeter walls of the building must be inspected at intervals and maintained free of blockage. 10 Durability The product will continue to perform effectively as a void former for the life of the building. It is rot-proof and water-resistant, dimensionally stable under varying conditions of temperature and humidity, and is unaffected by exposure to radon and methane gas. 11 Re-use and recyclability The polystyrene panels can be fully recycled. Installation 12 General 12.1 Installation of Ventform Panels must follow the requirements of this Certificate and the Certificate holder s installation instructions. Adequate supervision must be maintained and, if required, the Certificate holder s specialists, experienced in site practice and installation of the material, will attend the site to provide demonstrations to ensure correct installation Normal precautions for handling EPS materials should be taken to avoid damaging the product during offloading, storage, handling and installation. Any damaged panels must be replaced before pouring the concrete Protection from wind uplift may be required during installation. Page 6 of 10

7 13 Preparation 13.1 All loose material, eg vegetation, must be removed prior to installation Preparation and levelling of the formation must be as specified on the construction drawings prepared by the structural engineer responsible for the design of the building. This may comprise a layer of concrete blinding over a layer of hardcore, or a compactable blinding Ventilators must be installed in accordance with the construction drawings on opposite walls with sufficient air gaps in any intervening walls to ensure no stagnant gas pockets (dead zones) exist, or are created (see Figures 2 and 3). The ventilators must be placed securely and sealed in position and must be leak-tight Where cavity trays are specified, care should be taken to ensure continuity with the gas resistant membrane. Figure 2 Typical suspended floor slab construction additional floor insulation if required vapour control layer concrete floor slab floor finish cavity tray telescopic void vent ventform 150 or 200 ventilation layer blinding layer gas membrane Figure 3 Typical ground bearing floor slab construction floor finish vapour control layer additional floor insulation if required concrete floor slab cavity tray telescopic void vent gas membrane Ventform or ventilation layer blinding layer Page 7 of 10

8 14 Procedure 14.1 The panels should be arranged to minimise the amount of cutting and re-shaping. Panels must be butted tightly together ensuring all gaps are minimal. Any gaps formed must be no greater than the maximum that can be bridged by the gas retardant membrane. Where cutting is unavoidable, this can be easily completed using a fine tooth saw Once the panels have been installed, a compatible damp-proofing and gas-retardant membrane is laid over the panels with all sealing, joints and details carried out strictly in accordance with the membrane manufacturer s instructions Service entries can be accommodated by cutting the panels to ensure a tight fit. Where holes or cuts are made in the gas-retardant membrane, these must be made good using the sealing and jointing compounds and methods (eg tapes and top-hats specified by the membrane manufacturer) The membrane must be checked thoroughly for integrity by a competent person and any damaged repaired prior to concrete placement To provide protection and avoid damage during the construction phase; such as laying reinforcement and during pouring and placing of the concrete floor slabs, a suitable protective layer can be laid over the gas-retardant membrane Reinforcement spacers should be carefully selected and positioned as set out in section Trafficking across panels should be minimised and concrete poured from a low height or concrete pumping equipment used to avoid localised impact or overloading. Technical Investigations The following is a summary of the technical investigations carried out for Ventform Panels. 15 Investigations 15.1 An examination was made of existing data relating to: long/short term creep thermal performance resistance of EPS mechanical properties to methane gas durability Typical U values were derived for the floor system using modelling and calculation in accordance with BS EN ISO : 2007, BS EN ISO : 2007, BS EN ISO 6946 : 2007 and BR443 Conventions for U value calculations (2006 Edition) A site visit was carried out to assess the practicability of installation The manufacturing processes for the production of Ventform Panels was assessed including the methods adopted for quality control, and details obtained of the quality and composition of the materials used. Bibliography BS 8485 : 2007 Code of practice for the characterization and remediation from ground gas in affected developments BS EN 16 :1997 Thermal insulating products for building applications Determination of compressive creep BS EN 1990 ; 2002 Basis of Structural Design BS EN : 2002 Eurocode 1 Actions on structures General actions Densities, self-weight, imposed loads for buildings BS EN ISO : 2007 Thermal bridges in building construction Heat flows and surface temperatures Detailed calculations BS EN : 2008 Thermal insulation products for buildings Factory made products of expanded polystyrene (EPS) Specification BS EN ISO 6946 : 2007 Building components and building elements Thermal resistance and thermal transmittance. Calculation method BS EN ISO : 2007 Thermal performance of buildings. Heat transfer via the ground Calculation methods Page 8 of 10

9 Conditions of Certification 16 Conditions 16.1 This Certificate: relates only to the product/system that is named and described on the front page is issued only to the company, firm, organisation or person named on the front page no other company, firm, organisation or person may hold or claim that this Certificate has been issued to them is valid only within the UK has to be read, considered and used as a whole document it may be misleading and will be incomplete to be selective is copyright of the BBA is subject to English Law Publications, documents, specifications, legislation, regulations, standards and the like referenced in this Certificate are those that were current and/or deemed relevant by the BBA at the date of issue or reissue of this Certificate This Certificate will remain valid for an unlimited period provided that the product/system and its manufacture and/or fabrication, including all related and relevant parts and processes thereof: are maintained at or above the levels which have been assessed and found to be satisfactory by the BBA continue to be checked as and when deemed appropriate by the BBA under arrangements that it will determine are reviewed by the BBA as and when it considers appropriate The BBA has used due skill, care and diligence in preparing this Certificate, but no warranty is provided In issuing this Certificate, the BBA is not responsible and is excluded from any liability to any company, firm, organisation or person, for any matters arising directly or indirectly from: the presence or absence of any patent, intellectual property or similar rights subsisting in the product/system or any other product/system the right of the Certificate holder to manufacture, supply, install, maintain or market the product/system individual installations of the product/system, including their nature, design, methods, performance, workmanship and maintenance any works and constructions in which the product/system is installed, including their nature, design, methods, performance, workmanship and maintenance any loss or damage, including personal injury, howsoever caused by the product/system, including its manufacture, supply, installation, use, maintenance and removal any claims by the manufacturer relating to CE marking Any information relating to the manufacture, supply, installation, use, maintenance and removal of this product/ system which is contained or referred to in this Certificate is the minimum required to be met when the product/system is manufactured, supplied, installed, used, maintained and removed. It does not purport in any way to restate the requirements of the Health and Safety at Work etc. Act 1974, or of any other statutory, common law or other duty which may exist at the date of issue or reissue of this Certificate; nor is conformity with such information to be taken as satisfying the requirements of the 1974 Act or of any statutory, common law or other duty of care. Page 9 of 10

10 British Board of Agrément tel: Bucknalls Lane fax: Garston, Watford Herts WD25 9BA 2012 website: Page 10 of 10