Owens-Corning Building Products (UK) Ltd P O Box 10 St Helens Merseyside WA10 3NS Tel: Fax:

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1 Owens-Corning Building Products (UK) Ltd P O Box 10 St Helens Merseyside WA10 3NS Tel: Fax: CI/SfB (21.9) Rm1 (M2) Agrément Certificate No 95/3212 Designated by Government to issue European Technical Approvals Product THIS CERTIFICATE REPLACES CERTIFICATES Nos 94/2989 AND 86/1790 AND RELATES TO CROWN DRITHERM, A RESIN BONDED GLASS WOOL CAVITY WALL INSULATING MATERIAL IN SLAB FORM. The product is for use both in buildings up to 12 metres in height and in buildings over 12 metres and up to 25 metres in height, subject to the conditions contained in the Design Data part of this Certificate. Crown Dritherm is installed during construction and is for use as a full fill and partial fill slab to reduce the thermal transmittance of cavity walls with masonry inner and outer leaves. It is essential that the walls are built in accordance with the conditions set out in the Design Data and Installation parts of this Certificate. CROWN DRITHERM Isolation de murs à double paroi Kerndämmung Building Regulations 1 The Building Regulations 1991 (as amended 1994) (England and Wales) The Secretary of State has agreed with the British Board of Agrément the aspects of performance to be used by the BBA in assessing the compliance of cavity wall insulation with the Building Regulations. In the opinion of the BBA, Crown Dritherm, if used in accordance with the provisions of this Certificate, will meet or contribute to meeting the relevant requirements. Requirement: B3(4) Internal fire spread (structure) The product is non-combustible to BS 476 : Part 4 : 1970(1984) and therefore meets this Requirement in buildings of every purpose group. When the product is used as a full fill slab it may be regarded as a cavity barrier where an insulated wall connects to the cavity of an uninsulated wall. See sections 7.1 to 7.3 of this Certificate. Requirement: C4 Resistance to weather and ground moisture Tests for water resistance carried out by the BBA indicate that a wall filled with the product meets this Requirement provided the completed wall complied with the conditions set out in sections 6.2, 6.5 to 6.7, 6.9 and 6.10 of this Certificate. The product does not absorb water by capillary action and may therefore be used in situations where is bridges the dpc s of the inner and outer leaf. See sections 8.3 and 8.4 of this Certificate. Requirement: L1 Conservation of fuel and power Data obtained by the BBA indicate that when the product is used in accordance with this Certificate the walls constructed meet or contribute to meeting the U value requirements. See sections 10.2 to 10.4 of this Certificate. Requirement: Regulation 7 Materials and workmanship The product is acceptable. See sections 11.1 and 11.2 of this Certificate. 2 The Building Standards (Scotland) Regulations 1990 (as amended) In the opinion of the BBA, Crown Dritherm, if used in accordance with the provisions of this Certificate, will satisfy or contribute to satisfying the various Regulations and Technical Standards as listed below. Regulation: 10 Fitness of materials Standard: B2.1 Selection and use of materials and components The product is acceptable. Regulation: 12 Structural fire precautions Standard: D2.3 Non-combustibility The product is non-combustible to BS 476 : Part 4 : 1970(1984) and may be used in buildings of any purpose group. See sections 7.1, 7.2 and 7.4 of this Certificate. Standards: D Cavity barriers No cavity barriers are required provided all of the cavity is filled. See section 7.4 of this Certificate. continued Readers are advised to check the validity of this Certificate by either referring to the Index of Current BBA Publications or contacting the BBA direct (Telephone Hotline ).

2 continued Regulation: 17 Preparation of sites and resistance to moisture Standard: G2.6 Resistance to moisture from the ground The product does not absorb water by capillary action and may therefore be used in situations where it bridges the dpc s of the inner and outer leaf. See section 8.5 of this Certificate. Standard: G3.1 Resistance to precipitation Tests by the BBA indicate that a wall filled with the product will satisfy this Regulation provided it complies with the conditions set out in sections 6.2, 6.5 to 6.7, 6.9 and 6.10 of this Certificate. See also section 8.6 of this Certificate. Regulation: 22 Conservation of fuel and power Standard: J2.2 Performance standards Data obtained by the BBA indicate that when the slabs are used in accordance with this Certificate they will meet or contribute to satisfying this Standard. See sections 10.2 and 10.3 of this Certificate. 3 The Building Regulations (Northern Ireland) 1994 (as amended 1995) In the opinion of the BBA, Crown Dritherm, if used in accordance with the provisions of this Certificate, will satisfy or contribute to satisfying the various Building Regulations as listed below. Regulation: B2 Fitness of materials and workmanship The product is acceptable. See sections 11.1 and 11.2 of this Certificate. Regulation: C5 Resistance to ground moisture and weather Data obtained by the BBA indicate that a wall incorporating the product can satisfy this Regulation provided it complies with sections 6.2 and 6.5 to 6.7 of this Certificate. See also sections 8.5 and 8.6 of this Certificate. The product does not absorb water by capillary action and may therefore be used where it bridges the dpc of the inner and outer leaf. See section 8.6 of this Certificate. Regulation: E6 Internal fire spread Structure The product is non-combustible to BS 476 : Part 4 : 1970(1984) and may be used in buildings of any purpose group. See sections 7.1, 7.2 and 7.4 of this Certificate. No cavity barriers are required provided all of the cavity is filled. See section 7.4 of this Certificate. Regulation: F2 Conservation of fuel and power Data obtained by the BBA indicate that when the product is used in accordance with this Certificate the walls constructed will meet or contribute to meeting the U value requirements. See sections 10.2 and 10.3 of this Certificate. Technical Specification Table 1 Slab characteristics and use 4 Description 4.1 Crown Dritherm consists of layers of resinbonded, water-repellent treated glass wool formed into a resilient slab using a phenol formaldehyde resin binder. 4.2 The slabs are 1200 mm wide and 455 mm high in the thicknesses and nominal densities shown in Table Tests on the finished product comprise: density dimensional accuracy fibre diameter rigidity binder content thermal conductivity. 2 Slab Slab Partial fill use Full fill use thickness density Thickness Thickness Cavity width (mm) (mm) (kgm 3 ) range range Nominal Permitted deviation In partial fill use only insulation retaining fixings approved by the BBA should be used. Names and addresses of suppliers of approved fixings are available from Owens-Corning Building Products (UK) Ltd and the BBA.

3 4.5 At the time of publication, the following insulation retaining fixings were approved for use with the partial fill slabs (see Figure 1): (1) Acceptable for insulation retaining and structural stability: Hemax 90 retaining tie ) fixed to vertical Red Diamond retaining clip ) twist ties to Vista Fix retaining clip ) BS 1243 : 1978 (2) Acceptable for insulation retention only (see section 13.2 of this Certificate) (1) : Ensu-tie retaining tie Hemax 85 retaining tie HA Light retaining tie Sowesco retaining tie Lexsuco retaining clip. (1) It should be noted that when the product is installed using those ties listed above as `acceptable for insulation retention only, additional vertical twist ties may be required for structural stability in accordance with BS 5628 : Part 3 : 1985, where the overall cavity width exceeds 75 mm. Figure 1 Wall ties, clips and washers Hemax 90 Hemax 85 HA light insulation retaining wall tie 5 Delivery and site handling 5.1 The product is delivered to site in polyethylene packs. Each pack carries a label bearing the manufacturer s name, product description, essential instructions for installation, and the BBA identification mark incorporating the number of this Certificate. 5.2 Packages must be stored under cover until required for use. Ensu-tie with retaining clip Lexsuco clip with retaining washer 3

4 Design Data 6 General 6.1 When installed in accordance with this Certificate, Crown Dritherm is effective in reducing the U value (thermal transmittance) of new external cavity walls with masonry inner and outer leaves, where masonry includes clay and calcium silicate bricks, concrete blocks, natural and reconstituted stone blocks. It is essential that such walls are designed and constructed to incorporate the precautions given in this Certificate to prevent moisture penetration. 6.2 Buildings subject to the Building Regulations 1991 (as amended 1994) (England and Wales), the Building Standards (Scotland) Regulations 1990 (as amended) or the Building Regulations (Northern Ireland) 1994 (as amended 1995) should be constructed in accordance with the relevant recommendations of BS 5628 : Part 3 : In particular clause 21 of the Code of practice Exclusion of moisture should be followed where the designer should select a construction appropriate to the local wind-driven rain index paying due regard to the design detailing, workmanship and materials to be used. The relevant recommendations of BS 5390 : 1976(1984), Section 3 should be followed where the wall incorporates stone or cast stone. 6.3 Other buildings not subject to any of the Regulations mentioned in section 6.2 should also be built in accordance with BS 5628 : Part 3 : 1985 and/or BS 5390 : 1976(1984). 6.4 The use of cavity battens and/or boards during construction is strongly recommended to prevent bridging by mortar droppings (see Figure 4). 6.5 It is recommended that installation is carried out to the highest level on each wall or that the top edge of the insulation is protected by a cavity tray. 6.6 As with all cavity wall insulation, the construction detailing should comply with good practice described in the BBA joint publication Cavity Insulation of Masonry Walls Dampness Risks and How to Minimise Them. 6.7 The product is for use in any exposure zone in buildings up to 25 metres in height, subject to conditions in this Certificate being met. However, the use of the product does not preclude the need to apply any external render coat or other suitable finish in severe exposure zones where such application would be normal practice. 6.8 As with any other form of cavity wall insulation, where buildings need to comply with NHBC standards or Zurich Municipal Technical Manual, specifiers should observe the requirements of these documents. 4 Partial fill use 6.9 Where a residual cavity width of 50 mm or greater is maintained, the product can be used in any exposure zone Where the walls of a building are to be 12 metres high or less, the minimum residual cavity width to be maintained during construction must be 25 mm. To achieve this requirement, a greater nominal residual cavity width may need to be specified at the design stage to allow for inaccuracies inherent in the building process. The specifier may either: (1) design a cavity width by consideration of the dimensional tolerances of the components which make up the wall by reference to the British Standards relating to the bricks, blocks and slabs or use the data from their respective manufacturers. In addition, allowance may need to be made for the quality of available building operatives and the degree of site supervision or control available, or (2) design a nominal residual cavity width of 50 mm (a residual cavity nominally 50 mm wide will be required by the NHBC, where normal standards of tolerance and workmanship are adopted) Where the walls of a building are between 12 and 25 metres high the width of residual clear cavity to be achieved is to be in excess of 50 mm, and the following requirements apply: (1) From ground level the maximum height of continuous cavity walls must not exceed 12 metres; above 12 metres the maximum height of continuous cavity wall must not exceed 7 metres. (2) The specifier must take extra care when detailing to ensure that the introduction of the insulation does not affect the weather resistance of the wall. More than average site supervision is recommended during the installation of the product. (3) The exposure factor must not exceed 120, calculated using BBA Information Sheet No 10 Methods of Assessing the Exposure of Buildings for Cavity Wall Insulation, available from the Certificate holder or the BBA. The calculation procedure is also contained in Appendix E of BS 5618 : (4) Where, for structural reasons, the cavity width is reduced, eg by the intrusion of ring beams, a minimum residual cavity width of 25 mm must be maintained and extra care must be taken with fixings and weatherproofing, eg inclusion of a cavity tray. Full fill use 6.12 The following design conditions have been taken from the BBA joint publication Cavity Insulation of Masonry Walls Dampness Risks and How to Minimise Them. They are particularly important in areas subject to severe or very severe driving rain:

5 (1) In full fill it should be ensured that the slabs fill the cavity and are built into the walls as construction proceeds. (2) The insulation thickness should remain constant where possible. Should any changes in thickness occur, vertically, a horizontal damp-proof cavity tray should separate each thickness change. (3) A minimum thickness of 50 mm should be maintained where possible. Where, for structural reasons, the insulation thickness is reduced by the intrusion of ring beams, etc, a minimum thickness of 25 mm of insulation should be maintained and the manufacturer s advice on fixing and weatherproofing should be specially sought. (4) Raked or recessed mortar joints should be avoided in high exposure areas Where the walls of a building are between 12 and 25 metres high, the following requirements also apply: (1) From ground level, the maximum height of continuous cavity must not exceed 12 metres. Above 12 metres, the maximum height of continuous cavity must not exceed 7 metres. (2) The area to be insulated must not be an infill panel in a framed structure. (3) The exposure factor must not exceed 120, calculated using BBA Information Sheet No 10 available from the Certificate holder or the BBA. The calculation procedure is also contained in Appendix E of BS 5618 : (4) Owens-Corning Building Products (UK) Ltd in association with the architect shall carry out a detailed programme of assessment of the project including an examination of the quality of installation as work progresses. Above average site supervision is recommended during installation. (5) Certification relates only to buildings where the Certificate holder has given written approval for use of the product in the specified building. 7 Properties in relation to fire 7.1 The product does not prejudice the fire resistance properties of the wall. 7.2 A sample of the product tested to BS 476 : Part 4 : 1970(1984) achieved the classification `Non-combustible. 7.3 For buildings subject to the Building Regulations 1991 (as amended 1994) (England and Wales) the full fill slabs may be used in buildings of every purpose group, whereas the use of partial fill slabs does not require the use of cavity barriers in the buildings of any purpose group provided the walls are constructed in accordance with Diagram 28 in Approved Document B For buildings subject to the Building Standards (Scotland) Regulations 1990 (as amended) and the Building Regulations (Northern Ireland) 1994 (as amended 1995) the product may be used in buildings of any occupancy where the use of the partial fill slab does not preclude the use of cavity barriers in building of any occupancy or purpose group as would be required in any cavity wall. 7.5 The product does not constitute a toxic hazard in fire. 8 Liquid water penetration 8.1 The requirements to resist rain penetration are defined in section In all situations it is particularly important to ensure during installation that: (a) wall ties and fixings are installed correctly and are thoroughly clean (b) excess mortar is cleaned from the cavity face of the leading leaf and any debris is removed from the cavity (c) mortar droppings are cleaned from the exposed edges of installed slabs. 8.3 Data obtained by the BBA confirm that a masonry wall incorporating the slabs, built to the requirements of BS 5628 : Part 3 : 1985, will not transmit water to the inner leaf. 8.4 Data obtained by the BBA also demonstrate that the product does not absorb water by capillary action; when the product is used in situations where it bridges the dpc in walls, dampness from the ground will not pass through provided the wall is detailed in accordance with the Technical Solution shown in 4.4(c) of Approved Document C, of the Building Regulations 1991 (as amended 1994) (England and Wales). 8.5 Data obtained by the BBA confirm that provided the wall incorporating the product is built in accordance with BS 5628 : Part 3 : 1985, it can satisfy Technical Standard G3.1 of the Building Standards (Scotland) Regulations 1990 (as amended) and Regulation C5 for compliance with the Building Regulations (Northern Ireland) 1994 (as amended 1995). 8.6 Data obtained also show that the product will satisfy Technical Standard G2.6 of the Building Standards (Scotland) Regulations 1990 (as amended) and Regulation C5 of the Building Regulations (Northern Ireland) 1994 (as amended 1995) where the product bridges the damp-proof course in the inner or outer leaf. 9 Water vapour penetration The product is not a water vapour control layer.

6 10 Thermal insulation 10.1 For the purpose of U value calculations to determine if the requirements of the Building (or other statutory) Regulations are met, the thermal conductivity ( value) of the insulation may be taken as follows: Slab thickness (mm) Thermal conductivity (Wm 1 K 1 ) The requirement for limiting the heat loss through the building fabric will be satisfied if the U values of the building elements do not exceed the maximum values in the relevant Elemental Approach given in: Approved Document L to the Building Regulations 1991 (as amended 1994) (England and Wales), or Part J of the Technical Standards for compliance with the Building Standards (Scotland) Regulations 1990 (as amended), or Technical Booklet F to the Building Regulations (Northern Ireland) 1994 (as amended 1995) Guidance is also given in these documents on selecting the thickness of insulation required to enable a wall to achieve the desired U value. Alternative approaches are also described which allow for some flexibility in design of U values for individual constructional elements For constructions subject to the Building Regulations 1991 (as amended 1994) (England and Wales) the effect of thermal bridges should be taken into account in any U value calculations. 11 Durability 11.1 The product is rot-proof and durable The product is dimensionally stable under varying conditions of temperature and humidity and will remain effective as an insulation for the life of the building, provided it is installed in accordance with this Certificate. 6

7 Installation 12 General 12.1 The walls are constructed leading with either inner or outer leaf with Crown Dritherm fixed to the cavity face of the leading leaf. In partial fill use it is recommended that the inner leaf be constructed ahead of the outer leaf, in that the slab is fastened to the cavity face of the inner leaf. This gives a slightly enhanced thermal performance. In full fill use it is recommended that the external leaf be constructed ahead of the internal leaf so that any mortar protruding into the cavity space from the back of the external leaf can be cleaned off before installing the slab. Supervision requirements for buildings over 12 metres in height and up to 25 metres in height 12.2 To comply with this Certificate, Owens- Corning Building Products (UK) Ltd s specialists experienced in site practice and installation will attend the site to provide demonstrations to ensure correct installation from the outset Adequate supervision of the installation must be maintained and Owens-Corning Building Products (UK) Ltd s specialists must have right of access to site to ensure correct installation. 13 Procedure Partial fill 13.1 The procedure for installing the product using wall ties acceptable for insulation retention and structural stability is as follows: (1) A section of the leading leaf is built with the first row of wall ties, at approximately 600 mm horizontal spacing, where the insulation is to begin. The first run of slabs may commence below damp-proof course level to provide some edge insulation for the floor (see Figure 2). (2) The leading leaf is then built up to a minimum height of 675 mm, with a second row of wall ties at 450 mm vertical spacing. It is essential that all wall ties slope downwards towards the outer leaf. The slabs are then compressed slightly between the upper and lower wall ties, behind the retaining clips or wheels to form a closely butt-jointed run (see Figure 2) Horizontal spacing of wall ties should be determined as follows: (1) Where insulation retaining ties/clips are sufficient for structural purposes, horizontal spacing should be 450 mm or 600 mm depending on the thickness of the thinner leaf. (2) Where additional vertical twist ties are required, insulation retaining ties/clips should be spaced at 600 mm horizontal centres to give adequate retention of the slabs whilst additional ties are spaced in accordance with BS 5628 : Part 3 : 1985 (see Figure 2) The other leaf is then built up to the level of the top of the slabs Successive sections of wall incorporating approved wall ties are constructed and Crown Dritherm installed as work proceeds up to the required height The procedure for installing the product using the penetration clip retaining system is as follows: (1) A section of the leading leaf is built with the first row of wall ties (vertical twist ties to BS 1243 : 1978) at approximately 600 mm horizontal spacing, where the insulation is to begin. The first run of slabs may commence below damp-proof course level to provide some edge insulation for the floor (see Figure 2). (2) The leading leaf is built up to a minimum height of 675 mm with a second row of wall ties at 450 mm vertical spacing. The ties are positioned at a 450 mm or 900 mm horizontal spacing, depending on the thickness of the thinner leaf. The slabs are compressed slightly between the upper and lower wall ties to form a closely butt-jointed run. The slabs are then retained against the leading leaf by the Lexsuco clips (see Figure 2), which are pressed lightly through the insulation and located in the `green mortar bed joint, except at dpc level where the clips may be located in the perpend joints. It is important that the mortar should have the correct consistency; it should be stiff enough to retain the clip yet soft enough to avoid any hammering into place. Three clips per slab are required at approximately 400 mm centres Where additional ties are required, at less than 450 mm vertical spacing, the slabs must be cut and neatly fitted around them. Under no circumstances should they be impaled over ties The slabs should be close butted at corners (see Figure 3). It is recommended that whole slabs should be used at corners, but if this is not possible the butting face should be factory cut. Mortar droppings 13.8 After each section of the leading leaf is built, excess mortar should be removed from the cavity face and mortar droppings cleaned from exposed edges of the installed slabs before installation of the next run of the product. Use of a cavity board is recommended to protect slab edges and make cleaning easier. Also, a cavity batten will protect the installed slabs and help to keep a cavity clean as the following leaf is built (see Figure 4). Cut pieces 13.9 The slabs can be cut, using a sharp knife to fit around windows, doors, air bricks, etc. It is essential that cut pieces completely fill the spaces for which they are intended and that no gaps are left in the insulation.

8 Figure 2 Partial fill fixing systems Figure 4 Removal of excess mortar Hemax vertical twist ties and retaining clips Excess mortar must be cleaned off as shown, a cavity batten or board will protect the installed slabs and keep the cavity clear (a) with Hemax 90 wall ties Hemax 85 insulation retaining ties/clips at 600 mm centres (a) with board additional vertical twist ties at 900 mm centres slab 1200 mm long (b) with insulation retaining ties (eg double triangle) or clips and additional vertical twist ties Lexsuco clips with retaining washers (b) with cavity batten vertical twist ties Figure 5 Building in the first row of slabs (c) with Lexsuco clips and vertical twist ties to BS 1243 : 1978 wall tie Figure 3 Slabs butted at corners Crown Dritherm Full Fill wall tie damp-proof membrane cavity fill floor slab 8

9 Full fill Walls are constructed in the conventional manner, with the first row of wall ties where the insulation is to begin, but not on the damp-proof course, and at approximately 600 mm horizontal spacing. The first run of slabs may commence below damp-proof course level to provide some edge insulation for the floor (see Figure 5) A section of the wall leaf is built up to a course above the next row of wall ties which are placed at the usual spacing of 450 mm vertically and not more than 900 mm horizontally The slabs are compressed slightly and placed between the upper and lower wall ties to form a closely butt-jointed run (see Figure 5) The drip on each of the upper wall ties is inserted into the top of the slabs. This is important to ensure that it functions correctly (see Figure 6) The other leaf is built up to the same level as the slabs, with its inner face in contact with the slabs (see Figure 6) Successive sections of wall, incorporating wall ties, are constructed and the slabs installed as work proceeds up to the required height After each section of the wall leaf is built, excess mortar should be removed and mortar droppings cleaned from exposed edges of the installed slab [see Figure 4(a)] before installation of the next section of slabs It is recommended that 50 mm, 65 mm and 75 mm thick slabs are bent round corners (see Figure 7). Thicker slabs should be close butted to avoid cold bridges Where openings such as doors and windows are in close proximity it is recommended that a continuous lintel is used. Individual lintels should have stop-ends The slabs can be cut with a sharp knife to fit windows, doors, apertures, air bricks, etc It is essential that cut pieces completely fill the spaces for which they are intended and no gaps must be left in the insulation (see Figure 8) Small pieces must be fitted with the fibre layer parallel to the plane of the wall The slabs should always be installed to the highest level of each wall If installation of slabs is terminated at any other levels, the top edge of the insulation must be protected by a cavity tray and alternate perpend joints raked out to provide adequate drainage of water from this tray. Protection All building involving the slabs, particularly work which is interrupted, must conform to BS 5628 : Part 3 : 1985, sections 4.30 Storage on site, 4.35 Protection against damage, and 4.36 Supervision. 9 Figure 6 Crown Dritherm Full Fill wall tie Figure 7 Figure 8 window dpc Wall tie drips positioned in centre of slabs Slabs bent round corners Crown Dritherm Full Fill inner leaf inner leaf Use cut pieces to fill any gaps. The fibre layers must be parallel with the wall

10 Technical Investigations Bibliography The following is a summary of the technical investigations carried out on Crown Dritherm. 14 Tests Tests were carried out to determine: density resistance to water penetration water uptake at saturation water absorption at high relative humidity dimensional accuracy efficiency of fixing the system effect on the water resistance of the cavity wall with the slabs installed (full fill). 15 Other investigations 15.1 A re-examination was made of the data on which the previous Certificates were based Regular factory inspections have been carried out to ensure that quality is being maintained No failure of the product in use has been reported to the BBA. BS 476 Fire tests on building materials and structures Part 4 : 1970(1984) Non-combustibility test for materials BS 1243 : 1978 Specification for metal ties for cavity wall construction BS 5390 : 1976(1984) Code of practice for stone masonry BS 5618 : 1985 Code of practice for thermal insulation of cavity walls (with masonry or concrete inner and outer leaves) by filling with ureaformaldehyde (UF) foam systems BS 5628 Code of practice for use of masonry Part 3 : 1985 Materials and components, design and workmanship 10

11 Conditions of Certification 16 Conditions 16.1 Where reference is made in this Certificate to any Act of Parliament, Regulation made thereunder, Statutory Instrument, Code of Practice, British Standard, manufacturer s instruction or similar publication, it shall be construed as reference to such publication in the form in which it is in force at the date of this Certificate The quality of materials and the method of manufacture have been examined and found satisfactory by the BBA and must be maintained to this standard during the period of validity of this Certificate. This Certificate will remain valid for an unlimited period provided: (a) the specification of the product is unchanged; and (b) the manufacturer continues to have the product checked by the BBA This Certificate will apply only to the product that is installed, used and maintained as set out in this Certificate In granting this Certificate, the BBA makes no representation as to: (a) the presence or absence of patent or similar rights subsisting in the product; and (b) the legal right of Owens-Corning Building Products (UK) Ltd to market, install or maintain the product; and (c) the nature of individual installations of the product, including methods and workmanship It should be noted that any recommendations relating to the safe use of this product which are contained or referred to in this Certificate are the minimum standards required to be met when the product is used. They do not purport in any way to restate the requirements of the Health & Safety at Work etc Act 1974, or of any other statutory or Common Law duties of care, or of any duty of care which exist at the date of this Certificate or in the future; nor is conformity with such recommendations to be taken as satisfying the requirements of the 1974 Act or of any present or future statutory or Common Law duties of care. In granting this Certificate, the BBA does not accept responsibility to any person or body for any loss or damage, including personal injury, arising as a direct or indirect result of the use of this product. In the opinion of the British Board of Agrément, Crown Dritherm is fit for its intended use provided it is installed, used and maintained as set out in this Certificate. Certificate No 95/3212 is accordingly awarded to Owens-Corning Building Products (UK) Ltd. On behalf of the British Board of Agrément Date of issue: 14th February 1996 Director 11

12 British Board of Agrément P O Box No 195, Bucknalls Lane Garston, Watford, Herts WD2 7NG Fax: For technical or additional information, tel: For information about Agrément Certificate validity and scope, tel: Hotline: