H11 Curtain walling
	To be read with Preliminaries/ General conditions.
	TENDERING
	10	INFORMATION TO BE PROVIDED WITH TENDER
	•	 Submit the following curtain walling particulars: 
	-	Typical plan, section and elevation drawings at suitable scales. 
	-	Typical detailed drawings at large scales, including All Elevations . 
	-	Technical information and certification demonstrating compliance with specification of 
	proposed incorporated products and finishes, including Insulated Safety Glass .            
	-	Certification, reports and calculations demonstrating compliance with specification of 
	proposed curtain walling. 
	-	Proposals for connections to and support from the building structure and building 
	components. 
	-	Proposals for amendments to primary supporting structure and for secondary supporting 
	structure additional to that shown on preliminary design drawings. 
	-	Schedule of builder's work, special provisions and special attendance by others. 
	-	Examples of standard documentation from which project quality plan will be prepared. 
	-	Preliminary fabrication and installation method statements and programme. 
	-	Schedule of products and finishes with a design life expectancy less than that specified 
	in clause 440, with proposals for frequencies and methods of replacement. 
	-	Proposals for replacing damaged or failed products. 
	-	Areas of non-compliance with the specification. 
	TYPES OF CURTAIN WALLING
	110	CURTAIN WALLINGAs detailed in Architects Drawings
	•	 Supporting structure: Masonary/Steelwork as designed and detailed by a Structural 
	Engineer and subject to their reports . 
	•	 Curtain walling system: 
	-	Manufacturer: Comar Architectural Aluminium Systems Unit 5, The Willow Centre, 17 
	Willow Lane, Mitcham. CR4 4NX
	Tel:020 8685 9685. F:020 8646 5096, projects@parksidegroup.co.uk, www.comar-
	alu.co.uk . 
	Product reference: Comar 6 Curtain Walling System or Comar 6EFT Curtain Walling 
	System, using ???? mullions, and ???? transoms as per Comar wind loading 
	calculations,   	 . 
	-	Type: Comar ???? Pressure Equalised Thermally Broken, Stick Build System  . 
	•	 Internal framing member: 
	-	Material: Extruded aluminium profiles of aluminium alloy 6063 T5, T6 to BS EN 755-1: 
	2008 . 
	-	Finish: Powder coating . 
	Colour/ texture: RAL???/Anodised??? . 
	Minimum film thickness: ???? . 
	•	 External cover cap: 
	-	Material: Extruded aluminium profiles of aluminium alloy 6063 T5, T6 to BS EN 755-1: 
	2008 . 
	-	Finish: ________ . 
	Colour/ texture: RAL???/Anodised??? . 
	Minimum film thickness: ???? . 
	•	 Glazing: ??mm Insulating Saftey Glass Units with a 16mm Argon filled cavity . 
	-	Inner pane: tba . 
	-	Outer pane: tba . 
	•	 Glazing system: EPDM Gaskets, cover plate fixed or Silicone Jointed/Joint Gasket part no 
	2175 EPDM . 
	•	 Panel/ facing type: TBA . 
	-	External material: TBA . 
	-	External finish: TBA . 
	-	Internal material: TBA . 
	-	Internal finish: TBA . 
	-	Core insulation: TBA . 
	•	 Accessories: Perimeter flashings . 
	•	 Incorporated components: Comar ???? Windows, Comar ???? Doors . 
	•	 Other requirements: None . 
	140	LOUVRES
	•	 Manufacturer: Comar Architectural Aluminium Systems Unit 5, The Willow Centre, 17 
	Willow Lane, Mitcham. CR4 4NX
	Tel:020 8685 9685. F:020 8646 5096,Projects@parksidegroup.co.uk www.comar-
	alu.co.uk . . 
	-	Product reference: Comar Duco ???? . 
	•	 Material: Aluminium ISO 209-80:6063 . 
	•	 Finish: _______ . 
	-	Colour/ texture: _______ . 
	-	Minimum film thickness: _______ . 
	•	 Fixing: ________ . 
	•	 Other requirements: _______ . 

	150	MATERIALS SPECIFICATION
	•	 Minimum 'BRE Green Guide to Specification' online rating: ________. 
	•	 Specification of glazing materials to be in accordance with guidance in CIRIA document 
	'Glazing at height'. 
	GENERAL REQUIREMENTS/ PREPARATORY WORK
	210	DESIGN
	•	 Curtain walling and associated features: Complete the detailed design. Submit before 
	commencement of fabrication. 
	•	 Related works: Coordinate in the detailed design. 
	215	DESIGN PROPOSALS
	•	 Submission of alternative proposals: Preliminary design drawings indicate intent. Other 
	reasonable proposals will be considered. 
	220	SPECIFICATION
	•	 Compliance standard: The Centre for Window and Cladding Technology (CWCT) 
	'Standard for systemised building envelopes'. 
	•	 Reference information: For the duration of the contract, keep available at the design office, 
	workshop and on site copies of: 
	-	The CWCT 'Standard for systemised building envelopes'. 
	-	Publications invoked by the CWCT 'Standard for systemised building envelopes'. 
	230	INFORMATION TO BE PROVIDED DURING DETAILED DESIGN STAGE
	•	 Submit the following curtain walling particulars: 
	-	A schedule of detailed drawings and dates for submission for comment. 
	-	A schedule of loads that will be transmitted from the curtain walling to the structure. 
	-	Proposed fixing anchor details relevant to structural design and construction. 
	-	A detailed testing programme in compliance with the Main Contract master programme. 
	-	A detailed fabrication and installation programme in compliance with the Main Contract 
	master programme. 
	-	Proposals to support outstanding applications for Building Regulation consents or 
	relaxations. 
	235	INFORMATION TO BE PROVIDED BEFORE COMMENCEMENT TESTING OR 
	FABRICATION OF CURTAIN WALLING
	•	 Submit the following curtain walling particulars: 
	-	Detailed drawings to fully describe fabrication and installation. 
	-	Detailed calculations to prove compliance with design/ performance requirements. 
	-	Project specific fabrication, handling and installation method statements. 
	-	Certification for incorporated components manufactured by others confirming their 
	suitability for proposed locations in   the curtain walling. 
	-	Recommendations for spare parts for future repairs or replacements. 
	•	 Recommendations for safe dismantling and recycling or disposal of products. 

	DESIGN/ PERFORMANCE REQUIREMENTS
	311	INTEGRITY
	•	 Requirement: The curtain walling must resist wind loads, dead loads and design live loads, 
	and accommodate deflections and movements without damage. 
	•	 Design wind pressure:   	________. 
	•	 Hard body impact loads: In accordance with CWCT TN75: 
	-	Location and category: ________. 
	•	 Soft body impact loads - curtain walling to BS EN 14019: 
	-	Location and classification:   ________. 
	•	 Soft body impact loads - glass to BS EN 12600: 
	-	Location and classification: ________. 
	•	 Permanent imposed loads:   	________. 
	•	 Temporary imposed loads: ________. 
	312	INTEGRITY
	•	 Requirement: The curtain walling must resist wind loads, dead loads and design live loads, 
	and accommodate deflections and movements without damage. 
	•	 Design wind pressure: Calculate in accordance with BS 6399-2, Standard Method: 
	-	Basic wind speed (Vb): ________. 
	-	Altitude factor (Sa): ________. 
	-	Direction factor (Sd): ________. 
	-	Seasonal factor (Ss): 1. 
	-	Probability factor (Sp): 1. 
	-	Terrain and building factor (Sb): ________. 
	-	Size effect factor (Ca): 1. 
	-	External pressure coefficients (Cpe): ________. 
	-	Internal pressure coefficients (Cpi): ________. 
	-	Dominant opening: ________. 
	•	 Hard body impact loads: To BS 8200: 
	-	Location and category:   	________. 
	•	 Soft body impact loads - curtain walling to BS EN 14019: 
	-	Location and classification:   ________. 
	•	 Soft body impact loads - glass to BS EN 12600: 
	-	Location and classification: ________. 
	•	 Permanent imposed loads: ________. 
	•	 Temporary imposed loads: ________. 
	320	DEFLECTION UNDER DEAD LOADS
	•	 Requirement: Framing members parallel to the curtain walling plane must not: 
	-	Reduce glass bite to less than 75% of design dimension. 
	-	Reduce edge clearance to less than 3 mm between members and immediately adjacent 
	glazing units, panel/ facing units or other fixed units. 
	-	Reduce clearance to less than 2 mm between members and movable components such 
	as doors and windows. 
	340	AIR PERMEABILITY
	•	 Requirement: Permissible air leakage rates of 1.5m³/hr/m² for fixed lights and 2.0 
	m³/hr/lin.m for opening lights must not be exceeded when the curtain walling is subjected 
	to the peak test pressure. 
	•	 Permeability class to BS EN 12152:   A4. 
		Peak test pressure:   	600 Pa. 

	350	WATER PENETRATION
	•	 Watertightness class to BS EN 12154: R7. 
	-	Peak test pressure: 600 Pa. 
	•	 Additional requirements: n\a. 
	370	THERMAL PROPERTIES
	•	 Method of calculating the thermal transmittance (U-value) of curtain walling/ each zone of 
	curtain walling: Weighted U-value. 
	•	 Average U-value of curtain walling:   ________. 
	•	 Curtain wall zone interfaces: Co-ordinate to achieve required average U-value. 
	•	 Method for assessing thermal transmittance (U-value) of assemblies: By calculation. 
	385	THERMAL STRESS IN GLAZING
	•	 Glass panes/ units: Must have adequate resistance to thermal stress generated by 
	orientation, shading, solar control and construction. 
	425	INTERNAL SURFACE SPREAD OF FLAME OF CURTAIN WALLING
	•	 Standard: To BS 476-7. 
	-	Class 0. 
	440	DURABILITY
	•	 Relevant agents or degradation mechanisms:   ________. 
	•	 Design life of the curtain walling system: Not less than 30 years. 
	•	 Secondary components: Submit details together with required maintenance regime, 
	replacement periods and methods of replacement. 
	450	SAFETY
	•	 Finished surfaces of curtain walling: Accessible internal and external areas must not: 
	-	Have irregularities capable of inflicting personal injury. 
	-	Release irritant or staining substances. 
	TESTING
	510	COMPARISON (TYPE) TESTING
	•	 Requirement: To CWCT 'Standard for systemised building envelopes', Part 8. 
	•	 Test results and reports: Before commencement of curtain walling fabrication and 
	installation, submit proof of compliance with this specification. 
	530	TESTING AUTHORITY
	•	 Requirement: Project testing must be carried out by a United Kingdom Accreditation 
	Service (UKAS) approved independent laboratory. 
	PRODUCTS
	710	ALUMINIUM ALLOY FRAMING SECTIONS
	•	 Standard: To relevant parts of BS EN 515, BS EN 573, BS EN 755 and BS EN 12020. 
	•	 Alloy, temper and thickness: Suitable for the application and specified finish. 
	•	 Structural members: To BS 8118. 
	712	ALUMINIUM ALLOY SHEET
	•	 Standards: To relevant parts of BS EN 485, BS EN 515 and BS EN 573. 
	•	 Alloy, temper and thickness: Suitable for the application and specified finish. 
	732	ADHESIVES
	•	 General: Not degradable by moisture or water vapour. 

	735	FIXING ANCHORS
	•	 Type and use: Reviewed and approved by fixing manufacturers. Submit confirmatory 
	information on request. 
	•	 Dimensions: Not less than recommended by their manufacturers. 
	•	 Adjustment capability: Sufficient in three dimensions to accommodate building structure 
	and curtain walling fabrication/ installation tolerances. 
	737	GLASS GENERALLY
	•	 Standards: To BS 952 and relevant parts of: 
	-	BS EN 572 for basic soda lime silicate glass. 
	-	BS EN 1096 for coated glass. 
	-	BS EN 1748 for borosilicate glass. 
	-	BS EN 1863-1 for heat strengthened soda lime silicate glass. 
	-	BS EN 12150 for thermally toughened soda lime silicate glass. 
	-	BS EN 13024 for thermally toughened borosilicate glass. 
	-	BS EN ISO 12543 for laminated glass. 
	•	 Selection of glass type and thickness in accordance with recommendations of CIRIA 
	publication 'Glazing at height'. 
	•	 Glass quality: Clean and free from obvious scratches, bubbles, cracks, ripplings, dimples 
	and other defects. 
	•	 Glass edges: Generally undamaged. Shells and chips not more than 2 mm deep and 
	extending not more than 5 mm across the surface are acceptable if ground out. 
	739	DIMENSIONAL TOLERANCES ON GLASS
	•	 Measurement of tolerances: Before any thermal toughening/ heat strengthening. 
	•	 Pane dimensions less than 1500 mm: 
	-	For 3 to 6 mm thick glass: ± 1.0 mm. 
	-	For 8 to 12 mm thick glass: ± 1.5 mm. 
	-	For 15 mm thick glass: ± 2.0 mm. 
	-	For 19 mm and 25 mm thick glass: ± 2.5 mm. 
	•	 Pane dimensions more than 1500 mm: 
	-	For 3 to 6 mm thick glass: ± 1.5 mm. 
	-	For 8 to 12 mm thick glass: ± 2.0 mm. 
	-	For 15 mm thick glass: ± 2.5 mm. 
	-	For 19 mm and 25 mm thick glass: ± 3.0 mm. 
	•	 Pane squareness: Not more than 4 mm difference in diagonal measurements. 
	741	DISTORTIONAL TOLERANCES ON GLASS
	•	 Measurement of tolerances: After any thermal toughening/ heat strengthening. 
	•	 Maximum bow: 0.2% of pane dimension. 
	•	 Maximum roller wave: 
	-	For 3 to 5 mm thick glass: 0.5 mm. 
	-	For 6 to 10 mm thick glass: 0.3 mm. 
	-	For 12 mm and thicker glass: 0.15 mm. 
	•	 Maximum edge dip: 
	-	For 3 to 5 mm thick glass: 0.8 mm. 
	-	For 6 to 10 mm thick glass: 0.5 mm. 
		For 12 mm and thicker glass: 0.25 mm. 

	745	INSULATING GLASS UNITS
	•	 Standard and labels for hermetically sealed units: To BS EN 1279. 
	•	 Label: Each pane. 
	•	 Colour of aluminium perimeter spacers:   Natural. 
	•	 Perimeter taping: Not to be used. 
	•	 Perimeter seals: 
	-	Resistant to UV light degradation on exposed edges. 
	-	Compatible with structural, assembly and weather sealants. 
	760	GASKETS
	•	 Material: 
	-	Noncellular rubber to BS 4255-1. 
	-	Cellular rubber to ASTM-C509. 
	•	 Continuity: Outer gaskets of single front sealed curtain walling systems and inner gaskets 
	of drained and ventilated or pressure equalized curtain walling systems must be formed in 
	a complete frame with sealed joints. Vulcanized rubber gaskets must have factory moulded 
	corner joints. 
	•	 Durability: Resistant to oxidation, ozone and UV degradation. 
	770	GENERAL SEALANTS
	•	 Selection: In accordance with BS 6213 from: 
	-	Silicone. 
	-	One part polysulfide. 
	-	Two part polysulfide. 
	-	One or two part polyurethane. 
	•	 Classification and requirements: To BS EN ISO 11600. 
	•	 Reaction to contact products and finishes: Stable and compatible. 
	772	CURTAIN WALLING JOINT ASSEMBLY SEALANTS
	•	 Material: One part, low modulus silicone to BS EN ISO 11600, type F or G. Neutral curing 
	where in contact with or close proximity to other products that may be adversely affected 
	by acetoxy curing. 
	•	 Manufacturer: Contractor's choice. 
	-	Product reference: ________. 
	775	BONDING SEALANTS FOR STRUCTURAL SEALANT GLAZING
	•	 Material: Silicone, neutral curing, designed and manufactured for bonding of structural 
	sealant glazing. Compatible with contact and close proximity products and finishes. 
	•	 Manufacturer: ________ . 
	-	Product reference: ________ . 
	777	WEATHERSEALING FOR STRUCTURAL SEALANT GLAZING
	•	 Material: Silicone, one or two part, neutral curing. Designed and manufactured for 
	weathersealing of structural sealant glazing. Compatible with contact and close proximity 
	products and finishes. 
	•	 Manufacturer: ________ . 
	-	Product reference: ________ . 
	•	 Colour: _______ . 
	FINISHES
	830	POWDER COATING
	•	 Requirement: As section Z31. 

	840	ANODIZING
	•	 Requirement: As section Z33. 
	FABRICATION AND INSTALLATION
	910	GENERALLY
	•	 Electrolytic corrosion: Prevent. Submit proposed methods. 
	•	 Fixings: Concealed unless indicated on detailed drawings. Where exposed they must 
	match material and finish of the products fixed. 
	•	 Fabrication: Machine cut and drill products in the workshop wherever possible. 
	•	 Identification of products: Mark or tag to facilitate identification during assembly, handling, 
	storage and installation. Do not mark surfaces visible in the completed installation. 
	915	GLAZING
	•	 Requirement: As section L40, unless specified otherwise in this section. 
	•	 Directional patterned/ wired glass: Generally fix parallel to surround and align adjacent 
	panes where seen together at close quarters. 
	917	FIXINGS/ ADHESIVES APPLICATION
	•	 Requirement: As section Z20, unless specified otherwise in this section. 
	920	SEALANT APPLICATION
	•	 Requirement: As section Z22, unless specified otherwise in this section. 
	925	STRUCTURAL SEALANT GLAZING
	•	 Working conditions: Prepare for and apply structural bonding sealant in a favourable 
	workshop environment.  	
	•	 Curing: Do not transport units until structural bonding sealant has adequately cured for the 
	period stated in the project specific approval. 
	930	ASSEMBLY
	•	 General: Carry out as much assembly as possible in the workshop. 
	•	 Joints (other than movement joints): Rigidly secured, reinforced where necessary and fixed 
	with hairline abutments. 
	•	 Displacement of components in assembled units: Submit proposals for reassembly on site. 
	935	OPENABLE WINDOWS IN NATURALLY VENTILATED BUILDINGS
	•	 Location: Over 10 m from sources of external pollution. 
	955	FIXING ANCHOR INSTALLATION
	•	 Site drilling or cutting into structure: Submit proposals for positions other than shown on 
	detailed drawings. 
	•	 Concrete supporting structure: 
	-	Cast-in inserts: Provide detailed locational information. Protect cavities in inserts from 
	entry of concrete. 
	-	Edge fixing distances: Not less than recommended by fixing anchor manufacturers. 
	•	 Corrective fabrication: Minimize. Where necessary, submit proposals. 
	970	CURTAIN WALLING INSTALLATION
	•	 Securing to fixing anchors: Through holes formed during fabrication only. 
	•	 Tightening mechanical fasteners: To manufacturer's recommended torque figures. Do not 
	overtighten fasteners intended to permit differential movement. 
	•	 Protective coverings: Remove only where necessary to facilitate installation and from 
	surfaces that will be inaccessible on completion. 

	980	INTERFACES
	•	 Flashings, closers, etc: Locate and form correctly to provide weathertight junctions with the 
	curtain walling. 
	982	IRONMONGERY
	•	 Assembly and fixing: Accurately, using fasteners with matching finish supplied by 
	ironmongery manufacturer.  
	•	 Completion: Check, adjust and lubricate as necessary to ensure correct functioning. 
	985	MAINTENANCE
	•	 Maintenance manual: Incorporate details within the Building Manual in accordance with 
	CWCT 'Standard for systemised building envelopes' clause 7.6.1. 
		Materials certification and test reports to be included: ________.