THE GUIDE TO GOOD LEADWORK

1 This booklet has been produced topromote and encourage the correct use oflead sheet flashings , weatherings andgutter linings in knows more about lead than Calder!THEGUIDE TOGOODLEADWORKC alder Booklet Doc No010 6/5/05 11:57 am Page 12 Leadsheet hasbeen inuse as sheet adorns theroofs of churches, offices,factories, public buildingsand homesthroughoutthe UnitedKingdombecauseof itsdurabilityand easeof Booklet Doc No010 6/5/05 11:57 am Page 23 Calder Booklet Doc No010 6/5/05 11:57 am Page 3 Thickness &weight chart5 Borra FixingClip 6 Lead SheetSealant7 Patination Oil8 Geotec Underlay,Wood Core Rolland Clips9 Clips10/11 Coverflashings12/13 Abutmentflashings14/15 Roll endsand drips16 Ridgesand hips17 Chimneyflashings18 Pitchedvalley gutters 19 Box andtapered gutters 20 Secret gutters 21 Flat roofcoverings22 Windowflashings23 CONTENTSNote: BS EN12588 replaced BS1178 in August 1999.

2 Calder leadsheet and flashing conforms to the new European booklet is a GUIDE to the correctdetailing and fixing of lead sheetflashings, weatherings and following information conformswith the British Standard for leadworkand the recommendations of the LeadSheet Association. For more detailedtechnical information, referenceshould be made to the LSA spublication entitled The CompleteManual which covers the manyapplications of lead sheet in sheet is a proven, long-lifebuilding material. It is extremelymalleable and can be readily dressedto fit the multi-curved contours ofmany modern building materials,particularly roofing tiles.

3 To ensurethis longevity, however, it isessential to follow a few basic rules: Individual pieces of lead sheetmust not exceed therecommendations set out on page5. In particular, each piece offlashing must be no longer Fixings should hold the leadsecurely in position withoutrestricting thermal flashings , regular expansionjoints (laps) will overcome therestriction caused by lead wedgingalong one side. Nails and screws should have asimilar life expectancy to that ofthe lead, therefore use copper,brass or stainless steel, nevergalvanised or aluminium fixings.

4 Joints must allow for thermalmovement but also remainweathertight for the position wherethey are used. For example, do notuse laps or welts to join pieces ofgutter lining. The correct joint is adrip, as illustrated on page , lead sheet is a fine, long-life material .. but only when used Booklet Doc No010 6/5/05 11:57 am Page 4 LEAD SHEETBS EN12588 Thicknesses to BS EN12588 tolerances of 5%Kg persquare metre:Thicknessin Calder GUIDE to Good LeadworkTable 1 Range of thicknesses and weightsTable 2 Thickness of lead sheet for various purposesUseBS EN12588 Code or 4 Apron and cover flashingsHip and ridge flashingsPitched valley guttersWeatherings to cornices, parapets etc.

5 4 or 5 Lead slatesChimney flashings - back gutters, apronand side flashingsParapet, box and tapered gutters5 to 8 Table 3 Sizing - guidelines to good practiceRecommended maximum sizes of individual pieces of lead for the following applications:3a flashings - apron and cover. Also pitched valley gutter liningsBS EN12588 UsesMaximumCode mm3 Soakers10004 and 5 flashings and pitched1500valley gutters3b Gutters - box, tapered and parapetBS EN12588 Maximum length Overall girthCode drips mmMax. mm41500750520008006225085072500900830001 0005 Calder Booklet Doc No010 6/5/05 11:57 am Page 56 BORRA FIXING CLIP the answer to fastening lead flashingUsing the clip will securely fasten the lead flashing in place inaccordance to BS6915.

6 The standard recommends that fixings arefixed at 450mm maximum Bisby March 2002, says: These two products will transformthe way lead is fixed. I wasamazed by just how well theclips work. I doubt that anyonewho cares about theirprofessional reputation and wantsto avoid callbacks will be usinglead wedges in another five years .For busy lead installers, time is money. These easy touse fixing clips will result in time Booklet Doc No010 6/5/05 11:57 am Page 67 Why is it that so many water penetration problemsoccur at abutments? The answer often is that mortar isnot a satisfactory long-term pointing where leadflashings turn into joints in brickwork or SHEET SEALANTthe answer to pointing problems!

7 The mortar is unable to adhere to both the brick and the lead whensubject to changes in temperature. It soon cracks, particularly insunny exposures, allowing water to penetrate, causing dampnessbelow. In many cases the problem is made worse by poor cleaningout of the joint which results in a wedge-shaped pointing whichquickly cracks away from the there is a practical, long-term alternative to mortar pointing -Lead Sheet Sealant. This one-part, neutral-cure, high-performancesilicone-based sealant has been specially formulated for use withlead sheet flashings and its elastic properties make it ideally suitedfor pointing between lead and brickwork or Sheet Sealant - The Experts Choice!

8 The sealant specifically designed for pointing joints betweenlead and brickwork or a long term, flexible joint, which can absorbtemperature the problems of pointing with wet mortar,particularly in hot or frosty , cleaner and easier to use than Lead Sheet Association recommends Booklet Doc No010 6/5/05 11:57 am Page 78 Lead sheet continues to be popular as an architecturalfeature on buildings because of its ease of use, durabilityand the pleasing grey colour of its protective OILprotective coating for new leadNEW FORMULATIONP atination oilspecificallydeveloped for theindustry by Calder onbehalf of the LeadSheet Association,minimises unsightlystaining and impartsa pleasing appearanceto newly applied leadsheet and thepatina formed on leadlooks patchy andunattractive.

9 In rainy or damp conditions new lead will quicklydevelop an uneven powdery white, non-adherent coating of leadcarbonate, a corrosion product, which is aestheticallyunacceptable. The staining of tiles and brickwork spoils the overallappearance of the oil will minimise this uncontrolled formation ofcarbonate, improve the hygiene on the job AND impart a pleasingappearance to the lead both before and after the formation of itsfinal the oil vigorously before the oil evenly with a soft absorbent cloth. Workhorizontally from top to bottom maintaining a wet lower not use a circular scrubbing the oil to allnewly installed lead items - large or the oil before any rain and at the end of the day s coat is all that is flashings and coat the underside of the lead for about50mm from the the lead beforeturning up clips around the to coat between : Because of the solvents it containsit is important to keep patination oilaway from roof areas where bituminousfelt has been laid, any spillage willdissolve the comprehensive LSA data sheet isavailable on tiles spoiled by run-off Booklet Doc No010 6/5/05 11.

10 57 am Page 89 GEOTECUNDERLAY prevents weardue to thermalmovementGeotec 220 PYunderlay is used toisolate sheet metalroofing fromsubstrates allowingmetal sheet toexpand andcontract 220PY is anon-woven, needlepunched, polyestertextile underlay,weighing 220g/m2,conforming to theLead SheetAssociation CORE ROLL as used on ridges, hips and flat roofingWood core roll is to be used to allow for the expansion andcontraction in lead sheet and core roll is used for joining bays of lead roofing, also onsteeply pitched roofs and lead cladding where a bold jointappearance is preferred. It is shaped to prevent wind to hold lead permanently in positionCut to the required length fixing clips are recommended in rolls,welts, standing seams and for the clipping of lap joints in copper, tinned copper and terne coated stainless UNDERLAY,WOOD CORE ROLL & CLIPS GEOTEC UNDERLAY WOOD CORE ROLL CLIPS Calder Booklet Doc No010 6/5/05 11:57 am Page 9 Lead clips are only suitable for sheltered exposures.