Anyone with experience of installing Lead Flashing?

[Fat Tone]

My home extension is going well, and I have the roof frame up. Before I can install the polycarbonate glazing panels to the roof, I have to seal to the existing house wall.
This is done using 'step flashing' down each slope (it is an apex roof) with a thin sheet of lead. Apparently it is traditionally a plumbers skill, rather than e.g. a bricklayer.

I've manged to find some (rather poor) diagrams on the net to give me a clue, but no (good) descriptions of the process.

http://www.leadroof.org.uk/html/1402.html - for the steps
http://www.leadroof.org.uk/html/1407.html for the ridge

Can anyone offer any tips? This is one thing I can't afford to get wrong!

TIA

T.

[Brian Ellis]

In most countries lead is no longer permitted for flashing: check for where you are. All the flashing here is done with galvanised iron (usually) or copper and has been for many years. I would be astonished if the UK were behind Cyprus for this. In Switzerland, lead was forbidden over 50 years ago, as I remember.

Of course, you can also do flashing elsewhere

[Dr Mordrid]

You can use aluminum or galvanized steel, but IMO you're better off spending the extra for stainless steel or copper if you plan on staying in the house or the environment is harsh as they'll last the longest.

The layering goes; waterproof membrane, roofers felt, flashing then shingles with lots of roofing sealer where appropriate, meaning the metal to metal joints.

With step flashing the procedure varies according to how the vertical wall is finished. If possible the flashing should be slid under the existing siding on the vertical wall.

http://www.extremehowto.com/xh/article.asp?article_id=60348

Brick is of course a different story. Ideally with brick there should be a cap flash going into the mortar joints then folded down over the top of the vertical flashing, but this is only easy with new construction. Otherwise get ready to chisel/grind out the old mortar then replace it after shoving in the flashing...which hopefully you have already bent

This procedure is very much like flashing a chimney, so take your cues from that if you have one. Here's how to do a chimney;

http://www.rd.com/content/openContent.do?contentId=17758

If you're not up to that then glop on the sealer and hope for the best.

[Fat Tone]

Yup its lead here. There are options for strips of metal (not sure what) with adhesive backings, or just plain tape, but they generally have a much shorter life.

Thanks. This job is to a brick wall. What none of the sites tell you is 'how' to do it as per the pic I linked above.

I've removed the mortar with my grinder - a simple job once I figured out I could use my set-square on the roof section to mark the ends of the grooves, and I've just completed my 1st metre-long section. I'm sure the rest (3 more plus something different to go over the ridge) will go much faster. Its a case of working out how to transfer the measurements to the lead for cutting (and not losing your tin-snips half-way through!).

Edit: I'll be using lots of sealant too!

[Dr Mordrid]

The only place I see lead these days is car battery terminals and bullets

[The PIT]

Interesting as I saw a Roofer drive past and he was advertising Lead Flashing so perhaps it's still allowed here.

[Dr Mordrid]

I don't thinkl lead flashing is banned at the federal level, but I'm sure a lot of local codes have done so since you can't find it in too many places. There are lots of good alternatives anyhow. That said I can buy it in small bricks for molding bullets, musket/pistol balls etc. My melting pot will hold ~1 lb. batches.

[Fluff]

http://www.water.org.uk/static/files_archive/0Full_report.pdf

P39-40 regarding lead into sewers.

Inputs of lead from domestic activities are relatively small (around 1-
2% of the total). Over 95% of the lead from households comes from
faeces, because all of the food we eat contains natural amounts of
lead.

[Brian Ellis]

Be careful. DEFRA have lead flashing targeted for a regulatory impact assessment. According to http://www.defra.gov.uk/environment/...-ria/index.htm, they recognise that this would be costly, but this does not mean it would be prohibitive. Recent RoHS prohibition of lead in solder has cost literally billions, world wide, to the electronics industry, so there's no reason why the same would not be applicable to the building industry, even retroactively, meaning that existing lead would have to be replaced. It may be wise to consider an alternative.

Whatever, lead sheeting used for flashing is very crudely made and is usually very oxidised. Handling it will cause a transfer of lead oxides onto the skin and, being insoluble, is impossible to wash off, other than loose superficial stuff. As it is highly toxic, some is almost sure to transfer to food you handle over the following 24 hours or so (or cigarettes you handle). You would be well advised to have special gloves for this job.

I'm truly astonished that the UK has not forbidden lead flashing, many years ago. Whatever, and this is important, it is illegal to allow heavy metals into nature and landfills (except special chemical landfills according to EU Directives). Please make sure that any waste, surplus or offcuts is disposed of correctly to a lead recycler.

[The PIT]

Sort of brings up another issue disposal. Even if the dealer has the proper documention theres nothing really you can do to ensure he doesn't sell it off or it ends up with someone else who dumps it illegally.

Like all these computers we scrap legal but probably end up in landfill sites in Africa instead.

[Fat Tone]

I'm using gloves for sure! About 3/4 done now. The lead came as part of the 'kit' for the conservatory walls + roof.

I reckon I'm gonna have >10Kg to dispose of - I'll be looking for a suitable merchant to buy it off me.

[Brian Ellis]

Sort of brings up another issue disposal. Even if the dealer has the proper documention theres nothing really you can do to ensure he doesn't sell it off or it ends up with someone else who dumps it illegally.

Like all these computers we scrap legal but probably end up in landfill sites in Africa instead.

Lead is easily recycled: just think of all the car batteries. It would cost more to transport to Africa than it's worth.

The current value of pure virgin lead ingots is ~$1150/tonne. Wholesale scrap is usually about 1/3 this, so this would work out at ~$350/tonne. A scrap merchant will give you ~½ this for quantities less than 1 tonne, say, £0.10/kg, if you're lucky. Your 10 kg might bring you in a quid, then!

[Fat Tone]

Woohoo! A quid!!!

I'll donate it to murc

Actually I meant I wanted it to be recycled properly, not just end up in landfill. Mind you, our local minicipal tip is very hot on recycling now, so I'm sure it'll be dealt with properly there.