I have to replace lead flashing on a conservatory roof which has been screed to the house render. Basic materials being a new roll of lead (you say mmmm that’s a good start) and of course a sealant and I have bought hall clips. Now the ? is the lead is not more than 3 mars in length. What is the best think to do just buy a ready mix bag of cement and get on with it. Pleas give me some good advice on other mixes for the cement (ie mortar plasticer ? Or any type of bonding material or would the ready mix have all the ingredients ?
Replace lead flashing
- Thread starter johnscts
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The lead should be fitted in lengths not exceeding 1500mm between laps.
Readymix mortar is not going to be the best for rendering. You need plastering sand and cement and a good blob of fairy liquid. Preferably machine mixed.
Render joint is likely to fail if it is on a south elevation and zero mitigation regards lap onto lead, ex-con issues and size of repair etc.
Thanks for your response the flashing that I need to replace is a little less than 3mtrs Can u clarify what would be the best mix. I am only going to go through and buy the materials in Wicks so need to know best cement and you talked about Plastering sand and what other sand ? Fairy liquid is not a problem. And I don’t want to buy a mixer for such a small job. So if you could give me the mixes required it would be much appreciated. I had a handyman service who supposedly a previous job on the other side of the conservatory
and they got away with murder as I was away visiting my daughter and instead of removing the old lead they just added a new piece on top of the old (I call it a botch job) thanks I await your resolution
and they got away with murder as I was away visiting my daughter and instead of removing the old lead they just added a new piece on top of the old (I call it a botch job) thanks I await your resolution
Good morning to Nose ... can you give me an idea of the mix required to do this small job ie amount of sand “ sharp? “ or builders sand ? and Plaster sand with the cement mix it isa smallish job with removing and installing approx 3 mtr length of lead. All I need to do is remove the old lead and channel in a new roll. I have noted the distances 1500mm lengths
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A few photos may help. You've talked about sealant (leadmate?) and channelling new lead in, so is the sand/cement for patching up? How old is the conservatory? Lead is not the easiest material for the inexperienced to work with and one of the (better quality) flashband type products may be better if the conservatory is well into its working life. Also, consider safe access on a roof that is unlikely to carry your weight!
Ok I took a pic awhile back just where I had a leak of rain coming through via the wall. Ok the problem I have as you can see is the crack in the house render; and the previous flashing was never addressed into the house wall. The lower end of the pic will sit on the polycarbonate sheeting. Sent both pics. Down pipe from main roof was removed temporary at that time.
is it a gable end where the conservatory meets the house or a lean to?
where the house is roughcast render finish sometimes its neater to fit a board to the wall with a chamfer on the top edge -then lead over than.
also sometimes it is easier to do the lead in 2 parts -the first goes over the cons wall and then bends up the house wall, then the 2nd piece dresses down over.
it looks to me as though the lead chase needs to be higher up.
if you use lead -do it in short sections or you will struggle to get it place -say metre lengths.
forming the bends is best done on the ground using timber boards to get a crisp clean bend.
do as little work to the lead as possible -the more you mess around, the more buckled it will end up looking, so work it gently.
when buying the lead -choose a roll that has had its end mashed up.
and good luck removing the label -for some reason they make the labels almost impossible to remove!
use patination oil -3 coats and both sides if you are worried about lead staining.
A picture from further back would be more helpful.
where the house is roughcast render finish sometimes its neater to fit a board to the wall with a chamfer on the top edge -then lead over than.
also sometimes it is easier to do the lead in 2 parts -the first goes over the cons wall and then bends up the house wall, then the 2nd piece dresses down over.
it looks to me as though the lead chase needs to be higher up.
if you use lead -do it in short sections or you will struggle to get it place -say metre lengths.
forming the bends is best done on the ground using timber boards to get a crisp clean bend.
do as little work to the lead as possible -the more you mess around, the more buckled it will end up looking, so work it gently.
when buying the lead -choose a roll that has had its end mashed up.
and good luck removing the label -for some reason they make the labels almost impossible to remove!
use patination oil -3 coats and both sides if you are worried about lead staining.
A picture from further back would be more helpful.
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Looks like you a fun job there.
Images seem to indicate that the existing flashing is just laid against the wall and not bonded into a mortar joint. Is it brick or block under the render? If Brick you need to find the first joint above the conservatory roof line and cut (chase) out the mortar to a depth of 3/4inch (20mm) - use an angle grinder. If block and the first join is not visible in up to 3inches above the conservatory roof then with your angle grinder cut a chase the full length of the rook + 2inches/50mm over on each side. If you are not used to lead work (and you have enough to spare) then I'd say 3 lengths rather than 2. You need to allow for 4 inches/100mm, better 6inches/150mm overlap per section.
Roll out your new lead and cut a piece to your working length. Lay out on a strong board. First bend is 5/8inch from one edge a sharp right angle. Turn the lead over, next bend is the distance from the grove in the wall to the top edge of the conservatory. This bend is not quite a right angle.
Remove the old lead and keep. Cut some strips about an inch wide and inch&1/2 long from the old lead fold into 3 layers - they are the holding 'wedges' you will probably have to flatten them.
Offer the new flashing up to the mortar slot and with a blunt wide cold chisel hammer wedges in at about 12 inch/300mm intervals. the end pieces should extend over the consevartory roof by about 2inches. Repeat to complete all the flashing.
With the Lead Dresser form the new lead to the wall and roof contours.
Renew the pointing hiding the wedges.
Images seem to indicate that the existing flashing is just laid against the wall and not bonded into a mortar joint. Is it brick or block under the render? If Brick you need to find the first joint above the conservatory roof line and cut (chase) out the mortar to a depth of 3/4inch (20mm) - use an angle grinder. If block and the first join is not visible in up to 3inches above the conservatory roof then with your angle grinder cut a chase the full length of the rook + 2inches/50mm over on each side. If you are not used to lead work (and you have enough to spare) then I'd say 3 lengths rather than 2. You need to allow for 4 inches/100mm, better 6inches/150mm overlap per section.
Roll out your new lead and cut a piece to your working length. Lay out on a strong board. First bend is 5/8inch from one edge a sharp right angle. Turn the lead over, next bend is the distance from the grove in the wall to the top edge of the conservatory. This bend is not quite a right angle.
Remove the old lead and keep. Cut some strips about an inch wide and inch&1/2 long from the old lead fold into 3 layers - they are the holding 'wedges' you will probably have to flatten them.
Offer the new flashing up to the mortar slot and with a blunt wide cold chisel hammer wedges in at about 12 inch/300mm intervals. the end pieces should extend over the consevartory roof by about 2inches. Repeat to complete all the flashing.
With the Lead Dresser form the new lead to the wall and roof contours.
Renew the pointing hiding the wedges.
Thanks for your detailed information, would never have thought about doing the bending at ground level. I think cutting it into 2 sections is enough . I am going to take another pic from a back bedroom window u will need to zoom in. Lastly the mixes I will need in the past I see lime being mentioned/ mortar plasticiser being mentioned; just need to get what I need out of wicks if possible and if you could recommend the mix of the render
Thank you both. I am sending a few updates in photos. Just removed a.gutter down pipe which was in the way and of course put everything back as it looks as though it is going to p... down again. Underneath the old lead is lead strips that are part of the conservatory structure which holds down the polycarbonate sheets which can be lifted up to replace the sheets and then press down to hold them down (so no screwing down or nailing is ever required
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