Updated: Jul 9
When it comes to making your chimney stack watertight, there are a lot of choices that can be used. Lead has been used on chimney stacks for years and in my opinion, is the number one material you can use. Lead is robust and can handle most weather. In the roofing industry lead is the most popular choice to use around the chimney stack. The lead should last around 60-70 years with little to no repairs over the years. Over the last few years, there is a lot of other imitation leads that had come onto the market, but in my opinion, you can't beat the real thing. You can get a number of different imitation leads and the only good thing I can really think of for using this product is when your lead keeps getting stolen.
If you have a problem with lead thieves in your area, the best imitation lead on the market is alto lead plus. Alto lead plus comes with a 20 years guarantee, but I don't think it would last that long. Alto lead plus looks like lead from a distance and out of all of the imitation leads, I believe this one is the best on the market.
You can find loads of different imitation lead on the market and some are easier than others to fit, but in my opinion, if real lead can be used I would use it as this will give the chimney stack the best finish.
What parts of my chimney stack will need leading
there are 3 main parts to a chimney stack that you need a lead on and these are the front back and sides. The front is called a lead apron, the sides are where your soakers and flashings go and the back is where your gutter back goes. All these need to be either sealed with a lead mate or pointed in sand and cement when finished.
A lead apron is a piece that sits on the front of the chimney stack and should sit 6 inches onto your chimney stack and 6 inches on either your slates or tiles. The lead apron can sometimes be shared with your next-door neighbor and if you are replacing your lead on the chimney stack, it should be replaced in one piece and both sides should be changed.
Lead soakers and flashing
The lead soakers are the pieces of lead that sit on the slates or tiles and go up the side of your chimney stack. This piece should also be 6 inches onto the slate/tiles and 6 inches up the side of your chimney stack. Depending on what slate or tile you are using this piece will be formed differently. On slate and flat tiles, you have to do the soakers in single soakers which take a little longer to do. If you are using a double roman tile you will able to cut the soakers and flashing out of one piece of lead. The lead soakers are cut into what you call a step flashing and sit on the side of your chimney stack.
This piece of lead should sit over the top of the soaker to do TV m a water-tight seal, this is the piece of lead that should be cut to sit inside of the brickwork on your chimney stack. The lead flashing should be either sealed into the brickwork with lead mate or pointed in with sand and cement.
Lead gutter back
The lead gutter back is the most important part of the lead work on the chimney stack. This is the piece of lead that will deal with the most water and when it comes to fitting it the lead should be a minimum of 18-inch code 4 lead.
The gutter back is formed to sit at the back of the chimney stack and curl around the side of the chimney stack to form a water-tight seal with your lead soakers.
Is lead expensive to buy and fit
yes, lead is the most expensive material you can buy for your chimney stack, but you will get years of value for your money. Imitation lead is prone to leaking and is not much cheaper to buy. Leading your chimney stack is not cheap as you will need scaffolding and when it comes to keeping your roof watertight there is no better material than lead for keeping your chimney stack leak free.
How much does it cost to lead a chimney stack?
The average price to lead a chimney stack in lead should be around£1150.00, this price will include scaffolding, material, and labor. If you was to do it in imitation lead, the cost would be around £995.00. As you can see there is not a bit price difference between them both but lead will last over 3 times longer on your roof.
What guarantee do you get with lead?
When we lead a chimney stack we give a 10 years guarantee with all our work, this covers material and labor.