Lead Work in Burwell

Expert Lead Work
in Burwell

Where lead sits on your roof and why it matters

Lead seals the vulnerable junctions that other roofing materials cannot handle reliably: the step and cover flashings around a chimney stack, the soakers interlaced with slates along an abutment wall, the valley where two roof pitches meet, and the apron that runs across the front face of a chimney. These are not decorative details. They are the points where water is most likely to enter the building if the seal breaks down.

When a lead junction fails, water does not always announce itself immediately. It may track along a timber for a considerable distance before it appears as a ceiling stain or a patch of damp on a chimney breast wall. By the time you notice it, some degree of timber or plasterwork damage has usually already occurred. Getting a roofer up to inspect the flashing early, rather than waiting to see how bad the stain gets, almost always saves money.

Repair or replace? How to think about the decision

Whether lead work should be repaired or replaced depends on two things: the condition of the existing lead, and why it has failed. These are separate questions, and both matter.

If a flashing has failed because the mortar pointing that holds it into the masonry joint has crumbled away, but the lead sheet itself is sound, in good thickness and properly dressed, then repointing the joint and re-wedging the lead in place is a perfectly good repair. There is no need to strip and relay sound lead. This kind of repair on a chimney stack typically costs £150 to £300 and, if the lead is in decent condition, it will perform well for years.

If, on the other hand, the lead has split, thinned through corrosion, been bodged with sealant or flashing tape at some point in the past, or was too thin when it was originally laid, then patching it further is false economy. Thin lead, typically Code 3 or below, splits at the folds and along dressed edges when it has been in place for several years and has experienced thermal expansion and contraction through many summers and winters. Patching splits in thin lead with tape or sealant will hold for a season, sometimes two, but the underlying problem remains.

Signs that repair is the right answer

• The lead sheet is Code 4 or Code 5 thickness and is not cracked or split
• The failure is at the mortar joint rather than in the lead itself
• The lead is dressed correctly against the masonry but has lifted slightly at one point
• The flashing is less than fifteen to twenty years old and was originally fitted properly
• The underlying timbers and felt beneath are dry and sound

In these cases, a targeted repair is good practice. Stripping and relaying sound lead unnecessarily adds cost with no benefit to the customer.

Signs that replacement is the right answer

• The lead is visibly thin, splitting along folds or at the edges where it was dressed into the masonry
• Previous repairs with sealant or tape are already failing
• The flashing has been patched more than once and is starting to look piecemeal
• The lead is corrugated or has lifted away from the roof surface at multiple points
• The original installation used mortar fillets rather than properly cut and dressed lead, and those fillets are cracking away
• The underlying felt or timbers are wet or damaged, meaning the roof needs to be opened up regardless

Mortar fillets deserve a particular mention. On older houses, the junction between a roof slope and a parapet or chimney was sometimes finished with mortar rather than lead. Mortar does not cope well with the movement that occurs at these junctions, and it will crack in time. When it fails, the proper solution is to cut out the mortar and fit correctly dressed lead flashings, not to repoint with fresh mortar and hope for the best.

What a replacement job involves

For a chimney flashing replacement, the roofer will strip the existing lead or mortar, rake out the bed joint in the brickwork to the correct depth, cut the new lead sheet to size, dress it against the masonry and into the joint, and fix it with lead wedges before pointing with fresh mortar. The lead should be installed in sections no longer than about 1.5 metres to allow for thermal movement without buckling or splitting.

On a valley replacement, the old lead is stripped back, the underlying timber boards or decking is checked and repaired where necessary, and new lead is laid in overlapping sections working up from the eaves. Valley lead should be Code 5 as a minimum given the volume of water it handles.

A full chimney flashing replacement on a standard domestic stack, including both the step flashings up the sides and the apron across the front, typically costs in the region of £400 to £700 depending on the size of the stack. A valley replacement runs from around £500 to over £1,000 for a longer run. These are lead-work costs; any timber repairs are additional.

How we approach the decision for homes in Burwell

When we inspect a lead junction before quoting, we look at the thickness and condition of the existing lead, how it was originally fixed, whether the masonry joint is sound, and what the timbers and felt beneath look like. We then give you a straight recommendation: repair or replace, with the reasoning behind it. If a repair will hold, we say so. If it will not, we explain why, and what the replacement involves.

We work across Haverhill and the surrounding area, including Burwell and neighbouring villages, as well as further afield to places such as Sudbury, Halstead and Saffron Walden. Call us to arrange a roof survey and get a clear answer on whether your lead work needs a repair or a full replacement.