Chapter one
Bay-fronted terraces north of Royal George Road
Small Victorian terraces share walls, chimneys and gutters, so a leak in one house often starts at a junction that belongs to two.
Mid Sussex's summary of its conservation areas says the land north of Royal George Road holds the largest concentration of small Victorian terraced housing in the district, many of the houses bay-fronted. Terraces like these were built close together and quickly, and a century and a half on the roof is one shared system: a run of slopes cut by chimney stacks, party walls and the little roofs over each bay. Water seldom fails in the middle of a slope. It gets in where one surface meets another, and a terrace has far more of those meetings than a detached house.
At a glance
- Bay roofs add flashings and fillets to check
- Code 4 lead is the usual flashing choice
- Removing a party-wall chimney needs notice

1.1 The bay roof and its junctions
A bay window carries its own small roof, usually lean-to or pitched, which meets the wall above through a flashing, the strip of lead that seals roof to wall. Where the bay roof turns a corner there are valleys and fillets too. Lead dressed too tight cracks as it warms and cools, and a cement fillet laid where lead should be cracks away from the brick in time. Both let water in behind the bay, and it shows as a stain on the ceiling of the front room, some way from the crack. Leadworx calls Code 4 the standard for everyday flashing, and MyJobQuote puts a lead flashing's life at over 80 years, which is reason enough to dress a repair properly once. Codes, thicknesses and dressing are set out on our lead roofing page. On a terrace we also look at the shared gutter line, since a blocked outlet at one house sends overflow down the wall of the next, and the stain appears in a home that has done nothing wrong.

1.2 Chimneys on a shared wall
In a terrace the stacks often rise from the party wall, the wall shared with the neighbour. Repointing or rebuilding a stack is routine work, and our chimney repairs page covers it. Taking a chimney breast out is a different matter: the Planning Portal says Building Regulations approval always applies, and under GOV.UK's party wall guidance, taking chimneys off a party wall means giving your neighbour notice well ahead of the start, in a window of two months to a year. If a stack is leaking, we look for the cause before anyone talks about removal. The answer is often a new flashing, or a repointed joint at the base of the stack. When a stack really is beyond repair, you hear that from us with photographs, and the neighbour's side is discussed before a scaffold goes up.
Typical UK costs for terrace roof faults
- Minor roof repair£100 to £300
- Lead patch on a chimney£150 to £250
- Moderate roof repair£500 to £1,000
- Chimney lead replaced, with scaffold£700 to £920
National guides only: your figure arrives as one written total after we have inspected and photographed the fault. Source: MyBuilder roof repair guide, updated 21/08/2026; MyJobQuote chimney lead guide, updated 22/09/26.




