Cardiff has more Victorian and Edwardian terraced housing than anywhere else in Wales, and those houses share a piece of design that causes more storm-related leaks than any single missing tile: the rear back-addition, and the valley gutter where its roof meets the main roof.
T & T Roofing South Wales repairs storm damage across Cardiff, from the terraces of Cathays, Roath, Canton and Grangetown to the interwar semis of the northern suburbs and the newer housing around the Bay. In the terraced stock in particular, the useful advice is to stop looking at the front slope and start looking at the back.
Below is what we are most often called to in Cardiff, roughly in the order it comes up. If what has happened to your roof is not on the list, call anyway — it is not an exhaustive list, it is the common ground.
The standard Cardiff terrace has a main roof running front to back and a narrower rear wing — the back-addition — running off it at right angles. Where those two roofs meet, they form an internal angle, and that angle is drained by a valley: a lined channel that carries water down between the two slopes.
A valley handles a large share of the roof's water through a narrow route. When it is clear and its lining is sound, it works faultlessly. When a storm fills it with leaves, moss or a displaced slate, water backs up, rises above the level of the covering either side and runs underneath it into the roof structure.
Why this catches people out. The leak shows inside, usually near the rear of the house or above the back bedroom, while the roof looks undamaged from the street. Nothing has blown off. The roof simply could not get rid of the water fast enough, and the water found another way.
Older valleys were lined in lead; later ones use other materials, and many Cardiff valleys have been repaired at some point with mortar or mastic. Those repairs are usually where a valley fails next, because rigid fillers crack while the roof around them moves.
Some Cardiff terraces, particularly the larger three-storey houses and those with rendered or decorative frontages, have parapet walls at the front or between properties, with the gutter concealed behind them. A concealed gutter has the same weakness as a valley and one extra: you cannot see it from the ground, so a blockage can sit there for months.
After a storm these are worth checking specifically, because storms deliver exactly what blocks them — leaves, twigs, moss dislodged from the roof and occasionally a piece of the roof itself.
Most of the Victorian and Edwardian stock is slated, and the familiar pattern applies: the slate outlasts the nails. When fixings corrode, slates slide rather than break, so you may find intact slates on the ground and a clean gap on the roof.
Cardiff terraces are often tall, with steep front slopes rising straight from the pavement. That makes assessment from the ground harder and makes it more important not to attempt it yourself from a ladder. A gap high on a steep slope is not something to inspect personally.
Large parts of Cathays, Roath and the streets around the universities are rented, often managed at a distance, and roofs in that situation tend to be dealt with when something goes wrong rather than before. That is not a criticism of anyone; it is simply why storm damage in those streets is often the second or third symptom rather than the first.
We work for landlords, letting agents and managing agents as well as owner-occupiers, and can provide a written report and quotation suitable for passing to a property owner or a block manager.
Cardiff terraces carry a great many chimney stacks, frequently shared on the party line and frequently disused. Disused stacks stay damp, and damp mortar weathers faster, so a stack that has not been used since central heating went in can be in poor condition while looking sound from below.
Storm damage typically shows as a leaning or loose pot, cracked flaunching, open joints in the brickwork, or lead flashing lifted where the stack passes through the roof. We assess the stack and the surrounding covering together, because repairing one and not the other rarely stops the water.
Cardiff has an enormous number of flat roofs on rear extensions, dormer conversions, bay windows and outbuildings. Wind attacks the perimeter details, and driven rain finds the upstand where the flat roof meets a wall.
Bay window roofs deserve a specific mention. They are small, often lead or felt, and sit directly above a window opening, so when one fails the water arrives inside quickly and visibly. They are also frequently overlooked in a roof inspection because they are not part of the main roof.
Where materials are loose above a street or water is entering a property, the immediate work is to reduce risk and limit damage. What is possible depends on conditions and access — in terraced streets that often means the practicalities of getting equipment to a rear roof as well as the weather.
Temporary measures buy time. They are not the repair, and we will always tell you which one we have carried out and what still needs doing.
We inspect the damage, identify the roofing work required and provide a written quotation. Where the cause is a blocked or failed valley rather than something the storm removed, we describe it accurately, because that is what your insurer is entitled to and because an inaccurate description tends to unravel later.
Whether the work is covered is a matter for your policy and your insurer.
That is the classic Cardiff terrace pattern and it usually points to the valley gutter between the main roof and the rear back-addition. A blockage there makes water back up and run under the covering, with no visible damage at all from the front.
Leaves, moss dislodged from the roof, twigs and debris brought down in the same storm, and sometimes a displaced slate that has slid into it.
Because the nails failed rather than the slate. Welsh slate frequently outlasts its fixings, so slates slide out intact once the nails have corroded through.
Yes. We can provide a written assessment and quotation suitable for passing to a property owner, agent or block manager.
Bay roofs are small, usually lead or felt, and sit directly over a window, so failures show up quickly indoors. They are also easy to miss in a general roof inspection, so it is worth mentioning specifically.
Usually, though access is one of the things we assess on arrival. In terraces the practicalities of getting equipment to a rear roof are part of the job and we will tell you what is involved.
No. Cardiff terrace front slopes are typically tall and steep and rise straight from the pavement. Photograph what you can see from the ground and leave the rest to us.
Five guides written specifically for Cardiff. We are publishing these in batches rather than all at once, so some are still being written — those are marked, rather than linked to a page that is not there.
We cover fifteen areas from our base in Neath. If yours is not listed, call and ask — the list is where we work most, not a boundary.
Tell us what the weather has done and what you can see from the ground. We will assess the roof, explain what needs repairing and give you a free, no-obligation quotation.
Tell us what the weather has done and what you can see from the ground. We will come back to you — usually the same day.
If water is coming in now, please call rather than email — 07766 547309.
