The short answer
Half-round is the usual choice for most houses, square suits modern and contemporary lines, and ogee suits period homes that want a moulded look. No profile is best for every roof. Capacity depends on the size of the channel, its fall and the outlets as much as on the shape, and on a listed or conservation area house the council may have a view, so check before ordering.
Three shapes and what each looks like
A half-round gutter is a simple curve, like a pipe cut along its length. It is the shape most people picture, and it works with a wide range of houses, from Victorian terraces to 1930s semis. Because the curve is smooth, debris tends to wash toward the outlet instead of lodging in corners.
A square profile has flat sides and a flat bed, and a crisp, boxy edge. It matches modern extensions, flat-fronted fascias and contemporary cladding, and it is often chosen to sit neatly against a deep fascia board. The corners of the channel are where silt tends to settle first, so square gutters benefit from regular clearing.
An ogee profile is moulded, with a front face shaped like a shallow S. It echoes the cast iron pattern seen on many nineteenth-century houses, and in uPVC or aluminium it gives a traditional look without the weight of iron. Ogee sits well against a plain fascia, and in a row of period houses it can keep the roofline consistent.
Capacity: what the shape does and does not decide
People often ask which profile carries the most water. The honest answer is that the shape matters less than the size of the channel, the fall towards the outlet and the number and position of outlets. A deep square section can hold more than a shallow half-round, and a large half-round can hold more than a small ogee. High-capacity versions of each shape exist for larger roofs.
The fall is just as important. Makers usually specify a slight tilt towards the outlet, about 1:600 to 1:350 depending on the system, as we explain in our answer on what fall a gutter should have. A well-set small gutter drains better than a large one lying flat.
We do not quote catchment calculations on this page, since a proper sizing check uses the roof area and the maker's tables. If your gutters overflow in downpours, look at the system as a whole, starting with blockages, outlets and downpipe positions, before changing the shape.
Matching the profile to the house
On a period house, the original profile is a clue to the right replacement. Many older terraces and cottages in the valleys had cast iron in half-round, or moulded patterns of the ogee type. Where the old gutters survive, matching the shape keeps the eaves line true to the building. Our guide to cast iron gutters on Stroud's period homes deals with repair and replacement of the originals.
On a stone house with a deep stone eaves course and no fascia, the gutter may be carried on brackets fixed into the masonry or the rafter ends. A profile that needs a plain flat fascia to look right can then be the wrong choice. Dressed stone, painted timber and plastic boards all give a different background, and we would look at the elevation before suggesting a shape.
On a newer house with a plastic fascia, a square or half-round profile in a matching colour is usually the simplest answer. For a mixed roofline, such as an old house with a modern extension, it is common to use one profile throughout so the lines read as a single scheme.
Listed buildings, conservation areas and consent
If your home is listed, gutters are part of its character, and altering them can need consent. Stroud District Council says its listed buildings have full legal protection, so ask the conservation team before changing the material or the shape.
Stroud District has 41 conservation areas, and five carry Article 4 Directions. Whether they reach gutters is unclear from the council's guidance, so put the question to the planning team. Our guide to gutters and fascias in Stroud's conservation areas covers how to approach it.
Why it matters in practice
A swap from half-round cast iron to square aluminium is a visible change to the front of a period house, and it is the kind of change a conservation officer notices. Like-for-like replacement is the approach we follow on older roofs, and where the profile or material is changing we would rather you checked first than discovered a problem after the work.
Cost, fixings and the next step
Profile affects price only modestly. MyBuilder's 2026 roofline price guide lists guttering at £30 to £70 per metre, with scaffold at £20 to £40 per m². The material and the finish move the price more than the shape does, and a heavier cast or moulded section costs more to buy and to hang. Access is often the largest single line on a two-storey house.
The fixings differ with the shape. Square and ogee sections usually use brackets matched to the profile, while half-round gutters are the most forgiving to fit. Spacing is set by the maker, as our answer on gutter bracket spacing explains, and a damaged or dished fascia behind a decorative profile is more noticeable than behind a plain one.
For a view of what each part of the eaves does, see our guide to fascias, soffits and gutters explained. To have us look at your house, use the form here or WhatsApp with a few photographs of the eaves. Our quote after the survey covers the whole job. See also the guttering, soffits and fascias overview. Our work carries a 10-year workmanship guarantee in writing.