How Do I Choose Between Slate and Tile for a New Roof?

The usual way to answer this is a comparison table of cost, weight and lifespan. There is one below, because those things matter.

But there is a more reliable starting point, and it is particularly useful in Warrington because the town contains such a wide range of housing — everything from older town-centre property to a large amount of development following the new town designation in 1968. Ask what the house was built for. The structure was framed for the weight of a particular covering and the pitch was set for its characteristics, and going back to that is nearly always the technically straightforward option.

Georgian and Early Victorian Town-Centre Property

Almost certainly slate. Small units, fine courses, and a roof structure framed for a light covering.

• Best answer: natural slate.
• Reasonable alternative: relaying the original slates on new battens and underlay, if they are sound — good slate outlives its nails by a wide margin.
• Avoid: concrete tile. It is heavier than the structure was designed for, the units are far too large for the building, and on a period elevation it looks wrong from a long way off.
• Note: Warrington has conservation areas including Bewsey Street and Bridge Street. Inside one, a visible change of covering is worth raising with Warrington Borough Council before ordering anything.

Victorian and Edwardian Terraces and Semis

Usually slate originally, though a great many have been re-covered in tile since.

• Best answer: slate, if the budget allows. It suits the proportions, it is lighter than what may be on there now, and on a street of slate roofs it keeps the terrace reading as one thing.
• Reasonable alternative: fibre cement slate — lighter, cheaper, faster to lay, and much closer to slate in appearance than any tile.
• Workable: clay interlocking tile, where the pitch allows and the street is already mixed.
• Watch: if the roof is currently concrete tile on a structure built for slate, it has been carrying more than it was designed for. Worth a proper look at the timbers during the strip.

Inter-War Semis

The 1920s and 30s stock, and the era with the most genuinely open choice. These roofs were built with either clay tile or slate, and both work.

• Best answer: whichever it was. Clay plain tile and slate both suit the period.
• Good alternative: clay interlocking tile — holds its colour, because the colour is in the clay rather than sprayed on the surface.
• Pitch check: plain tiles need a notably steeper roof than interlocking tiles or slate. Measure before choosing.
• The hip factor: these roofs are typically hipped, so whatever you choose, there is a great deal of cutting and a lot of hip line. A small-unit covering cuts more neatly around a hip than a large interlocking tile does.

New Town and Later Estate Housing

Following the 1968 designation and after. These roofs were designed for concrete interlocking tile and there is usually no reason to fight that.

• Best answer: a modern interlocking tile. The structure was framed for it, the pitch was set for it, and it is the lowest-cost route.
• Worth considering: clay interlocking rather than concrete, if you care whether the roof still looks right in twenty-five years. Concrete tiles are coloured with a surface pigment that weathers away, leaving grey; clay holds its colour.
• Possible but expensive: slate. It is lighter and works at lower pitches, so there is no technical obstacle — but on a house that never had it, and in a street where nothing else does, it is a large amount of money for a result that may look out of place.
• Check the pitch: estate roofs are often at the shallower end, which narrows the tile choice and can rule out plain tiles entirely.

The Comparison, For Completeness

The Three Constraints That Override Preference

Pitch

Every covering has a minimum pitch below which it is not warranted, because below it wind-driven rain is pushed back up under the lap faster than the covering sheds it. Slate tolerates the lowest pitches; plain tiles need the steepest roofs. Measure before falling in love with anything.

Weight

Going lighter is never a structural problem. Going heavier — most commonly slate to concrete tile — means the rafters, purlins and wall plates should be assessed rather than assumed.

Heritage

A like-for-like renewal is not development at all under section 55 of the Town and Country Planning Act 1990, so it raises no planning question anywhere. A visible change of covering can. Warrington has no Article 4 direction, but it does have conservation areas, so check the position for your address before ordering.

And the Thing That Decides How Long It Lasts

Worth saying, because people choose on stated lifespan and roofs rarely fail because the covering wore out. They fail at the fixings, the battens, the underlay and the lead.

A well-detailed tiled roof will comfortably outlast a badly detailed slate one. Choose the covering for pitch, weight and period — then spend your attention on the specification underneath it, because that is what decides when you next do this.

More Roof Replacement Advice for Warrington

Roof replacement in Warrington →
All roof replacement guides →
Roof Replacement Cheshire →