Roof Exposure Check

This gives you guidance on how a roof in your position should be built. It is not a survey and it is not a quotation — exposure on a real building also depends on the ground it stands on and what is around it, which is exactly what the free site visit is for.

How close is the property to open water?

Straight-line distance, not driving distance.

On the seafrontFirst line of buildings, nothing between you and the water.Within half a mileYou can taste the salt on a rough day.One to three milesInland, but still getting coastal weather.More than three milesSheltered by distance and, usually, by land.

Which way does the main roof slope face?

Along this coast the weather almost always arrives from the south-west, off the Channel.

South-west, into the prevailing windThe weather side. This slope does the work.Another direction, but open and unshelteredExposed, without taking the worst of it.Not sureWe will work it out at the survey.Sheltered by a hill, a valley or other buildingsSomething is taking the wind before you do.

What is the roof covered with?

If it is a mix, choose whatever covers the largest area.

Natural slateWelsh slate covers most of the Victorian stock here.Concrete tilesHeavy and durable, but the surface weathers.Clay tilesLong-lived, though individually more brittle.Flat roof — felt, EPDM or GRPEdges and upstands are the weak point.Metal sheet or standing seamExcellent, provided the fixings suit the location.Not sureEasily identified from a photograph.

Roughly how old is the covering?

Since it was last stripped and re-covered, not since the house was built.

Under ten yearsShould be well within its working life.Ten to twenty-five yearsMiddle age. Worth knowing its condition.Twenty-five to forty yearsFixings are the thing to watch now.Over forty years, or never re-coveredNot necessarily a problem — but worth checking.Not sureVery common. We can usually date it on sight.

Please answer all four questions — the profile only means something with the full picture.

Four questions, about a minute

Why it matters

Four bands, and the difference between them is not small

A sheltered roof in the Weald at Horsham and a front-line roof on the Peacehaven clifftop are the same building materials doing completely different jobs. Everything below the covering — fixings, edge detail, underlay, flashing cover — has to change with the band.

We use this same scale on every survey and on every area page, so you can see roughly where your part of the coast sits before you even run the check.

The scale

ShelteredSevere

Sheltered — rainfall is the pressure, not salt.
Moderate — non-ferrous fixings, mechanically fixed edges.
High — clipped perimeters, dry-fixed ridge and verge throughout.
Severe — every slate mechanically fixed, no mortar anywhere.

About this tool

Fair questions about the answers

Where do these recommendations come from?

They are standard practice for building near the sea: non-ferrous fixings, mechanical fixing rather than mortar bedding at ridge and verge, clipped perimeter courses, and generous lead cover for wind-driven rain. The more exposed the position, the further up that list a roof needs to sit. Your actual roof gets a real specification at the survey.

Why does the direction the roof faces matter so much?

Because along this coast the weather overwhelmingly arrives from the south-west, off the Channel, and the front is open to it. A south-west-facing slope is doing several times the work of the slope behind it, which is why it is so common to find one side of a roof worn out and the other perfectly sound.

It says severe exposure. Does that mean my roof is about to fail?

Not at all. It means the roof is in a demanding position, and that the things which matter there are fixings, edges and detailing rather than which slate was chosen. Plenty of roofs in severe positions last decades — the ones that were specified for it.

Does the exposure band change what a job costs?

It changes the specification, and specification affects cost. What we will not do is quote you a number here. Every quote comes after somebody has actually looked at the roof, and it comes in writing.

Four bands, and the difference between them is not small

Fair questions about the answers

Get a free quote, and an honest opinion with it