Reading a roof from the ground: eight things you can spot before calling anyone

Last month a homeowner in Bradford called a roofer about a leak. The roofer asked five questions: what is the pitch, what is the covering, where is the damage, how old is the roof, and is there access from the back? The homeowner could not answer any of them. The roofer said "I'll come and look, £80 callout fee." If the homeowner had spent five minutes on the pavement with this checklist, the call would have gone differently.

Before you phone a single roofer, you can answer half of what they'll ask you by standing in the street and looking properly at your own house. Five minutes, no ladder, no drone, no cost. The point isn't to diagnose the problem yourself — it's to give the roofer a brief that's useful, so the quote you get back is specific rather than a shrug.

A good visual brief saves a callout fee (£60–£150 for most UK roofers), saves quote time, and usually gets you a better price because the roofer doesn't have to pad the quote for unknowns they can see in your photos. What follows is a working checklist. Walk out, walk across the road so you're looking at the full elevation, and go through it.

1. The overall pitch

Roof pitch is the angle of the slope, measured from horizontal. The pitch of your roof decides which tile materials are compatible (see the material guide) and which repair options are realistic.

You don't need a precise number. A rough category is enough for a brief:

• Shallow (under 25°): the roof looks low and long from across the street. Typical of post-war housing, some bungalows, many modern estates.
• Medium (25°–40°): the most common UK pitch. A standard two-storey semi usually sits here.
• Steep (40°+): the roof looks tall from the front. Victorian terraces, gable-ended cottages, many listed buildings.

If the roof looks noticeably lower than the neighbours' — same style of house, same age — that can be a warning sign of previous structural movement. Note it down.

2. The covering material

Identify what's actually on the roof. This is the single most useful piece of information you can give a roofer before they visit, because it decides material costs, what they need in the van, and whether they're even the right person for the job.

• Natural slate: dark blue-grey to black, rectangular, overlapping in regular horizontal courses. Older slate fades to lighter grey. Reads as a uniform texture from the street.
• Concrete interlocking tile (Marley Modern, Redland 49): large tiles, individual tile outline visible from the street, wavy or straight edge profile. Often faded from the original colour to a patchy grey-brown.
• Clay plain tile: small individual tiles, dense pattern, usually red or orange-brown. Very common in southern England.
• Clay or concrete pantile: obvious S-shape curves across the roof. Common in East Anglia, Lincolnshire, East Yorkshire, and Scottish east coast.
• Cement-fibre sheet (usually a garage or outbuilding): large grey corrugated panels. Older panels may contain asbestos — do not touch or break them. Treat as asbestos until a specialist says otherwise.
• Felt (on a flat roof extension): black, slightly shiny when new, dull and stony when old. Visible seams running across the roof surface.
• EPDM rubber (flat): matt black, smooth, no visible seams on small roofs.
• GRP fibreglass (flat): light grey or off-white, glossy, sometimes with a slight orange-peel texture.

3. Age signals

Several things give a rough age of the covering without you needing to know exactly when it went on.

• Moss and lichen growth.Moss thrives on the north-facing slope of a roof and on rough surfaces. Some moss is normal. Dense green patches covering more than about 20 percent of the north slope are a sign of a roof that's at least 15–20 years old, holding moisture, and at the stage where the growth itself is starting to lift tile edges and block valleys.
• Colour fading and patchiness.Concrete tiles in particular fade heavily after 20 years. If the original colour was red and it's now mottled grey-brown, you're looking at a roof that's well past its prime.
• A visible dip in the ridge line.Stand back far enough to see the top line of the roof end-to-end. It should be straight. If it sags — even slightly — that's a structural signal, not a covering signal, and it needs a surveyor's eye rather than just a roofer.
• A wavy surface instead of flat planes. Each slope should be a clean flat plane. If the surface undulates, the battens or rafters underneath have deflected — likely age-related on older properties.

4. Missing or slipped tiles

Scan the roof slopes for anything that looks out of place. Missing tiles leave a visible dark gap (the underlay showing through). Slipped tiles are usually still present but at the wrong angle — you can see one sitting lower than its neighbours or protruding above the line.

Note the position carefully: which slope, how many courses down from the ridge, how close to a valley or chimney. Photograph it with your phone zoomed in. This single piece of information can turn a "need to come and look" into "I can quote from your photos, £380, next Thursday".

A single missing tile is a morning's work for a competent roofer. Five or more, spread across the roof, is a sign the nail-fixings are perishing and the roof is entering the end-of-life phase.

5. The ridge line and hip lines

The ridge is the top horizontal edge where two slopes meet. The hips are the angled edges on a hipped roof. Both are finished with ridge tiles, and those ridge tiles are held down with either mortar (old-style) or mechanical clips (modern).

• Gaps between ridge tilesare a sign the mortar has failed, which is a standard age-related issue. It's not an emergency but it's a leak path in high winds, and it's cheap to fix if you catch it early (£250–£500 re-bedding in most cases).
• Crumbling mortar falling into the gutteris the same thing at a later stage. If you're seeing little cement chunks in the gutter after a windy week, the ridge needs re-bedding.
• A visibly displaced or lifted ridge tile after a storm is usually what brings people to a roofer in the first place. Get it sorted in the next week because wind-driven rain gets in the gap beneath.

6. The chimney

If you have a chimney, it's the most common leak point in the whole roof and worth a specific look.

• The flashing is the metal (usually lead) sheet that seals where the chimney meets the roof. Look for visible cracks, peeling, lifted edges, or missing sections. Good lead flashing reads as a clean dark grey strip around the chimney base. Bad flashing looks crumpled, uneven, or has visible daylight through the join.
• The mortar jointson the brick stack itself. Crumbling mortar ("blown pointing") is a common issue on Victorian chimneys and is a leak source in its own right.
• The pot and cowlat the top. Broken or missing pots, cracked caps, birds' nests visible — all worth noting.
• A leaning chimney. If the stack is visibly tilting, stop reading and phone a roofer today. Leaning chimneys fall, and they fall in one piece through whatever is below them.

7. Valleys and junctions

A valley is the internal angle where two roof slopes meet and water drains down the gutter. It's one of the highest-stress points on any roof because all the water from two slopes concentrates into a narrow channel.

• Moss or debris visible in the valleymeans water isn't running freely. Leaves in autumn, moss in winter, the valley chokes and water backs up under the tiles either side. This is a common cause of "mystery" upstairs leaks.
• Mortar-bedded valleys (traditional on older roofs) crack with age. You can sometimes see hairline cracks from the ground on a steep valley if the light is right.
• Lead valleys work well when in good condition. Stains running down from a valley onto the slope below can indicate a split.

8. Fascia, soffit, and gutter line

The last detail is the eaves — where the roof meets the top of the wall. This is where the fascia board (vertical), soffit (horizontal, underneath), and gutters all sit.

• Rotten timber fasciashows as peeling paint, visible dark patches, sometimes a soft or crumbling edge. Common on older painted-timber fascias that haven't been maintained. Usually visible from street level with binoculars.
• Sagging or separated gutters come from clogged downpipes, fascia rot (so the brackets have nothing to hold onto), or age-related bracket failure. A gutter with a visible dip, or water staining the wall below it, needs attention.
• Birds nesting in the soffit void. Missing ventilation cells or gaps in the soffit allow sparrows and starlings to get in. Once inside they create a long-term problem for ventilation, insulation, and sometimes the electrics.
• Moss in the gutter is a maintenance issue that turns into a leak if ignored — a blocked gutter overflows onto the fascia and the water runs down the wall behind the top course of brick.

The photo set you want to send

Whichever roofer you end up phoning, their life is easier if you send photos first. Here's the set:

1. One wide shot of the full elevation from across the road. Just the house, the whole house, level and straight.
2. One wide shot of the rear elevation from as far back in the garden as you can get.
3. One close-up zoom on any specific problem you've spotted — the slipped tile, the gap in the ridge, the cracked flashing. Phone zoom is fine.
4. One close-up of the chimney stack from the ground, zoomed.
5. One side-on shot that shows the gutter line along the eaves.
6. Optional: a loft photo of the underside of the roof, if you can take one safely (stepping on joists only, torch pointing up) — daylight visible through the underlay, water staining on battens, sagging felt, anything unusual.

Send them with a three-line brief: what you're seeing, when it started, and what your question is. A roofer looking at that package can often give you a ballpark quote and a plan without a site visit. That's the fast path to three comparable quotes.

When you need to act, and when you can wait

Act now (this week): active leak inside, visibly leaning chimney, multiple slipped tiles after a storm, daylight through the underlay in the loft, cracked flashing visible around a chimney.

Act soon (this month):single slipped tile, mortar chunks in the gutter, moss building in valleys, damp patch upstairs that isn't getting worse, early signs of fascia rot.

Watch and plan: colour fading on concrete tiles, general age signs but no active problem, a roof approaching its service life without any specific failure. You have time to budget and take three proper quotes — see the costs guide.

Stop reading and phone someone:water coming through a ceiling right now, a chimney that's tilting, tile fragments on the pavement after high wind. The emergency triage piece walks you through the first thirty minutes if that's where you are.

What to do with all of this

If you've read this and you're ready to get quotes, the quote formhas a section for photos and a section for your notes. The more of the above you've filled in, the better the quotes that come back. The roofers we pass it to are checked against Companies House — the hiring checklist covers the rest of the due diligence before you commit.