Haverhill Roofers provides roof repairs for homeowners in Sawston, using the right materials for the job and giving you an honest picture of the options before any work begins.
Call any time. Calls are answered day and night and passed straight to our roofers.
When a roof repair is needed, one of the first practical questions is what material to use. In many cases the answer is simply to match what is already there, but sometimes a repair is an opportunity to use something better-suited or longer-lasting than the original. This page works through the main materials used in pitched and flat roof repairs, with honest notes on what each one does well and where it falls short.
Concrete interlocking tiles are the most widely used covering on post-war pitched roofs. They are available in a broad range of profiles and colours, they are manufactured to consistent dimensions, and they are relatively straightforward to source and replace individually. For a repair job, matching the profile is usually possible even on older roofs, though the colour of a new tile against weathered originals will always show for the first few years until the new ones weather in.
The main drawback of concrete tiles is weight. A full concrete tile roof is considerably heavier than a natural slate or plain clay tile roof, and the roof structure needs to be capable of carrying that load. On extensions or outbuildings with lighter roof structures this can be a consideration. Concrete tiles also develop a surface coating that wears off over time, which is when moss and algae take hold most readily.
Natural slate is a genuinely long-lived roofing material. Welsh slate in particular has been used on British roofs for well over a century and performs extremely well when correctly installed. Matching existing slate for a repair is achievable but requires care - different quarries produce slate of different thicknesses, colour tones and grain, so sourcing a close match takes more effort than buying a box of concrete tiles.
Slate is fixed by nails through a pre-drilled hole into the batten. When those nails corrode (which typically happens after several decades), slates slip without warning. The repair is to nail them back with new fixings or, on slates that have cracked, to replace them entirely using a tool called a slate ripper to remove the old nail and broken piece. Slate is less straightforward to repair than interlocking tiles because adjacent slates have to be temporarily lifted to access the fixings - but done carefully the repair is invisible and sound.
Reclaimed slate is worth considering for repair work on older properties. It has already weathered to a similar appearance to the existing roof and tends to be a closer visual match. The trade-off is that reclaimed slate cannot be guaranteed to be free of hidden cracks, so sourcing from a reputable yard and checking each piece before fixing matters.
Plain clay peg tiles are found on older and period properties. They are smaller than concrete interlocking tiles and are hung on the batten by nibs at the top edge rather than nailed through. Each tile overlaps its neighbours by around two-thirds of its length, giving a double or triple layer of coverage at every point. This construction is very good at shedding water but requires more tiles per square metre than an interlocking profile.
Sourcing matching plain clay tiles for a repair can be difficult - manufacturers still produce them but the range of colours and profiles has narrowed over the decades, and older handmade tiles have subtle variations in size and surface texture that modern machine-made tiles do not always replicate well. Reclaimed tiles are often the better match here too.
Lead is the standard material for flashings at chimneys, dormers, valleys and abutments, and for a good reason: it is malleable, durable, and when correctly dressed and pointed it remains watertight for a very long time. Code 4 lead (approximately 1.8mm thick) is the minimum for most domestic flashing applications; Code 5 is used on wider soakers and back gutters behind chimney stacks where more durability is needed.
The alternative to lead is a pre-formed aluminium or zinc flashing strip with a self-adhesive butyl backing. These are quicker to fit and cheaper in material cost, and on a small repair in a sheltered position they can perform adequately. The honest caveat is that the adhesive bond to brickwork can fail over time, particularly where the surface is uneven or slightly damp when the strip is applied. For a chimney or a wide valley that will be in place for decades, lead remains the better choice.
Traditional mineral-surfaced felt (torch-on or cold-applied) is still the most common material on domestic flat roofs - on extensions, bay windows and garage roofs. It is cost-effective and straightforward to repair or patch, but a felt roof has a finite life and repeated patching of an old, brittle felt surface gives diminishing returns. Once the felt has reached the end of its serviceable life, a full re-cover is the sensible answer rather than further repair.
EPDM rubber is an alternative worth considering when a flat roof section is being fully replaced. It is a single-piece membrane with very few joints, and fewer joints means fewer places for water to enter. It handles temperature extremes well and does not become brittle in the same way felt can. The upfront cost is higher than standard felt, but over the life of the roof the difference often balances out. It is not a patch material - it works best when the entire roof section is stripped back to the deck and the rubber laid on a clean, sound substrate.
The mortar used to bed ridge and hip tiles needs to be the right mix - too strong and it will crack as the roof moves with temperature changes; too weak and it crumbles out within a few years. A mortar mix that is too cement-rich is one of the most common causes of failed ridgelines on roofs that were re-ridged in the last couple of decades. Dry-fix ridge systems, which clip the ridge tiles in place mechanically without mortar, are now widely used on new roofs and re-roofing work. They are worth considering on a ridge repair because they eliminate the mortar joint entirely and are not affected by thermal movement in the same way.
For most repairs, the priority is matching what you have as closely as possible - in profile, colour, thickness and fixing method. On most properties, the existing roof covering will tell you most of what you need to know about what materials to specify for the repair. A roofer who looks at the existing roof carefully before ordering materials will produce a better-looking and longer-lasting result than one who reaches for whatever is nearest to hand.
Before any repair work is carried out, it is worth asking the roofer what material they intend to use for each part of the job and why. If lead flashing is being replaced, ask whether they are using Code 4 or Code 5. If tiles are being replaced, ask how they have sourced the match. These are straightforward questions and any competent roofer will answer them directly. Call Haverhill Roofers to arrange an inspection and honest quote for your roof repair in Sawston.
No obligation · We'll call you to arrange a free visit
Call any time. Calls are answered day and night and passed straight to our roofers.
