* All figures are supplied as a rough guide, and will vary depending upon area.

It’s very common to find roofing defects flagged up in Home Buyer reports and surveys, which have a distinct capability to evoke fear. Even uncomplicated repair works that involve working at height can cause bouts of financial vertigo, brought about largely by the substantial sums to pay for scaffold hire.

The requirement for total re-roofing is relatively uncommon. There are, nevertheless, possibly severe issues that routinely appear in studies, many of which need urgent moves to prevent leakage triggering problems to the building structure. Here, we describe exactly what to look out for, the repair works required, and the prospective expenses * included.

Defective Signs For Ridge Tiles, Hip Tiles and Verges

Recognition

leaking chimney pointingIf 10 or more tiles per slope are slipped or missing, the roofing is most likely to be nearing completion of its beneficial life and will require stripping and re-covering. With slate roofing systems, look for comparable numbers of loose slates that have actually been refixed with small metal ‘tingles’. In the loft, there might be smells and localised staining from water ingress.

If there are just a couple of slipped or missing tiles or slates, they can generally be refixed or changed fairly quickly. On shallow pitched roofings (common on 1970s properties), the underfelt can begin to droop, diverting rainwater down wall cavities. This might mean the lower layers of underfelt require to be stripped, replaced and rebattened.

 

A lot of roofs developed post-1950s also have a layer of underlay (‘ sarking felt’) supplying a secondary defence. Any wind-blown rain that permeates under the tiles need to be safely funnelled down to the seamless gutters.

Handmade clay tiles or stone slates can last 250 years or more compared to around 70 or less for some types of concrete tile.

Old tiles and slates can absorb water which then freezes and broadens. White powdery salts under the tiles can indicate disintegration and the projecting nibs at the top of each tile can break. In older slate roofings, the undersides of slates can be looked for indications of softening and flaking.

With roof spread, the ceiling joists typically act as collars restraining the rafters from pushing the walls outwards, so brand-new collars might have to be installed or tie rods inserted through the upper walls.

Deteriorated mortar joints require repointing = ₤ 28 for one tile, plus ₤ 10 per extra tile (include ₤ 10 if a brand-new hip iron is required).

Ridge/hip tiles which have come loose can be rebedded with an appropriately stiff mortar mix = ₤ 36 per tile, plus ₤ 19 for each extra tile.

Verges have the tendency to need localised pointing up with mortar = ₤ 32 per tile and ₤ 13 thereafter.

Another location to see is Victorian slated hipped roofs to bay windows which might have hip roll joints in lead or zinc.

Remedial Work Required

Labour and Materials **.

Strip roofing system of tiles/slates, battens and felt ₤ 18/m ²

. Refelt, batten and re-tile/slate stripped roofing system utilizing new tiles/slates:.

Potential Costs.

Nevertheless, because each slate is nailed to a batten, and slate sizes vary, they are more hard to raise out and change. Slipped slates can be refixed using copper or aluminium alloy nails. Or, if simply one or 2 are loose, then they can be protected utilizing little folded metal clips referred to as ‘tingles’.

Severely Damaged RoofSlates or Tiles Nearing completion of Their Life.

Ramifications.

Restorative Work.

On the other hand, in more extreme cases a structural engineer may have to be sought advice from and remedial structural work carried out. These causes include:.

Tiles can be prone to localised problems such as broken nibs. Even long-lasting plain clay tiles can ultimately begin to deteriorate and crack throughout the middle or ‘spall’ in layers. It’s relatively easy to change tiles because, unlike slates, they’re generally just nailed every fourth or 5th course.

The roof needs to be removed down to the rafters, brand-new breathable underlay set up, rebattened and lastly re-covered. With natural slate or clay tiles, it is frequently possible to restore and reuse a minimum of 50 per cent of the originals (lowering the cost of repair).

Minor settlement is not generally an issue; it’s relatively common beside gable ends and party walls where the rafters have actually settled more than adjoining masonry. If the structure is satisfying and there’s no leak, a reasonable quantity of historic settlement can be acceptable.

Gaps in between adjacent tiles/slates near gable ends or party walls can also develop where the roofing system slopes have settled more than the walls. Spaces of as much as 10mm either side of each tile are not normally substantial, as the lapped tiles below cover the space.

Raise the two tiles above it with wooden wedges.

Use a bricklayer’s trowel to raise the damaged tile off the batten.

Carefully move it out.

Ease a replacement tile in to its location.

Hook the nib over the batten.

Slate is a very durable natural product, however old repairing nails are prone to rust. Old slates can split across their width and middle, and even begin to delaminate (flake) in layers, too.

The durability of a roofing covering depends on the quality and age of the product, and the degree of direct exposure. The lifespan of traditional roofing coverings is typically exceptional to later on produced materials.

Repair is a fairly straightforward job:

Rotten timbers can be eliminated and new woods spliced together with (or bolted with metal plates). The source of leak need to be repaired and ventilation improved to distribute wetness.

However, older roofs were usually constructed with no underlay, and instead relied on an excellent flow of air aerating the loft to waft away any resulting damp.

The requirement for total re-covering is uncommon, however is a significant endeavor. Surveyors can in some cases be guilty of erring on the side of caution, so get a second viewpoint before major works. The urgency of this job will likewise depend upon the degree of the degeneration.

While fairly small defects, they’re fairly typical. If left untreated, the ingress of wet might decay roofing system timbers. Storms might also dislodge loose ridge tiles with the prospective threat of injury, too.

Overloading

— ‘dishing’ may be the outcome of previous recladding with heavier modern-day concrete roofing system tiles/slates without very first ensuring to strengthen the roof woods.

Weak roofing system lumbers

— rafters might have been undersized or spaced too far apart when the home was originally built. Or, they might have been cut (eg. for the botched installation of a rooflight) without the rafters being strengthened.

Roof spread

— the rafters have actually pushed outwards causing the top of the wall to bulge, which implies that the rafters might sink and trigger the roofing system to dip in the middle.

Rotten or beetle-infested lumbers

— this is usually due to long-term leak and poor ventilation.
Restorative Work.

Expenses of Complete Roofing system Re-covering.

It deserves keeping in mind that some roofers might be lured to use inferior, more affordable products when recladding older roofs. Like-for-like repairs are more suitable on natural clay and slate roofs.

Synthetic slate.

Slipped and Missing Slates and Tiles.

Remedial Work and Costs.

Changing a busted tile/slate = about ₤ 26 with ₤ 9 for each additional tile/slate.

Refixing an existing tile/slate = around ₤ 60 for one to 5 tiles next to one another, plus hire of access equipment.

Keep in mind that little tasks like this are most likely to draw in an added ‘hassle-factor’ price premium.

Implications.

Plain clay tiles.

Interlocking concrete tiles.

spaces and loose mortar at the joints between ridge tiles (which run along the top of the roof), hip tiles that cap the ‘corners’ on hipped roofing systems, or to verges of gables or lean-to roofing slopes

slipped ridge and/or hip tiles

missing out on hip irons (used to secure the tile at the bottom of the hip).

leaks and damp within the loft and to the upper roofing lumbers.

Implications.

To eliminate a broken tile:.

Restorative Work.

Recognition.

The odd dislodged or missing tile, is typically brought on by storm issue, or individuals strolling on the roof for TELEVISION aerial/satellite meal setup. A missing out on tile/slate is not usually an important problem, however repair should not be left for too long, particularly on roofing systems clad with bigger interlocking tiles (with less overlap), and on older roofing systems with torn, sagging or non-existent underlay.

If drooping is due to settlement to supporting internal walls below, then the walls need to be stabilised.

On 20th-century homes, asbestos-fibre synthetic slates and tiles are relatively rare, but most likely to sustain added expenses for removing and disposal.

Overloaded or weakened roofing systems can be repaired by installing added purlins and struts to improve assistance. This is fairly simple woodworking and should not be too expensive, providing that access is reasonable.

Natural slate.

Identification.

It’s not uncommon to identify small gaps where one or two tiles or slates have actually slipped or cracked. Rain ingress is just likely to be a problem where numerous adjoining tiles/slates are missing out on (thanks to the courses of lapped tiles/slates below).

 

Roofs on terraced houses can also suffer leaks where they satisfy at party walls. This has the tendency to be worse where each house has a different type of roofing system covering. In this case, localised stripping will be required with the arrangement of sheets of lead (soakers) under the joints, or new flashings at parapets.

These sorts of problems are a typical reason for leaks in older properties or extensions of poor-quality construction. In time, ingress of damp may have triggered adjoining woods to rot, and immediate repair work is generally required to prevent wear and tear.

₤ 44/m ².

The old lining is stripped back.

The lumber base is inspected to see if it remains in sound condition.

The old lining can then be replaced with new strips of code 4-thickness lead reversed and raised up at the edges (possibly laid in a number of lengths overlapped by a minimum 150mm).

A thin layer of fibrous product is inserted between the lead and the valley board (such as breathable membrane roof felt– however not mineral felt).

The lead is finally fixed in location with copper nails hidden under the overlaps.

Typical labour expenses will have to do with ₤ 250, with materials (lead sheet and a few tiles/slates) costing around ₤ 200– plus the hire of the access/scaffold tower.

Splitting can establish where roofing system slopes abut dormers, parapet walls and subsidiary roofs, or around objects such as chimney stacks and internal soil pipelines that are predicting through the roof. The resulting leakages and damp spots can be seen in lofts, ceilings, walls and chimney stacks.

Defective Flashing.

With older roofings, changing standard leadwork with matching brand-new products is advisable. Lead is a more expensive product, it’s worth keeping in mind that labour and access account for the bulk of the task cost. To change a malfunctioning lead or zinc valley on a normal Victorian slate or tiled roof:.

Changing Valleys.

₤ 151/m ².

Identification.

Such problems are not too difficult to repair, although replacing any decayed lumbers will include to the complexity and expense.

Valleys are the junctions between 2 adjacent roof slopes which permit rainwater to go to the guttering. Valleys made with preformed tiles are fairly robust and any malfunctioning tiles can be changed. Traditional open valleys have actually exposed linings which can, however, deteriorate over time. On roofing systems outfitted with big interlocking tiles, it’s likewise common for the mortar upstands either side to crack and come loose. They might just require pointing up. Alternatively, valleys can be relined utilizing preformed valley trays of glass-reinforced polyester.

₤ 106/m ². New ridge/hip tilesFrom ₤ 70/m ²

. Verges/undercloak pointedFrom ₤ 10/m ². Double eaves courses

pointedFrom ₤ 14/m ². ** Approximate cost including BARREL. Replaced slate roofing on a stone cottage in Yorkshire. The roof and its timbers

had actually to be changed in this stone cottage in Yorkshire.

Remedial Work.

Defective flashings must be replaced with new leadwork. Relatively pricey, the expense can be reduced by recycling the valuable old lead.

Lead flashings are very long lasting however can sometimes come loose. More rarely, old lead or zinc flashings may have split or corroded. Mortar fillets are a cheap alternative to lead and are particularly susceptible to cracking. Short-life tape repairs may even have been applied, or flashings painted to momentarily seal leaks.

Implications.

Butterfly Roofs.

The cost of scaffolding and access equipment hire needs to be included to the approximate rates for any of the jobs laid out in this piece.

Scaffolding per primary elevation/roof slope, including erecting and dismantling = from ₤ 450 for four weeks.

Mobile scaffold towers up to 6.2 m high for little Do It Yourself repair works = ₤ 200 each week.

Roofing system ladders for upper sloping roofings = ₤ 70 per week.

It is necessary to keep in mind that the Work at Height Regulations restrict making use of ladders to light, low-risk work just– which dismisses most roof repairs on two storey properties or higher. This can make little jobs relatively costly.

Scaffold Employ and Expenses.

Numerous Georgian and early Victorian townhouses have concealed ‘butterfly roofing systems’ with a main valley, or rain gutters concealed behind a front parapet wall. Being out of sight, they are vulnerable to neglect, obstruction and leakage.This frequently leads to substantial cost as they typically need relining in brand-new leadwork, with rotten assistance timbers changed. Parapet walls above the main elevations can be prone to collapse and ought to be tied to party walls and the roofing structure behind.

Now that you have read about the various types of roofing repair works there’s more to read about loose tile repairs here.