If you have a roof over 20 years old, can see daylight when in the loft, or have a continual plague of water leaks, it’s time to replace your roof. But how much does it cost?
Well, the average cost of a new roof replacement for a typical 3 bedroom home in the UK lies between £5,000 and £7,000. And it’ll take from 3 to 4 days. It’ll cost about £2,000 to replace fascia and soffits, and more if you choose roof slates rather than concrete tiles. Furthermore, if the roof timbers need attention expect to pay out yet again.
This job is probably one of the most expensive single maintenance jobs you can do on your property. But it’s also one of the most useful. If you decide on a new roof, you’ll probably fix most, if not all the damp problems in your home.
How Much Does A New Roof Cost?*
You might think that a roofer just lays slates or tiles. But, there are a variety of jobs that come under a roofer’s umbrella. The jobs range from
- Fitting lead flashing around a chimney.
- Repairing lead in a valley between two roofs.
- Installing a waterproof membrane under tiles.
- Fixing battens, as well as many types of roof coverings.
In the table below, we’ll consider the different sized houses, various roof coverings and the roof replacement estimate for each.
|House size||Roof material||Estimated cost|
|2 Bedroom Bungalow||Tile||£3,700 to £6,000|
|Slate||£4,000 to £6,000|
|3 Bedroom Terraced House||Tile||£4,500 to £7,000|
|Slate||£5,000 to £8,000|
|4 Bedroom Semi-Detached House||Tile||£5,000 to £7,500|
|Slate||£4.500 to £7,000|
|5 Bedroom Detached House||Tile||£5,500 to £9,000|
|Slate||£6,300 to £12,000|
* Remember, we compiled the data from different online resources when we estimate labour and materials costs. So, use them as a guideline only, and don’t forget the figures don’t include VAT. Additionally, labour prices for roofers to retile a roof vary throughout the UK. Prices asked in London, and the Southeast might be as much as 20% greater than elsewhere in the country.
Usually, you can only get an accurate quotation for the cost of replacing a roof, from a reputable and experienced roofer, after a site visit. Only then can he incorporate the variables such as access, roof size, and other potential problems. Never accept a new roof cost estimate over the phone.
Re–roofing 2 Bedroom Bungalow
A typical 2 bedroom bungalow has a pitched roof area of about 75m2 depending on pitch angle. Usually, a few valleys or hips are incorporated into the roof design unless it is a gabled bungalow. Valleys need leadwork to waterproof the internal corner join. In contrast, hips need ridge tiles to cover the external corner join. And, of course, a ridge needs tiles to cover that join.
Some common roofing materials (labour not included):
- At £65/m2, Welsh slate calculates to around £4,875, based on the average roof area.
- Clay tiles at £125/m2 calculate to £9,375.
- Concrete tiles at £35/m2 (some of the cheapest roof tiles) calculate to £2,625.
- Shingles at £30/m2 calculate to £2,250.
3 Bedroom mid-terraced House Roof Replacement
Typically, a 3 bedroom mid-terraced house has a roof area of around 55m2 depending on pitch angle. Because it has adjoining properties on both sides, it won’t usually have valleys or hips to worry about. But, the new roof must join seamlessly with those belonging to the neighbours. Therefore, you must use a roof covering from a limited range that matches the existing.
Some common roofing materials (labour not included):
- Welsh slate at £65/m2, calculates to around £3,575.
- Clay tiles at £125/m2 calculate to £6,875.
- Concrete tiles at £35/m2 calculate to £1,925.
- Shingles at £30/m2 calculate to £1,650. These are tiles made from a fibreglass core covered in bitumen. There are generally three grades, and the choice depends on how much you want to pay and what you intend covering.
Replacing a Roof on 4 Bedroom semi–detached House
A 4 bedroom semi-detached house has a typical roof area of about 70m2, depending on pitch angle. It also joins onto one other property. Therefore, like the terraced house, the roof covering is limited to one that matches the existing.
Some common roofing materials (labour not included):
- Welsh slate at £65/m2, calculates to around £4,550.
- Clay tiles at £125/m2 calculate to £8,750.
- Concrete tiles at £35/m2 calculate to £ 2,450.
- Shingles at £30/m2 calculate to £ 2,100.
Re–roofing 5 Bedroom Detached House
A typical 5 bedroom detached house has an average roof area of around 100m2 depending on pitch angle. The property stands alone so you might be able to change to a different roof coverings style depending on local authority permission. The new roof might have hips and valleys. And, if so, needs leadwork or extra ridge tiles.
Some common roofing materials (labour not included):
- Welsh slate at £65/m2, calculates to around £6,500.
- Clay tiles at £125/m2 calculate to £ 12,500.
- Concrete tiles at £35/m2 calculate to £ 3,500.
- Shingles at £30/m2 calculate to £ 3,000.
Many factors vary the costs to re-roof a house. Some factors relate to materials, some to equipment and some to labour. Let’s consider those now.
Slate vs tile
Slates are smooth flat sheets of a type of rock called slate and lie next to the neighbouring slate. In contrast, tiles usually clip to their neighbour using a combination of interlocking grooves and projections. Therefore, tiles take less time to install because they don’t need nails as a fixing method.
Large slates and tiles need fewer to cover a square metre so take less time to install.
Height above ground
All roofing work needs scaffolding. But a house needs more scaffolding than a bungalow. Similarly, a large house needs more scaffolding than a small house. Scaffolding for a typical 3 bedroom house costs around £1,000 to £1,500 to hire. Therefore, hire costs vary depending on the size of the project.
It’s often impossible to tell if rafters need repair or replacement until the roof covering has been removed. Only then does the true scale of the project, and its cost reveal itself.
While you have roofers working at height, it’s often sensible for them to re-point the chimney if necessary. Re-pointing is an extra task that depends on how many chimneys you have and their condition. In extreme situations, they might have to rebuild the chimney entirely.
Replacing fascias and soffits
These are the wooden boards that run along the lower ends of the rafters, and prevent birds and insects from infiltrating your loft. The boards are exposed to the weather, so become rotten very easily. If you need your roof replaced, inspect the fascias and soffits and replace them with white uPVC replacements.
Rainwater gutters and downpipes.
Usually, your house has asbestos, cast iron, aluminium or plastic guttering on the roofline, depending on its age. None of these last forever, so it’s usual to replace with new plastic guttering as a matter of course.
Replacing a roof always generates waste. Depending on the type of project and the roof’s size, you need at least one large waste skip.
Although the UK Building Regulations aren’t retrospective, if you renovate more than 50% of the roof, you must ensure the insulation thickness is at least 270mm deep. So, buy more insulation to keep up to date.
Underneath the tiles or slates, we stretch a waterproof sheet, to prevent rain finding its way into the loft. The cost of replacing roof felt under tiles varies depending on the quality of the product. Even if it’s already fitted, it’s a good idea replacing the roof felt for new. Because, once the tiles go on, you can’t easily access it again.
There are many different types of house roof tiles and slates available in the UK. However, you might have to use types from a very specific local authority list. Local authorities can be strict when maintaining a property’s appearance. They insist that the roof stays ‘in-character’ with the others in the area. If you aren’t sure, contact your local authority and find out beforehand. If you go ahead and use a roof covering not approved for your area, the council insists that you remove it and replace at your own cost. Very expensive!
A new roof’s cost varies depending on size, thickness, and design of tiles or slate. Some, such as natural Welsh or Cornish slate, are individually split from slate blocks. Therefore, like every natural material, each one is unique. In comparison, tiles are identical because they’re made with moulds, and can be almost any style. Clay tiles, made with moulds, are then baked. In contrast, concrete tiles just cure.
Another criterion determining the type and amount of roof covering you choose is the roof’s pitch angle. You have to calculate how many roof tiles per m2 because of the different overlap as the roof pitch varies. And, some tile designs are better for steep pitches rather than shallow ones. It’s all down to making the roof weathertight.
Typical roof coverings include:
Welsh and Cornish Slate
Welsh and Cornish slate are both relatively expensive (around £65/m2), but of very good quality.
- Each slate is unique. Because the manufacturer splits natural slate, no two slates are the same. This feature gives a pleasing appearance.
- Slate is durable. It’s a natural stone, so it is unaffected by weather extremes and is fireproof.
- Slate’s long lifespan depends on the rock’s quality; most roofs made from man-made materials last about 25 years. However, good quality slate lasts at least 80 years.
- Low maintenance is a perk when using slate. Rock’s durability means that the slates don’t need repair and its low absorption of water means that there’s little chance of mould growth.
- Slate is high–quality roofing material. So, if you can afford to install real slate on your roof, your home increases in value and has more kerb appeal than those with cheaper roof coverings.
- Real slate is expensive in terms of material cost, and in the specialist labour required to install slates. However, to compensate for the higher cost, slates last much longer.
- Real slate is a heavy natural material. The slates are heavy for the roofer to carry onto the roof. And, need a strong roof structure to carry the weight. If you intend changing from lightweight roofing material to slate, first get a structural engineer’s advice. It would be best if you also got the local authority’s advice because a slate roof might not be in keeping with the other houses in your street.
Reconstituted slate, made from slate dust, fibre cement and resin is very cheap (around £28/m2). Generally, reconstituted slate is a cheaper alternative to natural slate. It contains up to 60% recycled material, so it’s more environmentally sustainable.
- Reconstituted slate is much cheaper than real slate. Therefore, it’s an affordable roofing material.
- The lower price is partly due to the use of around 60% recycled material.
- Reconstituted slate looks good as a roofing material if you want every piece to look the same.
- The moulded man-made slate has fixing points built into the structure.
- It’s thinner than real slate and lighter in weight.
- They are easier to cut to shape if required.
- Reconstituted slate doesn’t have the natural strength of real slate. Therefore, it’s less resistant to cracking.
- Each piece is brittle and easily broken.
- This type of slate has less durability than real slate and lasts for up to 60 years.
- It’s not a good idea for a roofer to walk on reconstituted slate.
- Susceptible to damage from pressure washers.
Clay tiles are good quality and very expensive (around £125/m2).
- Clay tiles mould to almost any shape. The material is then ‘fired’ like ceramic and pottery and is as waterproof as any other fired clay.
- Unlike slates, they’re made to whatever shape or size you need.
- Manufacturers mould various fixing methods (lugs and nail holes) into the tile structure.
- Clay tiles can perform with very shallow roof pitches, often as low as 15°.
- You can have clay tiles of whichever colour you prefer. Dyes go into the clay mix or added at the firing stage.
- Clay roof tiles are very heavy and might not be suitable for a weak or lightweight roof structure. Always consult a structural engineer before going ahead with this option.
- Clay tiles don’t always stand up well to high winds. They can work loose and fall off.
- Fragility is a concern as clay tiles are very brittle.
- Clay tiles need specialist installation as they aren’t easy to cut, and need the correct pattern to ensure a weathertight surface.
- Clay tiles are expensive compared to other tile material.
Concrete roof tiles
Concrete roof tiles, another cheap roof covering, costs around £15/m2. The material is very versatile and forms a variety of shapes and designs. Add dyes to make the concrete almost any colour.
- Concrete tiles need very little maintenance. The material is tough and is difficult to damage. Therefore, you probably won’t have to do much maintenance other than an occasional clean to remove moss and mould.
- These tiles last a long time. If properly made, and cleaned regularly, they can last for over 50 years.
- Like other concrete construction products, the material is fireproof.
- Use special dyes to turn concrete tiles to almost any colour. The dyes allow the householder to create beautiful designs on their roofs by incorporating different colours. Using textured moulds, they can resemble wood, slate and many other materials.
- Concrete tiles are very heavy and need strong roof supports to take the weight. Consult a structural engineer for advice on potential roof strengthening problems.
- Although concrete tiles are difficult to break, they will sustain damage if a load is applied in a certain way. Falling branches and heavy hailstones sometimes crack concrete roof tiles.
- Concrete tiles are not completely waterproof and can absorb a large amount of water leading to stains, moss, mould and mildew.
- These tiles are heavy. But, they aren’t entirely wind–resistant. High winds can dislodge the tiles and allow water ingress.
- Replacing roof tiles singly or in small groups can be difficult if they are of the interlocking type.
Shingles, made from bitumen covered fibreglass is another cheap material (from £15 to around £30/m2). But, they have a shorter lifespan than tile or slate. In the UK, we don’t often use this material for domestic buildings. Instead, we use them as a roofing material for sheds, garages, summerhouses and gazebos.
- Bitumen shingles are a cheaper roofing material than slate or cedar shingles.
- They are quick and very easy to install. However, cedar shingles might need a professional installer.
- Used in place of shed felt, they last longer and are thicker and more durable. Whereas shed felt lasts no more than 5 years, shingles last for at least 10 years.
- There is no need for cleaning or anti-fungal treatments; bitumen shingles won’t rot.
- They come in different colours and textures, so you have a large range to choose from.
- They are fire retardant and resistant to extreme weather temperatures.
- We can only use them on boarded roofs to accept fixing nails.
- The roof pitch must be 15° or more to prevent water from passing under the laps.
- They are lightweight so they might be susceptible to tearing by strong winds.
Thatch, made from straw or reeds, needs a specialist installation contractor. Typically, materials cost around £100/m2. Generally, thatch was a byproduct of the agriculture industry and is a traditional British roofing material, used for many centuries.
- Generally, thatched homes tend to be old and listed buildings. So, if you have a modern house with thatch, you can be sure it’s a novelty.
- Thatch is a very durable roofing material and can last for up to 60 years if properly installed. Water reed is the most durable, lasting from 50 to 60 years; Combed wheat reed lasts from 20 to 40 years; Long straw lasts for 15 to 25 years.
- Thatch is a naturally insulating material that maintains an even temperature all year round and saves money on the energy bills.
- It is a sustainable construction material that is grown and harvested when needed. Methods of harvesting are also environmentally friendly as well.
- Skilled thatchers can produce many different aesthetically pleasing shapes.
- Thatch is a lightweight material so won’t need specially prepared roofing supports.
- Thatching a roof is very labour intensive. Therefore, labour costs are very expensive. A typical large detached house with dormer windows and a chimney can have a re-roofing cost of around £30,000 to £40,000
- It’s essential to have the thatch professionally inspected annually for maintenance and insurance purposes.
- Thatch is a high maintenance material. It’s relatively simple for the ridge cap to become dislodged and need repair. Leaks can cause problems in many parts of the house.
- Safety precautions to prevent fire and pest infestation are essential. The house needs a lightning rod to prevent lightning strikes; Remove surrounding tree branches to prevent damage to the thatch and reduce the amount of moisture in the thatch by increasing sunlight. You also need a spark resistor for the chimney, and pest deterring treatments.
- There aren’t many professional thatchers around. So, you might have to wait for many months for a slot to become free in his schedule.
Types of Roofing
There are many different roof type. Older houses and expensive properties are more likely to have an unusual type of roof. In contrast, cheaper properties have simple, less labour intensive designs.
A gable roof is simple to design and easy to build. It is a simple design where two sloping roof planes meet at the ridge.
A hip roof usually has four sides, all of which slope towards the ridge. They work well in high wind areas.
This is a roof of French origin. It contains two slopes of different pitches on each roof plane. They provide extra room on the inside, and you’ll commonly find them in attic rooms, and barns.
Even though these are called ‘flat roofs’, they aren’t flat! Instead, they have a very slight pitch, just enough to facilitate rainwater runoff.
A shed roof is very similar to a flat roof but has a more gradient. It is common in one storey extensions.
How The Job is Carried Out
Timber roof systems usually consist of pairs of common rafters (rafters with a simple ‘one angle’ cut on each end). If you incorporate hips or valleys into the roof, you need rafters with compound cuts (rafters with two angled cuts on each end).
There are two types of roof construction. A ‘cut’ roof and a ‘truss’ roof.
- A ‘cut roof’ (or ‘cut rafter roof’) consists of various length rafters and joists cut on-site to build up a framework on which you fix the roof covering. Usually, a ‘cut roof’ uses over-engineered timbers (they have larger cross–sectional dimensions than needed to cope with the loads).
- A ‘truss roof’ is made in a workshop or factory to structural design drawings. Each pair of rafters is fixed together with a built–in joist to produce an ‘A’ frame. Each component of the ‘A’ frame uses timber with cross-sectional dimensions designed to withstand the applied loads plus a safety factor.
Let’s move on, and see how we construct each roof. We won’t go into too much detail, because only a roofing carpenter has the skills and experience to build a roof structure.
Construction of a cut rafter roof
- The roofer fixes a wall plate at the top of the wall. The wall plate is a length of timber fixed on the top of the wall around its perimeter. The wall plate provides somewhere to support and fix the rafters and joists.
- Cut the rafters to the appropriate length with angled ‘birdsmouth cuts’ so the rafter toe sits on the wall plate without pushing outwards. In the UK, rafters are 400mm, 450mm or 600mm apart. However, extra rafters might infill if the roof’s dimensions and aren’t exact multiples of these distances.
- The ridge board is a board placed at ridge level between each pair of rafters. It gives somewhere to fix the rafters and helps keep the rafters at the correct distance apart.
- The joists are timbers placed horizontally across the building and supported on opposite sides. Each joist is fixed to the wall plate and also fixed to the lower end of each rafter. So, they prevent the rafters from spreading.
- After erecting all the rafters, it’s time to attach the purlins. A purlin is a length of timber of large cross–section, fixed horizontally to the underside of, and joining each rafter. Therefore, each roof plane has a purlin running its complete length. A purlin keeps the rafters at the correct distance apart and supports the weight of the roof. Additionally, short vertical timber lengths fixed between the joists and the purlin provide support.
- Collar beams (or collar ties) are timbers fixed horizontally between opposite rafters, usually about halfway or threequarters of the way up the roof height. Once again, collar beams might have vertical timbers fixed between the beam and the joists for extra support.
Construction of a truss roof
Each building has a specifically designed truss roof. Usually, made from timber but occasionally uses steel, especially if it’s a large roof.
Each truss is structurally sound on its own. They stand on the wall plate at specified distances apart, as shown on the construction drawing. Then, held in place by diagonal boards fixed across the underside of two or three ‘A’ frame rafters.
The timber used has the minimum cross–sectional dimensions needed to support the load. There is no ridge board, but a board horizontally connects the underside of each truss’s apex.
Trusses don’t need extra structural supports such as purlins or collar beams because each truss can support itself and the load it’s designed for.
Depending on the roof’s design, the rafters or trusses might be covered in boards (or not), followed by a waterproof membrane to cover the entire roof surface.
Next, nail tiling battens horizontally to the rafters (or boards) at a vertical distance apart to suit the type of tile or slate you intend using.
Fix each slate or tile starting at the eaves and finish at the ridge. Each course has an appropriate overlap, depending on the roof’s pitch and the type of covering. The idea is to prevent rainwater from blowing under the tile.
The UK Building Regulations specify the size of timbers and the distances apart for various pitches and spans. And they must be adhered to.
Do not attempt to replace a roof as a DIY project. You must always:
- Use a structural engineer to design the roof.
- Hire a professional carpenter with roofing experience. He will cut and assemble the various roof timbers as directed by the structural engineer’s drawings.
- Finally, use a professional roofer experienced in using the specified roof covering.
Signs That Your Roof Requires Replacement
You must not replace the roof yourself. However, it’s acceptable to keep an eye on your property and notice anything out of the ordinary, that might indicate you need a new roof.
- Cracked or missing tiles and slates are a dead giveaway. Although a few damaged or missing tiles here and there won’t mean you need a new roof, you must get them replaced straight away. If you have large patches of damaged tiles, call in a professional to advise whether the entire roof covering needs replacing.
- Water damage to the bedroom ceilings indicates that rain is getting in somewhere. Usually, this indicates damaged tiles or lead flashing. Get it fixed.
- Go into your loft and search for light shining through cracks or holes. You might be able to have them repaired. But if it’s a major task, consider having the tiles replaced.
- The ridge should be a horizontal straight line. If the ridge sags, then there is something seriously wrong with the roof timbers. You need the roof covering removed, followed by repair or replacement of roof timbers.
- To have a completely waterproof roof relies on the tiles and waterproof membrane working together. Over time the membrane starts to disintegrate or tear. Therefore, you need a replacement. Remove all the tiles and replace the membrane before returning the tiles.
- Look at the ridge tiles along the top of the roof. If they are loose or the mortar crumbles, have the remainder of your roof inspected. Faulty ridge tiles allow water ingress, which damages the roof timbers, and the remainder of your house. If you are lucky and you’ve caught it early enough, you might only need a few ridge tiles replacing. Otherwise, it’s a big job.
If you have a damaged roof covering, you allow water and possibly wind to enter your home with disastrous results. Roof replacement costs might look daunting, to begin with. But, it’s a false economy to ignore the signs of a failing roof, as you pay for even more repairs in the long term. A new roof guarantees that you won’t have any weather coming indoors. You should always use the latest waterproofing products to help keep your home safe and secure. Also, a new roof helps keep indoors dry and warm. If you have repairs to more than 50% of the roof, you must by law, increase the loft insulation to at least 270mm thick. Thus reducing your energy bills.
Nothing looks worse than a neglected roof. It implies that the remainder of the house is in the same state, or worse. And, this indication is often true. The water coming into the house causes major problems throughout the property, such as damp, electrical problems, plaster falling off the walls and the entire property needing decoration.
UK Planning Permission & Building Regulation
You don’t usually need planning permission if you want to re-roof your house. This work comes under ‘permitted development’. However, you must comply with certain restrictions before you can go ahead.
- No alteration must raise the roof by more than 150mm.
- No alteration must be higher than the highest part of the roof.
- The side facing windows must be obscure glass, and any opening must be more than 1.7m above the floor.
Additionally, check whether you live in an area with restrictions on the roof covering types or colour.
In contrast, you must comply with the Building Regulations and other restrictions.
Before any work starts, check that no protected species live in your loft. Bats like lofts to roost in and you need a survey to decide if there are indications of bats. And, if they are present, you need a licence before starting work.
The Building Regulations are there to ensure your roof is structurally sound and strong enough to support the loads placed upon it. You also have to ensure the thermal insulation depth meets the required standard.
Your local Building Control office must always be informed when replacing a roof so that they can monitor the work from start to completion.
Roof Replacement FAQ
Should I replace my own roof?
No! While it’s okay to do some jobs around the house as a DIY project, re–roofing your home isn’t one of them. Many things might go wrong, and you need specialist knowledge to put things right. Not only that, but Building Control monitors the job and requires proof that you are an experienced roofing professional.
Does a new roof add value to your home?
A new roof on your property can add between 15% and 40% of your property’s value. This amount is far more than the cost to have the work professionally done.
How often do you replace a roof on the house?
A typical roof’s lifespan depends on the roof covering type, whether you have regularly maintained the roof and replaced any broken or leaking tiles. And, whether you live in a particularly exposed area.
However, on average, a well–tiled roof can expect to last for up to 60 years. While a roof covered in good quality real slate can last for over 100 years.
Can you put a new roof on top of an old roof?
Generally, this isn’t a good idea. If the roof covering needs replacing, you must remove it to check the roof timbers and replace the waterproof membrane before replacing the tiles or slates. However, you can re-use as many of the slates or tiles as you can. Moreover, it is actively encouraged by local authorities, so that the new roof blends in with the surroundings.
Should I replace the roof before selling my house?
Not necessarily. However, it is worth hiring a qualified professional to give you a roof survey before putting the house on the market. The survey identifies any potential problems that might hold up the sale. And, if there are problems, you can get repairs done or reduce the selling price accordingly.
What is the cheapest roofing material?
Generally, asphalt shingles are the cheapest. But, local authorities do not usually approve these for a domestic property. Usually, they restrict shingles to structures such as sheds, garages, agricultural buildings, and gazebos.
For a domestic building, the cheapest roof coverings are reconstituted slate at around £28/m2 and concrete roof tiles at between £15 to £25/m2.
What time of year is best to replace a roof?
The most popular time of year to have your roof replaced is in the late summer to early autumn before the cold, wet weather sets in. It’s because most people notice problems during the previous winter or spring, which then leaves time during the early summer to organise the contractor and any permissions that you need. However, please don’t leave it so late in the year that the bad weather starts before you complete the job.
Get Local Roofing Quotes
The cost of a new roof replacement can look very daunting. But, just because the job costs a few thousand pounds to sort out, doesn’t mean you can put it off. And, definitely doesn’t mean that you can do the work as a DIY project.
Complete the form on this page, and you will get 3 or 4 quotes from qualified and experienced roofing contractors who can make your roof as good as new.