Flat Roof Cost
A roof is one of the most important parts of your home. Not only can a roof protect your home from the elements, but it can also keep your home warm and safe. Although flat roofs are commonly used on commercial buildings rather than on residential properties, they have become more popular as the roofing choice for homes. Flat roofs can also be installed on other buildings such as garages or extensions, as they have a variety of uses.
If you are thinking of installing a flat roof, then there are a few things to consider. These include deciding on what roofing material to choose, installation costs and weighing the pros and cons of installing a flat roof. This guide will give you a full breakdown on everything you need to know about installing a flat roof.
How much does it cost to install a flat roof?
There are many factors that can impact the total cost of a flat roof installation; however, a new flat roof installation generally costs between £1200 to £7000. Not only can a flat roof be installed on a property, but it can also be used as a roofing option for a porch, garage, dormer and most home extensions.
Here is a breakdown of the average costs to install a new flat roof on each of the following types of buildings:
|
TYPE OF BUILDING |
AVERAGE COST |
|
Porch |
£300 to £600 |
|
Dormer |
£700 to £1500 |
|
Double Garage |
£1200 to £2000 |
|
Extension Roof |
£500 to £3000 |
|
Flat Roof |
£1500 to £5000 |
Labour Costs and Timescales
When installing any kind of roof, it is highly advised to hire a professional roofer to install it for you. A roof should be installed using the correct safety measures and should be fitted accurately so that you roof is able to stand the test of time.
One of the main costs when installing a flat roof is labour costs. Roofers will typically charge between £25 to £50 per hour which roughly costs £200 to £500 per day depending on the tradesperson you hire. This charge may increase if 2 people are needed to fit the new roof as you will need to pay for a second set of hands. Most tradespeople will include labour fees in the total cost, but it is advised to double check the quote to make sure you are paying the right amount in labour costs.
Most flat roofs and extension roofs take 2 to 3 days to install depending on the size of the roof. Flat roofs installed on both dormers and porches can take between 1 to 2 days to install, as they are usually smaller than a main roof installation. For garages, flat roof installation can take anywhere between 1 to 3 days depending on the size of your garage.
Additional Cost Factors
It is difficult to suggest an accurate cost for a flat roof installation as there are many factors that can impact the price. This can include location, tradesperson, and size of house, for example. Additional factors that can affect the cost of a flat roof installation include:
Type of Flat Roof Materials
The most common materials used for on flat roofs are felt, rubber, fibreglass, and lead. These materials all come with different price tags with felt usually on the cheaper side in comparison to lead which is more expensive. The price of materials is not the only factor that can increase the costs. Some materials are harder to install than others which can increase the time it takes to install therefore raising labour costs.
Location of the Property
Location is a big factor when it comes to calculating the total cost of a job. In different parts of the country, the average roofers’ labour costs differ greatly. If you live in and around London and the Southeast of England, you are likely to pay more than those in the North.
Accessibility
If your roof is harder to access, then this can increase the cost of installing a new roof. As the roof is harder to reach, it is a more difficult job that will take more time to complete and will therefore increase labour costs. If scaffolding is required, then this will also increase the cost of the job.
Roof Size
The size of your roof will play a big part in the total cost of a flat roof installation. This is because it will require more material and extra labour when installing your new roof.
Scaffolding Hire
Most roofing jobs will require scaffolding to be able to access taller buildings. So, be sure to factor in or ask your roofer how much it will cost to hire scaffolding when calculating the total cost of installing a flat roof.
What are the different types of materials used for a flat roof?
There are 4 main types of flat roof materials: felt, rubber, fibreglass, and lead. Each material has their own advantages, disadvantages and costs, so if you are unsure on which material is best for your flat roof find all the information you will need below.
Felt Roof
One of the more affordable flat roof materials is a felt flat roof. Made up of felt material, this is a light and easy to install flat roof option. The supply costs per m2 of material, on average, ranges between £40 to £70.
As previously mentioned, a felt flat roof is an affordable option that is easier and cheaper to maintain and install. However, due to its affordability, they are not as durable as other material, can be damaged easily during bad weather and are not the most aesthetically pleasing option.
Rubber Flat Roofs
Rubber flat roofs are made up of EPDM rubber and cost between £80 to £100n per m2.
Like felt flat roofs, rubber flat roofs are fairly easy to install, and it is also an eco-friendlier option if you are looking to be environmentally conscious. The only downsides to rubber flat roofs are that the colour tends to fade over time which can make it look worn out and that if you are looking to DIY your own roof, then this material can be difficult if you are not professionally trained or have extensive experience.
Fibreglass Flat Roofs
This type of flat roof is made up of layers of fibreglass which is strengthened to make the roof more durable. Fibreglass flat roofs are quite popular due to their durability in contrast to other materials such as felt. This material generally costs from £80 to £100 per m2.
The benefits of a fibreglass flat roof include that it is a lightweight material, it is a material that is easy to source and that it is one of the more attractive roofing materials. However, some disadvantages of fibreglass roofs include the material is already cut so it may require more work to fit the material to the shape of your roof, a fibreglass roof is not as easy to maintain, and it should only be installed by professionals due to its fragility.
Lead Flat Roofs
Lead flat roofs are a great choice if you are looking for a long-lasting, water and corrosion resistant roof. In comparison to other flat roof options, lead flat roofs are maintained using a method called flashing. Lead roofs cost between £90 to £110 per m2.
The advantages of lead flat roofs are that they are flexible (which makes it easy to work with), are highly durable and recyclable. The main downsides to lead flat roofs are they are very hard to source and as lead is a toxic material, if it enters your water supply it could cause a potential hazard. Also, it is quite a heavy material so if your building does not have enough structure to support the lead roof then it could lead to sagging.
Advantages and Disadvantages
Before deciding on installing a flat roof, it is best to weigh up the pros and cons. These include:
Advantages of Flat Roofs
It is no wonder why flat roofs have risen in popularity as the roofing choice for many UK properties. Flat roofs offer both short- and long-term advantages which can save you a lot of money in the long run.
Easy to Maintain
As flat roofs are most popular in commercial properties, it is important that they are easy to access. This ease of access allows flat roofs to be easy and regular to maintain which can avoid expensive future repair costs.
Design
Like many roofing options, flat roofs offer many different styles, materials, and techniques to suit many properties and purposes. For the environmentally conscious, solar panels can be installed on flat roofs and many flat roofing options can be made from recycled and recyclable materials.
Durability
As flat roofs are made to be waterproof and weather resistant, they are extremely durable. High quality flat roofs can be long-lasting with the average lifespan around 30 to 40 years with some roofs made from mastic asphalt lasting as long as 50 years.
Cost
With any project in mind, how much it will cost is always at the forefront. The advantage of flat roofs is that they are quite a low-cost option and are relatively cheap, quick to install and are easy to maintain saving on heavy repair costs in the future. Also, a large portion of heat can escape through the roof, however flat roofs use thermally efficient materials that can help to prevent heat loss and save you money on your energy bills.
Disadvantages of Flat Roofs
Some disadvantages of flat roofs include:
Aesthetic
We all know that a roof is there to do its job, but it is also an added bonus when it looks good. Although subjective, flat roofs are seen to lack the character that pitched roofs have. So, if the way your home looks is one of the most important aspects when fitting a new roof, make sure that you like the look of a flat roof.
Drainage
Due to the slope provided by pitched roofs, water can be drained easily from the roof into the gutters. The same cannot be said for flat roofs. Flat roofs usually do not drain as well as pitched roofs as water can collect on top of the roof which can damage the material.
Stability
Although it depends on the size of your home, flat roofs can be less stable than pitched roofs. Some properties may even require extra structural stability to reinforce the structure of larger buildings.
Extensions
If you are looking to building an extension into your loft, then a flat roof is not the choice for you. Flat roofs will limit the amount of space that you have to convert your loft into a liveable space.
