Cost of Cleaning a Roof

Cleaning your roof is the perfect way of refreshing your home’s appearance and keeping the structural quality of your roof intact. Moss, dirt and debris not only looks unappealing, but can also damage your roof materials and lead to expensive water damage. Dependant on the size of your roof, the cost of cleaning will vary from property to property. In this article, we will talk you through the process of roof cleaning as well as all of the potential costs involved.

Why Get Your Roof Cleaned?

There are a multitude of reasons for cleaning your roof:

• Aesthetics – Cleaning your roof can instantly refresh the appearance of your property. Removing dirt and moss can make your roofing tiles look brand new once again with no need to replace the materials.
• Lifespan – Regularly cleaning your roof can significantly enhance it’s lifespan. Similar to a sponge, moss absorbs moisture. Over an extended period of time, the moisture can move underneath the roof tiles, causing rot and other expensive structural damage.
• Wildlife – Moss can be known to attract wildlife such as birds and insects. Not only does this affect the appearance of your property, but it can also cause damage to the roof tiles and guttering.
• Guttering – Moss and debris covering your roof can fall down into the guttering and cause blockages in the drainage system. This hinders the gutters/downpipes and leads to costly water damage.
• Property Value – If you are looking to sell your property, a clean roof can significantly increase the value and interest of your home. A moss-free roof will give the buyer the impression that the property is well-cared for and kept in good condition.

What Does Roof Cleaning Involve?

There are a selection of roof cleaning methods, dependant on the state, size and type of roof you have. 

Power Washing

A lot of companies will prefer to use a pressure or power washer to clean moss and dirt from your roof. It is a faster technique that flushes the debris on to your driveway/the ground below to then be disposed of. This method is generally safe for most properties, however, may not be suitable if your roof tiles are particularly old or vulnerable.

Pressure washing can run on average from anywhere around £8 per m2 to £15 per m2.

Manual

Another method is manually removing the moss and dirt using a scraper and brush, then applying a biocide treatment to minimise re-growth. Although this technique is more time consuming, it is generally more affordable and safer for weaker roof materials. 

Including the moss removal process and biocide, the average cost for the manual cleaning method runs from around £5 per m2 to £12 per m2.

Breakdown of Factors Affecting Cost

There are a selection of factors that will affect how much it costs to have your roof cleaned.

Property Size/Type

The general rule is the larger the scale of your property’s roof, the more expensive the cleaning process will be. Before the cleaning is carried out, the contractor will evaluate the type and size of your roof as well as accessibility to advise on the best cleaning method and pricing. Below, we have created a table compiling estimated average roof cleaning prices based on varying house sizes. This is a good place to start to get a rough idea of costs. (Price estimates from Loftera.)

Property Type/Size	Minimum Cleaning Cost	Maximum Cleaning Cost
Small Terraced House	£350	£450
Semi-Detached House	£450	£600
Average Detached House	£600	£800
Large Detached House	£800	£1000+

 

Area

The area in which you live can have a significant impact on how much roof cleaning will cost. The table below demonstrates a collection of price estimates based on the area in which the property is situated as well as the scale of the company. (Price estimates from Roof Advisor.)

Area – One Main Job (Small Scale)	Average Cost
London	£400 - £500
Midlands/South	£350
North	£300

 

Area – Up to 5 Workers (Medium Scale)	Average Cost
London	£600
Midlands/South	£450 - £500
North	£400

 

Area – Up to 10 Workers (Large Scale)	Average Cost
London	£850
Midlands/South	£550 - £650
North	£450 - £550

 

What Am I Paying For?

When hiring a contractor to work on any part of your property, you may be wondering what your cost is actually paying for. In the handy table below, the costs for each aspect of the job have been broken down into individual percentages. (Price estimates from Loftera.)

Part of Job	Cost	Percentage of Cost
Materials	£60	10%
Labour	£360	60%
Scaffolding	£180	30%

 

Materials

Each company will have their own technique, materials and treatments that they use for the cleaning process. Usually, when higher quality products are involved, this will lead to a higher cost.

If a pressure washer is used, the roof will first need to inspected and assessed for any missing or damaged roof tiles. If these need to be replaced, a further percentage will added to the overall cost for materials. After washing is complete, a moss killer will then usually be applied to prevent the moss from re-growing.

During manual cleaning, the materials cost will compensate a good quality biocide, roof scraper, brush and potentially a roof sealant to finish.

Labour

Depending on the condition of your roof, size and accessibility, the cost of labour will vary. For example, if you live in a large detached property with heavy moss coverage, the roof space will be harder to access and take longer to clean, increasing the costs of labour.

A reputable roof cleaner will always carry out an inspection of the roof before beginning the job. This is to check for damaged or vulnerable sections of your roof as well as evaluating the volume of moss that needs to be removed. A risk assessment will be carried out with full information about access, safety and repairs.

On average, the timescale for pressure washing is approximately 1-2 days whilst manual scraping can take up to 2-3. Additional labour such as roof repairs and sealant application can add on an extra day and increase cost. The cost of sealing a roof after cleaning is priced from around £25 to £40 per square metre. An experienced roof cleaning company will be able to give you an accurate timeframe for completion after the initial roof inspection.

Scaffolding

Scaffolding and specialist equipment will need to be used to ensure safe access to the roof space. The cost of this will depend on the height and positioning of your roof.

How to Avoid Unreputable Companies

As with any hired tradesmen work, there will always be companies that are unreputable and provide an unfit service for quick cash. They will leave you out of pocket, in a worse situation than you started in and can possibly introduce dangerous risks if the job has been carried out incorrectly. It can be tricky to spot a rogue company, especially if you do not have much experience with the roofing trade.

We have compiled a helpful checklist of things to look out for when hiring a company to ensure you don’t have this negative experience.

Too Good to be True

You’ve been quoted an unbelievably low cost by a company that seems almost too good to be true. That is because it usually is. It is valid that companies will vary costs dependant on the area of the country they are working in etc. However, you should apply the logic that if the price seems way too low for no apparent reason, the service you will be provided probably won’t be up to a high quality standard.

Take a look at the tables further up the post and ask yourself if the price quoted fits anywhere in the average estimation based on where you live and the type of property you own. If in doubt, always get a second professional opinion from a different company and compare prices.

Reading Reviews

Reading reviews online is a fantastic way of evaluating the experiences of other customers from a company. Pay close attention to what the reviews are saying. If you are finding that the majority of the ratings are pretty low and the customers have highlighted consistent problems with the company’s work, then it may be best to look elsewhere.

Ask Around

Getting recommendations from neighbours, friends and family gives you a first-hand experience from somebody you can trust. If they are pleased with the service and happy to recommend, this is a good sign that the company is legitimate and trustworthy. 

Tradesmen Site

As tradesmen’s sites only deal with reputable companies, you will be able to pick out the trusted professionals that have been guaranteed by high-quality tradespeople. They should be able to provide insurance certificates and other important credentials to prove that they are legitimate.

How Busy/How Much Experience

Although a number of factors can impact how busy a company is, if they are not getting many customers for what seems like no reason, this may be a signal that something is off. Although it may seem like the right thing to do to offer more work to companies such as this, you need to think that less work often means less experience, which could have an impact on the quality of the job done.

Can I Clean the Roof Myself?

A seemingly obvious method for saving yourself some money, would be to cut the labour costs and DIY the cleaning yourself. In most cases, you will see that homeowners do employ an experienced worker/company to carry out the job instead of attempting themselves. Why is this?

Firstly, professionals have the training and experiencing to evaluate potential risks and ensure the job is carried out with full safety precautions in place. On very high roofs, you put yourself in danger of falling.

Additionally, you may overlook certain parts of the inspection process and begin cleaning without the necessary repairs/replacements. This could cause more damage and lead to a higher costing job than you began with.

Although it is recommended to leave the full scale cleaning to those with experience, homeowners can take on certain aspects of upkeep and maintenance as long as it is carried out safely. Tending to your roof semi-regularly and removing excess moss can widen the gap in between professional cleaning jobs, saving you money that way.

Take a look at our handy article on moss removal here as well as our guide to cleaning roof tiles here for more in depth information on the process.

In terms of materials, there are a multitude of different products you can use. For example, an off the shelf moss remover and algae remover are affordable options with formulas specialised for high-quality removal performance.

How Often Should my Roof Be Cleaned?

It is recommended that you have your roof cleaned or at least inspected for moss around once a year before winter begins. However, the rate at which the moss grows back will depend on:

• Positioning of the roof in relation to sunlight
• Quality of the previous cleaning job
• Method of cleaning/moss removal
• Sealant coating used

If your roof is north facing and the moss has been manually removed, the average timescale for re-cleaning can be up to 2-3 years. This can stretch even longer at 4-5 years for roofs that are power washed and then treated with a good quality sealant.

Moss usually takes longer to grow on south-facing roofs due to the lesser amount of sunlight. The timescale for manually cleaned roofs will move up to around 3-4 years and power washed as long as 5-6.

If you notice large amounts of re-growth or can see damage caused by dirt and debris within these timescales, then it always best to have your roof assessed to prevent unnecessary damage to the structure.

To Conclude

Keeping your roof clean increases the visual appeal, practicality and safety of your roof space. Large levels of untouched moss, debris and dirt can lead to a variety of expensive damages that are completely avoidable with regular inspections and upkeep.

Whether your roof requires minor maintenance or is due for a full-scale clean, it is always better to get the job done ASAP rather than leaving it for later. Take a look around and find a reputable company that you can trust and keep using into the future. Additionally, stock up on home maintenance products that allow you to keep your roof in high-quality condition in between cleans.

If you have any further questions or queries, don’t hesitate to get in touch with our helpful customer service team. Just give them a call on 01295 975158, email [email protected], or leave a message in the handy live chat.