Roof Cleaning Frequently Asked Questions
Here at LBC, we’ve been cleaning roofs for a long time. At least 9 years in fact and we’ve made a couple of mistakes in our earlier years and that’s why I’m writing this article to educate the home owner on the methods available, risks present and to answer some Frequently asked questions when it comes to roof cleaning.
Some of those questions we get asked on a regular basis include;
Should I get my roof cleaned?
Is roof cleaning necessary?
Is roof cleaning a good idea?
Is roof cleaning worth it?
Is roof cleaning safe?
How much does roof cleaning cost?
What is Softwash cleaning?
Can I clean my roof without using high pressure?
What are the roof cleaning problems?
So I’m going to address some of those questions in this article.
There are four main types of process or cleaning methods for cleaning a roof.
1.Moss removal From Roof
The first type is scraping moss from the tiles.
2.Softwas Roof Cleaning
The second type is soft wash cleaning which is cleaning the roof by applying a cleaning solution to the roof
3.Pressure Wash Roof cleaning
The third type of cleaning is Pressure Washing.
4. Steam Cleaning You Roof
The forth type is for really delicate roofs or when there is some stubborn white spots of lichen that need heat to remove them.
To watch a video and read more about the four different methods of roof cleaning and which one might be best suited to your roof read our blog on The Four Main Methods of Roof Cleaning.
So the first question we need to answer which is often avoided by exterior cleaning companies is:
Is cleaning my roof necessary?
The simple answer is no, its not necessary. Your roof is not going to fail if you don’t have it cleaned. I am yet to see an example of a roof that has failed structurally from lack of cleaning so in those respects in not necessary to have your roof cleaned.
That being said there are many reasons why you might want to get your roof cleaned
If you want a clean roof without moss and are fed up with the gutters getting full, and are fed up with cleaning moss from the patio, then roof cleaning would definitely be a good idea, but only when you appoint an experienced person or company to clean your roof. Personally I’ve seen many roof cleaning jobs done badly by other companies and when they are done wrong the overall result detracts from the property and the property stands out like a swore thumb.
So how do I know if I can pressure wash my roof?
Is often a question we get asked. We assess the structure of the roof and the condition of the roof, but the most important thing to check is the type of tile on the roof. Some tiles are more suitable for pressure washing than other tiles, for example slate or clay tiles have a hard smooth surface and take to pressure washing better than concrete or porous tiles. I’ve Seen many examples of concrete roofs, roof tiles, pressure washed and the surface comes off the face of the tile, leaving it even more porous and damaging the tile and the overall aesthetics of the property. Some concrete tiles have a coloured face and underneath this the concrete is a different colour, over time sandy faced concrete tiles deteriorate and loose much of their sandy face even before any cleaning, this can be seen by granules of sand lining the gutters or by the colour variations seen on the roof when spots of moss fall off. If you look at the back of some of the moss that has fallen from your roof and see what looks like sand granules then its likely you’ve got a sandy faced concrete tile on your roof.
So the first question we ask when speaking to a person who wants to get their roof cleaned, is “What are you trying to achieve? Are you trying to bring the whole roof back to looking like new condition? Or are you more concerned with removing the Moss? If the Moss is the main problem and you’re not entirely concerned with the overall appearance of the roof. Then we’d recommend a moss removal and biocide treatment.” The Scraping is done with scrapers to remove the Moss from the rooftiles and the biocide is a product applied to the roof after the moss has been removed. The biocide is similar to an industrial grade weed killer which helps to kill any remaining moss or fungi that may remain on the roof. The product helps to keep the roof cleaner for longer . And this is the entry level service and the cheapest.
Is Roof Cleaning Necessarily?
Personally, I do not think roof cleaning is entirely necessary. It’s certainly necessary if the person wants the roof to look like new, or is worried about the overall appearance of their property. It’s certainly necessary if the person is fed up cleaning out the gutters regularly, because their getting blocked by the moss or it’s definitely necessary if the person is fed up with sweeping moss from their front door or their patio. But structurally, I don’t think it’s necessary.
There are some people that may argue that a build up of moss can increase the weight on your roof, and that moss can hold water and it can freeze, and create unnecessary strain on your roof. But I haven’t personally seen an example where a roof has been destroyed because it has not been cleaned. So, personally, to be completely honest, I don’t think roof cleaning is entirely necessary, unless you want to improve the appearance of your home, or again, you’re fed up with dealing with moss.
Roof cleaning cost. How much does roof cleaning cost?
This is the question that a lot of people want to know the answer to!
I’m going to try my best to answer it here, but you may also want to read our more detailed blog on why some roof cleaning companies charge more than others
Firstly, it depends on what you’re trying to achieve, the method required for roof cleaning will vary depending on the desired result, how large the roof is and also how accessible the roof is.
So let’s start again with what you are trying to achieve. There are different methods of roof cleaning.
If you’re trying to restore the roof to look in a new condition, you will either have to use a bleach based product, and softwashing / moss removal techniques, or if the roof tiles are suitable a pressure washing method.
A complete transformation where the roof is restored to look like new is going to be on the higher scale of the price pricing guides, as it requires most intensive process. The entry level service would be to remove the moss, or spray an application of a biocide or bleach based product to kill the moss and clean the tiles.
To give you some examples: Let’s say a standard terraced house with a standard pitch roof up and over, and you just wanted moss removal. This is likely to cost anywhere from between £650 and £1100 pounds plus VAT. The process for this is to gain access to the roof, ideally using a cherry picker or scaffolding tower, Scraping the moss from the roof, treating the tiles with the biocide application, which deters future moss growth, it kills all the moss spores and algae spores, to help keep the roof cleaner for longer. And also cleaning out the gutters, which will likely get full in the process of cleaning the roof.
Now lets look at this same terrace property, covered in moss, but the client wants an overall transformation of the roof so the roof looks new again bringing the tiles back to their original colour .
If the roof tiles were suitable, so they were a clay tile rather than a concrete tile. And maybe the tiles had started to go black, or dark, or dull, or green with dirt, or algae and the client wanted to restore them to their original colour, which was a nice bright red. This same job, is likely to cost somewhere between £950-1500+vat. Again depending on access.
How much does it cost to clean a standard roof on a semi detached house?
So again, depending on the cleaning method, and the accessibility, the price for this can range anywhere from £950 to £1500 pounds. And the price for a detached house, a larger detached house, for a full roof clean as in a transformation to restore the roof, can start from £1500 pounds and go upwards depending on the size, the access, etc.
What is Softwash roof cleaning?
Soft washing is roof cleaning without pressure washing and instead cleaning with chemicals such as bleach based products that kill all the organic growth on yuour roof.
What is no pressure roof cleaning?
What is low pressure roof cleaning?
These are all the same type of question, so here are some questions that will relate to cleaning of roofs without pressure washing. What’s commonly known as Softwash roof cleaning.
This is applying chemicals to a roof to clean the roof. Often a bleach based product, which gives faster results when compared to other biocides that can be used for cleaning roofs. If cleaning your roof with little moss, then the soft washing method can often be done from gutter level and without the need of accessing the roof, or without the need of walking on the roof tiles. As many people are afraid of damaging or cracking the tiles. Softwashing works as it is done with a bleach based product, a strong bleach based product called sodium hypochlorite, which acts as a biocide and kills any living pathogens, such as any moss or algae or fungi that may be present on the surface.
Roof cleaning problems.
Many companies don’t talk about possible problems when it comes to roof cleaning. But from my years of experience, we have seen that customers are generally concerned with the risks, and the potential problems of cleaning their roofs. And there definitely is some to be mentioned. So what are the risks? What are the possible problems of cleaning the roof? Or, why do people often ask, “Is it safe to clean my roof?”.
So the possible problems start when you get an inexperienced person attempting to clean the roof. An inexperienced person may think that it is perfectly fine to try to pressure wash any type of roof. But this is not the case, and this is why here at LBC, we inspect every roof before cleaning. Because we know that some tiles are not as suitable to pressure washing cleaning methods as other tiles.
Other things to look out for …
If the roof is in bad condition and there’s missing tiles, then there may be a risk of water getting through. If the cleaning method is done wrong and the person cleaning the roof is pointing the water jets upwards, then there is a potential for water to get up and under the tiles.
If an inexperienced person tries to pressure wash a certain type of tile that has a concrete type face, or a sandy, gritty upper layer, they’re likely to remove this layer during pressure washing and make the tile more porous, This leads to a change in the appearance of the roof and it can often be appear as pale yellow in appearance. This can also leave the roof open to potential further damage.
The other potential problems that exist when choosing a roof cleaning company are if any damage or accidents happen while you’re having your roof cleaned, you want to ensure that the person or company carrying out the roof cleaning is insured to do so in case any accidents or issues do occur.
Any reputable roof cleaning company will not mind you asking for proof of their public liability and relevant insurances.
You need to choose a reputable company that is going to agree up front to cover any accidentally damaged tiles. As this is possible, especially if cleaning the roof using a roof ladder or rope access, to access the roof. This is a possibility, so you want to make sure that the person cleaning the roof accepts to replace any damaged tiles. For your peace of mind, you should request before and after pictures to ensure there is no damage. If there is any damage, you should look to get the roof repaired before any cleaning, to minimize the risk of any water penetrating through the tiles.