Is Roof cleaning necessary?
If you look around your local areas you will find 80-90% of homes roofs are covered in unsightly moss and algae.
Not only does this look unpleasant to the eye heavy moss growth on the roof can cause damage to your roof over time.
The moss acts like a sponge soaking up the moisture in the air and rainwater.
When the moss then freezes, it expands on the surface which can then lead to cracking in your roofs pointing, lifting of tiles. We have also seen moss eat its way into tiles leading to the surface becoming defaced.
How do you clean a roof?
The most common ways to clean a roof are either by pressure washing the roof or a gentler approach is soft washing the roof.
Pressure washing the roof is carried out via accessing the roof by either using access equipment such as a MEWP (cherry picker) or using rope access and roofing ladders. If the roof is fully accessible some pressure washing the roof can be carried out from a portable scaffold tower and telescopic lances.
Roof Moss removal also know as Soft washing the roof is a way of cleaning the roof without the need for a pressure washer. Again, this is done either via a portable scaffold tower and telescopic roof scraping tools or from gaining access to the roof via a roofing ladder and securing the operator using fall arrest equipment. The bulk of moss is manual removed followed by a moss and algae treatment then applied to kill any remaining moss/algae which in turn results in a cleaner roof over a period of time.
What chemicals are used to clean roofs?
The main chemicals used to clean a roof are sodium hypochlorite based products which give instant results.
The sodium hypochlorite based products are usually sprayed on the roof after the moss has been removed and then washed off as it is not recommended to leave this product on the roof.
Another chemical used is a biocide treatment (DDAC) which is applied to the tiles but instead of being rinsed off this is then left on to work over a period of time with the natural weather cycles.
How often should you clean your roof?
Once your roof has been cleaned if an application of biocide has been applied after the clean the roof should stay clean for an average of 3-5 years. This time scale depends on the property’s environment as a more rural home is more likely to show signs of regrowth faster than a townhouse.
To keep the roof cleaner for longer maintenance treatment can be applied once the roof is showing signs of regrowth which will then keep the roof cleaner for many years to come.
Does cleaning your roof damage it?
This is a question that gets asked a lot, many people are under the allusion that cleaning your roof will damage the roof tiles taking of a “protective coating”.
An aged concrete roof will already have lost the coloured surface of the tile with the UK’s harsh weather cycles and this is why you find when aged concrete roofs are cleaned they all end up the same colour.
Using the correct pressure and nozzle along with using a professional roof cleaning company either the soft wash or pressure washing cleaning option will not cause damage to your roof.
We made a little video to show 5 of the most popular roof tiles on UK homes both before and after being pressure washed
As you can see in the video using the correct pressure the roof tiles were not damaged at all.
Soft washing the roof is even less harsh as the whole roof cleaning process is carried out using no pressure whatsoever. The moss is removed by handheld tools and the treatment are applied via low-pressure sprayers.
How much does it cost to have a roof cleaned?
Every roof is different and there are many factors to take into account when pricing a roof clean.
When a company comes to quote your roof clean will take into consideration the size of the roof, the amount of moss present on the tiles, access to the roof, tile type and so on.
So, it’s not just as easy as saying roof cleaning cost X amount.
A guide price for your roof to be cleaned via pressure washing after speaking with many roof cleaning company’s across the UK we found vary from £8-15 per sq.m.
To receive an accurate quote a professional roof cleaning company would need to visit the property so they can fully see the roofs access, soiling, size etc…
How much does it cost to remove moss from a roof?
Soft washing or removing the moss from a roof is usually a cheaper option than pressure washing.
The thing you need to ensure when having your roof soft washed is to find out exactly what product the company will be applying to your roof to after the moss has been removed.
The biocide treatment is what will kill all biofilm and protect your roof from any new regrowth so using a top-quality treatment is essential to ensure you get the best results possible.
The average price for roof moss removal and soft washing a roof we found to be in between the price range of £5-12 per sq.m so on some occasions can be half the price of pressure washing a roof.
We hope this has helped answer any question or queries you may have had regarding having your roof cleaned, for any further advice or information regarding roof cleaning please feel free to browse our website or call us on 01952 327474 where we will more than happy to answer any question you may have.