Removing moss from a mono block driveway

Moss On Monoblock

A mono block driveway is a surface that should last you for many years. If laid properly, on both hardcore and around 50mm of sharp sand, the interlocking blocks will spread the heavy weight of vehicles evenly, so a smooth and level surface should be maintained. A well-designed driveway can also help a property to look good, but a mono block surface does need to be looked after. Cleaning mono block driveways and paths has always been a time-consuming process but, whilst mono block surfaces certainly look very nice and are extremely functional, it can be a breeding ground for moss, lichen & weeds especially between the blocks themselves. However, there are many ways to successfully clean mono block depending upon the tools at your disposal and how much work you wish to do.


Before you do any chemical treatments on your mono block, we recommend you try to remove as much growth and loose dirt as possible. Sweeping is the easiest way to do this. This initial clean will allow the moss killing products to work more effectively and quickly and will, ultimately, save you both time and money. For help with this initial cleaning, why not look at our SPECIALIST BRUSHES. The WIRE BROOM & HANDLE is ideal for getting between the blocks but is big enough to ensure that the job will not take all day. It is also very strong so will remove any dirt or growth from the blocks themselves.

If the area has weeds, these should be treated with a quality WEED KILLER. They should be treated BEFORE you undertake any moss killing. We normally suggest applying a weed killer 5 - 7 days before you apply moss killer. It is better to use a professional weed killer rather than 'pulling' the weeds as this method will only result in the return of the double quick time. Should your mono block surface have any oil stains we recommend using SP STRIP which is a powerful brick cleaning acid. Simply dilute, apply to the surface, brush and rinse. Using SP STRIP will not only remove oil stains but will also deep clean the blocks themselves.

The most important area to brush is in between the blocks. This may sound obvious but it must be remembered that the more growth you can remove before treatment, the quicker and more cost effective the chemical treatment will be. Should you decide that a smaller wire broom would be better for your area, we do have a professional quality WIRE JOINT BROOM which will allow you to brush the joints as opposed to the whole surface.

Treatment Option 1

After brushing your mono block, spray the area with RAPID MOSS & ALGAE KILLER - Batiface. This kills the moss & algae growth on contact and should be left on the surface for between 15-30 minutes, after which the area should be washed with either with a hosepipe and brush or, ideally, a SMALL pressure washer. The pressure washer not only rinses away the product but also removes the dead growth from the surface and between the blocks. Please don't worry about using a pressure washer on your mono block. Just because you are using higher pressure it is not going to automatically result in your driveway sinking or blocks ending up in your neighbour's garden. If you use the pressure sensibly then it can make the cleaning much more effective. Once the area has been cleaned and is dry, you can undertake any remedial works that may be required such as re-jointing. After this we advise the application of CONCENTRATED MOSS & ALGAE KILLER - Baticlean CR. This will kill any moss that you may have missed during the initial cleaning but will also kill the moss spores. As the BATICLEAN CR should not be rinsed it will stay on the surface to inhibit moss re-growth.

Our full range of sprayers can be found HERE.

Treatment Option 2

Alternatively, after the initial preparation of your mono block just spray the area with BATICLEAN CR. It must be remembered that this is a systemic product therefore, if being used to kill moss growth, it must be able to be absorbed and should only be applied to a dry surface on a dry day. Better results will also be obtained if the growth is dry. One of the issues with the growth between blocks is that whilst the visible moss may be dry, it will be drawing moisture from beneath the blocks. It is for this reason that we recommend removing as much of the growth prior to a treatment or waiting for a short dry spell (2-3 days) before applying.

Future Care

You should always try and keep your mono block clean and tidy. Remove leaves and cut back anything that causes shade across the area, especially during the winter months. Brushing the surface occasionally will help and does not take too much effort. In addition to this you can treat it every 10 - 14 months by simply brushing the surface and, on a dry day, applying a new coat of BATICLEAN CR or just wait until the first signs of new growth appear before applying a new coat.