Do you have an unsightly patch of oil on your drive? Those who have a passion for tinkering with cars, motorcycles or other machinery will understand how annoying it can be to deal with such spills on the driveway. With concrete, such spills can be mopped it, which is the reason petrol stations have concrete and not tarmac surfaces. So, how to handle a petrol-stained driveway?
The reason why petrol causes problems with tarmac is that part of the sticky glue that binds the tarmac together is bitumen and this is an oil-based substance. Petrol can dissolve and break up a tarmac road surface. It is the same for other oil by-products as well, such as paraffin, light oil and diesel.
If you are present when a spill occurs, it is best to mop it as soon as it happens with an absorbent cloth, warm water mixed with detergent and a brush but do not put too much pressure on the tarmac or it can loosen. Detergent and water should help to break down the petrol, so that you can then rinse with plenty of water.
If you are not aware of a leak or spillage, the only real solution to get rid of the stains and the possibility of damage is to remove the top surface where the patch is and re-patch with fresh tarmac. It will not be smooth, however, so any fresh patch will always be visible.
If you leave the petrol, it will continue to break down the asphalt, loosening the aggregate layer. Whenever the pressure of vehicles passes over it, it will push out the aggregate, leaving an ugly hole. Better to get it fixed sooner rather than later.
A good patch method is to cut out the patch with a power saw to about 5cm deep. Mark around the stain leaving a gap of 10cm on each side. This is to ensure all the petrol from the subsurface is included as well as what you see from above.
When the area has been cleared of loose aggregate, the edges of the hole should be covered with a tarmac jointing compound. This prevents water from entering the edge of the hole while the patch sets. It is always best to have a professional deal with any tarmac repairs you need. For a Tarmac Company Bristol, visit a site like Thornbury Surfacing, a leading Tarmac Company Bristol.
The hole is then filled with a tarmac repair product, which consists of bitumen mixed with flame retardants. It will be applied in two to three layers, compacted down with a lump hammer and a metal plate.
After the patch reaches the same level as the rest of the drive, more tarmac jointing compound is required around the edges. This will make the patch visible but is an important part of the work to prevent water from entering and breaking the seal between the patch and the whole drive.