A tarmac repair is highly likely at some point mainly due to degradation caused by weather or oil spills. Unsuitable sub base materials can also give way causing surface tarmacadam layers to sink.
A tarmacadam repair – Weather
Any moisture trapped in a tarmacadam driveway will expand when the temperature goes down to zero. If you imagine tiny air pockets full of water which then freeze, you’ll get the picture. As the moisture expands it pushes tarmacadam up. Vehicular usage exacerbates the problems and aggregate starts to come away until eventually a hole forms.
A tarmacadam repair – Oil, petrol or diesel spill
When a vehicle leaks onto a tarmacadam driveway patches are formed and apart from not looking very nice the spillages thin down the ‘binder’ (which keeps the tarmacadam together). The thinning of binder will cause the ‘macadam’ (aggregate) to separate and come loose.
A tarmacadam repair – Tools and step by step process
Repairing tools: Broom, spade, club hammer and trowel. A bolster should be sufficient to cut out small areas but a disc cutter may be required for larger areas
Use the hammer and bolster/disc cutter to cut around the damaged area and extend at least 100mm around the area to be repaired.
Ensure all tarmacadam is removed down to sub base by using the the spade or small shovel to remove any old tarmacadam and loose base materials.
If the sub base is loosened it will be necessary to compact this by using the club hammer.
Use the trowel (or if larger area- spade or shovel) to lay the cold lay compound. This is usually very sticky and heavy to put in and surprisingly takes quite a bit of time. Ensure the level is at least 10mm above the level that is the finished level.
Tamper down with the club hammer. This will compact the compound and if the level goes below desired finished level, more compound will need to be added and tampered down.
Job done. A new tarmacadam repair will look patchy but after a few years it should blend in.
Tarmacadam repair – Alternatives
There are other ways of repairing tarmacadam including the use of infrared. This heats an area of tarmacadam so that it can be re worked. Then it is simply raked into position and added to, if necessary.
Unfortunately, due to the equipment needed these types of infrared repairing machines are mainly used on roads. If a large driveway is in need of multiple repairs it may be worth looking up a tarmacadam repairer that uses such equipment.
Tarmacadam contractors will usually be reluctant to price up and repair a tarmacadam driveway unless there are significant sized repairs to carry out. A more effective approach is to ask a local contractor that is working close by if they will carry out a repair for you. You may not be able to pay with a debit card though!
Important Note: Tarmac is the common term used by almost everybody but its correct name is tarmacadam, asphalt or Bitmac (as used in the trade). Tarmac is a trading name of Lafarge, a conglomerate. Therefore all references on this site will be about tarmacadam or asphalt.