Mastic Asphalt Car Parks are a tried and tested solution for the demands of a modern car park. It provides the perfect combination of a long-life span, durability to heavy traffic, cost effectiveness and the ease of installation.
Can you repair a mastic asphalt car park? Well let’s start with the facts first shall we, yes - in fact mastic asphalt is one of the very few waterproofing materials that can with the right preparation and application can be rectified easily.
Mastic asphalt damage can be easily recognised by anyone, yes anyone, once expertly laid by hand crafted tools of an asphalter the final finish of this age-old heritage system leaves a completely seamless waterproofing layer laid to the falls of the roof.
So how do you know if your mastic asphalt car park or walkway terrace need repairing? What should you look for? what kinds of damage can be caused to the asphalt? and why does it happen?
Before we start… let’s talk about a common myth banded around regarding mastic asphalt car park, beliefs that “new asphalt cannot be made to old” mastic asphalt is a complete rubbish. Impact damage and movement cracks are readily seen in this totally seamless waterproofing system, mastic asphalt is in truth one of the ONLY materials that can have problems identified and rectified easily.
The base substrate on which the mastic asphalt is to be laid should be made right and adjusted to a contour approximating to the very last contour and swept easy of debris and status water.
B Grade S: For roads, footways, roof top car parks
T50 Grade S and similar applications
T50 Grade H: For bus stops, loading bays and areas subject to very high stresses
Polymer modified High performance grades of paving incorporating polymer modified binders are available from manufacturers and are designed to meet the demands of modern construction.
|Grade||Application||Thickness range||Nominal size coarse aggregate||Coarse agg. content, % by mass of total mix|
|S||Footways||20-30mm||3mm||25 ± 5|
|S||Roof top car parks||25-35mm||6 or 10mm||30 ± 5|
|S||Roads & carriageways||30-50mm||6 or 10mm||40 ± 10|
|H||Heavily stressed areas||40-50mm||10mm||45 ± 10|
Note: Indentations are to be expected from long-standing point loads and deformation may result in situations of very high stress.
When tested in accordance with BS 5284:1993, the hardness number of the mastic asphalt at the time of manufacture and prior to the addition of any coarse aggregate shall be:
Grade S 30 to 60 @ 25 degrees Centigrade
Grade H 15 to 25 @ 25 degrees Centigrade
The crossfall of roads with straight crossfall should not be more than 2.5% nor less than 2% unless the purchaser gives other directions. With roads to be cambered the average fall of the finished surface from the crown to the channel should not be more than 3.3% nor less than 2.2%. These recommendations for crossfall do not apply to curves with superelevation.
Here’s some straight forward signs to look for on your asphalt survey:
• Bumps on the mastic asphalt surface that are raised and often rounded in shape. Visually to the eye these will appear to be obvious and unnatural in relation to rest of the flat areas. They are generally caused by trapped moisture beneath the surface of the asphalt and can be singular or multiple in number (also referred to as blows or blisters the latter being in the final stages of the defects penultimate damage).
• Blisters these are often raised from the flat contours of the mastic asphalt surface circular in appearance to blows/bumps but with the top split or cracked open. To the eye these will appear to be again obvious and unnatural, not unlike small volcanos on the flat areas. They are generally caused by trapped moisture beneath the surface of the asphalt and can be singular or multiple in number.
• Cracks & Splits can be caused by trapped moisture, water seeping into a crack or split can be very damaging. In winter time rainwater in slits/cracks often turns to ice expanding the water volume and as a result pushes against the asphalt increasing the crack. This pushing can cause then wrinkles/creasing cracks or splits often also due to thermal movement in the substrate or impact damage are very clear to see.
Most products and manufactured construction materials have to be maintained so stands to reason if you want something to last you need to take care of it so use common sense. Water stains to ceiling and damp wall damage below car park and walkways can often be caused by a defective mastic asphalt membrane. Small leaks are potential signs that tell early tales that unhindered can cause long terms problems when it comes to water ingress and it’s of high importance to make certain any asphalt surfaces are taken care of and repaired correctly.
Mastic asphalt surfaces coupled with deterioration, asphalt can become damaged, eroded or otherwise defective.
Specialist repairs and maintenance requires assessments of the exterior surface elements swiftly so that small problems do not become very unfortunate ones. This regular attention can aid in eliminating surface ageing and result in substantial rewards ultimately extending the life of the mastic asphalt by years.
Mastic Asphalt is a hot poured liquid waterproofing membrane material that is used for flat roofing, car park, walkways terrace, floors, paving and basement tanking. The mastic asphalt coating is applied to the surface substrate to form an extremely strong and watertight bituminous surface black in colour.
The bitumen element of any mastic asphalt coating should be especially noted when applying any form of repair product coating such as sealants from mastic guns. Oil based mastic compounds leach into the mastic asphalt coating and will slowly break down the bituminous content as any oil-based product will attack the chemical properties of mastic asphalt.
Mastic asphalt coatings contain a bituminous compound which is a by-product of the petroleum refinement within this compound are very tightly bound particles. Additional strength can be added for various uses of mastic asphalt coatings known as “grades “these have aggregate blended. Aggregate types can vary dependant on use but often lime is used for roofing grades and granite is added for paving use. This material is known as mastic Asphalt.
• Bumps on the flat surface
• Cracks in the surface
• Vertical upstands or flashings damaged
• Blistering of the Mastic Asphalt coating
• Cracks, wrinkles or splits appear
• Sagging and Pulling surface problems
• Pooled or standing water
• Rapid ageing
All of these issues can be easily rectified during annual maintenance visits by our specialist team of fully qualified mastic asphalt craftsmen.
“I found Heritage Asphalt by accident on the Internet. It was a video about asphalting steps. I called Ryun who was very professional and had a great deal of experience and knowledge. The job was booked in straightaway and a team set about taking off old asphalt rebuilding and repairing the big Victorian staircase and then asphalting. The finish was quite amazing, these guys are very skillful at what they do and My husband and I were delighted. They were a professional team really hard working and highly recommend them.” Customer in London
“First class job - very polite. Couldn't have chosen better - highly recommend this company. Thank you.” Mrs Susan Knight
“Perfect service. Will happy use them again if required to.” Trevor Trim
“This company goes 'the extra mile' in both workmanship, customer satisfaction and consideration.” Mrs A Lighterness
“Ryan and team arrived, late afternoon, as agreed, to review balcony, approx. 25m2, 3 sides fed by tiled roof and one long length hand-rail. Problem, 3 leaks in different places from 10yr old asphalt roof. We discussed the problem and Ryun suggested a choice of two plan of action. We found his quotation very acceptable. This work was completed as agreed, in only a few days, to our complete satisfaction. Eight months after completion, I can now report that after a very wet winter, the roof is in a sound state. An excellent job done.” Customer in Cambridge