Use it for:

• Carpark Decks
• Heavy Goods Vehicle Service Decks.

Suitable Substrates:

• Concrete, Brickwork, Blockwork or Masonry
• Metal Deck
• Plywood or Timber

• Guaraflex P is manufactured by Guaranteed Asphalt Ltd, a BS kite marked company and member of the UK Mastic Asphalt Council.
• The Guaranteed Asphalt manufacturing plant at Corby is fully computerised and quality checked, and has attained a reputation as one of the most consistent mastic asphalt producers in the world today.

• Guaranteed Asphalt has BS 5750 quality certification.
• In January 2008, UK mastic asphalt became the first industry in the world to achieve the CarbonZero standard: see www.carbon100.com for more details.

General

In the case of precast concrete beams and similar units, adequate end and side restraints should be provided to reduce structural movements to a minimum. The manufacturers advice should be sought on the need for a structural topping with this type of deck.

Surfaces to which mastic asphalt is to be installed should be prepared to a true and even surface free from irregularities enabling the mastic asphalt to be applied to a reasonably uniform thickness. Before work begins all necessary scaffolding should be in position together with sufficient hoisting facilities and measures appropriate for the protection of personnel and the public. It is particularly important that roofs be provided with safety rails and all openings adequately protected.

The deck should be in an adequate condition to receive the mastic asphalt and all necessary builder’s work should have been completed.

Drying Out The Base

Concrete slabs and concrete decks cast in situ should be drained downwards through temporary drain holes formed in the low points of the deck.

Subject to checking their effect on structural strength, the holes should be 25mm diameter, positioned to avoid reinforcement bars in the concrete in accordance with BS 6229:1982. The holes should not be filled until seepage has ceased, before finishing work on the ceiling is commenced. Precast concrete roof decking units with open joints are self draining and holes are not required, but if the joints are subsequently sealed, they should be left open for as long as possible.

The concrete structure must be designed in accordance with BS 8110:Part 1:1997 and able to support all static and imposed loads without undue deflection.

The designer should study the need for movement joints in the structure. Movement joints should be continued at upstands, walls and edges of buildings.

Falls

The falls should normally be provided in the base on which the asphalt covering is to be laid. To ensure adequate drainage, allowance should be made for normal construction tolerances and deflections in order to achieve a minimum finished fall of 1:80. Particular attention should be made to areas subject to pedestrian traffic.

Drainage

Drainage should be provided and designed in accordance with the requirements of BS 6367:1983, Code of Practice for drainage of roofs and paved areas. Outlets should always be located at the level of the waterproof membrane and should be suitable for use in conjunction with mastic asphalt.

Substrates

Concrete

For in situ concrete or hollow tile constructions with an irregular surface, all falls except when provided as part of the structure should be formed by a screed such as given in BS 6229:1982. The surface should be provided with a float finish to a plane even surface free from ridges and indentations.

Precast Concrete Units

Precast concrete units should be used and fixed in accordance with manufacturer’s instructions, finished with a suitable screed or concrete topping to receive mastic asphalt. Falls should be incorporated in the supporting structure or in the screed or concrete topping.

Sand And Cement Screeds

When a reinforced concrete roof slab is overlaid with a screed to provide falls, the screed should be laid in accordance with BS 6229:1982. The surface should be provided with a float finish, even and smooth, free from hollows and ridges. The screed should be designed to remain free from cracks.

Substrates For Ramps

The surface of the concrete or screed on a ramp should be lightly cross-tamped to provide a key.

Tamps should not exceed 5mm in height, and it may be necessary to reduce the bay size to reduce slump during application.

Trafficked Applications

Mastic asphalt provides a versatile answer to the problem of providing paving or combined waterproofing and paving to structures and areas subject to traffic. The specification to be used is dependent on a number of factors such as the type and degree of traffic to which the paved area will be subjected, whether point loading is anticipated and whether the paving is over accommodation areas.

Note: Whilst the product is designed for vehicle traffic some indentations should be expected from long-standing point loads and deformation may result from situations of very high stress.

The product is normally delivered for use in bulk transporters containing the necessary coarse aggregate addition for the nominated paving thickness.

Block materials for traditional site remelt are available for detail work and horizontal areas not accessible by bulk delivery techniques.

Laying - Mastic Asphalt Paving

Each coat should be laid as evenly as practicable using a hand float and undue delay between coats should be avoided to prevent contamination.

Suitable gauges should be used to control the thickness of horizontal work.

Any blows should be pierced and made good whilst the mastic asphalt is still warm.

Joints

The junction between contiguous bays of mastic asphalt should be not less than 75mm from the corresponding junction in the preceding coat.

The edge of the previously laid bay should be warmed and cleaned by the application of hot mastic asphalt which is then removed before the joint with the new materials is made.

It is normal practice to sand-rub mastic asphalt paving. In addition, the surface can be crimped but the advice of the asphalt contractor should be sought as the gradient of the ramps may make control of the crimping roller difficult or it may be physically impossible to crimp edges.

Alternatively, if superior skid resistance is necessary a synthetic resin-bonded grit or other surface dressing can be applied subject to specification.

Solar Reflective Treatment

The use of solar reflective paint on mastic asphalt skirtings and vertical work is recommended. The solar reflective treatment should be applied as soon as practicable after the mastic asphalt has been laid.

Care should be taken to ensure that paints specified as a solar reflective treatment on mastic asphalt are suitable for the purpose and that the specification requires their application in accordance with the manufacturer’s instructions.

General

Guaraflex car parks which have been installed in accordance with the recommendations of this technical guide and the relevant British Standard Code of Practice can be expected to provide trouble-free service provided proper maintenance is observed.

Maintenance inspections should be carried out regularly by persons knowledgeable in mastic asphalt work.

All car parks should be inspected annually, preferably in the autumn, to clear leaves, debris and dirt, which may prevent proper drainage or cause deterioration. Where the car park is in an area of high dust or pollution, or in close proximity to trees, more frequent inspections may be necessary.

Inspection should be carried out both internally and externally. Particular attention should be given externally to car park covering abutments, joints, gutters and outlets and internally to corners, abutments and penetrations. Observations by occupants of building should be noted. During the course of maintenance inspections the wear of the car park should be systematically checked and a note made of any items requiring attention.

Localised repairs should be conducted by a specialist asphalt contractor generally in accordance with the recommendations of BS 8218 : 1998, Section 11 Maintenance and Repair.

For situations not covered by the above please contact Sealtec on 0800 179 000.

Test data examined by the BBA indicate that the product is stable at high temperatures and is flexible and resistant to impact damage at low temperatures.

Accelerated ageing tests indicate a satisfactory retention of properties.

Available evidence indicates that the product should have a life expectancy in excess of that of conventional grades of mastic asphalt used in car parking and HGV Service Deck situations.

With proper maintenance and repair, Guaraflex P should perform satisfactorily for a period in excess of 20 years

This information is intended solely as a guide and to provide general design advice concerning the use of Sealtec products and systems in typical applications.

Before using any product or system, checks should be made to ensure that the product / system are suitable for use in the specific application

This information does not contain the full details required for construction, nor does it constitute an express statement as to fitness for a particular purpose, professional advice is required to take into account all site specific influences.

All technical detail drawings provided in this document remain the property of Sealtec Ltd and cannot be altered without the express consent of Sealtec Ltd. Sealtec Ltd accept no responsibility and makes no warranty regarding the use of this information with non-Sealtec products.

Sealtec Ltd reserves the right to alter or update information parameters and formulations at any time without prior notice.