Sika Everbuild 903 5 Litre Black Jack Bitumen Trowel Mastic - 90305

Sika Everbuild 903 Black Jack Trowel Mastic Fibre Reinforced 5 Litre 90305 

Trade Size - Trade Price - Money Saver Deal

Barcode: 5029347009359

MPN: 852674

Model: 90305

Size: 5 Litre Tin

Colour: Black

This product is in transition from Everbuild Packaging to the new Sika Packaging

Overview

Sika Everbuild 903 Black Jack Trowel Mastic Fibre Reinforced 5 Litre is a heavy-duty bitumen-based waterproofing compound designed for demanding exterior repair and sealing work. Supplied in a trade-size 5 litre tin, this thick black trowel-applied mastic is ideal for patching roofs, sealing gutters and filling cracks, holes and joints on a wide range of surfaces. The fibre reinforced formula helps provide a tough, weather-resistant seal, while the non-setting nature allows the material beneath the surface to remain flexible for movement. It is a practical trade choice for roof maintenance, general waterproofing and repair jobs where a robust bituminous seal is needed.

Key Features

• Fibre reinforced black bitumen trowel mastic

• Trade size 5 litre tin for larger repair jobs

• Suitable for waterproofing, stopping, bedding, bonding and sealing

• Forms a surface skin while remaining flexible beneath

• Ideal for roof repairs, gutter sealing and patching cracks or holes

• Adheres to felt, asphalt, metal, concrete, slate, timber and more

• Suitable for use with bituminous surface coatings

Specifications

• Brand: Sika Everbuild

• Product Name: 903 Black Jack Trowel Mastic Fibre Reinforced

• Model: 90305

• MPN: 852674

• Barcode: 5029347009359

• Size: 5 Litre Tin

• Colour: Black

• Product Type: Fibre reinforced bitumen trowel mastic

• Pack Type: Trade Size – Trade Price – Money Saver Deal

• Packaging Note: This product is currently transitioning from Everbuild packaging to new Sika packaging

Applications

• Patching holes and cracks in roofing surfaces and bituminous coatings

• Sealing and repairing gutters, joints and external gaps

• Bedding, bonding and sealing on felt and asphalt surfaces

• Filling gaps on corrugated iron, fibre cement, slate and metal sheets

• Waterproofing concrete, timber and sand cement surfaces

• General exterior repair and maintenance work

How to Use

• Make sure the surface is as clean, sound and dry as possible before application, removing loose dirt, grease and debris

• Apply by trowel, pressing the mastic firmly into cracks, holes, joints or the repair area

• For cracks, force the compound well into the gap and finish with a band over the crack to bridge either side

• For larger holes or weak areas, apply the mastic and embed a closely woven glass fibre membrane, overlapping the damaged area

• Allow the first application to settle before applying a second coat where required to fully cover the repair

• Always read the manufacturer’s Technical Datasheet prior to first use

Cracks and Holes:

• Force the compound into the crack finishing with a 25mm band at a 3mm thickness running the length of the crack so your bridging the crack either side.
  
• For large cracks and holes apply the compound over the area to be treated and embed a closely woven glass fibre membrane into the compound overlap the crack or hole by 50mm.
• Allow to dry and then apply a second coat, fully covering the reinforcing membrane.

Corrugated Iron and Fibre Cement Roofing Sheets:

• If a roof sheet is cracked, clean and prime with Bitumen Flashing Primer

Sika Everbuild 903 Black Jack Trowel Mastic Fibre Reinforced 5 Litre – Key FAQs

• What is Sika Everbuild 903 Black Jack Trowel Mastic used for?
  It is mainly used for roof and gutter repairs, patching holes, sealing joints and carrying out general exterior waterproofing repairs on bituminous and other common building surfaces.

• Does Black Jack 903 remain flexible after application?
  Yes, it forms a surface skin while the material below remains non-setting and soft, allowing for a degree of movement in the repaired area.

• What surfaces can this trowel mastic be used on?
  It can be used on mastic asphalt, roofing felt, corrugated iron, cast iron, fibre cement, slates, lead, copper, zinc, concrete and timber.

• Can this product be used for larger cracks and holes?
  Yes, for larger repairs it can be used with a closely woven glass fibre membrane to help reinforce the repaired section.

• Is this suitable for roof and gutter repairs?
  Yes, it is a popular choice for exterior roof patching, gutter sealing and general waterproof maintenance work.

• Is the 5 litre size suitable for trade jobs?
  Yes, the 5 litre trade-size tin is ideal for larger repair work and offers good value for more frequent use or bigger coverage requirements.

(Please note that tins will get dented in transit and this is not a reason for return please do not purchase tined products if this is an issue for yourself.)