0845 077 3839
01142 310 911

Open: Mon - Fri: 9am - 5pm

0 Items View Cart

You have no items in your shopping cart.

Chimney pots, manhole covers, plasterers scrim and more


Available on a number of building supplies

Free delivery for orders over £60 on selected products. (excludes bulky, heavy and fragile items)

  • Next day delivery
  • Saturday delivery
  • AM delivery

We accept the following secure payment options. Collected using 128 bit SSL technology.

SagePay and PayPal Secure SSL Certificates

Product was successfully added to your shopping cart.

Everbuild - 903 Bitumen Trowel Mastic

Delivery Not Included

Availability: In stock

Product Name Price Quantity
£6.30  per item
inc VAT
£12.19  per item
inc VAT
£18.58  per item
inc VAT


Bitumen Trowel Mastic is a trowel applied black heavily filled bituminous compound with added fibres for reinforcement. The product forms a surface skin, but the mass below remains soft to allow for moderate movement. Suitable for sealing and filling holes in mastic asphalt, roofing felt, corrugated iron, metal guttering and downpipes.

Additional Information

Product Code eb.903btm
Quick Find Code 007766
Manufacturer Everbuild
Supplier Colour Black
Container Size Multiple
Usage Instructions

BLACK JACK BITUMEN MASTIC is ready for use and should not be thinned. Apply by steel trowel or putty knife.


  • Force the compound into the crack, but finish with a 25mm band at a 3mm thickness running the length of the crack. 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 to overlap the crack or hole by 50mm. Allow to dry and then apply a second coat, fully covering the reinforcing membrane.



  • Tighten loose hook bolts and trowel around with mastic. Remove loose screws, re-bed screws and washers in BLACK JACK BITUMEN MASTIC and tighten. Top seal in further mastic and trowel to a smooth finish. If the sheet is cracked, clean and prime with BLACK JACK Bitumen/FLASHING Primer and apply a bandage strip of glass fibre embedded in the mastic. When dry, overcoat with BLACK JACK BITUMEN /FLASHING PRIMER followed by BLACK JACK BITUMEN PAINT. Use the same technique for sealing side and end laps in corrugated sheeting.



  • Point up butt edges of ridge tiles, fillets and slates with BLACK JACK BITUMEN MASTIC.



  • Trowel over cracks and pinholes, where necessary, reinforcing with a woven glass membrane, fully embedded and covered.



  • Re-adhere loose felt using BLACK JACK ROOF FELT ADHESIVE. Apply BLACK JACK BITUMEN MASTIC and overcoat with BLACK JACK ALL WEATHER ROOF COATING. Note: felt must be completely dry before applying the mastic.



  • Tools may be cleaned by using white spirit. Spillage’s should be wiped off surfaces before the primer has set.
Country of Manufacture United Kingdom

No reviews available.

The free delivery over £60 does not include certain items, typically this relates to chinmey pots, large items and heavy manhole covers. Whilst we would like to include delivery due to the weight or fragileness we have to send the products via specialist companies to ensure safe and sucessfull delivery to you.

All delivery methods will require someone to accept the delivery, check it over and sign received in good condition. Please note any damages on the delivery sheet / electronic device, do not use the product and contact us straight away.

Next day, AM/PM or even Saturday deliveries can be arranged at an extra cost. Please add your items to the shopping cart for an instant quote.

Pallet Deliveries (Large Items)

After your order has been dispatched you will be contacted on the phone (within 2 days), by your local pallet delivery company in your area, once they receive the goods from our local depot, to book-in a day that is convenient for you. (this will not occur on Timed, Next Day & Saturday deliveries). The delivery will arive on a lorry with an electric tailift and a hand pump truck.

Parcel Deliveries (Smaller Items)

After your order has been dispatched you will receive your goods within 2-3 days. No telephone book-in will occur.

Remember when handling your goods:

  • Take care when removing the packaging / banding and also when removing the product out of the crate / pallet as they may have weakened during transit and could be unstable.
  • Some products are quite heavy and can weigh a lot. Consider this when arranging the delivery, as you may need appropriate lifting equipment, or an extra pair of hands.

To ensure you prepare adequately for pallet deliveries please watch the video below for a comprehensive guide.