Blackline Mastic
London
Checkatrade member since January 2026
Accepts Checkatrade Pay
We guarantee the work for up to £1,000 for 12 months. T&Cs apply
Public liability insurance is unverified
Services
- Mastic Sealant
Customer Reviews
Write a review9.96 /10
Based on 8 reviews over the past 12 months
Quality of work
10
Reliability
10
Communication
9.88
Reviews (8)
10 Shower room, toilet, sink and floor edges resealed
Posted 12 June
Ion was excellent. Kept me fully informed throughout including arrival time and any traffic delays. Polite, courteous and did the job very well indeedVerified reviewerJob location: TW11- RRobert G
10 Had my shower resealed.
Posted 27 March
Punctual, courteous, neat and tidy, and a very professional jobVerified reviewerJob location: DA7 - DDavid J
10 Replacing bathroom sealant
Posted 21 March
Excellent service, I appreciated that they could come on a Saturday. The contractor was friendly and professional and did an excellent and efficient job.Verified reviewerJob location: CR0 9.67 First class tradesman.
Posted 11 March
Job location: E6What I want from a tradesman is that they turn up on time and complete the task as agreed. And this is exactly what BLACKLINE did. Made a couple of small suggestions that I'd missed. Excellent job, definitely recommend Ian.- HHolly Z
10 Very good job resealing shower
Posted 01 March
Very good job on resealing our shower. Good communication, fitted us in at short notice and was flexible, did a great job and was clean and tidy. Thanks Ian!Verified reviewerJob location: E3 10 Great work
Posted 13 February
Job location: E17Very happy with the work completed by Blackline Mastic. The job was carried out to a high standard with a very neat finish. Communication was good from start to finish, they arrived on time, and everything was left clean and tidy. Reliable, professional, and I wouldn’t hesitate to recommend Blackline Mastic to others
Photos
Company Info
Owner
Mr Ion leahu
Sole Trader
Member since 2026
VAT Registered
No
Blackline Mastic – Professional Sealant Specialists
Blackline Mastic provides expert mastic and sealant services across the UK, with over 5 years of experience delivering clean, durable, and professional finishes.
We work on residential, commercial, and industrial projects, using high-quality, mould-resistant sealants to ensure long-lasting results on every job.
Our Services
- Bathroom & shower sealant (leak prevention & mould resistance)
- Kitchen worktops & floors
- Window & door frames (internal & external)
- Expansion joints
- Skirting boards & flooring
- External sealing for buildings and masonry
All work is completed with precision, clean lines, and attention to detail.
Why Choose Blackline Mastic?
✔ Over 5 years’ experience
✔ Reliable, punctual & professional
✔ Premium quality sealants used
✔ Clean, tidy workmanship
✔ Residential, commercial & industrial work
✔ UK-wide coverage
Get in Touch
Whether you need sealant for a new build, renovation, or repair, Blackline Mastic offers a reliable, hassle-free service you can trust.
Blackline Mastic – Quality Sealing, Done Right.
Accreditations and awards
