About Mastic Doctor

Commercial sealant applicators since 2005

Mastic Doctor has worked on commercial buildings since 2005. Over those 20-plus years our focus has stayed the same: sealant and mastic joints for businesses and the contractors who build and maintain their premises. We do not take on domestic work. Our clients are main contractors, developers, facilities managers, managing agents and property factors, housing associations, hotels, healthcare and care providers, schools and universities, retailers and shop fitters, restaurants, office occupiers and owners of industrial units and warehouses.

The work itself covers the joints that keep a building weathertight, hygienic and compartmented: facade and window perimeter joints, expansion and movement joints, floor joints, washrooms and kitchens, coloured and colour-matched sealant, and fire-rated sealant at service penetrations where it is specified. See our commercial sealant contractors page for the full range.

Some clients need one washroom resealed; others want a contractor to look after the joints on a whole portfolio. We handle single jobs, multi-site work and planned maintenance programmes, with one point of contact whichever it is. Think of it as a check-up for the building: we find which joints have failed, explain why, and put them right with the correct product.

How we work: diagnose, quote, seal, guarantee

Every job follows four steps.

1. Send details. Drawings, photos, approximate joint lengths, the site address and your programme dates. Where the information is not enough to price accurately, we arrange a site visit.
2. Get a quote. We work out what has failed and why, and price the job as a fixed quote.
3. We seal. Failed sealant is cut out, joint faces are cleaned until sound and dry, primed where the manufacturer specifies it, backed with the right rod or tape and sealed using a product selected to suit the movement, substrate and exposure.
4. Guaranteed. Our workmanship carries a 12-month guarantee.

Tell us your site hours and access windows and we’ll plan around them. Phased work can be planned so areas stay in use, which matters in hotels, hospitals, schools and working warehouses.

Accreditations and insurance

We are CHAS accredited and a Constructionline member, and our applicators hold CSCS cards. We carry £5m public liability insurance. Those are the checks most main contractors and facilities teams ask for before a contractor sets foot on site, and we are happy to supply the details with a quote. Our accreditations page explains what each one means.

Where we work

We cover South East England, Greater London and all of Scotland. In England that means London and the City of London, Kent, Essex, Hertfordshire, Surrey, Berkshire, Buckinghamshire, Oxfordshire, Hampshire with the Isle of Wight, and both Sussex counties. In Scotland we work across every council area, from the central belt cities to Aberdeen, Dundee, the Highlands and the islands. One phone number covers every area: 01277 525 020. See areas we cover.

What we leave to others

Being clear about our scope helps you plan a project properly.

• Fire-stopping design and sign-off belong to your designer, principal designer, fire engineer or building control. We install fire-rated and intumescent sealant following the specification and the product maker’s tested details, and we’ll tell you if a detail calls for a different product.
• Structural glazing is a specialist trade of its own. We seal the perimeter joints where frames meet the structure, not the glazing system itself.
• Access equipment such as scaffold is arranged with the client or main contractor. Tell us what is in place and we’ll price the work on that basis.

Our office is open 8am to 5pm, Monday to Friday. To start, send details through our quote form or call 01277 525 020.