The Mastic Doctor team standing beside their branded vans outside an office building
Kent · England

Washroom Sealing contractors in Knockholt

Washroom sealing for Knockholt, from a contractor working since 2005. Fully insured and CHAS accredited.

  • Mould spotting along silicone joints
  • Complaints from staff, guests or users about tired washrooms
  • Shower tray joints that have opened up
1
Send details
Send the specification, photos or a marked-up plan.
2
Get a quote
One fixed quote covering the agreed scope.
3
We seal
The right sealant, to the right depth, neatly finished.
4
Guaranteed
Backed by a 12-month workmanship guarantee.
Covering the South East & Scotland
CHAS & Constructionline
£5m PL insurance

Need washroom sealing in Knockholt?

Share the site address and what’s failing, and we’ll reply with a fixed quote or arrange a visit.

From enquiry to sign-off

In a busy building, the work is phased so only one area is out of use at a time. Each section is protected, cleaned back and sealed before the next one starts. Jobs in and around smaller places like Knockholt are typically planned as a single visit, so photographs and measurements up front really help. Then the right materials arrive with us.

  1. We start by inspecting the fittings and joints and flagging problems sealant can’t solve.
  2. A phasing plan keeps part of the building’s facilities in use at all times.
  3. We strip out the old bead and clean off the residue left behind.
  4. Joints are cleaned, degreased and dried before sealing.
  5. We lay a sanitary silicone bead and tool it smooth so it is easy to clean.
  6. Each room is handed back once the sealant has had its cure time.

Before we start on site

  • Point out parking and an unloading spot
  • Clear stock, furniture or equipment away from the joints
  • Flag any permit to work we will need

Request a quote

The quickest route to a quote is a few photographs and the site postcode. Send them through the quote form, or call the office on 01277 525 020 or email drawings and photos to discuss it first.

Ask for a quote

Related advice

Washroom sealing in Knockholt, done properly

We reseal washrooms and wet areas in offices, hotels, schools, universities, gyms, healthcare buildings and care homes, plus the kitchens and tea points that go with them. The products and the method are chosen for how heavily each space is used. If you are dealing with discoloured joints around urinals and WC pans and split or peeling sealant at shower trays, we can put it right, on kitchens and tea points, accessible toilets and changing rooms and showers, trays and wet room floors alike. One point of contact handles commercial sealant work in Knockholt from the first photos to the final walk-round, for single jobs and planned programmes alike.

Rural businesses near smaller places such as Knockholt, from cafés to event venues, rely on washrooms and kitchens that stay clean. Tell us your opening times and quiet periods and we’ll plan around them.

We sign every job off with a 12-month guarantee. The promise is simple: if the work we did fails within twelve months, we return to fix it.

The Mastic Doctor team beside their liveried vans in front of an office building
Location
Knockholt (TN14)
Region
Kent
Cover
12 months on our workmanship
Quote
Fixed quote, scope in writing
Call
01277 525 020
Updated
3 November 2026

Common questions from Knockholt clients

Must every washroom in our Knockholt building shut while you work?

Not all at once. We take one block of facilities at a time. Each area is handed back once the sealant has cured enough to use.

Is Knockholt too small for you to travel to?

Not at all. Knockholt is within our area. Our area covers London and the South East counties. Good photos up front let us bring everything on the first visit.

Is colour matching possible?

Often, yes. Sealants are made in a wide range of standard colours, and matching to RAL references or nearby finishes is commonly requested. We confirm what’s available for the specified product when we quote.

How long does a typical visit take?

It depends on the scope, though a typical visit typically takes a few hours for one toilet block, with bigger buildings phased across a number of visits. For bigger or phased jobs, we will set out a timescale with the quote.

Which silicone is right for commercial washrooms?

Sanitary silicone with anti-mould additives in the majority of cases. Neutral-cure grades are used where acetoxy types could mark metals, stone or mirror backings.

Do you take on small jobs?

Whatever the size, the process is the same: send details, get a fixed quote, we seal, guaranteed.

When is resealing likely to be due?

There’s no fixed lifespan: movement, exposure, cleaning, traffic and the product all play a part. Sealant joints are maintenance items, so inspect them regularly.

Doing it in-house

Using site staff can make sense for a small touch-up, but larger jobs are different: a specialist works through quantities efficiently, leaves a consistent finish and backs it with a 12-month guarantee.

Paperwork matters too. Many sites expect CSCS cards, RAMS and proof of insurance, and our CSCS-carded applicators are used to working under those rules.

When it isn’t the sealant

Honesty saves time and money. New sealant won’t cure:

  • Mould caused by poor ventilation, which will return until the extract is fixed
  • Hollow tiles or loose panels behind the joint
  • Leaks through tanking or membranes below the finishes

If you are not sure, just phone 01277 525 020 or email the details over and we’ll give you a straight answer.

Joints and surfaces we work on

  • Kitchens and tea points
  • Vanity units and basins
  • Accessible toilets and changing rooms
  • Urinals and WCs
  • IPS panels and cubicles
  • Showers, trays and wet room floors

Owners, agents and contractors

Hotels, schools, healthcare sites, offices and retail units come to us directly as well. We plan around the way the building is used, so the building keeps working while we do.

Facilities managers want contractors who arrive with the paperwork sorted. Let us know the documents you need (RAMS, insurance certificate, CSCS details) and we will confirm them with the quote.

Do you need washroom sealing in Knockholt?

Occasionally a joint keeps failing because of a problem behind it: a loose panel, a leaking waste or water coming through the wall. We look for it before resealing and tell you if another trade is needed.

These are often picked up first by site or facilities staff:

  • Split or peeling sealant at shower trays
  • Gaps where vanity tops meet the wall
  • Stained or open joints at kitchen sinks and worktops
  • Washrooms that look worn because of the sealant

If you manage an office at a site such as North Downs Business Park (2.2 miles east of Knockholt), the washrooms and tea points can be done a floor at a time.

Comparing quotes

  • Their pre-qualification and accreditations
  • How the joint faces will be prepared and primed
  • How the existing material will be dealt with
  • How joint depth will be controlled

Questions to ask before you appoint anyone

Why deal with it now?

Bleaching black sealant may lighten it for a few days, but the mould is rooted in the silicone and comes back. A full reseal deals with it and cleaners stop fighting a losing battle. For buildings around smaller places like Knockholt, water damage can go unnoticed for longer, especially where a building isn’t used daily, so a failed joint can leak for a while before anyone sees it. Resealing early avoids that.

Quantities, awkward access and phased working all shape the price. Site requirements like inductions and permits play a part as well, along with the time of year for external work.

What you get with us

  • Commercial sealant work since 2005
  • One number for every site we cover
  • Colours chosen to suit frames, cladding or finishes where possible
  • Old sealant cut out, never sealed over

Read what affects the cost or how we’re accredited.

Keeping Knockholt washrooms open while we work

At about 16 miles from central London, Knockholt is within reach of the capital, in a commuter belt where offices and business parks are common. Washrooms in commuter-belt offices take constant weekday traffic, and resealing in phases keeps facilities available.

Healthcare estates like Orpington Hospital, 3.6 miles north of Knockholt, expect contractors to follow their permits and cleaning rules in every washroom. Where you’re responsible for a hall attached to a building such as St Katharine's Church, its kitchen and toilets need sealant that stays cleanable.

Knockholt is about 4 miles north-west of Sevenoaks, in Kent. We cover commercial sites throughout Knockholt. Our Kent coverage takes in 931 places. London is covered too, some 16 miles away.

We take on washrooms and wet areas across the TN14 postcode area, whatever the building. Buildings on Main Road and Blueberry Lane are within our area for washrooms and wet areas. We also cover Knockholt Pound (1 mile north-east), Halstead (2 miles north-east), Sepham Heath (2 miles north-east), Pratt's Bottom (2 miles north) and Twitton (3 miles east) for washrooms and wet areas. A short drive away, we cover Dartford (11 miles north-east), Sevenoaks (4 miles south-east), Royal Tunbridge Wells (14 miles south-east), Gravesend (14 miles north-east), Tonbridge (11 miles south-east) and Northfleet (13 miles north-east).

Local landmarks in Knockholt

Locally, jobs take us to sites close to The Three Horseshoes pub. For rail, the closest station is Knockholt station, roughly 2.7 miles north-east. Other landmarks nearby include Orpington Hospital (3.6 miles north) and Otford Heritage Centre (3.9 miles east). Not far away are Betsom's Hill and Downe Bank.

Map of Knockholt © OpenStreetMap contributors
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