Construction and new-build mastic in Coldharbour, Kent
Mastic packages for new-build and refurbishment projects throughout Coldharbour and nearby, carried out by CSCS-carded applicators. Fully insured and CHAS accredited.
- Sanitary sealant damaged by following trades
- Window and door perimeters that won’t pass inspection
- Old sealant on a refurbishment that needs stripping before new work
Construction mastic for Coldharbour sites
Share the site address and what’s failing, and we’ll reply with a fixed quote or arrange a visit.
On site: what to expect
Site rules come first: sign-in, induction and whatever permit system the building uses. With the paperwork done, we take the joints in the sequence agreed with you. For work around Coldharbour, we aim to finish in one visit, so we ask for photos and rough sizes first. That way the right products come on the day.
- We price from the drawings, specification and programme you send.
- We return a fixed quote that ties the mastic package to your programme.
- You tell us what site paperwork you need, such as RAMS, an insurance certificate or CSCS details, and we confirm it with the quote.
- We seal each plot or floor as it’s released to us.
- Joints are cleaned, primed where the maker requires it, backed and sealed to the specification.
- Before handover, snags are dealt with and the package is signed off under our 12-month guarantee.
Getting the site ready
- Point out any areas we must not close
- Make sure the joints can be reached
- Send your site hours and access windows
Ask for a quote
Tell us about the building, the joints and when you need the work done, and we’ll put a fixed quote together. To get it moving, ring 01277 525 020 or use the quote form.
Advice
How we handle construction mastic in Coldharbour
Getting a subcontractor through site induction should be simple. Our applicators are CSCS-carded, and we’re CHAS accredited and a Constructionline member. Tell us what site paperwork you need (RAMS, insurance certificate, CSCS details) and we will confirm with the quote. We work on brick and block movement joints, window and door perimeters and floor and skirting junctions, and the failures we are asked to look at most are new external sealant already peeling away and bath and shower joints scraped during the final clean. A specialist sealant contractor works differently from a general builder: in Coldharbour, that means joint design, primers and backing rod as standard.
In the countryside around places like Coldharbour, conversion schemes put new frames into old stone, flint, brick or timber. Those joints need a sealant that suits an uneven, sometimes porous surface, and often a colour chosen for the building.
Guaranteed is the last step of every job. You get a 12-month guarantee on our workmanship, and the quote explains what it covers.
- Place
- Coldharbour (TN11)
- Wider area
- Kent
- Cover
- 12 months on our workmanship
- Price
- A fixed quote before we start
- Call
- 01277 525 020
- Last updated
- 3 November 2026
Also near Coldharbour
What else we do in Coldharbour
How the quote is worked out
The price varies from site to site. Expect it to depend on:
- Joint width, depth and condition
- Which sealant the job calls for
- Removal of failed or old sealant
- Site requirements such as inductions and permits
The price depends on how many linear metres there are, what has to come out first and how the joints are reached. Call for a quote when you’re ready.
What to include in your enquiry
A good diagnosis starts with the right details. Tell us:
- Specification clauses that apply
- A wide shot and a close-up of the area
- Access details, including height
- When you need the work done
Send us photographs, drawings or a joint schedule are often enough for a fixed quote. Where a site visit makes more sense, we’ll arrange one.
When it isn’t the sealant
We seal joints; we don’t mend everything behind them. Sealant alone won’t deal with:
- Designing joint widths or choosing the specification (that sits with the designer)
- Approving fire stopping as compliant
- Damage to finishes by other trades after we have sealed
Not sure which it is? You can speak to us on 01277 525 020 or email drawings and photos and we’ll tell you honestly.
Where we work in Coldharbour
- Floor and skirting junctions
- Brick and block movement joints
- Window and door perimeters
- Sanitary and kitchen joints
- Cladding and panel joints
- Internal decorators’ caulk
Site staff or a sealant specialist?
Certain joints really need a specialist: for instance fire-rated seals that must match a tested detail, trafficked floor joints and external movement joints. A poor seal in places like these tends to cost more to put right later.
Redoing a failed joint normally costs more than getting it right at the outset, since all of it has to come out and the faces be cleaned back again. For that reason, many FMs and contractors use a sealant specialist from the outset.
Common questions from Coldharbour clients
Can work at a site such as University of Kent - Tonbridge fit around teaching?
Yes. Tell us the term dates, vacation periods and access windows, and we will plan the work around them. Tell us which site documents you need, such as RAMS, our insurance certificate or CSCS details, and they’re confirmed with the quote.
Is a smaller place like Coldharbour outside your area?
Not at all. Coldharbour is within our area. We work across Greater London and the South East. Send photographs and a list of what needs doing, and we’ll plan the job to need as few trips as possible.
How long does a typical visit take?
We plan the time on site around your programme and access. We’ll give you an estimate of time on site when we quote.
Are you CHAS accredited?
Our applicators hold CSCS cards, and we are CHAS accredited and a Constructionline member. We’re also fully insured, with five million pounds of public liability cover.
Do you do internal caulk as well as external mastic?
External and internal frame perimeters, caulking where it’s specified, sanitary silicone, kitchen joints and snagging before handover. We price to the specification and drawings.
How much does the work cost?
It depends on the job: the volume of work, the access, the specified product and how it’s phased. Call for a fixed quote.
Do you take on mastic snagging only?
Yes. We clear snags by redoing joints rather than patching them to suit the programme.
Sites and facades in and around Coldharbour
Coldharbour sits in one of the drier corners of the country, the South East. Winter mornings still bring frost and condensation on frames and panels, which is why external dates are agreed with the site manager. At about 24 miles from central London, Coldharbour is within reach of the capital. Towns within reach of London tend to keep building, from flats to offices and schools, so mastic packages have to keep pace with busy programmes.
Older buildings in the area around Coldharbour, such as Ightham Mote (2.2 miles north of Coldharbour), need care when sealed: the product has to suit soft or historic materials. University estates such as University of Kent - Tonbridge (to the south of Coldharbour) tend to have a rolling programme of new buildings and refurbishments, each with window perimeters and facade joints to seal.
Coldharbour is about 2 miles north of Tonbridge, in Kent. Anywhere in TN11, the process is the same: send details, get a fixed quote, we seal, and the work is guaranteed. Coldharbour is one of 931 places in Kent on our list. There’s a separate page for London, about 24 miles away.
Anyone looking for construction mastic in TN11 gets the same process as the rest of our area: details, then a fixed price, then sealing and a 12-month guarantee. We also cover Hildenborough (1 mile south-west), Hilden Park (1 mile south), Watt's Cross (1 mile west), Budds (1 mile north) and Stocks Green (2 miles south-west). Nearby towns on our patch include Maidstone (12 miles east), Dartford (15 miles north), Sevenoaks (5 miles north-west), Royal Tunbridge Wells (6 miles south), Gravesend (15 miles north) and Northfleet (15 miles north).
Local landmarks in Coldharbour
In Coldharbour, that means premises near Hugh Christie Technology College and The Flying Dutchman Public House. The nearest railway station is Hildenborough station, about 1.6 miles south-west. Well-known places in the area include Tonbridge Castle (2.2 miles south) and The Milne Museum (2 miles south). Open spaces near Coldharbour include Tudeley Woods RSPB reserve and Barden Lake.
Surface by surface
Fire-rated sealant where specified
Fire-rated sealant forms part of some packages, installed to the product’s tested detail where it is specified. The design and sign-off of fire stopping sit with the designer, principal designer or fire engineer; we work to the specification and the manufacturer’s installation guidance.
Internal decorators’ caulk
Acrylic caulk fills internal gaps around trims, boards and frames ahead of decorating. It’s for gaps that stay still and get painted, and we use a flexible sealant where there’s movement.
Signs you need construction mastic in Coldharbour
Three-sided adhesion is a frequent fault on new work. Fixed to three faces, the sealant rips the first time the joint opens so we set the depth properly before sealing.
Look out for the following:
- Failed sealant in an existing building being refurbished
- Bath and shower joints scraped during the final clean
- Frame gaps too wide for sealant alone
- Snag items on joints that need redoing before handover
When a college such as West Kent College, 2.8 miles south of Coldharbour, builds or refurbishes, the mastic package typically has to fit around students and staff.
Before you book anyone
- Will failed sealant be removed rather than covered?
- Will RAMS and insurance details be available?
- Is depth set with backing rod, or bond-breaker tape in shallow joints?
- Their pre-qualification and accreditations