Greater London · England
New Build Mastic in Agar Town
New build mastic in Agar Town from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Cracked sealant around new window and door frames
- Cracks appearing as a new home settles
- Sealant that never bonded to the surface
What affects the quote in Agar Town
The quote reflects the job in front of us. We look at:
- The old material and how stubborn it is
- Any mould that needs treating
- How many areas need sealing
- Any working-time requirements on site
The cost reflects the work involved, not guesswork. That is why we ask a few questions first and send you a clear quote before we start.
Helping us quote
A few details help us give you an accurate quote. When you ask for a quote, tell us:
- How we’d reach the joints
- If it’s domestic, commercial or a hotel
- Any previous sealing or DIY work
- What the problem is, such as mould, gaps, leaks or cracking
Asking for a quote is easy: let us know the job and the location and its rough size. A few photos by email make the job easier to understand.
About our new build mastic in Agar Town
New homes move as they dry out. Timber dries and shrinks, and baths and trays settle, so sealant that was laid quickly before handover often cracks. Typical jobs include cracked sealant around new window and door frames and cracks appearing as a new home settles, on kitchens, skirting & floors and windows & doors.
Much of London’s new housing is flats in larger developments. In a new development, snags are often reported through the developer or the managing agent, and shower seals that fail early, skirting joints that open up and gaps at thresholds are all common snags.
You’re covered for a year from the day we finish. If there’s a problem with it, please ring 0345 464 0079 or drop us an email.
- Location
- Agar Town (NW1W, NW1, N1)
- Wider area
- Greater London
- Cover
- A year, on every job
- Price
- A clear price before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Leave it or put it right?
DIY kits don’t solve the main problems with new-build sealant: dust, no primer and old sealant left in the joint. Cutting out, cleaning and priming are what make the difference. In a London flat, a failed joint rarely stays your problem alone: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
Some things make a job bigger or smaller: the old material and how easily it comes out, whether mould needs treating, and whether we need extra access for height. Your quote takes all of that into account.
Why book with us
- Quality sealants from Arbo and Everbuild
- Homes, businesses and hotels
- Anti-fungal silicone where joints get wet
- Approved under the ARBOMaster scheme
Take a look at what affects the cost or what customers say.
Honest limits
It helps to know what we cannot do:
- Settlement cracks that need a surveyor
- Disputes or warranty claims with your builder
- A tray or bath that is not properly supported, until it’s fixed
Not sure which it is? You can phone 0345 464 0079 or email us and we will tell you honestly.
What we seal
- Bathrooms & en suites
- Kitchens
- Skirting & floors
- Show homes
- Windows & doors
- Plot handovers
Should I try it myself first?
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
How it works
We bring everything the job needs with us, so there’s nothing for you to buy. Once we’ve agreed what’s being done, we protect the area and start. It normally takes a few hours in a single home. For a job in Agar Town, parking and access are the things to plan: tell us about permits, visitor bays or off-street space, which floor we’re working on and whether there’s a lift.
- We look at why each joint failed, including any movement.
- Old sealant is cut out and the joints cleaned.
- Joints are dried and primed where the product calls for it.
- Baths are filled with water, then the new sealant is applied.
- We check every joint and leave you with the cure times.
Before we arrive
- For business premises, tell us about site rules or sign-in
- Tell us if parking is tricky
- Plan for the work area to be out of bounds to pets and children
Ask for a quote
For new build mastic in Agar Town, ring 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and we will agree the price before any work begins.
Advice
Agar Town: your questions answered
Can you help a landlord with a rental near Camden Road station?
Yes, we work for landlords and agents. Just ring 0345 464 0079 or send us an email and tell us about the property, and we will send you a clear quote.
Is Agar Town in your area for new build mastic?
Yes. We work across London and the South East, and Agar Town is part of that. Just phone 0345 464 0079 or send us an email with a few details of the job, and we will give you a clear quote.
Do you work through snagging lists?
Yes. Photos of each sealant item help us quote. Items that need a plumber, tiler or the builder are flagged.
Do you remove the old sealant?
Yes. We cut out all the old sealant and clean the joint before applying anything new.
Do you use white or clear sealant?
The colour is chosen to suit the tiles, worktop or frame. Let us know your preference when you ask for a quote.
When is the best time to reseal in a new build?
If the seal has failed and water is getting in, do it now. Hairline cosmetic gaps can wait until the house has settled.
Are you an approved applicator?
Yes. Mr Mastic is an ARBOMaster approved applicator, and we are fully insured.
Why does sealant fail so quickly in new builds?
There are generally two causes: movement as the house dries and settles, and sealant laid onto dust without primer. A proper reseal deals with both.
When to call us in Agar Town
On many sites, sealant goes on in the final rush before handover. Dusty, unprimed joints are common, so the bead never bonds properly.
Keep an eye out for these signs:
- Second-fix sealing on new plots
- Cracked caulk along new skirting
- Gaps behind new kitchen upstands
- Sealant that never bonded to the surface
Agar Town is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
What to look for in a quote
- What the cure time is
- What happens if the job turns out different
- What insurance they hold
- Who does the work, and how experienced they are
How to look after the new joints
Joint life depends on how it’s used and looked after. We suggest:
- Avoid scourers and strong chemicals on sealant
- Do not wait for the house to settle if water is getting through
- Avoid running a DIY bead over the old one
- Photograph failed sealant before it’s redone
Ventilation matters in a new home, which is still drying out. Use the extractor fan or open a window after showers to help keep mould away.
Leave a failed new-build seal and water can reach the floor and the ceiling below. Catching it early keeps the fix to the sealant and the new finishes intact.
Nearby places to Agar Town
Also in Agar Town
Joints and finishes in Agar Town homes
Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. Much of London’s new housing is flats in larger developments, where snagging may go through the developer or managing agent.
For new homes near Camden Road station, it’s worth checking the sealant early, while snags are still fresh.
Agar Town is about 1 mile north-west of St Pancras, in Greater London. Jobs in Agar Town get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. We cover 764 towns and villages across Greater London, from the larger towns to small villages.
Jobs for new build mastic in NW1W, NW1 and N1 is quoted and booked the same way as anywhere else. That includes homes and businesses on Water Lane, Maiden Lane and Camden Road. Being close to the A400 and A5200, Agar Town is simple for us to get to. Neighbouring places we cover for new build mastic include Camden Town (1 mile west), Somers Town (1 mile south), Kings Cross (1 mile south-east), Kentish Town (1 mile north-west) and Barnsbury (1 mile north-east). Larger places within reach include London (3 miles south-east), Kensington (4 miles south-west), Walthamstow (6 miles north-east), Whitechapel (3 miles south-east), Ruislip (12 miles west) and Brompton (3 miles south-west).
Near you in Agar Town
Typical jobs here are in homes near Vaughan Williams Memorial Library, Golden Lion pub and North Bridge House School, among other places. Also close by are Regent High School (less than half a mile south) and Lewis Cubitt Park (within half a mile east). Agar Town has its own railway station: Camden Road station. Nearby you will also find St Pancras Hospital (under half a mile south) and Montfichet's Tower (2.2 miles south-east). Not far away are Barnsbury Wood and St. James's Park Lake.