Greater London · England
Bloomsbury Window Mastic
We cover Bloomsbury for mastic around window and door frames, sills and patio doors. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Water coming in at the bottom corners of a door
- Mastic that has split away from the wall
- Old mastic that has gone black or come away
How it works
Every visit runs the same way: we look at the joints together, protect the area around them, carry out the job and tidy away. It normally takes most of a day for a typical house, less for a few frames. In Bloomsbury, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- We check each frame and agree which ones need doing.
- The old mastic is cut out and the surfaces cleaned back.
- Deep gaps are filled with backing rod to set the depth.
- We apply a weatherproof sealant to match the frame and tool it neatly.
- Every joint is checked before we leave.
Getting ready for the visit
- Keep children and pets away from the work area
- Try not to wet indoor joints just before the visit
- Tell us if parking is tricky
Getting a quote
For a quote, phone 0345 464 0079 or send us an email with the location and a short description of the problem. We’ll give you a clear price before any work starts.
Advice
Window mastic in Bloomsbury
Every window and door frame has a gap around it, and mastic is what closes it. Once that seal fails, wind and rain find the gap. Our applicators cut it out and replace it with a flexible, weatherproof sealant. We work on uPVC windows, window sills and patio & French doors, and the jobs we see most are rain getting in at the frame or under the sill and mastic that has split away from the wall.
Many London homes are flats, with windows high above the street. In a converted house or block, the lease generally says who is responsible for the windows, so it’s worth checking before booking, and access in Bloomsbury is something to talk through when you book.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we will put it right.
- Location
- Bloomsbury (NW1W, W1T, NW1)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quote
- A clear quote up front
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Looking after it afterwards
Simple care keeps the joints in good condition. Our advice:
- Keep timber frames painted
- Keep drainage slots and sill grooves clear
- Keep jet washers away from the mastic
- Paint up to the joint, not over it
On timber frames, keep the paintwork in good order, since wood that gets wet swells and shrinks more. Keep paint off the silicone itself.
Draughts get worse, not better. As the old mastic shrinks further, more air gets through, and a cold room gets colder. Resealing closes it.
Work for landlords, hotels and businesses
Businesses can book us for washrooms, kitchens, offices and more. For commercial premises, we can talk through working times when we quote.
Letting agents and landlords in Bloomsbury can book us as well as householders. Resealing between tenancies keeps a property looking cared for before the next move-in.
What happens if it’s left?
Draughts and leaks do not always mean new windows. If the frames and glass are in good order, resealing the joints is often all that is needed. If we find failed glass units or worn seals, we will tell you. Damp from a failed joint spreads quietly in older London brickwork and timber, and once it shows in Bloomsbury, the repair is bigger than a sealant job.
What it costs depends on how much there is to do, how much old material has to come out and how easy the joints are to reach. We give a clear quote before we start.
What you get with us
- White, clear, grey or another colour, product permitting
- Arbo and Everbuild products
- Old sealant always removed completely
- 180+ five-star Google reviews
Common questions in Bloomsbury
Can parking be tricky for a visit in Bloomsbury?
Parking in Bloomsbury, as in most of London, takes a little planning: a visitor permit or a nearby bay makes the day run more smoothly.
Is Bloomsbury in your area for window mastic?
Yes. Our work covers London and the South East, and Bloomsbury is part of that. You can ring 0345 464 0079 or drop us an email and tell us what needs doing.
Do you have insurance?
Yes, we’re fully insured for every job we do.
Where is Mr Mastic based?
Mr Mastic is based in Crawley. We cover Bloomsbury and the rest of Greater London, along with the rest of our area.
Can you seal the gap between the frame and the plaster indoors?
Yes. Plenty of draughts come through the inside joint as well as the outside, so it can be worth sealing both.
Can I add another job to the visit?
Yes, we can. More than one area can be quoted together.
Can you do upstairs windows?
Yes, as long as they can be reached safely. Let us know about access when you ask for a quote so we can plan the job.
Will new mastic stop draughts?
In many cases. Air often gets in between the frame and the wall, and resealing inside and out closes it.
Frames and glazing around Bloomsbury
With historic houses such as Dr Johnson's House (about 0.9 miles south-east) nearby, there’s older building stock in the area around Bloomsbury as well as newer homes. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic. In London conversions and blocks, the lease decides who is responsible for the frames, so check that before you book.
Managing a site like UCL School of Slavonic and East European Studies? Then the mastic around its windows and doors needs looking after like any other building’s. Rented homes near London Euston station change hands often, and sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. As a London address, Bloomsbury can be tricky for parking: let us know about parking bays, permits or a driveway.
Bloomsbury is about 1 mile north-east of City of Westminster, in Greater London. Jobs in Bloomsbury get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Across Greater London, we cover 764 places, Bloomsbury among them.
Work in NW1W, W1T and NW1 works the same way as everywhere else we cover. That includes homes and businesses on Drury Lane, Euston Road and Duke's Road. With the A401 and A501 close by, Bloomsbury is easy for our applicators to reach. If you’re just outside Bloomsbury, we cover St Pancras (1 mile north-east), Euston (1 mile north-west), Kings Cross (1 mile north), Holborn (1 mile east) and Fitzrovia (1 mile west). We also work in nearby towns such as Kensington (4 miles south-west), Walthamstow (6 miles north-east), Hampstead (3 miles north-west), Ruislip (13 miles west), Brompton (3 miles south-west) and Stockwell (4 miles south).
Local landmarks in Bloomsbury
Locally, jobs take us to homes and businesses close to Lincoln's Inn Fields, Pilsudski Institute of London and St George the Martyr Church of England Primary School, among other places. Other local landmarks include Queens Larder Public House (within half a mile south-east) and Maria Fidelis Catholic School FCJ (0.6 miles north-west). Bloomsbury’s nearest station is London Euston station, roughly 0.6 miles north-west. Other landmarks nearby include Montfichet's Tower (1.2 miles south-east) and National Hospital for Neurology and Neurosurgery (less than half a mile south-east). Open spaces near Bloomsbury include Barnsbury Wood and Ludgate Hill.
DIY sealant or a professional job?
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, and the work is guaranteed for a year.
When it is not the sealant
Sealant isn’t the answer to every problem, and we’ll tell you before we start. Sealant will not put right:
- Misting between the panes of a double-glazed unit (that needs a new unit)
- A sash or casement that won’t close properly
- Worn gaskets, brush seals or a door that has dropped
If in doubt, phone 0345 464 0079 or email us and we will say what we think.
What we seal
- Timber windows & doors
- uPVC windows
- Patio & French doors
- Composite doors
- Aluminium frames
- Window sills
How we quote for window mastic
For a quick quote, just ask. What matters most is:
- Mould in or behind the old joints
- The size of the job
- Any working-time requirements on site
- The product the joint needs
Commercial jobs are quoted on the same basis as homes: the amount of work, how we reach it and what it needs, plus any working-time requirements on site. Call for a quick quote and we’ll explain what it covers.
What to tell us for a quote
To help us quote quickly, please include:
- The address or postcode of the job
- Pictures of the joints, sent by email
- Whether it has been sealed before
- Roughly how big the job is
Want a quote for window mastic? Please phone 0345 464 0079 or email us with a few details. You’ll know what we plan to do, and what it will cost, before any work begins.