Greater London · England
Window Mastic in Lower Holloway
Mastic around window and door frames, sills and patio doors for Lower Holloway, backed by a 12-month guarantee. Ask us for a quote.
- Rushed sealant from a window installation
- Rain getting in at the frame or under the sill
- Hard, cracked sealant around windows
Window mastic for homes and businesses in Lower Holloway
Behind a thin line of old mastic there’s sometimes a deep void. Filling it with sealant alone leaves a joint that cannot move properly, so we fit backing rod to set the right depth. That way the new bead bonds to the frame and the wall only. We’re often asked to deal with gaps where the sill meets the wall and mastic that has split away from the wall, on uPVC windows, timber windows & doors and patio & French doors.
London homes have every kind of window, from timber sashes in period terraces to aluminium and uPVC in newer blocks. The mastic around them dries out and cracks with age, letting in draughts and water.
Big or small, it’s backed by our 12-month guarantee in Lower Holloway and across Greater London.
- Place
- Lower Holloway (N7, N1, N5)
- Wider area
- Greater London
- Guarantee
- A year, on every job
- Quotes
- A clear price before we start
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Do you need window mastic in Lower Holloway?
A lot of older mastic was never designed to stay flexible. Once it has hardened, the frame’s movement tears it from the wall, leaving a hairline gap down one side.
Most people get in touch when they notice one of these:
- Old mastic that has gone black or come away
- White mastic on grey or black frames
- Draughts coming in around windows and doors
- Damp patches on the reveal after heavy rain
If you look after a building such as Sacred Heart Catholic Primary School, larger buildings have plenty of frames, and the mastic around each one ages.
What your quote should include
- How the colour is chosen
- Whether they seal over old material or remove it
- How hidden problems are handled
- Whether the sealant suits the joint
What happens on the day
There’s no need to move everything out, only the area right around the joints. We protect the rest, and the work takes a few hours for a few frames, or a day or more for a whole house for a typical job. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- First we look at every frame and agree the list.
- Next the failed sealant is cut away and the joint cleaned.
- Deep gaps are filled with backing rod to set the depth.
- We apply a weatherproof sealant to match the frame and tool it neatly.
- We clear up and check every joint is fully closed.
Before we arrive
- Tell us if parking is tricky
- Mention if the joints have been sealed before
- Move anything stored near the joints
Get a quote
If you are in Lower Holloway and need window mastic, call 0345 464 0079 or drop us an email. Tell us what the problem is and where, and we’ll agree the price before any work begins.
Related advice
Windows and doors in Lower Holloway
The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. With historic houses such as Witanhurst (about 2 miles north-west) nearby, there’s older building stock in the area around Lower Holloway as well as newer homes. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window.
As a London address, Lower Holloway can be tricky for parking: let us know about parking bays, permits or a driveway. For landlords with property near Caledonian Road & Barnsbury station, cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets.
Lower Holloway is about 2 miles north of St Pancras, in Greater London. If you need window mastic in Lower Holloway, please phone 0345 464 0079 or email us for a quick quote. We’re based in Crawley and cover Greater London. 764 places in Greater London are on our list, large and small.
Postcode districts we cover here for window mastic: N7, N1 and N5. That includes homes and businesses on Penn Road, Cliff Road and Lough Road. Main roads around Lower Holloway include the A5203. We also cover the places around Lower Holloway: Barnsbury (1 mile south), Holloway (1 mile north), Nag's Head (1 mile north), Tufnell Park (1 mile north-west) and Islington (1 mile south-east). Larger places within reach include London (4 miles south), City of Westminster (3 miles south-west), Marylebone (3 miles south-west), Kensington (5 miles south-west), Walthamstow (5 miles north-east) and Whitechapel (3 miles south-east).
Landmarks near Lower Holloway
Locally, jobs take us to homes and businesses close to St Mary Magdalene Gardens, Musical Theatre Academy and St Mary Magdalene Academy. Also close by are Vaughan Williams Memorial Library (1.6 miles south-west) and The Lamb Tavern Public House (within half a mile west). The nearest railway station is Caledonian Road & Barnsbury station, roughly 0.5 miles south of the centre. Well-known places in the area include Arsenal Football Club Museum (0.6 miles north-east) and Montfichet's Tower (2.6 miles south). Open spaces near Lower Holloway include Dartmouth Park Hill and Barnsbury Wood.
What happens if it’s left?
A cracked joint around a frame lets rain into the wall. Over time that can mean damp patches, damaged plaster and rotting timber. A reseal is a much smaller job. Damp from a failed joint spreads quietly in older London brickwork and timber, and by the time it shows on a wall or ceiling in Lower Holloway, the repair is bigger than the sealant job would have been.
Some things make a job bigger or smaller: how much old sealant there is and how stubborn it is, any mould to treat, and whether the work is at height. We take all of that into account in your quote.
Why Lower Holloway clients choose us
- Approved under the ARBOMaster scheme
- Every job guaranteed for a year
- Any old sealant cut out fully, not covered over
- Sealant colour chosen to suit
Read how sealant jobs are priced and customer reviews.
Quotes for window mastic in Lower Holloway
We quote each job individually. These are the things that affect it:
- The number of rooms or windows
- When we can work, for business premises
- Whether there’s mould to deal with
- The size of the job
There are no prices on our website, because the cost depends so much on the job itself. For a quick quote, please phone 0345 464 0079 or email us and we’ll talk you through it.
What to tell us for a quote
Photos by email are helpful but not essential. Please mention:
- How many joints, rooms or windows are involved
- The problem you’ve noticed
- Any previous sealing or DIY work
- Whether it’s a home or a business
For a quote, phone 0345 464 0079 or drop us an email with the location and a short description of the problem. You will have a clear quote before any work starts.
Your questions about window mastic in Lower Holloway
Do you work for landlords with property near Caledonian Road & Barnsbury station?
Yes. We work for landlords and letting agents as well as homeowners. Just phone 0345 464 0079 or drop us an email with the address and what needs doing, and we’ll send you a clear quote.
Can parking be tricky for a visit in Lower Holloway?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. The visit is then planned around what’s available.
Can you do upstairs windows?
Yes, where it’s safe. For high or awkward windows, we’ll tell you what access is needed.
Do I have to be there?
We need access to the joints, so we’ll agree that with you when we book. For inside work, that normally means someone being in.
Do the sealants smell?
There can be a smell while the sealant cures, which fades as it sets. Ventilation helps.
Where do you work from?
Mr Mastic is based in Crawley. Our applicators cover Lower Holloway, along with the rest of our area.
What should I tell you?
Where the job is, what the problem is and roughly how big it is. Photos by email help too.
Can I add another job to the visit?
Yes. Just list everything you need.
Can I do it myself?
The difference is mostly in the preparation and the product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions, then guaranteed for a year.
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
Also near Lower Holloway
Also in Lower Holloway
Landlord and commercial work in Lower Holloway
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.
Whether it’s one flat or a portfolio, the work is the same standard: the old material taken out, careful preparation and a 12-month guarantee.
Aftercare tips
Good habits help new joints last longer. A few tips:
- Keep solvents and bleach off the sealant
- Keep paint off silicone joints
- Wash the frames with mild soapy water
- Repaint timber before it’s bare
Keep the new mastic undisturbed while it cures, for as long as we advise. Do not point a pressure washer at the joints.
Draughts get worse, not better. As old mastic keeps shrinking, the gap widens, and heat escapes around the frame. A new joint closes it up.