Greater London · England
Selsdon Sand Mastic
Sand mastic for Selsdon, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Old cement repairs round a window that have failed
- Gaps round a timber door in stone or brick
- Old sand mastic that has cracked, crumbled or fallen out
Sand mastic for homes and businesses in Selsdon
On many period windows, sand mastic looks right and suits the building. Newer frames normally get a flexible sealant instead, and we’ll talk through which suits your home. We work on brick reveals, sash and case windows and period & listed homes, and the jobs we see most are mastic worn away on windows facing the weather and mastic that needs renewing before redecorating. Mastic man, silicone man or sealant specialist, the name varies; in Selsdon, the job is the same: proper preparation and the right sealant for every joint.
London’s Victorian and Edwardian terraces were built with timber sash windows, and many still have them or their replacements. Whatever is in the opening now, the joint between frame and wall is what keeps the weather out, in Selsdon as anywhere.
A one-year guarantee comes with the work, just as it does everywhere we cover.
- Where
- Selsdon (CR2, CR0)
- Region
- Greater London
- Cover
- One year on every job
- Quote
- A clear price before we start
- Phone
- 07833 053749
- Page updated
- 26 October 2026
How the visit works
The work is kept neat and contained to the joints we are treating, so you can get on with your day. Expect the work to take a few hours per window, depending on the condition of the joints, and we explain the cure time before we leave. In Selsdon, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- We look at the surrounds with you and agree the joints to renew.
- We remove the old, loose mastic.
- Deep gaps are packed so the mastic sits at the right depth.
- The sand mastic is mixed and pressed into the joint by hand.
- We dress the finish so it sits neatly against the masonry.
Getting ready for the visit
- Tell us about any water getting in
- Tell us about any previous sealing or DIY attempts
- On commercial sites, let us know about site rules
Get a quote
Want a quote for sand mastic? Please ring 07833 053749 or email us and tell us about the job. You will know what we plan to do, and what it will cost, before any work begins.
Advice
Work for landlords, hotels and businesses
We regularly work with letting and managing agents. Tell us the address, the job and how access works.
Water getting past a failed joint can damage the building, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance that we can handle for you.
Aftercare tips
After the cure time, these simple habits help:
- Avoid patching sand mastic with silicone
- Ask us before painting near the mastic
- Take care around the mastic when scraping paint
- Check with your local planning authority if your home is listed
Check the mastic when you check the paintwork. Small cracks are easier to deal with early.
Gaps round a sash box let in draughts and rain. Left, the gap tends to get bigger.
Windows and doors in Selsdon
In London conversions and blocks, the lease decides who is responsible for the frames, so check that before you book. Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
For an older house near a landmark such as St Francis, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. Rented homes near Sanderstead station change hands often, and any sash windows need sound mastic to keep draughts and rain out.
Selsdon is about 2 miles south-east of Croydon, in Greater London. Homes, rented property, offices and hotels in Selsdon can book us for sand mastic. Every job comes with our 12-month guarantee. Across Greater London, we cover 786 places, Selsdon among them.
We cover every part of CR2 and CR0 for sand mastic. We cover properties on York Road, Byron Road and Abbey Road and the roads around them. Neighbouring places we cover for sand mastic include Forestdale (1 mile east), Addington (1 mile north-east), Sanderstead (1 mile south-west), Coombe (1 mile north-west) and Farleigh (2 miles south-east). Within a short drive, we also cover London (11 miles north), City of Westminster (12 miles north), Marylebone (13 miles north), Kensington (12 miles north-west), St Pancras (13 miles north) and Shoreditch (13 miles north).
Near you in Selsdon
Typical jobs here are in homes near Royal Russell School, The Sir Julian Huxley pub and The Quest Academy and the streets around them. The nearest railway station is Sanderstead station, about 1.7 miles west of the centre. A little further out are St George's Walk (2.7 miles north-west) and Croydon Airport Visitor Centre (2.9 miles west). For a walk, there’s Duppas Hill and Bramley Bank.
What we’re called out for in Selsdon
Some old mastic was never deep enough. Mastic that’s too thin cracks and drops out, which is why we pack deep voids first and get the depth right.
The problems people generally mention when they call are:
- Gaps where the frame meets the masonry
- Patchy fillers round a sash window
- Silicone on a period window that looks wrong
- Wind and rain getting in round a sash window
Selsdon is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book.
What to look for in a quote
- How the surfaces are prepared before sealing
- Whether they seal over old material or remove it
- What the quote includes, VAT included or not
- How much experience the applicator has
DIY versus a professional finish
A careful DIYer can reseal a simple joint, 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.
If you’ve already had a go yourself, that’s fine. We cut it out and start again, so tell us about it when you ask for a quote.
Why deal with it now?
Draughts round a sash window aren’t always the sashes. Open mastic joints round the box can let air in and new mastic seals them. Converted houses in London often have a bathroom above someone else’s living room, and a slow leak from a failed seal can end up in the flat below. Putting it right early is much less trouble.
Rather than a set price list, we price the job in front of us: the amount of work, the old material and the access. The price is agreed before we begin.
Why choose Mr Mastic in Selsdon
- We’re fully insured
- Every job guaranteed for a year
- Old sealant always removed completely
- We leave the area clean and tidy
Places near Selsdon
More services for Selsdon
What we can’t put right
It helps to know what we cannot do too:
- Putty and glazing repairs
- Timber that has rotted
- Sashes that rattle, stick or won’t open
If in doubt, call 07833 053749 or drop us an email and we will say what we think before booking.
What we seal
- Sash and case windows
- Tenement windows
- Timber door frames
- Period & listed homes
- Stone surrounds
- Brick reveals
Selsdon: your questions answered
Is parking a problem for a job in Selsdon?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. That way the visit can be planned around it.
Do you cover Selsdon for sand mastic?
Yes. We work across London and the South East, and Selsdon is part of that. Just phone 07833 053749 or send us an email with a few details of the job.
Is it possible to take out silicone and use sand mastic instead?
Yes, it’s a common request. The old silicone has to come out completely so the mastic can sit properly.
Is the work guaranteed?
You get our 12-month guarantee on every job.
How long does sand mastic take?
Typically it takes a few hours per window, depending on the condition of the joints. Larger jobs naturally take longer.
Do I have to be there?
For indoor joints, yes, someone needs to let us in. After that, you can carry on with your day.
Are you ARBOMaster approved?
Yes. ARBOMaster is the approved applicator scheme for Arbo sealants, and we’re part of it.
Where are you based?
We’re a Crawley-based firm, with over 20 years’ experience. Our area covers South East England, London and Scotland.