Kent · England
Sand mastic for sash & case windows in Crayford, Kent
Our applicators work in Crayford on traditional burnt sand mastic around sash and case windows and doors in stone and brick. Old sealant removed completely, joints prepared properly and a 12-month guarantee.
- Patchy fillers round a sash window
- Modern sealant on a period surround
- Gaps where the frame meets the masonry
When to call us in Crayford
Paint, silicone or cement used over old mastic causes problems. They do not suit the joint, and they normally need raking out.
Keep an eye out for these signs:
- Silicone on a period window that looks wrong
- Mastic worn away on windows facing the weather
- Gaps between timber frames and stone or brick
- Gaps round a timber door in stone or brick
If you live in an older home near Church of St Paulinus, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Questions to ask before you book
- How long the guarantee is
- How the joint is cleaned and prepared
- Whether all the old sealant comes out first
- Is VAT in the price?
How we handle sand mastic in Crayford
On many period windows, sand mastic looks right and suits the building. On modern frames we’d normally use a flexible sealant and we’ll explain which is best for yours. We work on sash and case windows, brick reveals and period & listed homes, and people most often call us about modern sealant on a period surround and gaps where the frame meets the masonry.
Houses in smaller places like Crayford can stand more in the open than those in a built-up town. That is hard on the mastic around frames and sills.
Each job carries a 12-month guarantee.
- Where
- Crayford (DA1, DA5, DA7)
- Wider area
- Kent
- Guarantee
- 12 months on all our work
- Quotes
- A clear quote up front
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Looking after it afterwards
Aftercare is simple, and it makes a real difference:
- Ask the planning authority about consent for listed or conservation-area homes
- Avoid heavy scraping on the mastic joint
- Ask a joiner to look at soft timber first
- Ask us before painting near the mastic
Don’t touch or press the mastic while it hardens. It forms a skin fairly soon but needs longer to fully harden.
An open joint round the box lets weather through. The longer it’s left, the more the joint opens.
Should I try it myself first?
The biggest DIY mistake is sealing over old sealant. New silicone won’t bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
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.
How the visit works
Good joint work is mostly preparation, so that is where we spend the time. Every joint is cleaned and dried before new material goes in. In total, it normally takes anything from a few hours to a full day, depending on how many windows. For a job in Crayford, we agree the time, the access and parking before the day. If the work is outside, the weather plays a part, as sealant needs a dry surface.
- We look at the surrounds with you and agree the joints to renew.
- Old mastic and any loose material are raked out.
- Deep gaps are packed so the mastic sits at the right depth.
- We apply the mastic by hand and shape it.
- The surface is finished to suit the stone or brick.
Before we arrive
- Keep children and pets away from the work area
- Move anything stored near the joints
- For indoor joints, keep the area dry beforehand if you can
Ask for a quote
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is, and we’ll explain how we’d tackle it. When it suits you, ring 0345 464 0079 or drop us an email.
Advice
Different surfaces, different methods
Stone surrounds
The stone is treated with care when the old mastic comes out.
Tenement and terrace windows
Rows of sash windows on tenements and terraces often need renewing together. We can do one window or several.
Work for landlords, hotels and businesses
In hotels, rooms out of use cost money, so the work can be planned room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
Failed sealant is one of the commonest items on a check-out report, and it’s quick to put right between tenancies. We can quote for more than one property at once.
Leave it or put it right?
New mastic over crumbling mastic won’t hold. We remove the loose material first so the new work lasts. Homes in smaller places like Crayford can face more weather, and failed outside joints let damp into walls. Indoors, a failed seal lets water into floors and panels as it would anywhere.
Rather than a set price list, we look at what your job involves: the amount of work, the old material and the access. The price is agreed before we begin.
Why us?
- Sanitary silicone with an anti-fungal additive in wet areas
- Old sealant always removed completely
- Neat joints and a tidy finish
- More than 20 years in sealant work
Take a look at how sealant jobs are priced and what customers say.
Your questions about sand mastic in Crayford
Do you cover Crayford for sand mastic?
Yes, Crayford is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or drop us an email and let us know what needs doing, and we’ll give you a clear price.
Can you help a landlord with a rental near Crayford station?
Yes. We work for letting agents and landlords as well as homeowners, and several properties can go on one quote. Just call 0345 464 0079 or email us with the address and what needs doing, and we’ll send you a clear quote.
How long does the job take?
Most jobs take anything from a few hours to a full day, depending on how many windows, including the preparation. Your quote will say how long we expect yours to take.
Will you leave a mess?
Very little: the area around the joints is protected first, and we clear up the old sealant and our materials before we leave.
Should I use sand mastic or silicone?
We will help you decide. Period homes often look best with sand mastic and newer frames suit modern sealant.
How long does sand mastic take to go off?
A skin forms quite soon, but full hardening takes longer. We will explain what to expect before we leave.
Can you quote for more than one area?
Yes. More than one area can go on one quote.
What sealant do you use?
Products from Arbo and Everbuild, among others, picked for each joint. We will tell you what we are using and why.
What sand mastic looks like in Crayford
Historic houses like Hall Place and Gardens (about 0.9 miles west) are a reminder that the area around Crayford has older buildings as well as new. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window. Rainfall in the South East is lower than in much of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
For site and facilities teams at buildings such as Wentworth Primary School, larger buildings have plenty of frames, and the mastic around each one ages. Letting a property close to Crayford station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about.
Crayford is about 2 miles west of Dartford, in Kent. Whether you’re in the middle of Crayford or further out, sand mastic is available for homes and businesses alike, from flats and houses to offices and hotels. Crayford is one of 922 towns and villages in Kent where we work. There’s also a page for London, roughly 12 miles from Crayford.
Our applicators cover all of the DA1, DA5 and DA7 postcode area for sand mastic. If you need sand mastic at a property on Swan Lane, Dale Road and Ross Road or anywhere close by, our applicators can take on the job. Close by, we work in Bowmans (1 mile south), Barnes Cray (1 mile north-east), Barnehurst (1 mile north-west), Coldblow (1 mile south-west) and Wilmington (1 mile south). Further out, we also cover Sevenoaks (12 miles south), Gravesend (9 miles east), Northfleet (7 miles east), Swanley (4 miles south), Swanscombe (5 miles east) and Windmill Hill (8 miles east).
Around Crayford
We work in homes and buildings around Haberdashers' Aske's Crayford Academy, The Bear and Ragged Staff pub and St Catherine's Catholic School and the streets around them. Crayford has its own railway station: Crayford station. Other landmarks nearby include Bexley Museum (0.9 miles west) and West Hill Hospital (1.3 miles east). Green spaces nearby include Wansunt Pit.