Kent · England
Sand mastic for sash & case windows in St Lawrence, Kent
Sand mastic in St Lawrence from a team with over 20 years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Gaps round a timber door in stone or brick
- Patchy fillers round a sash window
- Weathered mastic on the most exposed windows
St Lawrence: your questions answered
Do you cover smaller places like St Lawrence?
Yes, St Lawrence is covered. We work across London and the South East, from towns to the smallest places. The journey is planned ahead, so it helps to know about access.
Can you help a landlord with a rental near Ramsgate station?
Yes, we work for landlords and agents. Just ring 0345 464 0079 or drop us an email and tell us about the property, and we will give you a clear quote.
Will you leave a mess?
Tidy work is part of the job. Nearby surfaces are protected, and the area is left clean when we finish.
Do you do commercial work?
Yes. We work in offices, washrooms, hotels and other commercial premises. Working times can be discussed when we quote.
Is it possible to take out silicone and use sand mastic instead?
Usually, yes. Once the silicone is out and the joint prepared, sand mastic is applied by hand.
How long does the job take?
Most jobs take a few hours for a single window, longer for several. Your quote will say how long we expect yours to take.
Can you match the sealant colour?
Normally, yes. Sealants come in white, clear, grey and other colours, and we agree the colour with you before any work starts.
Which is right for my windows, sand mastic or modern sealant?
We will talk it through with you. Sand mastic suits many period homes, and modern sealants suit newer frames.
Sand mastic in St Lawrence, done properly
Sand mastic does not last for ever and gaps open up round the frame. Renewing it closes the gap so the surround looks right again. We work on stone surrounds, sash and case windows and period & listed homes, and people most often call us about mastic dropping out of the joint and tired mastic found when preparing windows for paint.
Many houses in smaller places like St Lawrence have conservatories, garden rooms or patio doors. Those joints need the same attention as the main windows, and any older timber or sash windows need a sealant that suits them.
The work is covered for a year after we finish. If there’s a problem with it, please phone 0345 464 0079 or drop us an email.
- Place
- St Lawrence (CT11, CT12)
- Region
- Kent
- Guarantee
- 12 months on all our work
- Quotes
- A clear price before work begins
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Work for landlords, hotels and businesses
Housing providers, facilities teams and property managers book us too. We can quote a run of properties together.
Letting agents often deal with us directly. Tell us the address, the job and how access works and we will give you a quote.
Surface by surface
Sash and case windows
On a sash window, the mastic joint shows on the outside so we finish it carefully.
Brick reveals
An open joint at a brick reveal lets weather in. New mastic seals the gap.
What sealant work cannot fix
In fairness, there are a few things sealant won’t fix:
- Sashes that rattle, stick or won’t open
- Rotten sashes, sills or window boxes (a joiner’s job)
- Whether work needs listed building consent
If you are not sure, just ring 0345 464 0079 or email us and we will give you a straight answer before booking.
Where we work in St Lawrence
- Stone surrounds
- Sash and case windows
- Timber door frames
- Brick reveals
- Period & listed homes
- Tenement windows
What sand mastic looks like in St Lawrence
St Lawrence is within about 1 mile of the coast, and homes near the sea take more wind-driven rain, with salt in the air closer to the shore. That’s hard on the mastic around older windows and doors, especially on the side facing the sea. Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
If you look after a building such as Ellington Infant School, the mastic around its windows and doors needs looking after like any other building’s. For landlords with property near Ramsgate station, any sash windows need sound mastic to keep draughts and rain out. In the older streets around Church of St Laurence, the joint between an old wall and a newer frame is generally the first place rain gets in.
St Lawrence is about 1 mile west of Ramsgate, in Kent. If you need sand mastic in St Lawrence, it’s easy to get a quote: please ring 0345 464 0079 or email us. We cover Kent from our Crawley base, St Lawrence included. 922 places in Kent are on our list, from the larger towns to small villages. Our Chelmsford page covers work nearby (48 miles or so).
All of CT11 and CT12 is within our area for sand mastic. Whether your property is on Park Road, Saxon Road and Downs Road or anywhere close by, we can help. Being close to the A255, St Lawrence is easy for our applicators to reach. If you’re just outside St Lawrence, we cover Ramsgate (1 mile east), Northwood (1 mile north), Upton (2 miles north-east), St Peter's (2 miles north) and Broadstairs (2 miles north-east). Further out, we also cover Canterbury (14 miles west), Margate (3 miles north), Dover (14 miles south), Deal (8 miles south), Herne Bay (12 miles west) and Tower Hamlets (15 miles south).
Local landmarks in St Lawrence
Around St Lawrence, our work takes us to homes and buildings near Chatham House Grammar School, Churchill House School With Railed Area and The Admiral Fox pub, among other places. St Lawrence has its own railway station: Ramsgate station. Other landmarks nearby include Westwood Cross (1.5 miles north) and Ramsgate General Hospital (0.6 miles south-east). Open spaces near St Lawrence include Sandwich and Pegwell Bay.
What we do, step by step
Before we leave, we go over the finished joints with you. The visit itself generally takes a few hours per window, depending on the condition of the joints, depending on how much there is to do. Parking around St Lawrence is usually easier than in a town centre, but mention any lanes, gates or long drives. For outside work, side access and the height of the joints help us plan.
- Each surround is checked first.
- The joint is raked out and cleaned.
- We fill deep gaps so the new mastic isn’t too thick.
- New sand mastic is applied and shaped by hand.
- We finish the mastic to a tidy line.
How to prepare
- Tell us about access, such as stairs, a lift or high-level joints
- Mention any sign-in or site rules at work premises
- Let us know about earlier repairs to the joints
How to get a quote
For a quote, ring 0345 464 0079 or email us and tell us where the job is and what the problem looks like. You’ll have a clear quote before work begins.
Related advice
Why act early in St Lawrence
Gaps round a sash window let in rain and draughts. Left, water can reach the timber and the wall so renewing it early protects the window. Around St Lawrence, water from a failed joint in an older home can soak into timber and plaster, and that’s a much bigger job than renewing the sealant.
Doing several joints on one visit is usually more efficient than separate visits, so it’s worth mentioning everything you’d like done. You’ll get one clear quote for the whole job.
Why choose Mr Mastic in St Lawrence
- Approved under the ARBOMaster scheme
- Anti-fungal silicone where joints get wet
- Fully insured
- Quality sealants from Arbo and Everbuild
Looking after it afterwards
Joint life depends on how it’s used and looked after. We suggest:
- Keep sills and gutters clear so water drains away
- Leave the new mastic unpainted
- Keep modern sealant off the mastic
- Avoid heavy scraping on the mastic joint
Do not run silicone over the new mastic. If anything cracks, get it looked at rather than patching it.
It’s best to renew mastic before painting the windows. Paint over cracked mastic only covers it up.
DIY sealant or a professional job?
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. All the old material has to come out first.
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, and the work is guaranteed for a year.