Hertfordshire · England
Sand Mastic in St Nicholas
Sand mastic for St Nicholas and the surrounding area: careful preparation, the right product and tidy work. Call for a quick quote.
- Silicone on a period window that looks wrong
- Draughts and rain around sash boxes
- Gaps between timber frames and stone or brick
Sand mastic in St Nicholas
Old sand mastic cracks, crumbles and falls out over time, leaving gaps round the window. Renewing it closes the gap and tidies the surround. We work on tenement windows, timber door frames and sash and case windows, and people most often call us about gaps round a timber door in stone or brick and tired mastic found when preparing windows for paint.
In smaller places like St Nicholas, homes range from older cottages to newer houses, with windows to match: timber, uPVC and aluminium. The right sealant depends on the frame and on what it sits in.
The work is covered for a year after we finish. If anything is not right with it, phone 0345 464 0079 or send us an email.
- Where
- St Nicholas (SG1, SG2)
- Wider area
- Hertfordshire
- Guarantee
- One year on every job
- Price
- A clear price before work begins
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
What affects the quote in St Nicholas
We don’t publish a price list, because no two jobs are the same. What we look at:
- Whether old sealant or filler has to be cut out
- How many areas need sealing
- Whether there’s mould to deal with
- Working hours on commercial sites
The cost reflects the work involved, not a rough estimate. That is why we ask a few questions first and send you a clear quote before we start.
Asking for a quote
You don’t need to know the technical terms. It helps if you can tell us:
- If it’s domestic, commercial or a hotel
- The problem you’ve noticed
- Where the property is
- How we’d reach the joints
For sand mastic in St Nicholas, phone 0345 464 0079 or send us an email. A short description of the job and where it is helps us quote, and we’ll agree the price before any work begins.
What else we do in St Nicholas
Work for landlords, hotels and businesses
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.
We work for letting agents and landlords as well as homeowners. Resealing between tenancies is a simple way to keep a property in good order.
St Nicholas homes and the weather
Stevenage, which St Nicholas is part of, is one of England’s post-war new towns. With many homes from the post-war decades, replacement windows and doors are common. The mastic around replacement frames ages too, and gaps at sills and frame heads are where water gets in. Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Letting a property close to Stevenage station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about. If you live in an older home near All Saints Church, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
St Nicholas is about 1 mile north of Stevenage, in Hertfordshire. We carry out sand mastic for homes and businesses in St Nicholas, as part of our work across Hertfordshire. We cover 381 towns and villages across Hertfordshire, large and small. We also work in London, around 30 miles away.
Work in SG1 and SG2 is quoted and booked the same way as anywhere else. That includes homes and businesses on York Road, Ripon Road and Drury Lane. We also cover Rooks Nest (1 mile west), Pin Green (1 mile south-west), Chells (1 mile south-east), Stevenage (1 mile south) and Bedwell (1 mile south-west). Within a short drive, we also cover St Albans (14 miles south-west), Bishop's Stortford (15 miles east), Welwyn Garden City (9 miles south), Harpenden (10 miles south-west), Hitchin (4 miles north-west) and Hoddesdon (14 miles south-east).
Near you in St Nicholas
Locally, jobs take us to homes and businesses close to Church of Saint Nicholas and The Nobel School. St Nicholas’s nearest station is Stevenage station, roughly 2 miles south-west of the centre. Nearby you’ll also find Wymondley Castle (2.7 miles north-west) and Stevenage Museum (1.8 miles south-west). Not far away are Pryor's Wood.
Leave it or put it right?
A silicone bead can be quicker, but it can look wrong on a period surround. Sand mastic suits the building and finishes neatly against the masonry. Around St Nicholas, water from a failed joint in an older home can soak into timber and plaster, and that is a much bigger job than renewing the sealant.
What it costs depends on the size of the job, how hard the old material is to remove and access to the work. We give a clear quote before work begins, so you know where you stand.
Why St Nicholas clients choose us
- Trusted Arbo and Everbuild sealants
- More than 20 years in sealant work
- Every job guaranteed for a year
- Fully insured
See our cost guide or our reviews.
What we do, step by step
Every visit runs the same way: we check the joints, mask and protect the surrounding surfaces, carry out the job and clear up. Most jobs take anything from a few hours to a full day, depending on how many windows. Parking around St Nicholas is usually easier than in a town centre, but mention any lanes, gates or long drives. If the job is outside, tell us about side access and how high the joints are.
- Each surround is checked first.
- The joint is raked out and cleaned.
- We fill deep gaps so the new mastic isn’t too thick.
- We point the joint with sand mastic by hand.
- The finish is dressed neatly.
Getting ready for the visit
- Mention any leaks or damp you’ve noticed
- Tell us if parking is tricky
- For business premises, tell us about site rules or sign-in
Getting a quote
Want a quote for sand mastic? Please ring 0345 464 0079 or send us an email with a few details. You’ll know what we plan to do, and what it will cost, before any work begins.
Read more
DIY sealant or a professional job?
Sealing over old silicone is the commonest DIY error. Silicone does not stick to old silicone, 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, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Common problems we fix in St Nicholas
Water gets into small cracks in the mastic and pushes it out. Exposed elevations usually fail first.
Common reasons people contact us are:
- Draughty sash windows at the surround
- Mastic round period door frames that has failed
- Crumbling sand mastic round a window
- Mastic worn away on windows facing the weather
Schools such as The Leys Primary and Nursery School are buildings too, and the mastic around its windows and doors needs looking after like any other building’s.
Before you book anyone
- Are they insured?
- The length of the guarantee
- Whether they seal over old material or remove it
- What happens if the job turns out different
When it is not the sealant
It helps to know what we cannot do too:
- Whether work needs listed building consent
- Crumbling stone or brickwork round the window
- Timber that has rotted
If in doubt, ring 0345 464 0079 or email us and we will say what we think before booking.
Where we work in St Nicholas
- Period & listed homes
- Timber door frames
- Tenement windows
- Brick reveals
- Sash and case windows
- Stone surrounds
FAQs for St Nicholas
Do you work for landlords with property near Stevenage station?
Yes, landlords and agents are among the people we work for, and several properties can go on one quote. Just phone 0345 464 0079 or email us with the address and what needs doing, and we’ll give you a clear price.
Do older homes in St Nicholas need their sealant replacing?
Often, yes: cracked, shrunken or mouldy sealant has done its job. The key is cutting all the old sealant out, as new sealant won’t bond to it.
How much does sand mastic cost in St Nicholas?
It depends on the job, so we quote each one individually. For a quick quote, ring 0345 464 0079 or email us with a short description of the job.
What should I tell you?
Just the basics: the address or postcode, what’s wrong and any access issues. Then ring 0345 464 0079 or drop us an email.
Do you offer different sealant colours?
Yes. White, clear and grey are common, and other colours are available for many products, and we agree the colour with you before we start.
What’s sand mastic made of?
It’s sand mixed with a linseed-oil-based binder for the joint between timber frames and masonry.
Should I try DIY first?
Some simple jobs can be done by a careful DIYer. Most DIY failures come from sealing over old material, wet joints or too much sealant.
How long will you be here?
That depends on how much there is to do, but most jobs take a few hours per window, depending on the condition of the joints. We will tell you when we quote.