Hertfordshire · England
Sand mastic for sash & case windows in Thorley Street, Hertfordshire
Traditional burnt sand mastic around sash and case windows and doors in stone and brick in Thorley Street, with a 12-month guarantee on every job. Call for a quick quote.
- Failed mastic on an exposed elevation
- Window mastic to renew ahead of painting
- Draughts and rain around sash boxes
Sand mastic in Thorley Street, done properly
Our applicators renew the sand mastic around sash and case windows and doors set in stone or brick. The old mastic is raked out, the joint is prepared and new mastic is shaped by hand. If you are dealing with silicone on a period window that looks wrong and draughts and rain around sash boxes, we can put it right, on sash and case windows, timber door frames and period & listed homes alike.
Outdoor sealant needs dry, clean surfaces, so work on frames around Thorley Street is planned for dry weather. Let us know about access to all the frames, upstairs ones included.
You get a one-year guarantee, the same in Thorley Street as everywhere else we work.
- Place
- Thorley Street (CM23)
- Wider area
- Hertfordshire
- Cover
- A year, on every job
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Looking after it afterwards
Looking after new joints is easy, and it makes a real difference:
- Ask us before painting near the mastic
- Go gently near the mastic when preparing windows
- Ask a joiner to look at soft timber first
- Keep modern sealant off the mastic
Make sure water drains away from the window surround. Constant wetting wears the mastic faster.
Sound mastic protects the frame. Once it fails, water can sit against the timber, which can lead to rot.
Nearby places to Thorley Street
Also in Thorley Street
What we are called out for in Thorley Street
Sand mastic slowly weathers. It hardens, cracks and starts to come away from the frame or the masonry.
The most common problems we see are:
- Window mastic to renew ahead of painting
- Weathered mastic on the most exposed windows
- A silicone bead on a sash window that spoils the look
- Mastic round period door frames that has failed
If you look after a building such as Thorley Hill Primary School, its window and door frames need their mastic kept sound, just like a home’s.
What to look for in a quote
- How the surfaces are prepared before sealing
- When the joint can take water or movement
- Who turns up on the day
- What insurance they hold
Landlord and commercial work in Thorley Street
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Keeping joints in good order is simple maintenance.
Letting agents often deal with us directly. Tell us the address, the job and how access works and we’ll quote.
Thorley Street homes and the weather
With historic houses such as Much Hadham Palace (about 3.6 miles west) nearby, there’s older building stock in the area around Thorley Street as well as newer homes. 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.
Homes close to Parish Church of St James the Great include some older properties, and replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint. Letting a property close to Bishops Stortford station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about.
Thorley Street is about 1 mile south of Bishop's Stortford, in Hertfordshire. Every kind of property in Thorley Street is covered for sand mastic. Every job comes with our one-year guarantee. Thorley Street is one of 381 towns and villages in Hertfordshire where we work. For nearby work, see our Chelmsford page (16 miles or so).
Postcode districts we cover here for sand mastic: CM23. We also cover the places around Thorley Street: Thorley (1 mile west), Spellbrook (1 mile south), Little Hallingbury (1 mile south-east), Bishop's Stortford (1 mile north) and Gaston Green (1 mile south-east). Within a short drive, we also cover Stevenage (15 miles west), Hoddesdon (10 miles south-west), Cheshunt (13 miles south-west), Hertford (11 miles west), Ware (8 miles west) and Broxbourne (10 miles south-west).
Local landmarks in Thorley Street
Locally, jobs take us to homes and businesses close to Coach And Horses Public House and The Bishop's Stortford High School, among other places. The closest station to Thorley Street is Bishops Stortford station, roughly 1.2 miles north. Other landmarks nearby include Moated mound (3.4 miles north-west) and Herts and Essex Hospital (1.3 miles north-east). Green spaces nearby include Thorley Wash nature reserve and Portingbury Hills.
DIY sealant or a professional job?
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.
A DIY attempt doesn’t rule out a professional job. We cut it out and start again, so tell us about it when you ask for a quote.
Questions from Thorley Street
Do you work for landlords with property near Bishops Stortford station?
Yes, landlords and agents are among the people we work for. Just ring 0345 464 0079 or send us an email with the address and what needs doing, and we will send you a clear quote.
Can you do sand mastic in Thorley Street?
Yes. Our work covers London and the South East, and Thorley Street is part of that. Just phone 0345 464 0079 or email us with a few details of the job, and we will send you a clear quote.
Do you offer different sealant colours?
We help you choose a colour that suits, from white and clear to greys and other shades. The product needed can limit the range.
Where are you based?
Mr Mastic is based in Crawley. Our applicators cover Thorley Street, along with the rest of our area.
Do you take out the old sealant first?
Yes. Sealing over the old bead is the commonest cause of early failure, and it’s something we never do.
Do you do commercial work?
Yes. We can plan bigger jobs in stages to suit the site.
Do you guarantee sand mastic work?
All our work has a one-year guarantee, and we’re fully insured.
How much does sand mastic cost in Thorley Street?
The cost depends on the size of the job, access and how much old sealant has to come out. Ask us for a quote and we will talk you through it.
What the job involves on each surface
Timber door frames
Period doors in stone or brick openings are often pointed with sand mastic. The method is the same as for windows.
Sash and case windows
The mastic round a sash window is on show, so a neat, even finish matters.
How it works
A visit follows a simple pattern: we look at the joints together, mask and protect the surrounding surfaces, carry out the job and tidy away. Most jobs take a few hours for a single window, longer for several. In a small place like Thorley Street, access is usually the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- First, we look at the surrounds with you and agree what needs doing.
- Old, loose mastic is raked out and the joint cleaned.
- Large voids are packed out first, so the mastic isn’t too thick.
- We mix the sand mastic and apply it by hand, shaping it to the joint.
- We dress the surface so it sits neatly against the masonry.
Before we arrive
- Let us know about parking restrictions
- For business premises, tell us about site rules or sign-in
- Move anything stored near the joints
Ask for a quote
Getting a quote is simple: let us know the job and the location, and roughly how big it is. A few photos by email make the job easier to understand, and we’ll come back to you with a quote.
Read more
How we quote for sand mastic
We don’t publish a price list, because no two jobs are the same. What we look at:
- Whether the work is at height
- The amount of work
- Whether old sealant or filler has to be cut out
- Whether there’s mould to deal with
Combining jobs into one visit generally makes better use of the time than several visits, so it’s worth mentioning everything you’d like done. You will get one clear quote for the whole job.
Asking for a quote
To make quoting easier, let us know:
- Where the property is
- What’s wrong with the joints now
- If it’s domestic, commercial or a hotel
- Pictures of the joints, sent by email
To get a quote, phone 0345 464 0079 or email us and tell us where the job is and what the problem looks like. We’ll give you a clear price before any work starts.