Hertfordshire · England
Window Mastic in Radwell
Mastic around window and door frames, sills and patio doors for homes and businesses in Radwell and across Hertfordshire. Fully insured, ARBOMaster approved and guaranteed for a year.
- Hard, cracked sealant around windows
- Rain getting in at the frame or under the sill
- Gaps where the sill meets the wall
Why act early in Radwell
Draughts and leaks do not always mean new windows. If the frames and glass are in good order, resealing the joints is often all that’s needed. Problems with the glass or gaskets are for a window company, and we will say so. In a small place like Radwell, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
Combining jobs into one visit is generally more efficient than separate visits, so it’s worth mentioning everything you’d like done. We’ll give you a clear quote for the lot.
What you get with us
- You choose the colour before work begins
- 4.9 on Google from 180+ five-star reviews
- Sealant colour chosen to suit
- Every job guaranteed for a year
Take a look at our cost guide and our reviews.
Window mastic for homes and businesses in Radwell
The new joint does not have to be white. White, brown, anthracite grey, black and clear sealants are all available, so the bead blends with the window rather than framing it. If you are dealing with a bead that doesn’t match the frame and untidy mastic left by window fitters, we can put it right, whatever the surface.
Outdoor sealant needs dry, clean surfaces, so work on frames around Radwell is planned for dry weather. Let us know about access to all the frames, upstairs ones included.
Whatever the size of the job, it’s backed by our one-year guarantee.
- Where
- Radwell (SG7)
- Region
- Hertfordshire
- Guarantee
- One year on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Also near Radwell
Other services in Radwell
What we’re called out for in Radwell
Plenty of failed mastic was poorly applied in the first place. Sealant run over dust, wet brick or loose mortar didn’t grip properly, and it lets go sooner than it should.
Common reasons people contact us are:
- Black, perished sealant on frames
- Untidy mastic left by window fitters
- Water coming in at the bottom corners of a door
- Draughts coming in around windows and doors
For an older house near a landmark such as Church of All Saints, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint.
What your quote should include
- How hidden problems are handled
- How long to leave it before use
- What insurance they hold
- Is the old sealant removed completely?
What happens on the day
The work is kept neat and contained to the joints we’re treating, so you can get on with your day. The job usually takes a few hours for a handful of frames, longer for a whole house, and we tell you how long to leave it before we go. For a village or hamlet like Radwell, the journey is planned in advance: tell us about narrow lanes, gates, long drives and where we can park. We bring what the job needs, so it can be finished in one trip where possible.
- We check how each frame can be reached safely.
- All the failed sealant is cut away, along with any loose debris.
- Frame and wall are cleaned and must be dry before sealing.
- Backing rod fills deep voids and the sealant goes in on top.
- The joint is shaped to shed water and the area tidied.
Preparing for the visit
- Plan for the work area to be out of bounds to pets and children
- Mention any sign-in or site rules at work premises
- Clear the area around the work
Ask for a quote
To get a quote, call 0345 464 0079 or drop us an email and tell us where the job is and what the problem looks like. We will give you a clear quote before any work starts.
Read more
DIY sealant or a professional job?
Some sealant jobs are within reach of a careful DIYer, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
If you do try it yourself, take your time over the preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it does not work out, we can still put it right.
Windows and doors in Radwell
Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. With historic houses such as Hinxworth Place (about 2.4 miles north) nearby, there’s older building stock in the area around Radwell as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
Managing a site like Norton St Nicholas CofE (VA) Primary School? Then its window and door frames need their mastic kept sound, just like a home’s. For landlords with property near Baldock station, sound mastic around windows and doors keeps out the draughts and damp that tenants notice first.
Radwell is about 2 miles north of Letchworth, in Hertfordshire. Jobs in Radwell get the same care as everywhere else we work: old sealant removed completely, careful preparation and a one-year guarantee. We cover 381 towns and villages across Hertfordshire, large and small. There’s also a page for London, about 35 miles away.
Postcode districts we cover here for window mastic: SG7. Streets in the area include Radwell Lane and The Limes, and we cover them all. Close by, we work in Stotfold (1 mile west), Stotfold Common (2 miles north-west), Fairfield (2 miles west) and Astwick (2 miles north-west). Further out, we also cover Stevenage (7 miles south), Welwyn Garden City (14 miles south), Harpenden (15 miles south-west), Hitchin (5 miles south-west), Hertford (15 miles south) and Ware (15 miles south-east).
Around Radwell
Locally, jobs take us to homes and businesses close to The Knights Templar School, Norton School and The Chequers Public House, among other places. The closest station to Radwell is Baldock station, roughly 1.2 miles south-east of the centre. Other landmarks nearby include Bygrave House (2 miles east) and Fairfield Hospital (1.9 miles west). Green spaces nearby include Arlesey Old Moat and Glebe Meadows.
Aftercare tips
A little care helps the new joints last. Our advice:
- Make sure the drainage slots are not blocked
- Use gentle cleaners on frames and sealant
- Keep paint off silicone joints
- Don’t use solvent cleaners on the joint
A yearly look round the frames is enough. Small splits are simple to catch before they leak.
Wet, windy weather is when failed mastic shows itself, but resealing works best in dry conditions. Dealing with it when you first notice a crack avoids chasing leaks through the wet months.
What the job involves on each surface
Aluminium frames
Metal frames expand in the sun and are often slim, with little room for error. A neat, narrow bead in a colour to match keeps the clean look.
uPVC windows
We clean the frame edge carefully so the plastic is not marked, then the sealant goes in between frame and wall.
FAQs for Radwell
Will you come out to Radwell?
Yes, Radwell is covered. We work across London and the South East, and smaller places are part of that. The journey is planned ahead, so it helps to know about access.
Do you cover Radwell for window mastic?
Yes. We work across London and the South East, and Radwell is part of that. Just phone 0345 464 0079 or send us an email with a few details of the job, and we will give you a clear price.
Can new sealant go over the old?
No. New silicone won’t bond to old silicone, and it traps any mould or water underneath. We remove it all first.
Where do you work from?
Our base is in Crawley, and we work across South East England, London and Scotland.
I rent my home. Can I book you?
We’re happy to deal with the tenant, landlord or agent. Get your landlord’s agreement first.
How long does it take to reseal the windows on a house?
It depends on access, the old mastic and the size of the frames. You will know the timing when we quote.
Do you remove the old sealant?
Yes, every time. New silicone doesn’t stick to old silicone, so any old material comes out before anything new goes in.
Can resealing stop a draught around my window?
In many cases. Air often gets in between the frame and the wall, and sealing the inside and outside joints closes that path.
Landlord and commercial work in Radwell
From a single let to a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a 12-month guarantee.
Landlords and letting agents in Radwell can book us as well as homeowners. Resealing between tenancies keeps a property looking cared for.