Southampton · England
Window & door mastic in St Mary's, Southampton
Window mastic across St Mary's and nearby, with old sealant always removed completely and a 12-month guarantee.
- Cracked sealant at the sill ends
- Rain getting in at the frame or under the sill
- Old mastic that has gone black or come away
Window mastic in St Mary's, done properly
Over two decades of sealing frames has taught us which products suit which walls. We’re fully insured ARBOMaster approved applicators, and we give a 12-month guarantee on the work. If you have gaps where the sill meets the wall and sealant in the wrong colour for the frame, we can put it right, on patio & French doors, uPVC windows and timber windows & doors alike.
Homes around St Mary's range from older properties to newer houses, and their windows range just as widely. Each frame material needs the right sealant against the right wall.
Every job is covered by a one-year guarantee.
- Place
- St Mary's (SO14, SO15, SO18)
- Region
- Southampton
- Guarantee
- 12 months on all our work
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Keeping the joints in good condition
So the new joints stay in good condition:
- Don’t use solvent cleaners on the joint
- Keep paint off silicone joints
- Keep paint and stain on wooden frames in good order
- Wipe condensation off the frames
Check the drainage slots in the frames aren’t blocked, so water can run away instead of sitting against the joint.
On timber windows, water behind the joint can lead to rot. Once wood has rotted, it needs repair before it can be sealed, so it pays to reseal before that happens.
Places near St Mary's
Also in St Mary's
Do you need window mastic in St Mary's?
Frames are never completely still. A plastic or aluminium frame lengthens in sunshine and shortens as it cools, while the masonry beside it stays put. If the sealant can’t stretch, it splits.
Most people get in touch when they notice something like this:
- Rain getting in at the frame or under the sill
- Cracked internal joints between frame and plaster
- Rushed sealant from a window installation
- Sealant in the wrong colour for the frame
If you look after a building such as Hope Community School Southampton, the mastic around its windows and doors needs looking after like any other building’s.
Questions to ask before you book
- Who turns up on the day
- How long to leave it before use
- Whether VAT is included
- Which sealant they’ll use, and why
Quotes for window mastic in St Mary's
There’s no set price list. What we look at:
- When we can work, for business premises
- Whether there’s mould to deal with
- How much old sealant there is and how hard it is to remove
- Whether the work is at height
No two jobs are quite the same, so each one gets its own quote. Size, access and the product the joint needs all make a difference, and we will explain the quote if you ask.
What we need to know
You do not need to know the technical terms. Just tell us:
- Any previous sealing or DIY work
- What’s wrong with the joints now
- Pictures of the joints, sent by email
- The address or postcode of the job
For a quote, phone 0345 464 0079 or email us with the location and a short description of the problem. We will give you a clear quote before any work starts.
Common questions in St Mary's
Does living near the coast affect window mastic in St Mary's?
Near the sea, outside joints face more wind, rain and salt than they would inland, so preparation and the right sealant matter all the more. Walls facing the sea are generally the first to need attention.
Do you cover smaller places like St Mary's?
Yes. St Mary's is within the area we cover, which takes in towns, villages and rural addresses. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
What do you put in the joint?
The product depends on the job: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. We use products from Arbo and Everbuild.
Can new sealant go over the old?
No, because it fails. We remove every bit of old sealant first, so the new joint bonds to clean surfaces.
Are you insured?
Yes. We’re fully insured.
Can you reach windows above the ground floor?
Yes, as long as they can be reached safely. Tell us about access when you get in touch so we can plan the job.
What should I tell you?
Only a few details: where it is, what you’ve noticed and how we reach it. Then ring 0345 464 0079 or email us.
Do the sealants smell?
It depends on the product. Some smell for a while, some hardly at all.
Honest limits
Before booking, it’s worth knowing the limits too:
- Draughts through the window seals rather than the frame
- A sash or casement that won’t close properly
- Misting between the panes of a double-glazed unit (that needs a new unit)
If in doubt, phone 0345 464 0079 or send us an email and we’ll say what we think.
What we seal
- Composite doors
- Timber windows & doors
- Aluminium frames
- Patio & French doors
- Window sills
- uPVC windows
What the job involves on each surface
Window sills
Stone and concrete sills have their own joints, and the joint under the frame can let rain run behind. Those are sealed with a product suited to stone or concrete.
Composite doors
Composite doors are normally hung in an uPVC-type frame, so its perimeter joint is sealed much like a window. The bead is colour-matched to the frame.
Should I try it myself first?
Sealing over old silicone is the commonest DIY error. Silicone doesn’t stick to old silicone, so it peels away and traps moisture behind it. All the old material has to come out first.
A careful DIYer can reseal a simple joint, 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.
Windows and doors in St Mary's
St Mary's is close to the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. That’s hard on the mastic around window and door frames, especially on the side facing the sea. 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 St Mary's Church include some older properties, and the joint between an old wall and a newer frame is normally the first place rain gets in. For landlords with property near Southampton Central station, sound mastic around windows and doors keeps out the draughts and damp that tenants notice first.
St Mary's is about 1 mile south of Southampton, in Southampton. Homes, rented property, offices and hotels in St Mary's is covered for window mastic, old or new, large or small. The work is guaranteed for a year. We cover 40 towns and villages across Southampton, large and small.
Jobs for window mastic in SO14, SO15 and SO18 is quoted and booked the same way as anywhere else. Whether your property is on New Road, Ogle Road and Marsh Lane or a nearby road, we can help. Neighbouring places we cover for window mastic include Northam (1 mile north-east), Inner Avenue (1 mile north), Peartree Green (1 mile east), Southampton (1 mile north) and Bitterne Manor (1 mile north-east). Larger places within reach include Chartwell Green (3 miles north-east), Harefield (3 miles east), Maybush (3 miles north-west), Coxford (3 miles north-west), Lordswood (3 miles north-west) and Eling (4 miles west).
Local landmarks in St Mary's
Typical jobs here are in homes near The Joiners pub, Woolston School and Houndwell Park, among other places. St Mary's’s nearest station is Southampton Central station, roughly 0.8 miles west of the centre. Well-known places in the area include Netley Castle (2.5 miles south-east) and Bargate Guildhall Museum (less than half a mile south-west). Green spaces nearby include Netley Common.
What we do, step by step
We bring everything the job needs with us, so there’s nothing for you to buy. After a quick look at the joints together, the area is protected and the work begins. Most jobs take most of a day for a typical house, less for a few frames. In a smaller place like St Mary's, parking is seldom the issue; lanes, gates and long drives are worth mentioning. For outside work, side access and the height of the joints help us plan.
- Each frame is looked over and we agree which ones need resealing.
- We remove the old mastic and clean the frame edge and wall.
- Deep gaps get closed-cell backing rod to set the depth.
- A flexible exterior sealant is applied in a colour to suit the frame.
- We tool each bead neatly and check every joint is closed.
Getting ready for the visit
- On commercial sites, let us know about site rules
- Let us know if you’ve seen damp or leaks
- Move anything stored near the joints
Getting a quote
Asking for a quote is easy: let us know what needs doing and where and its rough size. A few pictures by email make the job easier to understand, and we will take it from there.