Oxfordshire · England
Window Mastic in St Clement's
Window mastic for St Clement's, by sealant specialists with 20+ years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Mastic that’s falling out in pieces
- Rain getting in at the frame or under the sill
- Sealant in the wrong colour for the frame
DIY versus a professional finish
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it fails, we can still redo it.
Sealing over old silicone is the commonest DIY error. New silicone won’t bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
Window mastic in St Clement's, done properly
Some gaps around frames are far deeper than they look. Filling it with sealant alone leaves a joint that can’t move properly, so deep gaps get backing rod first. That way the new bead bonds to the frame and the wall only. If you have sealant in the wrong colour for the frame and water coming in at the bottom corners of a door, we can put it right.
In smaller places like St Clement's, 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.
Each job carries a 12-month guarantee, whatever its size.
- Location
- St Clement's (OX4, OX1, OX3)
- Wider area
- Oxfordshire
- Cover
- A year, on every job
- Price
- A clear quote up front
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Quotes for window mastic in St Clement's
We quote each job individually. These are the things that affect it:
- Whether there’s mould to deal with
- Any working-time requirements on site
- The old material and how stubborn it is
- The number of rooms or windows
Commercial jobs are quoted on the same basis as homes: the amount of work, how we reach it and what it needs. Call for a quick quote and we’ll explain what it covers.
Asking for a quote
When you contact us, these details help:
- Where the job is, and your postcode
- Any previous sealing or DIY work
- How many joints, rooms or windows are involved
- What’s wrong with the joints now
Call for a quick quote, or email us if that is easier. Tell us about the joints that need doing and we will talk you through the work before giving you a price.
What we’re called out for in St Clement's
Sills take more water than any other part of a window, so the sill ends and the joint below the frame are common leak points. Failed sealant there lets rain into the wall or behind the frame.
If you can see any of these, it’s time to have the joints looked at:
- Cracked internal joints between frame and plaster
- Gaps where the sill meets the wall
- Hard, cracked sealant around windows
- Mastic that’s falling out in pieces
Managing a site like East Oxford Primary School? Then its window and door frames need their mastic kept sound, just like a home’s.
What to look for in a quote
- Whether they seal over old material or remove it
- What happens if they find a problem under the old sealant
- How the colour is chosen
- Whether VAT is included
Nearby places to St Clement's
Other services in St Clement's
St Clement's questions
Do you work for landlords with property near Oxford station?
Yes, rental work is part of what we do. You can ring 0345 464 0079 or drop us an email with the address and a few details, and we will give you a fixed price before we start.
Do you cover smaller places like St Clement's?
Yes, we do. 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.
Will new mastic stop draughts?
Often, yes. The gap between frame and wall is a common source of draughts, and resealing inside and out closes it.
Do I have to be there?
That depends on where the joints are. Inside work needs someone to give us access, while outside work can sometimes be arranged differently.
Can new window sealant be painted?
Not generally, if it’s silicone. Tell us your decorating plans and we’ll pick a sealant to suit.
Is it worth trying it myself?
That depends on the joint. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional.
How long does it take to reseal the windows on a house?
A handful of frames is a short visit. We confirm the timing with your quote.
Can you match the sealant to my frames?
Yes, in most cases. Tell us the frame colour when you get in touch and we’ll match it as closely as we can.
Looking after it afterwards
A little care helps the new joints last. We recommend:
- Check the mastic once a year
- Make sure the drainage slots aren’t blocked
- Do not use solvent cleaners on the joint
- Air rooms to keep condensation down around windows
Clean the frames with mild soapy water, and keep solvents and harsh chemicals off the joint.
A small gap around a frame only grows. As the old mastic shrinks further, more air gets through, and heat escapes around the frame. Resealing closes it.
What window mastic looks like in St Clement's
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. Historic houses like Holywell Manor (about 0.5 miles north-west) are a reminder that the area around St Clement's has older buildings as well as new. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
Letting a property close to Oxford station? Then sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. For an older house near a landmark such as St Clement's Church, the joint between an old wall and a newer frame is normally the first place rain gets in.
St Clement's is about 1 mile west of Oxford, in Oxfordshire. If you need window mastic in St Clement's, it’s easy to get a quote: please ring 0345 464 0079 or email us. We are based in Crawley and cover Oxfordshire. Our Oxfordshire coverage runs to 443 places, and St Clement's is one of them.
Jobs for window mastic in OX4, OX1 and OX3 is quoted and booked the same way as anywhere else. We cover properties on Rose Lane, Alma Lane and Avenue Lane and the roads around them. If you’re just outside St Clement's, we cover Oxford (1 mile east), Headington Hill (1 mile north-east), St. Ebbes (1 mile west), New Marston (1 mile north) and Donnington (1 mile south). Further out, we also cover Didcot (10 miles south), Bicester (11 miles north), Abingdon-on-Thames (5 miles south), Witney (11 miles west), Carterton (15 miles west) and Thame (12 miles east).
What’s near St Clement's
We work in homes and buildings around Cheney School, Alexander Library of Ornithology and Oxford Media & Business School and the streets around them. Also close by are Headington Hill Park (less than half a mile north-east) and Oxford Coach & Horses pub (under half a mile east). The closest station to St Clement's is Oxford station, about 1.3 miles west. Nearby you will also find Oxford Castle (0.9 miles west) and Frank Cooper Marmalade Museum (within half a mile west). Green spaces nearby include CS Lewis Nature Reserve and Headington Hill.
How it works
Once we are on site, we check the joints match what you told us. If anything is different, we explain it before carrying on. After that, the work takes anything from an hour or two to a full day, depending on how many frames there are. In a smaller place like St Clement'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.
- First, we confirm safe access to each frame.
- Old, cracked mastic is removed completely, 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.
- We tool the joint so water runs off, then clear up.
Getting ready for the visit
- Let us know about stairs, lifts or work at height
- Tell us about any water getting in
- Plan for the work area to be out of bounds to pets and children
How to get a quote
Asking for a quote is easy: let us know what needs doing and where. Photos by email help us understand the job, and we’ll take it from there.
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What the job involves on each surface
Composite doors
A composite door usually sits in a plastic outer frame, and the joint around it is sealed like a window. The bead is colour-matched to the frame.
Window sills
Sills catch the water running down the glass, so the sill ends and the joint under the frame are vital. They’re cut out and resealed with exterior sealant.
Why act early in St Clement's
Running fresh sealant over the old joint is tempting, but it will not grip old, dirty sealant. It peels before long, and water still gets in behind. The old mastic has to come out. In a smaller place like St Clement's, wherever a wall is exposed, a failed outside joint is a real source of damp. Indoors, a failed seal lets water into floors and panels as it would anywhere.
A failed joint rarely gets cheaper to fix by waiting, because water and mould keep working on it. If you’re not sure whether it needs doing, call 0345 464 0079 or drop us an email and we’ll give you an honest view and a quote.
What you get with us
- You choose the colour before work begins
- Trusted Arbo and Everbuild sealants
- ARBOMaster approved applicator
- Sealant colour chosen to suit
Take a look at how sealant jobs are priced or our reviews.