Oxfordshire · England
Window & door mastic in Northend, Oxfordshire
Our applicators work in Northend on mastic around window and door frames, sills and patio doors. Old material cut out, joints cleaned and sealed neatly and a 12-month guarantee.
- A bead that does not match the frame
- Rain getting in at the frame or under the sill
- Mastic that has split away from the wall
How it works
All our tools and materials come with us in the van, so you do not need to buy or prepare anything. After a quick look at the joints together, the area is protected and the work begins. It normally takes a few hours for a few frames, or a day or more for a whole house. Somewhere as small as Northend, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- 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
- Clear the area around the work
- For business premises, tell us about site rules or sign-in
- Mention any tricky access
Getting a quote
For a quick quote, get us on the phone, or send an email if you’d rather. Describe what needs sealing and we will talk you through the work and give you a clear quote.
Related advice
Window mastic in Northend, done properly
Mr Mastic’s applicators have more than 20 years’ experience with window and door sealants. We’re fully insured ARBOMaster approved applicators, and every job is covered by a 12-month guarantee. If you have mastic that’s falling out in pieces and gaps left after new windows were fitted, we can help, on patio & French doors, timber windows & doors and uPVC windows alike.
In a village or hamlet like Northend, older cottages and farmhouses often have timber windows set in stone or brick. Not every older frame suits a modern silicone bead, and sometimes a traditional sand mastic is the better choice.
You’re covered for a year from the day we finish. If there’s a problem with it, please call 0345 464 0079 or email us.
- Where
- Northend (RG9)
- Region
- Oxfordshire
- Guarantee
- A year, on every job
- Quotes
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Do you need window mastic in Northend?
Timber windows bring their own problems. Mastic painted over many times cracks with the paint, and the wood moves with damp as well as heat.
People usually contact us when they notice one of these:
- Old mastic that has gone black or come away
- Cold air getting in at the frame edge
- Gaps left after new windows were fitted
- Water coming in at the bottom corners of a door
Around Northend, as everywhere, window mastic is only as good as the preparation behind it.
Before booking anyone
- The length of the guarantee
- How the joint is cleaned and prepared
- Whether all the old sealant comes out first
- How much experience the applicator has
What affects the cost of window mastic
For a quick quote, just ask. The main things that affect it are:
- Whether the work is at height
- Whether there’s mould to deal with
- The old material and how stubborn it is
- Any working-time requirements on site
Combining jobs into one visit is normally more efficient than separate visits. You will get one clear quote for the whole job.
Helping us quote
What to tell us when you ask for a quote:
- Whether it has been sealed before
- Access, such as stairs, a lift or height
- Where the property is
- Whether it’s a home or a business
We quote each job on its own. Simply call 0345 464 0079 or send us an email and describe the job, and pictures are welcome.
Your questions about window mastic in Northend
Do you cover smaller places like Northend?
Yes. Northend 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.
Is window mastic in Northend guaranteed?
All our work, in Northend and everywhere else, comes with a 12-month guarantee. We’re also fully insured and ARBOMaster approved.
Are you insured?
Yes, we’re fully insured for domestic and commercial work.
Can you quote for more than one area?
Yes. Tell us about everything you’d like done and we’ll quote it together.
Where is Mr Mastic based?
We’re a Crawley-based firm. Our area covers South East England, London and Scotland.
How long will my window job take?
It depends on access, the old mastic and the size of the frames. We will tell you how long your job needs when we quote.
Can you seal over the old sealant?
No, because it fails. We remove every bit of old sealant first, so the new sealant bonds properly.
Will new mastic stop draughts?
Yes, if the air is getting in around the frame. If it’s coming through the window seals, we’ll tell you.
Looking after it afterwards
After the cure time, these simple habits help:
- Don’t paint over the silicone
- Keep solvents and bleach off the sealant
- Check the mastic once a year
- Clean frames with a soft cloth and soapy water
Keep the new mastic undisturbed while it cures, for as long as we advise. Don’t point a pressure washer at the joints.
Wet, windy weather is when failed mastic shows itself, but sealant goes on best when frames and walls are dry. Dealing with it when you first notice a crack avoids chasing leaks through the wet months.
Northend homes and the weather
Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. With historic houses such as Stonor Park (about 2.1 miles south) nearby, there’s older building stock in the area around Northend as well as newer homes. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic.
Historic houses such as Stonor Park, about 2.1 miles south, show how far back building around Northend goes, and older homes nearby need a sealant that suits their walls.
Northend is about 8 miles north-west of Marlow, in Oxfordshire. Northend gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a 12-month guarantee. We cover 443 towns and villages across Oxfordshire. Reading is on our list too, about 12 miles from Northend.
Here we cover the RG9 postcode area for window mastic. Close by, we work in Christmas Common (1 mile west), Turville Heath (1 mile south-east), Ibstone (1 mile north-east), Stonor (2 miles south) and Howe Hill (2 miles west). Further out, we also cover Oxford (15 miles north-west), Didcot (13 miles west), Abingdon-on-Thames (15 miles west), Thame (8 miles north), Henley-on-Thames (7 miles south) and Benson (7 miles west).
Near you in Northend
For a walk, there’s Bald Hill and Aston Rowant NNR.
Towns and villages near Northend
Other services in Northend
Why it’s worth doing now in Northend
Choosing the product is half the job. Interior caulk and bathroom silicone aren’t made for exterior frame joints. An exterior, low-modulus sealant stays flexible in sun and frost. In a small place like Northend, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
Commercial jobs are quoted on the same basis as homes: how much there is to do, how we reach it and what it needs, plus any working-time requirements on site. Ask us for a quote and we will go through it with you.
Why us?
- Anti-fungal silicone where joints get wet
- 180+ five-star Google reviews
- Neat joints and a tidy finish
- An ARBOMaster approved applicator
Should I try it myself first?
Some sealant jobs are within reach of a careful DIYer, 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.
The biggest DIY mistake is sealing over old sealant. Silicone doesn’t stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
Different surfaces, different methods
Patio & French doors
Patio and French doors have the longest joints on most houses. Most leaks start at the bottom corners, so they get particular care.
uPVC windows
We clean the frame edge carefully so the plastic isn’t marked, then the new bead is laid against the frame and the wall.