Oxfordshire · England
Dorchester Window Mastic
Window and door frames in Dorchester need attention? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Cracked or shrunken mastic around the frame
- A bead that doesn’t match the frame
- Draughty joints inside around the window
What window mastic looks like in Dorchester
With historic houses such as Clifton Hampden Manor (about 2 miles west) nearby, there’s older building stock in the area around Dorchester as well as newer homes. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window. London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Rented homes near Culham station change hands often, and sound mastic around windows and doors keeps out the draughts and damp that tenants notice first. Managing a site like Dorchester St Birinus Church of England School? Then its window and door frames need their mastic kept sound, just like a home’s.
Dorchester is about 4 miles north-east of Didcot, in Oxfordshire. We provide window mastic to homes and businesses in Dorchester and the surrounding area. Our Oxfordshire coverage runs to 443 places, and Dorchester is one of them. You can also see our page for Oxford, about 8 miles away.
Every address in OX10 is covered for window mastic. We cover properties on High Street, Queen Street and Queens Close and the roads around them. We also cover the places around Dorchester: Burcot (1 mile north-west), Little Wittenham (1 mile south-west), Berinsfield (1 mile north), Warborough (1 mile east) and Shillingford (1 mile south-east). Within a short drive, we also cover Oxford (8 miles north), Didcot (4 miles south-west), Abingdon-on-Thames (5 miles north-west), Thame (11 miles north-east), Wantage (12 miles west) and Henley-on-Thames (14 miles south-east).
Local landmarks in Dorchester
Typical jobs here are in homes near The White Hart Hotel Bar and the streets around them. For rail, the closest station is Culham station, about 3.1 miles west of the centre. Other landmarks nearby include Brightwell Castle (2.3 miles south) and Littlemore Hospital (5.6 miles north-west). Green spaces nearby include Ewelme Watercress Beds and Wittenham Clumps.
About our window mastic in Dorchester
There are two joints on most windows. Outside, the mastic keeps rain out; inside, the joint between frame and plaster stops draughts and tidies the reveal. We seal one or both, depending on what’s needed. We work on uPVC windows, aluminium frames and window sills, and the jobs we see most are draughty joints inside around the window and gaps left after new windows were fitted.
Homes in small places like Dorchester often stand in the open, with little to shelter their windows from wind and rain. Exposed frames and sills lose their mastic sooner than sheltered ones.
Big or small, you get the same 12-month guarantee.
- Location
- Dorchester (OX10)
- Wider area
- Oxfordshire
- Cover
- 12 months on all our work
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Quotes for window mastic in Dorchester
The quote reflects the job in front of us. We take into account:
- How many rooms, windows or areas are involved
- When we can work, for business premises
- The type of sealant required
- Mould in or behind the old joints
Homes and businesses are quoted the same way: the amount of work, the access and the products needed. Call for a quick quote and we’ll explain what it covers.
Asking for a quote
A few details help us give you an accurate quote. When you get in contact, it helps to mention:
- Any previous sealing or DIY work
- How we’d reach the joints
- Where the property is
- The rough size of the job
To get a quote, ring 0345 464 0079 or email us and tell us where the job is and what the problem looks like. We’ll send you a clear quote before any work starts.
Common problems we fix in Dorchester
Frames are never completely still. A plastic or aluminium frame lengthens in sunshine and shortens as it cools, while the brick or render around it hardly moves. If the sealant can’t stretch, it splits.
Any of these means the joints need attention:
- Cold air getting in at the frame edge
- Mastic that has split away from the wall
- Old mastic that has gone black or come away
- Damp patches on the reveal after heavy rain
In the older streets around Dorchester Abbey, the joint between an old wall and a newer frame is usually the first place rain gets in.
Before booking anyone
- Whether the sealant suits the joint
- What insurance they hold
- What happens if the job turns out different
- Whether VAT is included
What sealant work can’t fix
It helps to know what we cannot do too:
- A sash or casement that will not close properly
- Penetrating damp from a failed cavity tray or render
- Misting between the panes of a double-glazed unit (that needs a new unit)
If in doubt, ring 0345 464 0079 or drop us an email and we’ll say what we think before you book.
Joints and surfaces we work on
- Patio & French doors
- Window sills
- Composite doors
- Aluminium frames
- Timber windows & doors
- uPVC windows
Can I do it myself?
Sealing over old silicone is the commonest DIY error. New silicone won’t bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
What happens on the day
Most of a good job is in the preparation, so that is where we spend the time. Every joint is cleaned and dried before new material goes in. In total, it normally takes most of a day for a typical house, less for a few frames. In a small place like Dorchester, access is normally the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- First we look at every frame and agree the list.
- The old mastic is cut out and the surfaces cleaned back.
- We fit backing rod in deep gaps so the sealant is the right depth.
- New exterior sealant goes on in a matching colour and is tooled smooth.
- We clear up and check every joint is fully closed.
Preparing for the visit
- Move anything stored near the joints
- Where the joints are inside, avoid wetting them before we arrive
- Tell us about any water getting in
Ask for a quote
Every job is quoted individually, so the first step is telling us about yours. Just phone 0345 464 0079 or drop us an email with the details and send pictures if you have them.
Read more
Also near Dorchester
What else we do in Dorchester
Work for landlords, hotels and businesses
We also work for property managers and facilities teams in Dorchester and across Oxfordshire. Several sites can go on one quote.
For anyone letting property in or around Dorchester, several properties can go on one quote. Just tell us the addresses and what each one needs, and photos by email help.
How to look after the new joints
Simple care keeps the joints in good condition. Our advice:
- Keep jet washers away from the mastic
- Keep paint and stain on wooden frames in good order
- Walk round the house once a year and look at the joints
- Do not use solvent cleaners on the joint
A yearly look round the frames is enough. Small splits are simple to catch before they leak.
A failed joint lets water into the wall a little at a time. You might not see it until plaster blows or a damp patch appears inside. Catching it early keeps the fix to a reseal.
Common questions in Dorchester
Do you cover Dorchester for window mastic?
Yes, Dorchester is within the area we cover. We work across London and the South East. You can call 0345 464 0079 or send us an email and tell us what needs doing, and we’ll give you a clear price.
Will you come out to Dorchester?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Will you leave a mess?
Tidy work is part of the job. Nearby surfaces are protected, and we clear up when we’re done.
I’m a tenant. Can you help?
We can work for tenants, landlords or agents. Just make sure your landlord agrees.
How long before the joint can be used?
That depends on the sealant used, so follow the cure time we give you.
Will the old sealant be removed?
Always. Sealing over old sealant is the main reason resealing fails early, and it’s something we never do.
Is there any odour?
Some sealants have a smell while they cure, which fades as it sets. Ventilation helps.
Can you seal over the old sealant?
No, it will not last. It may look fine at first, but the new layer lifts away from the old one. The old sealant has to come out completely.