Hampshire · England
Sand mastic for sash & case windows in Thedden, Hampshire
We cover Thedden for traditional burnt sand mastic around sash and case windows and doors in stone and brick. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Tired mastic found when preparing windows for paint
- Wind and rain getting in round a sash window
- Patchy fillers round a sash window
How we handle sand mastic in Thedden
On many period windows, sand mastic looks right and suits the building. On modern frames we’d normally use a flexible sealant, and we’ll talk through which suits your home. If you’re dealing with cracked mastic round a front door frame and open joints round the window box, we can help, whatever the surface.
Around Thedden, many homes face open ground, so their windows and doors take the full weather. Exposed frames and sills lose their mastic sooner than sheltered ones.
We stand behind the work with a one-year guarantee, so you’re covered after we’ve gone.
- Place
- Thedden (GU34)
- Wider area
- Hampshire
- Guarantee
- 12 months on all our work
- Quote
- A clear price before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Honest limits
New sealant can’t fix everything, and we will tell you before work begins. Sealant won’t put right:
- Planning or listed building consent (your local planning authority decides)
- Cracked or broken glass
- Sash cords, weights and draught-proofing of the sashes
Not sure which it is? You can phone 0345 464 0079 or email us and we will tell you honestly.
Joints and surfaces we work on
- Period & listed homes
- Tenement windows
- Sash and case windows
- Brick reveals
- Stone surrounds
- Timber door frames
Thedden questions
Do you cover smaller places like Thedden?
Yes, Thedden 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.
I let a flat near Alton station. Can you help?
Yes, rental work is part of what we do. You can ring 0345 464 0079 or send us an email with the address and a few details, and we will give you a fixed price before work begins.
Are you fully insured?
Yes. We are fully insured.
Do you remove the old sealant?
Yes, always, and completely. New sealant will not bond properly to old, so any old material comes out before anything new goes in.
How much does sand mastic cost in Thedden?
There’s no set price, as it depends on the job: its size, the old material, access and the product needed. We agree the price before any work begins.
Should I use sand mastic or silicone?
For period timber windows in stone or brick, sand mastic is often the better fit. On modern frames, we’d normally use a flexible sealant, and we’ll explain why.
Do you guarantee sand mastic work?
All our work has a 12-month guarantee, and we’re fully insured.
Can sand mastic be painted?
Traditional guidance is not to paint over sand mastic. If you are redecorating the window, ask us first and we’ll advise.
DIY sealant or a professional job?
The difference is mostly in the preparation and the product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions, and the work is guaranteed for a year.
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Also in Thedden
Aftercare tips
To keep the joints looking good and working properly:
- Get any rot dealt with first
- Ask us before painting near the mastic
- Avoid patching sand mastic with silicone
- Inspect the joints round the windows every year or so
Avoid painting over the new mastic, as traditional guidance advises. Ask us before any decorating around it.
Sound mastic protects the frame. Once it fails, water can sit against the timber, which can lead to rot.
Signs you need sand mastic in Thedden
Decorating can disturb tired mastic. Many people find it crumbling when they prepare the windows.
Most people get in touch after spotting one of these:
- Mastic dropping out of the joint
- Cracked mastic round a front door frame
- Gaps between timber frames and stone or brick
- Modern sealant on a period surround
If you look after a building such as Amery Hill School, its window and door frames need their mastic kept sound, just like a home’s.
What to look for in a quote
- Which sealant they’ll use, and why
- Which colour the sealant will be
- How hidden problems are handled
- Who turns up on the day
Windows and doors in Thedden
With historic houses such as Bentworth Hall (about 1 mile west) nearby, there’s older building stock in the area around Thedden as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window. The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
If you live in an older home near St Peter's, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. Rented homes near Alton station change hands often, and older sash windows in a rental need their mastic kept sound to keep the weather out.
Thedden is about 2 miles west of Alton, in Hampshire. Whether you’re in the middle of Thedden or further out, we cover sand mastic for every kind of property. Thedden is one of 683 towns and villages in Hampshire we cover for sand mastic. We also work in Reading, about 21 miles from Thedden.
Our applicators cover all of GU34 for sand mastic. Neighbouring places we cover for sand mastic include Beech (1 mile south-east), Wivelrod (1 mile south-west), Bentworth (1 mile north-west), Holt End (1 mile west) and New Copse (2 miles west). We also work in nearby towns such as Basingstoke (9 miles north), Winchester (14 miles south-west), Farnborough (15 miles north-east), Fleet (12 miles north-east), Aldershot (13 miles north-east) and Petersfield (10 miles south).
Near you in Thedden
For rail, the closest station is Alton station, roughly 2.6 miles east of the centre. Other landmarks nearby include Alton Community Hospital (1.6 miles east) and Barton Castle (3.9 miles west). Not far away are King's Hill.
Work for landlords, hotels and businesses
Housing providers, facilities teams and property managers book us too. We can quote a run of properties together.
Businesses can book us for washrooms, kitchens, offices and more. For commercial premises, we can talk through working times when we quote.
The process
At the end, we look at the finished work together and tell you how long to leave it. The visit itself usually takes anything from a few hours to a full day, depending on how many windows, depending on the size of the job. Somewhere as small as Thedden, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- We check the window surrounds and agree which joints need renewing.
- We rake out the old mastic and clean the joint.
- We pack any deep gaps so the mastic sits at the right depth.
- We mix the sand mastic and apply it by hand, shaping it to the joint.
- We dress the surface so it sits neatly against the masonry.
Getting ready for the visit
- Where the joints are inside, avoid wetting them before we arrive
- Mention any parking rules near the property
- Mention any tricky access
Getting a quote
For a quote, call 0345 464 0079 or drop us an email with the location and a short description of the problem. We will give you a clear quote before any work starts.
Read more
What the job involves on each surface
Timber door frames
A neat sand mastic joint round a front door suits a period home.
Period and listed homes
Sand mastic is the like-for-like choice for many period homes. If your home is listed, ask your local planning authority about consent.