Oxfordshire · England
Crowell Sand Mastic
Problem with your window and door surrounds in Crowell? We cut out the old, prepare the joints and apply the right sealant.
- Cement or filler used on old window joints that has cracked
- Silicone on a period window that looks wrong
- Mastic round period door frames that has failed
How we handle sand mastic in Crowell
For a listed home or one in a conservation area, ask your local planning authority whether consent is needed for work to windows. Sand mastic is often favoured as a like-for-like material. If you have wind and rain getting in round a sash window and old sand mastic that has cracked, crumbled or fallen out, we can put it right, whatever the surface.
Outdoor sealant needs dry, clean surfaces, so work on frames around Crowell is planned for dry weather. Tell us about access to every side of the house, including upper-floor windows.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we will put it right.
- Location
- Crowell (OX39)
- Region
- Oxfordshire
- Guarantee
- A year, on every job
- Quotes
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Crowell homes and the weather
With historic houses such as Adwell House (about 2.9 miles west) nearby, there’s older building stock in the area around Crowell 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. Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Managing a site like Mill Lane Community Primary School? Then its window and door frames need their mastic kept sound, just like a home’s. If you let a flat or house near Princes Risborough station, older sash windows in a rental need their mastic kept sound to keep the weather out.
Crowell is about 4 miles south-east of Thame, in Oxfordshire. We provide sand mastic to homes and businesses in Crowell, as part of our work across Oxfordshire. Our Oxfordshire coverage runs to 443 places, and Crowell is one of them. We also work in Oxford, about 14 miles from Crowell.
Jobs for sand mastic in OX39 is quoted and booked the same way as anywhere else. Other places close to Crowell include Kingston Blount (1 mile west), Oakley (1 mile north-east), Crowell Hill (1 mile south-east), Aston Rowant (1 mile south-west) and Postcombe (2 miles west). Larger places within reach include Oxford (14 miles west), Didcot (15 miles west), Abingdon-on-Thames (15 miles west), Thame (4 miles north-west), Henley-on-Thames (11 miles south) and Benson (9 miles south-west).
Landmarks near Crowell
Around Crowell, our work takes us to homes and buildings near The Shepherd's Crook pub and the streets around them. The nearest railway station is Princes Risborough station, roughly 3.9 miles north-east. Well-known places in the area include Thame Community Hospital (4.2 miles north-west). Green spaces nearby include Oakley Hill nature reserve and Bald Hill.
Surface by surface
Brick reveals
Loose mastic comes out and deep gaps are packed before pointing.
Sash and case windows
Sash windows are where we do most sand mastic work. We renew the mastic round each box.
When something else is needed
To be straight with you, there are a few things sealant won’t fix:
- Decayed frames that need repair
- Cracked or broken glass
- Sashes that rattle, stick or will not open
Not sure which it is? You can call 0345 464 0079 or send us an email and we will tell you honestly before booking.
Surfaces we seal
- Stone surrounds
- Period & listed homes
- Sash and case windows
- Tenement windows
- Timber door frames
- Brick reveals
Can I do it myself?
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it peels away and traps moisture behind it. Everything old must be removed first.
If you are set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
What affects the quote in Crowell
We do not publish a price list, because no two jobs are the same. What we look at:
- The number of rooms or windows
- The product the joint needs
- When we can work, for business premises
- The old material and how stubborn it is
We do not show prices on the website, because each job is priced on what it involves. Call for a quick quote.
What to tell us for a quote
To make quoting easier, let us know:
- The address or postcode of the job
- Photos by email, if that is easy
- How we’d reach the joints
- Any previous sealing or DIY work
Want a quote for sand mastic? Please phone 0345 464 0079 or send us an email with a few details. You will know what we plan to do, and what it will cost, before any work begins.
Crowell questions
Will you come out to Crowell?
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.
Do you cover Crowell for sand mastic?
Yes. We work across London and the South East, and Crowell is part of that. You can phone 0345 464 0079 or email us and let us know what needs doing.
Do I have to be there?
Access is agreed with you when the job is booked. Indoors, that generally means someone at home.
What do you need from me for a quote?
Just the basics: the address or postcode, what’s wrong and any access issues. Then ring 0345 464 0079 or send us an email.
Do you offer different sealant colours?
Most of the time, yes. We will tell you which colours the right product comes in.
Can I do it myself?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Where is Mr Mastic based?
Our base is Crawley. Our area covers South East England, London and Scotland.
I’m a tenant. Can you help?
Of course. Check with your landlord; we can send the quote to them too.
What happens on the day
Once we are on site, we compare the joints with what we discussed. If anything is different, we explain it before carrying on. After that, the work takes anything from a few hours to a full day, depending on how many windows. In a small place like Crowell, access is usually the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- We check each window surround and the condition of the joint.
- The joint is raked out and cleaned.
- We fill deep gaps so the new mastic isn’t too thick.
- We point the joint with sand mastic by hand.
- We finish the mastic to a tidy line.
Before we arrive
- Let us know if you’ve seen damp or leaks
- Plan for the work area to be out of bounds to pets and children
- Move anything stored near the joints
Ask for a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints.
Advice
What we are called out for in Crowell
Scraping and sanding before painting can loosen old mastic. It’s often found when windows are being prepared for paint.
It’s worth asking for a quote if you see:
- Draughts and rain around sash boxes
- A silicone bead on a sash window that spoils the look
- Mastic dropping out of the joint
- Mastic round period door frames that has failed
For an older house near a landmark such as Church of the Nativity of the Blessed Virgin Mary, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Questions to ask before you book
- What preparation is included
- What the cure time is
- Is the old sealant removed completely?
- What happens if they find a problem under the old sealant
Also near Crowell
What else we do in Crowell
Landlord and commercial work in Crowell
We also work for businesses, from offices to washrooms and kitchens. On commercial sites, working times can be discussed when we quote.
For anyone letting property in or around Crowell, several properties can go on one quote. Send us the addresses and the work at each.