Hampshire · England
Sand Mastic in Northbrook
Professional sand mastic in and around Northbrook, with old sealant always removed completely and a 12-month guarantee.
- Wind and rain getting in round a sash window
- Old sand mastic that has cracked, crumbled or fallen out
- Mastic that needs renewing before redecorating
Frames and glazing around Northbrook
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.
Homes close to Church of St Mary include some older properties, and frames set in older brick or stone need a sealant that suits the wall as well as the frame. For landlords with property near Micheldever station, any sash windows need sound mastic to keep draughts and rain out.
Northbrook is about 7 miles north of Winchester, in Hampshire. Wherever you are in the SO21 postcode area, our applicators can take on sand mastic. Northbrook is one of 683 places in Hampshire where we work. There’s also a page for Southampton, about 17 miles away.
Work in SO21 is quoted and booked the same way as anywhere else. Neighbouring places we cover for sand mastic include Micheldever (1 mile south-east), Stoke Charity (1 mile west), Hunton (2 miles west), Micheldever Station (2 miles north) and East Stratton (2 miles east). We also work in nearby towns such as Basingstoke (11 miles north-east), Winchester (7 miles south), Eastleigh (13 miles south), Andover (10 miles north-west), Chandler's Ford (13 miles south-west) and Alton (13 miles east).
Local landmarks in Northbrook
Locally, jobs take us to homes and businesses close to Half Moon and Spread Eagle pub, among other places. Northbrook’s nearest station is Micheldever station, about 2.1 miles north of the centre.
About our sand mastic in Northbrook
We work across Northbrook renewing sand mastic on sash windows and doors. Every joint is cleaned out and filled by hand for a neat, traditional finish. If you have old cement repairs round a window that have failed and silicone on a period window that looks wrong, we can help.
In a village or hamlet like Northbrook, older cottages and farmhouses often have timber windows set in stone or brick. Older buildings like these do not always suit modern silicone, and sometimes a traditional sand mastic is the better choice.
We stand behind the work with a one-year guarantee, so you’re covered after we’ve gone.
- Where
- Northbrook (SO21)
- Wider area
- Hampshire
- Cover
- 12 months on all our work
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Leave it or put it right?
New sash windows are a major, costly change and on a listed home, consent may be needed. If the frames are sound, renewing the mastic deals with gaps and draughts at the surround. Older cottages and farmhouses around Northbrook can have timber floors and frames, and water through a failed joint can rot timber if it’s left.
Doing several joints on one visit generally makes better use of the time than several visits, so tell us about everything that needs sealing. We’ll give you a clear price for the lot.
Why us?
- We leave the area clean and tidy
- Over 20 years’ experience
- Domestic, commercial and hotel work
- An ARBOMaster approved applicator
Honest limits
Before you book, it’s worth knowing the limits too:
- Sashes that need overhauling
- Masonry that needs repairing
- Cracked or broken glass
If in doubt, phone 0345 464 0079 or drop us an email and we will say what we think.
Surfaces we seal
- Stone surrounds
- Timber door frames
- Tenement windows
- Brick reveals
- Sash and case windows
- Period & listed homes
Nearby places to Northbrook
Other services in Northbrook
Signs you need sand mastic in Northbrook
Shallow joints are a common cause. Mastic that’s too thin cracks and drops out, which is why we pack deep voids first and get the depth right.
People normally contact us after spotting something like this:
- Silicone on a period window that looks wrong
- Mastic round period door frames that has failed
- Mastic worn away on windows facing the weather
- Draughty sash windows at the surround
If you look after a building such as Micheldever CofE Primary School, larger buildings have plenty of frames, and the mastic around each one ages.
What to look for in a quote
- Whether all the old sealant comes out first
- Which colour the sealant will be
- The length of the guarantee
- What the quote includes, VAT included or not
Questions from Northbrook
Do you cover Northbrook for sand mastic?
Yes, Northbrook is within the area we cover. Our work covers London and the South East. You can ring 0345 464 0079 or email us and tell us what needs doing.
Will you come out to Northbrook?
Yes, smaller places are covered as well as towns. We work across London and the South East. Just mention lanes, gates or anything else about the route when you book.
Do you guarantee sand mastic work?
Our 12-month guarantee applies to all our work.
Which is right for my windows, sand mastic or modern sealant?
It depends on the window. On many period windows, sand mastic looks right and suits the building, while modern frames normally get a flexible sealant.
What is sand mastic?
Sand plus a binder based on linseed oil. It’s applied by hand and finished to sit neatly against the masonry.
Is it worth trying it myself?
Some simple jobs can be done by a careful DIYer. Most DIY failures come from sealing over old material, wet joints or too much sealant.
Is it OK to seal over old sealant?
No. The old sealant always comes out first, so the new joint bonds to clean surfaces.
Do you have insurance?
Yes. We’re fully insured, with over 20 years’ experience in sealant work.
Quotes for sand mastic in Northbrook
You’ll get a clear quote before any work starts. It’s based on:
- How many rooms, windows or areas are involved
- Access and height
- The product the joint needs
- Any working-time requirements on site
A few things move the cost up or down: how much old sealant there is and how stubborn it is, any mould to treat, and whether the work is at height. Your quote takes all of that into account.
What we need to know
To help us quote quickly, let us know:
- Where the job is, and your postcode
- Whether it’s a home or a business
- Access, such as stairs, a lift or height
- Any previous sealing or DIY work
For a quick quote, get us on the phone, or email us if that is easier. Describe what needs sealing and we will explain what’s involved and give you a clear price.
Looking after it afterwards
Aftercare is simple:
- Keep sills and gutters clear so water drains away
- Renew mastic before redecorating the windows
- Ask a joiner to look at soft timber first
- Check with your local planning authority if your home is listed
Do not touch or press the mastic while it hardens. It skins over quickly but needs longer to fully harden.
Renewing mastic before redecorating saves doing it twice. Painting over failed mastic hides the problem for a while.
Should I try it myself first?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and does not move well, and the joint depth matters as much as the finish.
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it peels away and traps moisture behind it. Everything old must be removed first.
How it works
Our applicators work methodically: protect, prepare, seal, tidy. For most jobs that takes a few hours for a single window, longer for several. In a small place like Northbrook, access is normally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We check each window surround and the condition of the joint.
- The joint is raked out and cleaned.
- Large voids are packed out.
- New sand mastic is applied and shaped by hand.
- The finish is dressed neatly.
Preparing for the visit
- Mention if the joints have been sealed before
- Plan for the work area to be out of bounds to pets and children
- Tell us if parking is tricky
How to get a quote
Quotes start with a quick conversation. Describe the problem, the location and the size of the job, and we will talk you through what we’d do. When it suits you, phone 0345 464 0079 or send us an email.