Hertfordshire · England
Sand mastic for sash & case windows in High Cross, Hertfordshire
Sand mastic for High Cross and the surrounding area: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Gaps where the frame meets the masonry
- Old sand mastic that has cracked, crumbled or fallen out
- Patchy fillers round a sash window
Looking after it afterwards
Good habits help new joints last longer. Our tips:
- Ask the planning authority about consent for listed or conservation-area homes
- Ask us before painting near the mastic
- Check the mastic when you check the paintwork
- Avoid heavy scraping on the mastic joint
Do not run silicone over the new mastic. If anything cracks, get it looked at rather than patching it.
Sound mastic protects the frame. Once it fails, water can sit against the timber and timber that stays wet can rot.
Sand mastic for homes and businesses in High Cross
If your home is listed or in a conservation area, check with your local planning authority whether consent is needed for work to windows. Sand mastic is often favoured as a like-for-like material. We work on brick reveals, period & listed homes and sash and case windows, and common reasons people get in touch are tired mastic found when preparing windows for paint and cracked mastic round a front door frame.
Mastic can only go onto a dry, clean joint, so window work in High Cross is booked around the forecast. Let us know about access to all the frames, upstairs ones included.
Big or small, it’s backed by our one-year guarantee in High Cross and across Hertfordshire.
- Place
- High Cross (SG11)
- Wider area
- Hertfordshire
- Cover
- 12 months on all our work
- Quotes
- A clear quote up front
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Why it’s worth doing now in High Cross
If you are redecorating, renew the mastic first. Paint over cracked mastic will not stop the gaps and traditional guidance is to leave the new mastic unpainted. Older cottages and farmhouses around High Cross can have timber floors and frames, and water through a failed joint can rot timber if it’s left.
We do not show prices on the website, because the cost depends so much on the job itself. For a quick quote, please ring 0345 464 0079 or email us.
Why High Cross customers choose us
- Over 20 years’ experience
- Anti-fungal silicone where joints get wet
- Tidy, careful work
- We never seal over old sealant
Take a look at how sealant jobs are priced or our reviews.
Should I try it myself 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.
If you’ve already had a go yourself, that is fine. We remove it and do the joint properly, so just mention it when you contact us.
Sand mastic in High Cross: local notes
Historic houses like Much Hadham Palace (about 4.2 miles east) are a reminder that the area around High Cross has older buildings as well as new. Where a home is older, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic. Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
In the older streets around Church of St John the Evangelist, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint. Letting a property close to Ware station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about. If you look after a building such as Thundridge Church of England Primary School, larger buildings have plenty of frames, and the mastic around each one ages.
High Cross is about 2 miles north of Ware, in Hertfordshire. Whether you are in the middle of High Cross or further out, sand mastic is available for homes and businesses alike, from flats and houses to offices and hotels. High Cross is one of 381 places in Hertfordshire where we work for sand mastic. For nearby work, see our Chelmsford page, about 23 miles away.
Jobs for sand mastic in SG11 works the same way as everywhere else we cover. Whether your property is on North Drive, Chestnut Grove and Poplar Close or anywhere close by, we can help. Close by, we work in Wadesmill (1 mile south-west), Standon Green End (1 mile north), Thundridge (1 mile south), Cold Christmas (1 mile south-east) and Barwick (1 mile north-east). Larger places within reach include Stevenage (8 miles north-west), St Albans (15 miles south-west), Bishop's Stortford (8 miles east), Welwyn Garden City (8 miles south-west), Harpenden (14 miles west) and Hitchin (13 miles north-west).
What’s near High Cross
We work in homes and buildings around The White Horse Inn. For rail, the closest station is Ware station, about 2.8 miles south of the centre. Nearby you’ll also find Museum of Street Lighting (3.4 miles south) and Hertford County Hospital (4.6 miles south-west). For a walk, there’s King's Meads.
Questions from High Cross
Can you do sand mastic in High Cross?
Yes. We work across London and the South East, and High Cross is part of that. Just ring 0345 464 0079 or send us an email with a few details of the job, and we’ll give you a clear price.
I let a flat near Ware station. Can you help?
Yes, rental work is part of what we do. Just ring 0345 464 0079 or drop us an email and tell us about the property, and we’ll give you a clear price.
What is sand mastic?
Sand mastic is a traditional material for pointing round windows and doors. It combines sand with a linseed-oil-based binder.
Are you an approved applicator?
Yes. We hold ARBOMaster approved applicator status and we’re fully insured too.
Do you do commercial work?
Yes. We have worked for hotels, offices and other businesses and we are fully insured.
Will you leave a mess?
No. The area is protected while we work and cleaned up afterwards.
Should I check with the council before work on a listed or conservation-area home?
Your local planning authority is the one to ask. They’ll tell you if consent is needed.
Are you fully insured?
Yes, we’re fully insured for every job we do.
What affects the cost of sand mastic
Call for a quick quote. What matters most is:
- The amount of work
- Any working-time requirements on site
- Whether old sealant or filler has to be cut out
- Whether the work is at height
A failed joint rarely gets cheaper to fix by waiting, as water and mould keep getting in. If you are unsure, phone 0345 464 0079 or send us an email for an honest opinion and a quote.
What we need to know
Photos help, but a description is a good start. Try to tell us:
- The type of property
- Where the job is, and your postcode
- Any previous sealing or DIY work
- What’s wrong with the joints now
There’s no standard price list, because every job is different. Instead, your job gets its own clear quote. To arrange one, ring 0345 464 0079 or email us.
What the job involves on each surface
Timber door frames
Doors face weather and wear, so their mastic can fail sooner. We rake it out and renew it.
Sash and case windows
Sash windows are where we do most sand mastic work. Each joint round the box is raked out and renewed.
Towns and villages near High Cross
Also in High Cross
The process
The work is kept neat and contained to the area we’re working on, so you can carry on as normal. Expect the work to take a few hours per window, depending on the condition of the joints, and we tell you how long to leave it before we go. Somewhere as small as High Cross, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- First we agree which joints need doing.
- Old mastic and any loose material are raked out.
- We pack any deep voids first.
- The sand mastic is mixed and pressed into the joint by hand.
- We dress the finish so it sits neatly against the masonry.
Before we arrive
- For indoor joints, keep the area dry beforehand if you can
- Tell us about any previous sealing or DIY attempts
- Tell us about access, such as stairs, a lift or high-level joints
Ask for a quote
We quote each job on its own, so start by telling us what you need. Simply phone 0345 464 0079 or send us an email and describe the job, and photos are welcome.
Read more
When something else is needed
We will not take on work that will not last, so here’s what sealant can’t put right:
- Timber that has rotted
- Broken panes
- Planning or listed building consent (your local planning authority decides)
Not sure which it is? You can call 0345 464 0079 or send us an email and we’ll tell you honestly.
Joints and surfaces we work on
- Tenement windows
- Period & listed homes
- Timber door frames
- Sash and case windows
- Stone surrounds
- Brick reveals