Hertfordshire · England
Great Gaddesden Sand Mastic
Traditional burnt sand mastic around sash and case windows and doors in stone and brick for Great Gaddesden, backed by a 12-month guarantee. Ask us for a quote.
- Patchy fillers round a sash window
- Failed mastic on an exposed elevation
- A silicone bead on a sash window that spoils the look
How we handle sand mastic in Great Gaddesden
Fresh sand mastic forms a skin quite soon, but it takes longer to harden fully. Traditionally, sand mastic is left unpainted and we’ll advise if you’re redecorating. If you’re dealing with window mastic to renew ahead of painting and draughty sash windows at the surround, we can help.
Mastic can only go onto a dry, clean joint, so window work in Great Gaddesden is booked around the forecast. Let us know about access to all the frames, upstairs ones included.
Our work is backed for twelve months, in Great Gaddesden and everywhere else we cover.
- Where
- Great Gaddesden (HP1)
- Region
- Hertfordshire
- Guarantee
- 12 months on all our work
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
FAQs for Great Gaddesden
Do you work for landlords with property near Berkhamsted station?
Yes, rental work is part of what we do. Just call 0345 464 0079 or drop us an email and tell us about the property, and we will give you a clear price.
Is Great Gaddesden in your area for sand mastic?
Yes, Great Gaddesden is within the area we cover. Our work covers London and the South East. Just phone 0345 464 0079 or email us with a few details of the job.
Can old silicone round a sash window be swapped for sand mastic?
Yes, it’s a common request. All the old silicone is removed first so the mastic beds in well.
What sealant do you use?
We choose the sealant for the joint, not the other way round. Where it moves, gets wet or faces the weather makes a difference.
Do you remove the old sealant?
Yes, always, and completely. New silicone doesn’t stick to old silicone, so any old material comes out before anything new goes in.
What’s sand mastic made of?
Sand mastic is a traditional material for pointing round windows and doors. It’s made with sand and a linseed-oil-based binder.
What guarantee comes with the work?
Our 12-month guarantee covers every job, sand mastic included.
Are you fully insured?
Yes. We’re fully insured, and we can confirm the details when we quote.
Towns and villages near Great Gaddesden
Other services in Great Gaddesden
How it works
When we get to you, we check the joints match what you told us. 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. Somewhere as small as Great Gaddesden, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- First we agree which joints need doing.
- We remove the old, loose mastic.
- Deep gaps are packed so the mastic sits at the right depth.
- The sand mastic is mixed and pressed into the joint by hand.
- The surface is finished to suit the stone or brick.
Preparing for the visit
- Mention any leaks or damp you’ve noticed
- Mention any parking rules near the property
- Mention any sign-in or site rules at work premises
Ask for a quote
For a quote, phone 0345 464 0079 or email us and tell us where the job is and what the problem looks like. You’ll have a clear quote before we start.
Advice
Can I do it myself?
A DIY attempt does not rule out a professional job. We cut it out and start again, so tell us about it when you ask for a quote.
Sealing over old silicone is the commonest DIY error. Silicone doesn’t stick to old silicone, so it peels away and traps moisture behind it. Everything old must be removed first.
Why it’s worth doing now in Great Gaddesden
Before painting the windows, it pays to renew the mastic. Painting over failed mastic doesn’t seal it, and the new mastic is traditionally left unpainted. In a small place like Great Gaddesden, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
Instead of a standard rate, we look at what your job involves: how many joints, what’s in them now and how we reach them. The price is agreed before we begin.
What you get with us
- A 12-month guarantee on all work
- Homes, businesses and hotels
- Over 20 years’ experience
- Fully insured
Take a look at our cost guide or what customers say.
Great Gaddesden homes and the weather
Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Letting a property close to Berkhamsted station? Then older sash windows in a rental need their mastic kept sound to keep the weather out. Schools such as Great Gaddesden Church of England Primary School are buildings too, and its window and door frames need their mastic kept sound, just like a home’s. If you live in an older home near Church of St John the Baptist, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Great Gaddesden is about 3 miles north-west of Hemel Hempstead, in Hertfordshire. Great Gaddesden gets the same service as everywhere we cover: the old material taken out, joints prepared properly and a 12-month guarantee. Great Gaddesden is one of 381 towns and villages in Hertfordshire where we work for sand mastic. We also work in London, around 27 miles away.
Jobs for sand mastic in HP1 is quoted and booked the same way as anywhere else. Streets in the area include Church Meadow, Piper's Hill and Dagnall Road. Close by, we work in Nettleden (1 mile south-west), Frithsden (1 mile south-west), Potten End (2 miles south-west), Fields End (2 miles south) and Ashridge (2 miles west). Larger places within reach include Watford (10 miles south-east), Hemel Hempstead (3 miles south-east), St Albans (8 miles east), Welwyn Garden City (14 miles east), Harpenden (7 miles east) and Hitchin (15 miles north-east).
Local landmarks in Great Gaddesden
Typical jobs here are in homes near John F Kennedy Catholic School and The Crown and Sceptre pub and the streets around them. For rail, the closest station is Berkhamsted station, roughly 3 miles south-west. Nearby you will also find Hemel Hempstead Hospital (3.2 miles south-east). For a walk, there’s Landpark Wood.
How we quote for sand mastic
We don’t publish a price list, because no two jobs are the same. The quote depends on:
- Working hours on commercial sites
- The old material and how stubborn it is
- How easy the joints are to reach
- How many areas need sealing
Leaving a failed joint normally makes the job bigger, not smaller. If you’re unsure, ring 0345 464 0079 or email us for an honest opinion and a quote.
Helping us quote
Before you ask for a quote, have a think about:
- The problem you’ve noticed
- Whether it’s a home or a business
- How many joints, rooms or windows are involved
- Where the job is, and your postcode
Getting a quote is simple: let us know the job and the location. A few photos by email make the job easier to understand, and we’ll come back to you with a quote.
Aftercare tips
So the new joints stay in good condition:
- Look over the window mastic once a year
- Ask the planning authority about consent for listed or conservation-area homes
- Go gently near the mastic when preparing windows
- Ask a joiner to look at soft timber first
Check the mastic when you check the paintwork. Small cracks are easier to deal with early.
Good mastic helps keep the frame dry. Once it fails, water can sit against the timber, which can lead to rot.
Landlords, agents and businesses in Great Gaddesden
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
Whether it’s one flat or a portfolio, you get the same standard of work: the old material taken out, careful preparation and a 12-month guarantee.
What we cannot put right
We will always be straight with you, so here’s what sealant can’t fix:
- Crumbling stone or brickwork round the window
- Sashes that rattle, stick or won’t open
- Planning or listed building consent (your local planning authority decides)
If in doubt, call 0345 464 0079 or send us an email and we’ll say what we think.
Surfaces we seal
- Period & listed homes
- Timber door frames
- Brick reveals
- Stone surrounds
- Sash and case windows
- Tenement windows