Hertfordshire · England
Sand mastic for sash & case windows in Croxley Green, Hertfordshire
Our applicators work in Croxley Green on traditional burnt sand mastic around sash and case windows and doors in stone and brick. Old sealant removed completely, joints prepared properly.
- Window mastic to renew ahead of painting
- Wind and rain getting in round a sash window
- A silicone bead on a sash window that spoils the look
How we handle sand mastic in Croxley Green
Silicone on a period window often looks wrong and is not always the right material. Sand mastic is the traditional choice, and we can replace one with the other. Common call-outs are for old sand mastic that has cracked, crumbled or fallen out and cement or filler used on old window joints that has cracked, across stone surrounds, brick reveals and period & listed homes.
Outdoor sealant needs dry, clean surfaces, so work on frames around Croxley Green is planned for dry weather. Let us know about access to all the frames, upstairs ones included.
You get a 12-month guarantee, the same in Croxley Green as everywhere else we work.
- Where
- Croxley Green (WD3, WD18)
- Region
- Hertfordshire
- Cover
- A year, on every job
- Price
- A clear quote up front
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Croxley Green homes and the weather
With historic houses such as Chenies Manor House (about 4.2 miles north-west) nearby, there’s older building stock in the area around Croxley Green as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window. Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
For an older house near a landmark such as St Oswald's Parish Church, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint. If you let a flat or house near Rickmansworth station, cracked sand mastic around sash windows lets in the draughts tenants complain about. Schools such as Harvey Road Primary School are buildings too, and the mastic around its windows and doors needs looking after like any other building’s.
Croxley Green is about 1 mile north-east of Rickmansworth, in Hertfordshire. Jobs in Croxley Green get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Our Hertfordshire coverage runs to 381 places, and Croxley Green is one of them. We also work in London, around 18 miles away.
Work in WD3 and WD18 is quoted and booked the same way as anywhere else. Sand mastic is available to properties on New Road, Harvey Road and Bateman Road. Neighbouring places we cover for sand mastic include Holywell (1 mile east), Rickmansworth (1 mile south-west), Batchworth (1 mile south-west), Chorleywood West (2 miles west) and Moor Park (2 miles south). Within a short drive, we also cover Hemel Hempstead (7 miles north), St Albans (9 miles north-east), Welwyn Garden City (15 miles north-east), Harpenden (12 miles north), Hatfield (12 miles north-east) and Borehamwood (7 miles east).
Around Croxley Green
Typical jobs here are in homes near Croxley Danes School, Rickmansworth School and The Red House, among other places. For rail, the closest station is Rickmansworth station, roughly 1.3 miles west of the centre. Nearby you’ll also find Hertfordshire Fire Brigade Museum (2.4 miles east) and Hilfield Castle (4.7 miles east). Not far away are Chorleywood Common and Tumbling Bay.
Nearby places to Croxley Green
More services for Croxley Green
What affects the cost of sand mastic
For a quick quote, just ask. What matters most is:
- Whether old sealant or filler has to be cut out
- Any mould that needs treating
- How many areas need sealing
- How much there is to do
Instead of a standard rate, we price the job in front of us: the amount of work, the old material and the access. You will know the price before we begin.
What to tell us for a quote
To make quoting easier, please include:
- The address or postcode of the job
- How we’d reach the joints
- The rough size of the job
- What the problem is, such as mould, gaps, leaks or cracking
A good description makes for an accurate quote. Tell us where the job is, what’s wrong and how much there is.
Different surfaces, different methods
Period and listed homes
On a listed home or in a conservation area, the right material matters. Sand mastic is often the preferred finish.
Timber door frames
Round a period front door, sand mastic gives the right look.
What sealant work can’t fix
We will always be straight with you, so here’s what new sealant won’t do:
- Timber that has rotted
- Planning or listed building consent (your local planning authority decides)
- Cracked or broken glass
If in doubt, phone 0345 464 0079 or email us and we will say what we think before you book.
What we seal
- Timber door frames
- Sash and case windows
- Period & listed homes
- Stone surrounds
- Tenement windows
- Brick reveals
Croxley Green: your questions answered
Can you help a landlord with a rental near Rickmansworth station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. You can ring 0345 464 0079 or send us an email with the details for a clear quote.
Do you cover Croxley Green for sand mastic?
Yes. We work across London and the South East, and Croxley Green is part of that. You can ring 0345 464 0079 or send us an email and tell us what needs doing.
Can old silicone round a sash window be swapped for sand mastic?
In most cases. The silicone is cut out and the joint cleaned, then point it with sand mastic.
How long does sand mastic take to harden?
It forms a skin fairly soon and it hardens fully over a longer time. The weather and joint depth both affect it.
What do you put in the joint?
We choose the sealant for the joint, not the other way round. Movement, water and weather all affect the choice.
What information do you need?
The location, the problem and the rough size of the job. If you can, email a few photos.
Can you seal over the old sealant?
No. We remove every bit of old sealant first, so the new joint bonds to clean surfaces.
What does sand mastic cost?
We do not publish prices, because the cost depends on the job: its size, the old material, access and the product needed. We agree the price before any work begins.
Why deal with it now?
A silicone bead can be quicker, but on period stone or brick it often looks out of place. Sand mastic is the traditional material and finishes neatly against the masonry. In a small place like Croxley Green, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
Leaving a failed joint normally makes the job bigger, not smaller. If you’re unsure, phone 0345 464 0079 or send us an email and we will give you an honest view and a quote.
Why book with us
- Quality sealants from Arbo and Everbuild
- We leave the area clean and tidy
- Experience in homes, commercial sites and hotels
- One-year guarantee on every job
Read what affects the cost and customer reviews.
How the visit works
You do not need to clear the whole room or building, just the space around the work. Everything nearby is protected, and the work takes a few hours per window, depending on the condition of the joints for a typical job. Somewhere as small as Croxley Green, access is often the only tricky part. 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.
- We fill deep gaps so the new mastic isn’t too thick.
- New sand mastic is applied and shaped by hand.
- We finish the mastic to a tidy line.
How to prepare
- Let us know about stairs, lifts or work at height
- Let us know about earlier repairs to the joints
- Mention any sign-in or site rules at work premises
Getting a quote
Need a quote? Please call 0345 464 0079 or drop us an email and tell us about the job. You’ll know what we plan to do, and what it will cost, before any work begins.
Advice
For landlords and businesses
Housing providers, facilities teams and property managers book us too. Several sites can be quoted together.
Businesses can book us for washrooms, kitchens, offices and more. For commercial premises, we can talk through working times when we quote.
Keeping the joints in good condition
A little care helps the new joints last. Our advice:
- Check the mastic when you check the paintwork
- Make sure water runs off the sill
- Ask the planning authority about consent for listed or conservation-area homes
- Get any rot dealt with first
Check the mastic when you check the paintwork. Catching cracks early keeps repairs small.
Gaps round a sash box let in draughts and rain. The longer it’s left, the more the joint opens.