Hertfordshire · England
Sand Mastic in Codicote
Traditional burnt sand mastic around sash and case windows and doors in stone and brick in Codicote, with a one-year guarantee on every job. Ask us for a quote.
- Gaps where the frame meets the masonry
- Cement or filler used on old window joints that has cracked
- Window mastic to renew ahead of painting
How we handle sand mastic in Codicote
Across Codicote, we renew sand mastic around sash and case windows. Each joint is raked out, prepared and pointed by hand for a neat, traditional finish. We work on stone surrounds, period & listed homes and sash and case windows, and people most often call us about crumbling sand mastic round a window and gaps between timber frames and stone or brick.
In a smaller place like Codicote, some walls face open ground and catch the full force of the weather. That is hard on the mastic around frames and sills.
Each job carries a 12-month guarantee, large or small.
- Where
- Codicote (SG4)
- Region
- Hertfordshire
- Cover
- One year on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
How it works
On the day, we start by going over the job with you. We protect the surfaces around the joints before we start. The work usually takes anything from a few hours to a full day, depending on how many windows. A visit to Codicote is planned like any other: the time, the access and where to park are agreed in advance. If the work is outside, the weather plays a part, as sealant needs a dry surface.
- First we agree which joints need doing.
- Old mastic and any loose material are raked out.
- We pack any deep voids first.
- We apply the mastic by hand and shape it.
- We dress the finish so it sits neatly against the masonry.
Getting ready for the visit
- Plan for the work area to be out of bounds to pets and children
- Mention any tricky access
- Where the joints are inside, avoid wetting them before we arrive
How to get a quote
It all starts with a short chat. Describe the problem, the location and the size of the job. Whenever you are ready, phone 0345 464 0079 or drop us an email.
Advice
Questions from Codicote
Do you cover smaller places like Codicote?
Yes. Codicote is within the area we cover, which takes in towns, villages and rural addresses. 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 work for landlords with property near Knebworth station?
Yes, we work for letting agents and landlords. You can call 0345 464 0079 or drop us an email with the address and a few details, and we will give you a fixed price before work begins.
Will you leave a mess?
No. We protect the surfaces around the joints, and we tidy up before we go.
Will the old sealant be removed?
Yes. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Is it worth trying 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.
Do I need to be at home?
If the work is inside, we need someone to let us in. Once we have agreed the job, you don’t need to watch us work.
What exactly is sand mastic?
It’s the traditional filler for the joint round timber windows and doors. It combines sand with a linseed-oil-based binder.
Can you replace silicone on a period window with sand mastic?
Yes, we do this often. All the old silicone is removed first so the mastic beds in well.
What sealant work can’t fix
In fairness, some problems need a different trade:
- Decisions on consent for listed homes
- Broken panes
- Sashes that need overhauling
If you are not sure, just phone 0345 464 0079 or email us and we’ll give you a straight answer.
Surfaces we seal
- Timber door frames
- Stone surrounds
- Tenement windows
- Brick reveals
- Period & listed homes
- Sash and case windows
Signs you need sand mastic in Codicote
Shallow joints are a common cause. A thin layer does not hold well so we make sure the new mastic is the right thickness.
The problems people normally mention when they call include:
- Mastic round period door frames that has failed
- Draughts and rain around sash boxes
- Crumbling sand mastic round a window
- Tired mastic found when preparing windows for paint
For site and facilities teams at buildings such as Codicote Church of England Primary School, its window and door frames need their mastic kept sound, just like a home’s.
What your quote should include
- Which sealant they’ll use, and why
- Whether all the old sealant comes out first
- Which colour the sealant will be
- Are they insured?
How we quote for sand mastic
For a quick quote, just ask. The main things that affect it are:
- Access and height
- Working hours on commercial sites
- The size of the job
- Which sealant suits the joint
Every job is a little different, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all play a part.
What to tell us for a quote
The more you tell us, the more accurate the quote. When you get in contact, it helps to mention:
- If it’s domestic, commercial or a hotel
- A few photos by email, if you can
- Any previous sealing or DIY work
- Where the job is, and your postcode
There’s no standard price list. Instead, we give you a clear quote for your job. To get started, phone 0345 464 0079 or drop us an email.
Also near Codicote
Also in Codicote
DIY versus a professional finish
The difference is mostly in the preparation and the product. We take joints back to clean, dry surfaces, and the sealant is chosen for how the joint moves and where it is, then guaranteed for a year.
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 does not work out, we can still put it right.
For landlords and businesses
Water getting past a failed joint can damage the building, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance that we can handle for you.
Landlords and agents in Codicote can book us as well as homeowners. Sealant work between tenants keeps a property looking cared for.
Frames and glazing around Codicote
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. With historic houses such as Shaw's Corner (about 1.7 miles south-west) nearby, there’s older building stock in the area around Codicote as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
If you live in an older home near Parish Church of St Giles, 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 Knebworth station, any sash windows need sound mastic to keep draughts and rain out.
Codicote is about 4 miles north-west of Welwyn Garden City, in Hertfordshire. From the centre of Codicote to the outskirts, we cover sand mastic for every kind of property, from flats and houses to offices and hotels. Our area takes in 381 places across Hertfordshire. We also work in London, around 25 miles away.
Our applicators cover all of SG4 for sand mastic and the streets around it. If you need sand mastic at a property on High Street, Baker's Lane and The Green or anywhere close by, our applicators can take on the job. Nearby, we also carry out sand mastic in Codicote Bottom (1 mile west), Driver's End (1 mile north), Nup End Green (1 mile north-east), Pottersheath (1 mile east) and Ayot St Lawrence (1 mile south-west). We also work in nearby towns such as Watford (15 miles south-west), Hemel Hempstead (12 miles south-west), Stevenage (5 miles north-east), St Albans (8 miles south-west), Welwyn Garden City (4 miles south-east) and Harpenden (5 miles south-west).
Landmarks near Codicote
Typical jobs here are in homes near The Goat Public House, Monk's Walk School and Danesbury Park, among other places. The nearest railway station is Knebworth station, about 2.4 miles north-east of the centre. Nearby you will also find Howard Centre (3.6 miles south) and Queen Elizabeth II Hospital (5 miles south-east). Green spaces nearby include Mardley Heath.
Different surfaces, different methods
Brick reveals
Loose mastic comes out and deep gaps are packed before the new mastic goes in.
Period and listed homes
Materials matter on listed and conservation-area homes. Sand mastic is often the preferred finish.