Hertfordshire · England
External & façade joints in Frogmore, Hertfordshire
External mastic in Frogmore from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Moss and dirt in joints with no sealant left
- Joints with sealant missing in places
- Failed sealant between panels on a façade
External mastic for homes and businesses in Frogmore
For buildings in Frogmore, we reseal external joints of all kinds, from brick movement joints to cladding panels. Every joint gets the same careful preparation: clean joint faces and the right depth. Common call-outs are for brick movement joints where the sealant has split and movement joints filled with mortar instead of sealant, across joints between brick and frames, façade panels and brickwork movement joints.
External sealant needs dry, clean surfaces, so work around Frogmore is planned for dry weather. Tell us about access to all sides of the building, including outbuildings and garages.
The work is covered for a year after we finish. If anything isn’t right with it, ring 0345 464 0079 or email us.
- Place
- Frogmore (AL2)
- Wider area
- Hertfordshire
- Guarantee
- A year, on every job
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Your questions about external mastic in Frogmore
Can you do external mastic in Frogmore?
Yes, Frogmore is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or email us and let us know what needs doing.
Do you work for landlords with property near How Wood station?
Yes, we work for landlords and letting agents. You can ring 0345 464 0079 or send us an email with the address and a few details, and we’ll give you a fixed price before any work starts.
Is it OK to fill a movement joint with cement?
No. Cement or mortar cannot stretch and the joint fails. Where a joint has been mortared, it can often be raked out and sealed properly.
Do you have insurance?
Yes. We are fully insured for domestic and commercial work.
What sealant do you use?
Each joint gets the product that suits it. Where it moves, gets wet or faces the weather makes a difference, and we will explain our choice.
How long does the job take?
As a guide, most jobs take a few hours for a handful of joints, longer for a whole elevation. Larger jobs naturally take longer.
Will the new joint stand out?
There’s a good range of exterior colours, including greys, browns, whites and stone tones. We pick the one that suits your wall best so it doesn’t stand out.
Are you ARBOMaster approved?
Yes. Mr Mastic is an ARBOMaster approved applicator and we’re fully insured too.
When it is not the sealant
A few problems are outside what sealant work can do:
- Cracking across the wall rather than at a joint
- Failed render or damaged cladding panels
- Movement that is more than a sealant joint can take
Not sure which it is? You can call 0345 464 0079 or email us and we’ll tell you honestly before you book.
What we seal
- Concrete & block
- Brickwork movement joints
- Façade panels
- Copings & trims
- Render & cladding joints
- Joints between brick and frames
Frogmore buildings and the weather
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. With historic houses such as High Elms Manor (about 2.8 miles south-west) nearby, there’s older building stock in the area around Frogmore as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material.
In the older streets around Church of the Holy Trinity, an extension built onto an older house moves differently, and the joint between them takes the strain. If you let a flat or house near How Wood station, failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Frogmore is about 2 miles south of St Albans, in Hertfordshire. We provide external mastic to homeowners, landlords and businesses in Frogmore and the surrounding area, as part of our work across Hertfordshire. Our area takes in 381 places across Hertfordshire. Our London page covers work nearby.
All of AL2 is covered for external mastic, from the main roads to the quietest streets. Local streets include Centaurus Square, Frogmore and Avian Avenue, all of which we cover. Other places close to Frogmore include Park Street (1 mile north-west), How Wood (1 mile west), Colney Street (1 mile south-east), Chiswell Green (1 mile north-west) and Sopwell (1 mile north). Within a short drive, we also cover Watford (5 miles south-west), Hemel Hempstead (6 miles north-west), Stevenage (15 miles north-east), Welwyn Garden City (8 miles north-east), Harpenden (7 miles north) and Hoddesdon (14 miles east).
Local landmarks in Frogmore
Typical jobs here are in homes near The Old Red Lion pub and Marlborough Science Academy and the streets around them. There’s a railway station in Frogmore itself: How Wood station. A little further out are Hypocaust Museum (2.3 miles north-west) and Hilfield Castle (4.5 miles south). Green spaces nearby include Verulamium Lake and Broad Colney Lakes.
Towns and villages near Frogmore
Also in Frogmore
Can I do it myself?
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions, and the work is guaranteed for a year.
What happens on the day
On the day, we look over the joints with you first. We protect the surfaces around the joints before any work starts. Most jobs take a few hours for a handful of joints, longer for a whole elevation. Somewhere like Frogmore needs a little journey planning: tell us about narrow lanes, gates, long drives and where we can park. Everything for the job comes with us, so a second trip is avoided where possible.
- First we look over the joints with you, agree which to renew and talk through access.
- We cut out the failed sealant and rake out any dirt or growth.
- We clean both faces of the joint and prime them where the product calls for it.
- We push in closed-cell backing rod so the sealant is the right depth and bonds to the sides only.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
Getting ready for the visit
- Keep pets and children clear of the area while we work
- For indoor joints, keep the area dry beforehand if you can
- Mention if the joints have been sealed before
Ask for a quote
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is.
Advice
What the job involves on each surface
Joints between dissimilar materials
Joints where frames, sills or panels meet the wall are common leak points. We cut out the old sealant and reseal with a product suited to both surfaces.
Copings and trims
Metal and stone copings both move with temperature, so the joints need a sealant that stays flexible year round.
Why act early in Frogmore
A failed movement joint lets water into the wall, behind render and cladding. Dealing with it early keeps the repair to the joint, rather than the wall around it. Older cottages and farmhouses around Frogmore can have timber floors and frames, where water from a failed joint can cause rot if it’s left.
Leaving a failed joint generally makes the job bigger, not smaller, as water and mould keep getting in. If you are not sure whether it needs doing, phone 0345 464 0079 or drop us an email and we will give you an honest view and a quote.
Why us?
- 4.9 on Google from 180+ five-star reviews
- Experience in homes, commercial sites and hotels
- White, clear, grey or another colour, product permitting
- Colour agreed with you before any work starts
See what affects the cost and our reviews.
For landlords and businesses
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements and we will give you a quote.
Common problems we fix in Frogmore
Using the wrong sealant is another common reason. A stiff, general-purpose sealant cannot cope with a joint that moves a lot, and it tears off the sides.
People normally contact us when they notice something like this:
- Panel joints letting water in
- Movement joints filled with mortar instead of sealant
- Movement joints with cracked, split or missing sealant
- Plants rooting in failed movement joints
Schools such as Park Street Church of England Voluntary Aided Primary School are buildings too, and its movement joints, gutters and trims need looking after like any other building’s.
What to look for in a quote
- What the cure time is
- How the colour is chosen
- How the surfaces are prepared before sealing
- What the quote includes, VAT included or not