Kent · England
External Mastic in Forstal
Sealing brickwork movement joints, render, cladding and façade joints in Forstal, with a 12-month guarantee on every job. Ask us for a quote.
- Rain getting behind render or cladding at a joint
- Brick movement joints where the sealant has split
- Old sealant gone brittle and cracked
External mastic in Forstal
Short cuts in external joints show up within a season or two. New sealant over old, joints packed with mortar and beads with no backing all tend to fail early. We strip the joint back and start again. We work on joints between brick and frames, brickwork movement joints and concrete & block, and people most often call us about moss and dirt in joints with no sealant left and rain getting behind render or cladding at a joint.
In a village or hamlet like Forstal, older cottages and farm buildings often stand in the open, so walls and rooflines take the full force of wind and rain. Gutter joints and wall joints there need a sealant that can flex and stay put.
Each job carries a 12-month guarantee, whatever its size.
- Where
- Forstal (ME20)
- Region
- Kent
- Guarantee
- A year, on every job
- Price
- A clear quote up front
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Do you need external mastic in Forstal?
Using the wrong sealant is another common reason. A stiff, general-purpose sealant can’t cope with a joint that moves a lot, so it pulls away from the edges.
People generally contact us after spotting something like this:
- Rain getting behind render or cladding at a joint
- Joints pointed up with cement by mistake
- Leaking joints around cladding and façade panels
- Joints with sealant missing in places
For site and facilities teams at buildings such as St Peter's Church of England Primary School, its movement joints, gutters and trims need looking after like any other building’s.
Comparing quotes
- How the colour is chosen
- Whether VAT is included
- How hidden problems are handled
- What the cure time is
Honest limits
We’ll always be straight with you, so here’s what new sealant won’t do:
- Structural movement, which needs a surveyor or engineer
- Loose or hollow render, which needs re-rendering
- Walls that need new movement joints cut into them
If in doubt, call 0345 464 0079 or email us and we will say what we think.
Joints and surfaces we work on
- Joints between brick and frames
- Brickwork movement joints
- Façade panels
- Render & cladding joints
- Concrete & block
- Copings & trims
FAQs for Forstal
I let a flat near Aylesford station. Can you help?
Yes, we work for landlords and letting agents. You can call 0345 464 0079 or drop us an email with the address and a few details, and we’ll give you a fixed price before we start.
Is Forstal in your area for external mastic?
Yes. Our work covers London and the South East, and Forstal is part of that. You can phone 0345 464 0079 or email us and tell us what needs doing, and we will give you a clear quote.
Is it OK to fill a movement joint with cement?
No. Cement or mortar cannot stretch, so the joint stops doing its job. If it has already been filled, we can usually cut it out and reseal it.
Can I add another job to the visit?
Yes, and it often makes sense. Combining jobs makes good use of the visit, so mention them when you ask for a quote.
Where is Mr Mastic based?
We work from Crawley. We cover Forstal and the rest of Kent.
How much does external mastic cost in Forstal?
The cost depends on the size of the job, access and how much old sealant has to come out. Ask us for a quote.
Is it worth trying it myself?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. Most DIY failures come from sealing over old material, wet joints or too much sealant.
Are you an approved applicator?
Yes. We are approved under the ARBOMaster scheme, the approved applicator scheme for Arbo sealants.
How the job changes by surface
Joints between dissimilar materials
Each side of the joint may need its own preparation. We prepare both faces so the sealant bonds properly.
Copings and trims
Metal and stone copings both move with temperature, so a flexible sealant suits them best year round.
Can I do it myself?
The biggest DIY mistake is sealing over old sealant. Silicone doesn’t stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
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.
Leave it or put it right?
A failed movement joint lets water into the wall, behind render and cladding. Resealing early keeps the job to the joint itself, instead of the wall and finishes around it. In a small place like Forstal, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
Combining jobs into one visit usually makes better use of the time than several visits, so tell us about everything that needs sealing. We’ll send you a clear quote for the lot.
Why book with us
- Sealant colour chosen to suit
- Neat joints and a tidy finish
- Approved under the ARBOMaster scheme
- Homes, businesses and hotels
Read what affects the cost and what customers say.
How it works
At the end, we look at the finished work together. The visit itself usually takes a few hours to a few days, depending on the length of joint and the access, depending on how much there is to do. Somewhere as small as Forstal, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- Joint faces are cleaned back and primed if the sealant needs it.
- We fit closed-cell backing rod to control the depth.
- The exterior sealant is applied, tooled and checked along its length.
Preparing for the visit
- Plan for the work area to be out of bounds to pets and children
- Mention if the joints have been sealed before
- Mention any sign-in or site rules at work premises
Ask for a quote
For a quick quote, get us on the phone, or send an email if you’d rather. Tell us about the joints that need doing and we’ll explain what’s involved before giving you a price.
Related advice
Also in Forstal
What affects the quote in Forstal
We quote each job individually. These are the things that affect it:
- How much old sealant there is and how hard it is to remove
- How easy the joints are to reach
- Working hours on commercial sites
- The size of the job
Some things make a job bigger or smaller: how much old sealant there is and how stubborn it is, whether mould needs treating, and whether the work is at height. We take all of that into account in your quote.
Asking for a quote
When you contact us, these details help:
- The address or postcode of the job
- How we’d reach the joints
- What’s wrong with the joints now
- If someone has resealed it before
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is, and we will explain how we’d tackle it. When it suits you, call 0345 464 0079 or drop us an email.
External mastic in Forstal: local notes
With historic houses such as Starkey Castle (about 4.4 miles north) nearby, there’s older building stock in the area around Forstal as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. 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 Aylesford station? Then split movement joints are easy to miss on a rental until damp shows inside. In the older streets around Methodist Church Including Sunday School, an extension built onto an older house moves differently, and the joint between them takes the strain.
Forstal is about 3 miles north-west of Maidstone, in Kent. Anywhere in ME20, we cover external mastic for homes and businesses. Our area takes in 922 places across Kent, from the larger towns to small villages. We also work in London, around 29 miles away.
All of ME20 is covered for external mastic. If you need external mastic at a property on Beddow Way and Forstal Road or anywhere close by, our applicators can take on the job. Neighbouring places we cover for external mastic include Pratling Street (1 mile north-east), Eccles (1 mile north-west), New Hythe (2 miles west), Burham (2 miles north) and Larkfield (2 miles west). Within a short drive, we also cover Maidstone (3 miles south-east), Sittingbourne (11 miles east), Dartford (15 miles north-west), Sevenoaks (13 miles west), Royal Tunbridge Wells (15 miles south-west) and Gravesend (10 miles north-west).
Local landmarks in Forstal
In Forstal, that means homes and buildings near Aylesford School, The Bush pub and Tyland Barn, among other places. The nearest railway station is Aylesford station, about 1.2 miles west of the centre. Nearby you will also find Medway megaliths (1 mile north) and Maidstone Hospital (2 miles south). Green spaces nearby include Boxley Hills and Burham Down.