Hampshire · England
Window & door mastic in Portmore, Hampshire
Mastic around window and door frames, sills and patio doors for householders, landlords and businesses in Portmore. Fully insured, ARBOMaster approved and guaranteed for a year.
- Cracked sealant at the sill ends
- A bead that does not match the frame
- Gaps between the frame and the inside reveal
How we handle window mastic in Portmore
Behind a thin line of old mastic there’s sometimes a deep void. Filling it with sealant alone leaves a joint that can’t move properly, so we fit backing rod to set the right depth. That way the new bead bonds to the frame and the wall only. We’re often asked to deal with old mastic that has gone black or come away and untidy mastic left by window fitters, on uPVC windows, timber windows & doors and composite doors.
Outdoor sealant needs dry, clean surfaces, so work on frames around Portmore is planned for dry weather. Let us know about access to all the frames, upstairs ones included.
We stand behind the work with a one-year guarantee, so you are covered after we have gone.
- Location
- Portmore (SO41)
- Region
- Hampshire
- Guarantee
- One year on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Different surfaces, different methods
uPVC windows
We clean the frame edge carefully so the plastic isn’t marked, then the sealant goes in between frame and wall and tooled smooth.
Timber windows & doors
Older timber windows in stone or brick can suit sand mastic rather than modern sealant. We can talk through the options.
Landlords, agents and businesses in Portmore
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements.
In hotels, rooms out of use cost money, so we plan the work room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
Keeping the joints in good condition
How long the joints last depends on use and care. Here’s what we suggest:
- Wash the frames with mild soapy water
- Keep drainage slots and sill grooves clear
- Don’t aim a pressure washer at the joints
- Do not paint over the silicone
Check the drainage slots in the frames are not blocked, so rain drains out rather than building up at the sealant.
Leaks usually show up in wet, windy weather, but sealant goes on best when frames and walls are dry. Sorting cracked mastic early means the joint is sound before the bad weather.
Window mastic in Portmore: local notes
Portmore is within about 1 mile of the coast, where wind-driven rain is a fact of life and, nearer the shore, so is salt air. That’s hard on the mastic around window and door frames, especially on the side facing the sea. Historic houses like Beaulieu Palace House (about 4.5 miles north-east) are a reminder that the area around Portmore has older buildings as well as new. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic.
Managing a site like Southlands School? Then the mastic around its windows and doors needs looking after like any other building’s. Rented homes near Lymington Town station change hands often, and renewing tired window mastic between tenants heads off draught and damp complaints.
Portmore is about 2 miles north-east of Lymington, in Hampshire. Jobs in Portmore get the same care as everywhere else we work: old sealant removed completely, careful preparation and a one-year guarantee. Portmore is one of 683 towns and villages in Hampshire we cover. Southampton is on our list too, around 11 miles away.
Here we cover the SO41 postcode area for window mastic. Streets in the area include Warborne Lane, Jordans Lane and Main Road, and we cover them all. If you’re just outside Portmore, we cover Warborne (1 mile west), Pilley (1 mile north-west), Bull Hill (1 mile north), Pilley Bailey (1 mile north) and Walhampton (1 mile south). Further out, we also cover Eastleigh (15 miles north-east), Fareham (15 miles east), Totton (10 miles north), Hedge End (14 miles north-east), Romsey (15 miles north) and Hythe (8 miles north-east).
Near you in Portmore
Locally, jobs take us to homes and businesses close to William Gilpin Church of England Primary School, Priestlands School and Walhampton Arms and the streets around them. The nearest railway station is Lymington Town station, about 1.1 miles south-west. Nearby you will also find Lymington New Forest Hospital (1 mile south-west) and Yarmouth Castle (4.8 miles south). Open spaces near Portmore include Boldre Foreshore.
What sealant work can’t fix
Before you book, it’s worth knowing the limits:
- Penetrating damp from a failed cavity tray or render
- Broken hinges, locks or handles
- Misting between the panes of a double-glazed unit (that needs a new unit)
Not sure which it is? You can call 0345 464 0079 or send us an email and we will tell you honestly before booking.
What we seal
- Aluminium frames
- Timber windows & doors
- Window sills
- uPVC windows
- Composite doors
- Patio & French doors
When to call us in Portmore
Mastic ages in the weather. Sunlight dries the surface out, until it loses its stretch and starts to crack.
It’s worth asking for a quote if you see:
- Rain getting in at the frame or under the sill
- Cold air getting in at the frame edge
- Rushed sealant from a window installation
- Draughty joints inside around the window
If you live in an older home near Saint Nicholas Chapel, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Comparing quotes
- Is VAT in the price?
- Whether the sealant suits the joint
- What insurance they hold
- How the joint is cleaned and prepared
What we do, step by step
On the day, we start by going over the job with you, so you know exactly what we are doing. Surfaces next to the work are protected before we start. Most jobs take a few hours for a few frames, or a day or more for a whole house. Somewhere as small as Portmore, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We check how each frame can be reached safely.
- Old, cracked mastic is removed completely, along with any loose debris.
- The surfaces are cleaned and left dry.
- Backing rod fills deep voids and the sealant goes in on top.
- We tool the joint so water runs off, then clear up.
Preparing for the visit
- Tell us about access, such as stairs, a lift or high-level joints
- Mention any sign-in or site rules at work premises
- Tell us about any water getting in
Get a quote
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints, and email pictures if that’s easy.
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Places near Portmore
Other services in Portmore
Portmore: your questions answered
Will you come out to Portmore?
Yes, we do. Our work covers London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
Do you work for landlords with property near Lymington Town station?
Yes. We work for landlords and agents as well as householders, and several properties can be quoted together. Just ring 0345 464 0079 or drop us an email with the address and what needs doing, and we will give you a clear quote.
Where is Mr Mastic based?
We are a Crawley-based firm. We work across South East England, London and Scotland.
Can you do the inside joint as well?
Yes, we do both. Inside, the joint between frame and plaster is sealed neatly.
Will you leave a mess?
Very little: the area around the joints is protected first, and we clear up the old sealant and our materials before we leave.
Are you ARBOMaster approved?
Yes. We’re approved under the ARBOMaster scheme, the approved applicator scheme for Arbo sealants.
Can you do several jobs on one visit?
Yes, and it often makes sense. Combining jobs makes good use of the visit.
Is the work guaranteed?
Yes. All our work carries a 12-month guarantee, and we’re ARBOMaster approved applicators.
How we quote for window mastic
You will get a clear quote before work begins. It’s based on:
- Whether there’s mould to deal with
- Any working-time requirements on site
- The product the joint needs
- The amount of work
We don’t show prices on the website, because the cost depends so much on the job itself. For a quick quote, please call 0345 464 0079 or send us an email and we’ll talk you through it.
Helping us quote
There’s no need for technical detail. Just tell us:
- Whether it has been sealed before
- The address or postcode of the job
- If it’s domestic, commercial or a hotel
- The problem you’ve noticed
For a quick quote, get us on the phone, or send an email if you’d rather. Describe what needs sealing and we’ll explain what’s involved and send you a clear quote.