Construction and new-build mastic in Cosham, Portsmouth
Looking for construction mastic in Cosham? Send us the details for a fixed quote, backed by a 12-month guarantee on the work.
- Existing joints on a refurb that need cutting out and resealing
- Missed perimeter joints on a new elevation
- Cracks opening in caulked internal joints
Construction mastic in Cosham
Send drawings, photos or a joint schedule, or tell us about the site, and we’ll come back with a fixed quote.
Construction mastic for commercial buildings in Cosham
The programme rarely stands still, so the mastic package has to flex with it. We agree a sequence at the start and adjust it as the site manager releases areas, so applicators arrive when areas are genuinely ready. Sealing too early only means coming back once others have damaged it. We work on cladding and panel joints, window and door perimeters and sanitary and kitchen joints, and what we’re called in for most is external joints sealed in damp or cold conditions that are now failing and oversized or tapered gaps around new frames. For commercial sealant work in Cosham, you deal with one contact from quote to sign-off, whether it’s one building or several.
On a small site around Cosham, the mastic is best done in the fewest visits we can manage. Tell us when scaffold comes down and when decoration finishes, and we will plan around those stages.
Building owners and contractors get the same cover: twelve months on the work we carried out. Faults in the structure, damage and other trades’ work fall outside it, and we say so plainly.
- Place
- Cosham (PO6, PO3, PO2)
- Wider area
- Portsmouth
- Guarantee
- 12 months on every job
- Quote
- Quoted before any work starts
- Phone
- 01277 525 020
- Last updated
- 3 November 2026
What sets the cost
The price varies from site to site. Expect it to depend on:
- Whether the work must be split into stages
- Distance, for remote addresses
- Access and working height
- The site’s rules and procedures
Pricing mastic packages depends on how many there are, their condition and the access, and any specification that applies. Call for a quote.
Before you send an enquiry
Diagnosis starts before we arrive. Let us know:
- How the joints are reached, and at what height
- Any dates the work must fit around
- Whether an asbestos survey exists
- The type of building and who uses it
Quotes are fixed against the scope you send, so you know the figure before anyone is on site. To start the process, ring 01277 525 020 or email the details over.
When something else is needed
We seal joints; we don’t mend everything behind them. On its own, sealant can’t deal with:
- Fire-stopping design or sign-off (that’s for the designer, fire engineer and building control)
- Frames fitted out of tolerance
- Joint design decisions that belong to the architect or engineer
If in doubt, speak to us on 01277 525 020 or email us and we’ll say what we think.
Where we work in Cosham
- Brick and block movement joints
- Internal decorators’ caulk
- Sanitary and kitchen joints
- Cladding and panel joints
- Floor and skirting junctions
- Window and door perimeters
Sites and facades in and around Cosham
Cosham sits close to the coast, within about 1 mile. On a coastal site, facade and perimeter joints face driven rain and, closer to the beach, salt, so we check the specified product suits the exposure before the first bead. Central London is about 62 miles from Cosham. Building activity in the commuter belt runs from new flats near stations to business park refurbishments, and each scheme needs its mastic sealed to programme.
When units on a site such as Oak Park Industrial Estate, 0.7 miles to the west of Cosham, are refurbished or reclad, the panel joints and window perimeters are part of the mastic package. On a healthcare site such as Queen Alexandra Hospital, 0.6 miles to the north of Cosham, new blocks and refurbishments go on while the hospital keeps running, so mastic work is sequenced carefully.
Cosham is about 2 miles south-west of Purbrook, in Portsmouth. Looking for construction mastic in Cosham? We can help, as we do across Portsmouth. Our Portsmouth coverage takes in 19 places, from busy centres to rural villages.
Business premises anywhere in PO6, PO3 and PO2 are within our area. Among the streets we cover are Dean Road, Park Lane and Elgin Road. With the A397 nearby, Cosham is easy to get to with materials and equipment. Close to Cosham, our area also takes in Wymering (1 mile north-west), Hilsea (1 mile south), Drayton (1 mile east), Widley (1 mile north-east) and Paulsgrove (1 mile west). Bigger towns within reach include Southsea (4 miles south), Milton (3 miles south), Landport (3 miles south), Portsea (3 miles south-west), Portsmouth Point (4 miles south-west) and Fratton (3 miles south).
Landmarks near Cosham
Around Cosham, our work takes us to commercial buildings near The First Post pub, Alexandra Park and Springfield School and the streets around them. Cosham has its own railway station: Cosham station. A little further out are Tricorn Centre (2.9 miles south) and World War I Remembrance Centre (1 mile south-east). The countryside around Cosham includes Southmoor Nature Reserve and Portsdown Hill.
FAQs: Cosham
Can you work at a site such as Oak Park Industrial Estate, by Cosham?
Yes, sites like Oak Park Industrial Estate are within our area, along with the rest of Cosham. Photos and a short description are enough for a first look.
Can work at a site such as University of Portsmouth - Langstone Campus fit around teaching?
Yes. We plan campus work around teaching, exams and residence turnarounds. Any paperwork you need, from RAMS to our insurance certificate and CSCS details, is confirmed with the quote.
What will the job cost?
It depends on the job: the volume of work, the access, the specified product and how it’s phased. Call for a fixed quote.
Do you seal on top of existing sealant?
No. Failed sealant is removed and the faces cleaned back to sound, dry material first, since fresh sealant will not bond reliably to aged material.
Can you clear a mastic snag list before handover?
Yes. We can work through a mastic snag list area by area before handover, cutting out damaged or poor joints and resealing them.
Are you CHAS accredited?
We are CHAS accredited and a Constructionline member, with CSCS-carded applicators. We are also fully insured, with five million pounds of public liability cover.
Can you seal external joints in wet or cold weather?
External sealing goes ahead only with a dry joint inside the product’s temperature range. Wet or cold joints cause adhesion problems, so we wait rather than redo work.
Nearby places to Cosham
Other services in Cosham
Do you need construction mastic in Cosham?
On a live site, contamination is the biggest threat to a new joint. Plaster dust, release agents, protective film residue and damp all stop sealant bonding, so preparation matters as much here as on a reseal.
Common reasons buildings call us in:
- Mastic snags holding up handover
- Existing joints on a refurb that need cutting out and resealing
- Internal caulk splitting as the building dries out
- Inconsistent sealant finishes from plot to plot
When a college such as Portsmouth College (to the south of Cosham) builds or refurbishes, the mastic package usually has to fit around students and staff.
Before you book anyone
- What site paperwork they can supply
- Whether old or failed sealant will be cut out, not overlaid
- Can the work be phased to keep areas open?
- Their pre-qualification and accreditations
For managing agents and facilities managers
When you manage a building on behalf of an owner, you need clear quotes and clear reporting. You get a fixed quote, an agreed scope and a walk round at the end, plus a 12-month guarantee.
Whether you are a managing agent, a property factor or an owner’s representative: send details, get a fixed quote, we seal, guaranteed. We can agree access arrangements and keyholder contacts beforehand.
From enquiry to sign-off
Our CSCS-carded applicators arrive with the sealants, primers and backing rod the job calls for. Joint faces are cleaned back to sound, dry surfaces, the manufacturer’s primer is applied where it’s called for, and the sealant is tooled off neatly. Work in places the size of Cosham is planned as a single visit where we can. Clear photographs and measurements help us bring the right products.
- We walk the site or review drawings to understand the package.
- You receive a fixed quote covering scope, products and sequence.
- Site paperwork is confirmed and our CSCS-carded applicators are inducted.
- Sealing follows the programme as areas are released.
- Problems we find, such as oversized gaps, are raised straight away.
- Final snagging is completed and the 12-month guarantee applies.
Before we start on site
- Tell staff and tenants when we’ll be in
- Point out any areas we must not close
- For older buildings, check the asbestos register before work
Getting a fixed quote
Every job follows the same four steps: send details, get a quote, we seal, guaranteed. To take the first step, give us a call on 01277 525 020 or email the details over.
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Why it’s worth doing now in Cosham
Some packages split mastic across the window fitter, kitchen fitter and plumber. In practice it often means different standards, gaps in responsibility and snags nobody owns. One mastic subcontractor for the lot keeps it simple and a consistent finish. Small buildings around Cosham suffer from failed joints as much as large ones. Catching it early means a reseal rather than repairs.
Larger quantities, tricky access or phasing all shape the price. So do site requirements such as inductions and permits.
Why choose Mastic Doctor in Cosham
- Fully insured, including public liability cover
- 12 months’ guarantee on every job
- Over 20 years of commercial sealing
- Health and safety: CHAS accredited
Read our cost guide and how we’re accredited.