Renfrewshire · Scotland
Sand mastic for sash & case windows in Houston, Renfrewshire
Sand mastic for Houston, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Mastic round period door frames that has failed
- Wind and rain getting in round a sash window
- Open joints round the window box
Should I try it myself first?
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.
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
How we handle sand mastic in Houston
Burnt sand mastic is a traditional material that sits naturally against stone and brick. It’s a good fit for period properties, where modern sealant can look out of place. We work on tenement windows, sash and case windows and timber door frames, and the jobs we see most are mastic dropping out of the joint and draughts and rain around sash boxes.
Older stone-built homes in Scotland often have sash and case or timber windows set in stone. Those suit a traditional sand mastic or a neutral-cure sealant, not an acetoxy silicone that can attack some stone.
Our work is backed for twelve months.
- Where
- Houston (PA6)
- Wider area
- Renfrewshire
- Cover
- One year on every job
- Price
- Quoted before any work starts
- info@mrmastic.co.uk
- Page updated
- 26 October 2026
How it works
On the day, we start by going over the job with you, so there are no surprises. We protect the surfaces around the joints before any work starts. Most jobs take a few hours per window, depending on the condition of the joints. Somewhere like Houston may be a longer drive, and the journey is planned ahead. Tell us about tracks, gates, a ferry crossing or anything unusual about getting there.
- We check each window surround and the condition of the joint.
- We rake out the old mastic and clean the joint.
- We fill deep gaps so the new mastic isn’t too thick.
- We point the joint with sand mastic by hand.
- The finish is dressed neatly.
How to prepare
- Tell us about any previous sealing or DIY attempts
- Mention any tricky access
- Where the joints are inside, avoid wetting them before we arrive
How to get a quote
To get a quote, send an email to info@mrmastic.co.uk and tell us where the job is and what the problem looks like. You’ll have a clear quote before any work starts.
Advice
Why act early in Houston
If you’re redecorating, renew the mastic first. Painting over failed mastic does not seal it, and the new mastic is traditionally left unpainted. In a place like Houston, small leaks are easy to put off, but water behind a failed seal does the most damage when nobody’s watching.
What it costs depends on the amount of work, how much old material has to come out and how easy the joints are to reach. You’ll have a clear quote before any work starts.
Why book with us
- More than 20 years in sealant work
- 180+ five-star Google reviews
- Arbo and Everbuild products
- Experience in homes, commercial sites and hotels
Work for landlords, hotels and businesses
Landlords and agents in Houston can book us as well as homeowners. Resealing between tenancies keeps a property looking cared for.
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements.
Surface by surface
Stone surrounds
Stone openings are rarely perfectly straight, so the gap is not the same all the way round. We shape it by hand to follow the stone.
Period and listed homes
Many older homes were built with sand mastic round the windows. If your home is listed, ask your local planning authority about consent.
Also near Houston
Also in Houston
What we’re called out for in Houston
Age is the main cause. Even well-laid mastic needs renewing in time and how long it lasts depends on the weather it faces.
People generally contact us when they notice one of these:
- Mastic dropping out of the joint
- Mastic worn away on windows facing the weather
- Mastic that needs renewing before redecorating
- Gaps between timber frames and stone or brick
Schools such as Gryffe High School are buildings too, and larger buildings have plenty of frames, and the mastic around each one ages.
Comparing quotes
- Whether VAT is included
- What the cure time is
- Who turns up on the day
- What happens if they find a problem under the old sealant
FAQs for Houston
Can you help a landlord with a rental near Johnstone station?
Yes, landlords and agents are among the people we work for. You can drop us a line at info@mrmastic.co.uk with the details for a clear quote.
Is Houston within the area you cover?
Yes, smaller places are covered as well as towns. We work across all of Scotland. Let us know about access, parking and anything unusual about getting there when you book.
Can I choose the sealant colour?
In most cases you can choose. We will explain which colours are available.
Will you leave a mess?
Tidy work is part of the job. We protect what’s around the joints.
How long does sand mastic take to harden?
It skins over fairly quickly but takes longer to harden fully. We will explain what to expect before we leave.
What exactly is sand mastic?
It’s sand mixed with a linseed-oil-based binder, used between timber frames and stone or brick.
Do the sealants smell?
Some sealants have a smell while they cure, but it fades. Opening a window helps.
Do you guarantee sand mastic work?
Every job comes with our 12-month guarantee, and we’re fully insured.
Houston homes and the weather
Private landlords in Scotland must meet the Repairing Standard, which includes keeping a home wind and watertight, and sound outside sealant is part of that. Many older homes in Scotland have sash and case windows, and the joint between the box frame and the stone or render is traditionally pointed with sand mastic.
Rented homes near Johnstone station change hands often, and cracked sand mastic around sash windows lets in the draughts tenants complain about. Homes close to St Fillan's R.C. Church and School include some older properties, and replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint.
Houston is about 3 miles north-west of Johnstone, in Renfrewshire. Jobs in Houston get the same care as everywhere else we work: old sealant removed completely, careful preparation and a 12-month guarantee. Houston is one of 21 towns and villages in Renfrewshire we cover. There’s also a page for Glasgow, roughly 11 miles from Houston.
All of PA6 is within our area for sand mastic. Whether your property is on Main Street, St Fillans Drive and South Street or a nearby road, we can help. Close by, we work in Crosslee (1 mile south-east), Craigends (1 mile south-east), Bridge of Weir (1 mile south-west), Brookfield (2 miles south-east) and Ranfurly (2 miles south-west). We also work in nearby towns such as Paisley (5 miles south-east), Renfrew (6 miles east), Johnstone (3 miles south-east), Erskine (4 miles north-east), Bishopton (3 miles north-east) and Glenburn (5 miles south-east).
What’s near Houston
Locally, jobs take us to homes and businesses close to Linwood High School and Fox and Hounds Inn, among other places. Houston’s nearest station is Johnstone station, roughly 2.9 miles south-east of the centre. Nearby you will also find Ranfurly Castle (1.7 miles south-west) and Merchiston Hospital (1.9 miles south-east). For a walk, there’s Whitemoss Dam and Walls Hill.
Keeping the joints in good condition
So the new joints stay in good condition:
- Keep modern sealant off the mastic
- Keep sills and gutters clear so water drains away
- Get any rot dealt with first
- Go gently near the mastic when preparing windows
Leave the new mastic alone while it firms up. It skins over quickly but needs longer to fully harden.
Sound mastic protects the frame. Once it fails, water can sit against the timber and timber that stays wet can rot.