Glasgow · Scotland
Window & door mastic in Knightswood, Glasgow
Mastic around window and door frames, sills and patio doors for householders, landlords and businesses in Knightswood. Fully insured, ARBOMaster approved and guaranteed for a year.
- A bead that does not match the frame
- Cracked sealant at the sill ends
- Gaps left after new windows were fitted
About our window mastic in Knightswood
Some gaps around frames are far deeper than they look. Packing it solid with sealant gives a joint that can’t flex, so we fit backing rod to set the right depth. The sealant then grips the two sides it should. Typical jobs include damp patches on the reveal after heavy rain and cracked internal joints between frame and plaster, on patio & French doors, timber windows & doors and window sills.
Sash and case windows are a feature of older tenements in all four Scottish cities, and plenty still have them. Whether you’re in a tenement flat or a house in Knightswood, the joint between frame and wall is what keeps the weather out.
Whatever the size of the job, it’s backed by our 12-month guarantee in Knightswood and across Glasgow.
- Where
- Knightswood (G13)
- Region
- Glasgow
- Cover
- 12 months on all our work
- Price
- A clear quote up front
- info@mrmastic.co.uk
- Page updated
- 26 October 2026
The process
A visit follows a simple pattern: we look at the joints together, mask and protect the surrounding surfaces, carry out the job and tidy away. It usually takes most of a day for a typical house, less for a few frames. In a city area like Knightswood, parking may be by permit or pay-and-display, so tell us what’s nearby. If you are in a flat, let us know how we get in at the street door.
- Each frame is looked over and we agree which ones need resealing.
- The old mastic is cut out and scraped back to clean surfaces.
- Deep gaps get closed-cell backing rod to set the depth.
- The new sealant goes on in white, brown, anthracite grey, black or clear to suit.
- Every joint is tooled smooth and checked before we leave.
Preparing for the visit
- For business premises, tell us about site rules or sign-in
- Mention if the joints have been sealed before
- Tell us about any water getting in
Ask for a quote
Want a quote for window mastic? Please drop us a line at info@mrmastic.co.uk with a few details. You will know what we plan to do, and what it will cost, before any work begins.
Related advice
Questions from Knightswood
Do you work for landlords with property near Westerton station?
Yes, landlords and agents are among the people we work for. Just email us at info@mrmastic.co.uk with the address and what needs doing, and we will give you a clear quote.
Can you do window mastic in Knightswood?
Yes, Knightswood is within the area we cover. We work across all of Scotland. You can drop us a line at info@mrmastic.co.uk and tell us what needs doing, and we will give you a clear quote.
Do you guarantee window mastic?
Yes, with our one-year guarantee. Keeping drainage clear and checking the joints yearly helps them last.
Are you an approved applicator?
Yes. We are approved under the ARBOMaster scheme, which is run for the Arbo sealant brand.
Where is Mr Mastic based?
Our base is Crawley, with over 20 years’ experience. We work across South East England, London and Scotland.
How long before the joint can be used?
Cure times vary by product and the conditions. We tell you how long to leave it before we go.
Do you have sealant for grey or black windows?
Yes, in most cases. Tell us the frame colour when you get in touch and we’ll match it as closely as we can.
Will new mastic stop draughts?
It will if the frame joint is the problem. We check where the draught is before work begins.
Work for landlords, hotels and businesses
Housing providers, facilities teams and property managers book us too. We can quote a run of properties together.
We regularly work with letting and managing agents. Send the address, what’s needed and the access arrangements and we’ll give you a quote.
What affects the quote in Knightswood
We don’t publish a price list. What we look at:
- The product the joint needs
- Whether old sealant or filler has to be cut out
- How easy the joints are to reach
- The amount of work
Combining jobs into one visit usually makes better use of the time than several visits, so it’s worth mentioning everything you’d like done. You’ll get one clear quote for the whole job.
Helping us quote
When you call or email, these details help:
- Photos by email, if that is easy
- Whether it has been sealed before
- The rough size of the job
- How we’d reach the joints
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 is easy.
Window mastic in Knightswood: local notes
Glasgow’s tenements are largely red and blond sandstone, and sandstone is porous, so any sealant against it has to be one that will not stain or attack it. Under the Tenements (Scotland) Act 2004, shared parts of a tenement, such as the roof and outside walls, are looked after by the owners together, and many buildings use a factor to arrange it. Windows usually belong to the flat, but the title deeds have the final say.
Rented homes near Westerton station change hands often, and cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets. Managing a site like Knightswood Secondary School? Then larger buildings have plenty of frames, and the mastic around each one ages.
Knightswood is about 2 miles south of Bearsden, in Glasgow. Every kind of property in Knightswood can book us for window mastic, old or new, large or small. Every job comes with our 12-month guarantee. Our Glasgow coverage runs to 183 places, and Knightswood is one of them.
Every address in G13 is within our area for window mastic. Window mastic is available to properties on Ryvra Road, Thane Road and Saxon Road. We also cover the places around Knightswood: Anniesland (1 mile south-east), Netherton (1 mile north-east), Temple (1 mile east), Anniesland Cross (1 mile south-east) and Jordanhill (1 mile south). Further out, we also cover Glasgow (4 miles south-east), Woodlands (3 miles south-east), Woodside (3 miles south-east), North Kelvinside (3 miles south-east), Garnethill (3 miles south-east) and Anderston (3 miles south-east).
Landmarks near Knightswood
Typical jobs here are in homes near Scotstoun Primary School, Jordanhill College and Lock 27 pub, among other places. For rail, the closest station is Westerton station, roughly 0.8 miles north of the centre. Nearby you’ll also find Renfrew Castle (1.8 miles south-west) and Renfrew Museum (2.1 miles south-west). Green spaces nearby include Kilmardinny and Castle Hill.
Honest limits
It helps to know what we can’t do too:
- Damp coming through the wall itself rather than the frame joint
- Draughts through the window seals rather than the frame
- A frame that has rotted at the joint
If in doubt, drop us a line at info@mrmastic.co.uk and we’ll say what we think before booking.
Surfaces we seal
- Composite doors
- Patio & French doors
- uPVC windows
- Aluminium frames
- Window sills
- Timber windows & doors
Looking after it afterwards
Joint life depends on how it’s used and looked after. We suggest:
- Make sure the drainage slots aren’t blocked
- Keep solvents and bleach off the sealant
- Keep paint and stain on wooden frames in good order
- Ventilate rooms so frames don’t stay wet inside
Silicone can’t generally be painted, so mention any painting plans before work begins. There are paintable sealants for joints that need it.
Signs to watch for: cracks in the mastic, gaps you can see light through, damp on the reveal or mould around the inside of the frame. Any of these is worth a call.
Signs you need window mastic in Knightswood
Joint shape matters as much as the product. A skim of sealant over a wide gap soon tears, and a gap filled solid cannot flex. That is what backing rod is for.
People generally contact us after spotting something like this:
- Old mastic that has gone black or come away
- Cracked or shrunken mastic around the frame
- Gaps between the frame and the inside reveal
- Rain getting in at the frame or under the sill
For an older house near a landmark such as Knightswood St Margaret's Parish Church, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Questions to ask before you book
- How the surfaces are prepared before sealing
- Which colour the sealant will be
- Whether they’re fully insured
- Whether they seal over old material or remove it
Should I try it myself first?
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.
Sealing over old silicone is the commonest DIY error. New silicone won’t bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.