Facade and window perimeter sealing
External facade joints and window and door perimeters resealed on commercial buildings, with the product chosen for the frame, the facade and the exposure.
- Water appearing at window heads, reveals or sills
- Perimeter sealant cracked, shrunk or pulled away from the frame
- Cladding joints open to wind-driven rain
Facade and window perimeter sealing: send details for a fixed quote
Send drawings, photos or a joint schedule, or tell us about the site, and we’ll come back with a fixed quote.
What facade and window perimeter sealing covers
On a commercial facade, sealant closes the gaps between frames and the structure, between cladding panels, and at copings and flashings where sealant is the specified fix. Those joints face sun, rain, wind and temperature swings every day, and they age faster on exposed elevations. When perimeter sealant cracks or lets go, water can track into reveals, behind cladding or down inside the wall, and it often appears some distance from where it got in. We reseal window and door perimeters, shopfront frames, cladding panel joints and the perimeter joints where frames meet the surrounding structure. Low-modulus neutral-cure silicone suits many of these joints, because it moves easily and won’t attack frames or stone the way some acetoxy products can. Before quoting, we consider whether the leak really is the sealant, because water at a window can also come from the frame itself or the wall around it.
We work across South East England, Greater London and all of Scotland. Our workmanship carries a 12-month guarantee, we’re CHAS accredited and a Constructionline member, and our applicators hold CSCS cards.
Problems we put right
- Water appearing at window heads, reveals or sills
- Perimeter sealant cracked, shrunk or pulled away from the frame
- Cladding joints open to wind-driven rain
- Sealant chalking and hardening on sunny elevations
- Earlier repairs smeared over the old sealant
- Staining on stone or brick around old joints
Joints and areas we seal
- Window and door perimeters
- Cladding panel joints
- Perimeter joints where frames meet the structure
- Coping and flashing joints
- Shopfront frames
- Stone and brick facade joints
At a glance
- Fixed quote, scope in writing
- CSCS-carded applicators
- CHAS accredited · Constructionline member
- £5m public liability insurance
- 12-month guarantee
How it works
- Send photos of the elevations and any leak locations, with notes on how each joint can be reached.
- We study the joints and frames to judge whether the sealant is really letting the water in.
- You receive a fixed quote covering the elevations, joint lengths and product.
- Old sealant comes out, and frame and facade surfaces are cleaned back and primed where specified.
- Depth is controlled with backing rod, then new sealant goes in and is tooled to a weathertight finish.
- We confirm what was sealed, and the work carries our 12-month guarantee.
Is it really the sealant?
Water at a window doesn’t always come through the perimeter joint. Failed gaskets, blocked drainage slots in the frame, cracked sills or defects in the wall can all produce the same stain. We look for the likely route before recommending a reseal, and if the sealant is not to blame, you’ll hear that from us rather than a quote for work that won’t stop the leak.
Weather and external work
External sealant needs a dry joint, with surface and air temperatures inside the product’s range. Cold, damp or frosty mornings can hold work up, and condensation on glass and metal frames is common in winter. Rainfall varies too: the South East sees comparatively little, while western Scotland gets noticeably more than the east coast, so we plan external dates with that in mind and keep you informed if conditions move a start.
Curtain walling and cladding
On buildings with curtain walling, our work is limited to the perimeter joints where the frames meet the structure. We don’t install or alter curtain walling, structural glazing or cladding systems. On cladding panels, we reseal the joints where sealant is the specified seal, following the manufacturer’s recommendations for the product. If a leak traces back to the system itself rather than a sealed joint, we’ll tell you so the right specialist can be involved.
Choosing the product
Facade joints meet glass, aluminium, powder-coated steel, uPVC, stone, brick and render, often within one run. The sealant has to bond to both sides and suit the expected movement, so low-modulus neutral-cure silicone is common, with hybrid polymer or polysulphide used where the specification or substrate calls for them. Acetoxy silicone is avoided on most building joints because it can attack some metals and stone. Primers go on where the manufacturer specifies them for that substrate.
Why it’s worth doing now
The perimeter joint around a window or panel is the line between the weather and the building. When it shrinks, cracks or peels away, rain is driven into the gap, and stains, damp patches and damaged linings follow inside. Resealing early is far simpler than chasing leaks later.
What affects the quote
We don’t publish set prices, because no two buildings are the same. Send details and we’ll give you a fixed quote before we start. The main things that affect it are:
- How many metres of joint there are, and how many areas, elevations or sites
- How much failed sealant has to come out, and how hard it is
- Joint size, depth and whether backing rod or primer is needed
- Access: height, scaffold or MEWP access arranged by others, occupied areas
- The product the joint needs (and colour, where it matters)
- Programme, phasing and site requirements such as permits and inductions
What a good quote includes
- All failed sealant removed, never sealed over
- The product named for each joint type
- What the 12-month guarantee covers
- When each area can be used again
- Who is doing the work, their CSCS cards and the insurance in place
- What site paperwork and records are included
Aftercare
Inspect perimeter joints on the most exposed elevations each year, especially faces that take the sun and the prevailing weather. Keep drainage paths and sills clear, and report water inside straight away so the source can be traced before linings are damaged.
Trusted. Accredited. Insured.
Facade and window perimeter sealing: common questions
Can resealing stop water getting in around windows?
If the water is entering through the perimeter joint, yes. If it is coming through the frame or the wall, a reseal won’t fix it, and we’ll tell you.
Which sealant do you use on facades?
Often a low-modulus neutral-cure silicone, though the specification, the substrates and the joint movement decide. Some joints suit a hybrid or polysulphide sealant.
Can you match the frame colour?
Sealants come in a wide range of standard colours. We’ll confirm the colours available for the specified product.
Do you install curtain walling?
No. We reseal perimeter joints where frames meet the structure, but we don’t install curtain walling or structural glazing.
Can external sealing go ahead in winter?
Yes, when conditions allow. Damp, frost and condensation can delay external sealing on some mornings.
Do you give a fixed price before you start?
Yes. Send photos, drawings or a joint schedule, or we can visit, and we’ll give you a fixed quote with the scope in writing before any work starts.
Are you accredited and insured?
Yes. We’re CHAS accredited and a Constructionline member, our applicators hold CSCS cards, and we carry £5m public liability insurance.
Page updated 3 November 2026
Near you
Find facade and window perimeter sealing in your town:
- London
- Glasgow
- Edinburgh
- Aberdeen
- Dundee
- Southampton
- Portsmouth
- Brighton
- Reading
- Oxford
- Guildford
- Chelmsford
- Maidstone
- Milton Keynes
- Watford
- Basildon
Advice
- Leaks Around Windows on Commercial Buildings
- Sealant and Curtain Walling: General Guidance
- Weather and Sealant: When Work Can Go Ahead
- Sealing Precast Concrete and Cladding Joints
- Silicone, Polyurethane or MS Polymer Sealant?