Failing sealants and gaskets: the silent façade problem.

The short version: the flexible sealants in the joints and the rubber gaskets around the glazing are consumable — they have a service life, and when they reach it they let water in and let glazing move. They're cheap to renew and expensive to ignore, because what they cause is leaks and, eventually, structural damage.

What they actually do

A façade isn't one solid skin — it's panels, frames and glass with gaps between them that have to flex as the building moves and the temperature changes. Flexible sealant in those joints, and rubber (usually EPDM) gaskets around the glass, are what keep weather out while allowing that movement. They're doing real work every day, and like anything that flexes in the sun, they wear out.

Why they fail — and why Melbourne is hard on them

Most façade sealants and gaskets have a practical life of around 10 to 15 years. UV breaks down the polymer, repeated thermal movement fatigues it, and any shortcuts in the original installation (poor prep, wrong product, no primer) bring the failure forward. Melbourne adds UV, big daily temperature swings and wind-driven rain pushing at every joint — so on exposed south and west elevations, sealants often reach the lower end of that range. And because so many local towers went up in the same boom-era window, a lot of them hit end-of-life sealant at the same time.

The signs

• Sealant that's gone hard and lost its stretch — press it and it doesn't give.
• Crazing or chalking on the surface, or a colour that's faded and powdery.
• Cracks down the side of a joint where the sealant has pulled away from the substrate (adhesive failure) or split down the middle (cohesive failure).
• Visible gaps — daylight through a joint, or somewhere you could fit a blade.
• Shrunken or hardened glazing gaskets, sometimes with the glass starting to rattle or move.
• And very often, the first thing anyone notices: an unexplained internal leak.

What it leads to if left

Failed sealant is rarely the end of the story — it's the start. Water gets in and shows up as ingress somewhere unexpected; over time that same water drives concrete spalling and damages internal finishes. Loose glazing becomes a safety question of its own. Renewing sealant on a cycle is one of the cheapest things you can do to a façade; the damage from not doing it is some of the most expensive.

How it's rectified — by rope access

Re-sealing and re-gasketing is ideal rope-access work. We cut out the old sealant, prepare and prime the joint properly, and install new sealant — or replace perished glazing gaskets — across the whole elevation on rope, without erecting scaffold. It folds neatly into façade repairs and glazing works, and it's exactly the kind of thing a maintenance program stays ahead of.