Movement joint sealing in North London & the Home Counties
Movement joint sealing covers expansion and settlement joints, sealed with low-modulus sealant and correct backer rod, specified to the movement expected. Domestic and commercial work, including joints run to a specification.
What the job includes
Before
After- Full removal of existing or failed joint material
- Correct backer rod sized and fitted to set joint depth
- Low-modulus sealant specified to the movement expected
- Domestic and commercial joints, indoor and exterior
- Joint geometry checked to avoid three-sided adhesion
- Work area left clean and joint ready for use
How the work runs
Scope agreed
We assess the joint width and expected movement, and price before starting.
Strip out
Old or failed joint material removed back to sound substrate.
Backer rod fitted
Correct-diameter backer rod packed in to set sealant depth and stop three-sided adhesion.
Apply & finish
Low-modulus sealant applied and tooled to a clean, consistent profile.
Work in this trade
Movement joint sealing FAQs
What's a low-modulus sealant, and why does it matter?
Low-modulus sealant stretches and compresses without tearing, which is essential in a joint designed to move — a standard sealant will crack out under the same movement.
What is backer rod, and do I need it?
Backer rod is a foam rope packed into the joint before sealing. It sets the correct sealant depth and stops three-sided adhesion, which is what causes movement joints to fail early.
How wide can a movement joint be and still be sealed?
Most joints from a few millimetres up to around 50mm can be sealed correctly with the right backer rod and sealant profile. Wider joints may need a specified movement joint system.
Is this different from ordinary silicone sealing?
Yes — a movement joint is designed to expand and contract, so it needs a specified sealant and correct joint geometry, not just a bead of standard silicone.
Get a price for your joints
Send a couple of photos and rough measurements and we'll quote from those. Or call 07413 240639.