Patios & paving · Practical advice
Why do patio joints crack and fail?
Patio joints can deteriorate when the paving moves or the jointing is unsuitable for the conditions. Learn what to consider when checking cracks and failed joints.
Look at the pattern of the failed joints
Jointing can crack, crumble, wash out or separate from the sides of a slab. Start by noting which of these has happened. Failure around one moving unit may have a different cause from shallow joint material breaking down across the entire patio.
Record when the jointing was installed, which product was used if known and whether cleaning preceded the damage. Photographs taken before removing anything can help an installer distinguish a product issue from movement or an unsuitable detail.
Check the paving beneath the symptom
A joint sits between surfaces that must be properly supported. If neighbouring slabs rock or settle, renewed rigid jointing may fail again. Water collecting in the area can point to another issue that needs attention before a cosmetic repair.
Inspect adjacent edges and transitions too. A joint against a building or across a movement detail may need a different treatment from ordinary paving joints. Filling every gap with the same product is not necessarily the correct approach.
Match the material to the installation
Jointing systems differ in required width, depth, preparation, moisture conditions and curing. Some rely on a particular drainage arrangement beneath the paving. The product instructions matter more than whether the material is described simply as grout, mortar or compound.
Ask what failed material will be removed, how the joint will be prepared and how nearby paving will be protected from residue. A thin skim across old material may not provide the depth or contact required for a durable repair.
Repair in the right order
Resolve loose paving, unsuitable levels or drainage defects first. Then prepare and refill the joints with a compatible system under appropriate conditions. Agree the colour and expected appearance, particularly where only one area is being repaired.
Keep traffic and cleaning within the curing guidance. At handover, record the product used and its care requirements. A sound repair should have a clear explanation of why the previous jointing failed and which part of the new work addresses that cause.
Common questions
Can I put new jointing over the old joints?
Only if the specified repair system permits that preparation. Many repairs require failed material to be removed to a suitable depth first.
Does all joint cracking mean the patio is sinking?
No. Material selection, preparation and curing can also contribute. Check for actual slab movement before deciding on the repair.
Discuss your project
Tell us what you would like to change and share photographs of the area. We can discuss the next steps for your property.