A paved surface is not a solid slab. It is a collection of separate units held in place by what surrounds them, and everything that goes wrong later comes down to that arrangement loosening. Blocks creep, joints open, weeds arrive in the gaps, and a surface that was tight becomes one that shifts underfoot.
Miller Landscaping lays paving across Lockerbie for paths, seating areas, entrances and the transitions between parts of an outdoor space. This is what keeps a surface tight, and what lets it come apart.
The joint is a structural component
It is tempting to think of the gaps between units as the leftover space. In block paving they are the opposite: the filled joint is what transfers load from one block to its neighbours, and it is why a properly laid surface behaves as a whole rather than as a thousand loose pieces.
That is why the joint has to be full. A surface where the sand has washed or blown out of the top of the joints has lost part of its structure, and it will begin to rock and spread under traffic long before anything visible breaks.
It is also why joint width is specified rather than improvised. Joints too wide never lock properly; joints too tight leave nowhere for the filling material to go and cause units to chip against each other as they move.
- The filled joint transfers load between units; it is not a gap.
- Joints emptied by weather or jet-washing lose that structure.
- Joint width is part of the specification, not an accident of laying.
- A rocking block usually means an empty joint, not a broken block.
Jointing methods and what each asks of you
Kiln-dried sand is the traditional approach for block paving: brushed into the joints and vibrated in, topped up as it settles. It is cheap and it works, but it can be washed out by heavy rain or removed wholesale by an over-enthusiastic pressure washer, and it is where most weed seed germinates.
Resin and polymeric jointing compounds set to resist washout and to suppress weed growth. They cost more and they are less forgiving of poor preparation, because they need the joints clean, the right depth and the right weather when they go in. Done properly they are excellent; done in the wrong conditions they fail visibly.
Mortar jointing suits some slab paving on a rigid bed but is not appropriate for flexible block construction, where the whole point is that the surface can flex slightly without cracking.
None of these is universally right. The correct choice follows from the paving type, the construction beneath it, the traffic it will take and how much maintenance is realistic.
Edges again, because this is where movement starts
Paving almost never begins to fail in the middle. It begins at a free edge, where there is nothing resisting sideways movement, and works inward as each row loses its restraint in turn.
That is why the edge detail is worth more attention than the field. A properly bedded and haunched edging holds the perimeter, and it needs to be continuous. A single gap where an edging was omitted around a gully or against a step is enough to start the process.
The other common weak point is where paving meets something soft: a lawn, a border, a gravel strip. Those junctions need a physical restraint even where the finished appearance is meant to look seamless, because grass and soil offer no resistance at all.
Where paving forms the transition between different parts of a space, those junctions are exactly where the restraint detail matters most and where it is most often skipped.
- Failure starts at free edges and moves inward.
- Edge restraint must be continuous, including around gullies and steps.
- Junctions with lawn, border or gravel always need a physical restraint.
- Check the perimeter first when a surface starts to move.
Maintenance that helps, and maintenance that harms
The most common way people damage their own paving is with a pressure washer. Held too close, or used with too fine a jet, it strips the jointing material out and erodes the surface of some materials. The paving looks immaculate that afternoon and is structurally worse than it was that morning.
If a surface is washed, the joints should be refilled afterwards. That single habit prevents most of the slow loosening that follows a spring clean.
Weeds in joints are usually growing in material that has blown in on top rather than rising from below, which means keeping joints full and brushing debris off is more effective than treating repeatedly.
Beyond that, paving asks very little. Keep the joints topped up, keep water draining where it should, and deal with any block that starts to rock rather than waiting for its neighbours to follow. Miller Landscaping lays paving in a range of colours, combinations and designs, and any of them will last far longer with those three habits than without them.
Related pages
Questions customers ask
Why is my block paving becoming uneven?
Usually because the joints have emptied or the edge restraint has failed, so the blocks are no longer locked together. Check the perimeter and the joint fill before assuming the problem is underneath, though a sunken area under a wheel track does point at the sub-base.
Is pressure washing bad for paving?
It can be. It strips jointing material out of the joints and can erode softer surfaces. If you do wash a surface, keep the nozzle back, use a fan rather than a pencil jet, and refill the joints afterwards.
Is resin jointing better than kiln-dried sand?
It resists washout and suppresses weeds better, but it is less forgiving: it needs clean joints of the right depth and the right weather to install. Sand is cheaper and easily topped up. The right answer depends on the paving type and the maintenance you will actually do.
Keep the joints full, keep the edges restrained, and be careful with a pressure washer. Almost every paving surface that has come loose lost one of those three first.
Miller Landscaping lays paving across Lockerbie for paths, seating areas and entrances. The contact page is the place to describe the area you have in mind.
