For example, if we are aiming for a 10mm joint and relying solely on judging by eye, it's a certainty that some will be 8mm-ish and others will be 12mm-ish.

Gapfast - Flag Paving - Video

SuDSFLOW spacers are designed to be equal to or exceed the compressive strength of the nibs on conventional permeable block paving units. They even come in two standard formats, as Tees and as Crosses to best suit the laying pattern being used.On too many jobs, we saw lesser installers simply fill the empty joint leaving the fallen timber spacer in situ, where it would eventually rot away and leave a weakness-inducing void in the jointing material. So the 5m guidance provided for by Buildings Regulations for soakaways (which provides for a single point discharge) need not apply.

Resiblock GapFast tees (Pack of 50) | Resiblock

The 20mm Self-Levelling Slope Corrector with 5mm Spacers attaches to the top of a pedestal to support paving and comes with 5mm spacers. The new paving unit is pushed tight against the GapFast Spacer and an accurate, consistent joint width is instantly created.

It is important to ensure that the first tile is laid correctly as a starting point, as not all floor or wall surfaces are perfectly level. However, although they don't degrade in the same way as timber, the solid plastic prevents the essential jointing material from fully filling the space between paving elements, and so, once again, we have a potentially weakened joint.