What movement can the joint take?

Horizontal, vertical and shear movement at the same time. The membrane and the cover are sized to the movement of the joint.

Does the joint need a kerb or a gutter underneath?

No. The membrane is bonded flat across the gap, so water flows across the roof.

How are lengths of membrane joined?

By machine vulcanising, not by hand welding.

What about construction joints?

Below ground and in tanks and pools, a CENTRESEAL 250 PVC waterstop is cast into the joint with the concrete.

All systems, by building zone

Expansion and Construction Joint Waterproofing.

Car park decks, podiums, bridges and long buildings. The joint is designed to move; the treatment has to move with it for thirty years and still keep the water out. This page sets out the four parts of the joint and the order of work.

The build-up.

Four parts, from the concrete to the cover.

As numbered on the drawing

Prepared concreteHydro-scarified so the grout keys in.
CHEMGROUT 215Non-shrink grout with aggregate, reinstating the joint edges.
FLEXJOINT EPBonded expansion joint waterproofing membrane across the gap. An EPDM synthetic rubber sheet, reinforced at both edges and set in epoxy adhesive.
Mechanical joint coverAluminium or stainless cover system, sized to the movement.

The expansion joint build-up drawn exploded: two slabs with a gap, scarified recesses, grout nosings, primer, deck coating, the looped joint membrane and the cover plate

How the job runs.

The concrete is preparedThe slab on each side of the joint is hydro-scarified, so the grout keys in.
The joint edges are rebuiltWith CHEMGROUT 215 non-shrink grout and aggregate.
FLEXJOINT EP is bonded across the gapThe membrane is set in epoxy adhesive on both sides. Its reinforced edges hold the bond and its centre is left free to stretch.
The joint, bridgedFLEXJOINT EP laid over the movement joint
Lengths are joined by machineWhere two lengths meet they are vulcanised by machine, not welded by hand.
The cover goes onA mechanical joint cover in aluminium or stainless steel, sized to the movement.

Movement, edges and lengths.

Movement
The membrane takes horizontal, vertical and shear movement together.
Kerbs and gutters
None are needed under the joint. The membrane lies flat, so water flows across the roof.
Adjoining waterproofing
FLEXJOINT EP is compatible with the waterproofing system on either side of the joint.
Lengths and corners
Rolls are cut to the site measurements, and special pieces are prefabricated.
Construction joints
Below ground and in water-retaining structures, a CENTRESEAL 250 PVC waterstop is cast into the joint. See basements and retaining walls.

Materials.

FLEXJOINT EP
EPDM synthetic rubber joint membrane, reinforced with polyester fleece at both edges and set in epoxy adhesive.
CHEMGROUT 215
Cementitious non-shrink grout.
Joint cover
Aluminium or stainless steel cover system, sized to the movement.

FLEXJOINT EP and CHEMGROUT 215 are made by CHEMIND. Where a project specifies another manufacturer's system, we apply that instead.

Questions we are asked.

What movement can the joint take?: Horizontal, vertical and shear movement at the same time. The membrane and the cover are sized to the movement of the joint.
Does the joint need a kerb or a gutter underneath?: No. The membrane is bonded flat across the gap, so water flows across the roof.
How are lengths of membrane joined?: By machine vulcanising, not by hand welding.
What about construction joints?: Below ground and in tanks and pools, a CENTRESEAL 250 PVC waterstop is cast into the joint with the concrete.

Talk to us about joints.

Phone and WhatsApp016-332 7534

Emailinfo@hydrocon.com.my