Joint Sealing

It is at the joints where a building is weakest to leakage because this is where different building elements, materials and trades meet.

Joint Sealing

A joint is where two components meet and may occur within an element of construction or at part of an interface between two elements to control cracking and to provide relief for concrete expansion and contraction caused by temperature and moisture changes. Joints allow for needed movement of the materials but must remain water, air, heat, cold and vapor tight. Joint seals correctly specified and professionally applied will manage to keep the structure sustainably tight during its entire lifespan. You can count on BuildIn as a certified applicator and as an experienced contractor to handle such a critical
activity of your project. To know more about our services, checkout our projects or get in touch with our experts.

Typical Types of Joints in Structures

  • Construction joint

Construction joints are designed between concrete placements intentionally created to facilitate construction, or as a structural measure to transfer load, for example. The reinforcement in construction joints is therefore continuous through the joint.

  • Connection joint

Connection joints are a means of joining individual members of concrete sections through its full thickness without a defined joint gap to form a complete assembly. The reinforcement in connection joints is discontinuous. When the concrete section contracts, joint movement (joint opening) is possible. When it expands, pressure transmission is possible.

  • Movement joint (Expansion joint)

Movement or expansion joints split components through their full thickness with a joint gap of defined width to allow and accommodate the expansion of adjacent elements. The reinforcement in movement joints is discontinuous. Movement joints allow differential movement primarily due to thermal movement, but also many other possible influences such as load or settlement in one or more directions of the areas, sections or structures separated by the joint. An expansion joint sealing system must be designed and installed to effectively compress or expand to accommodate this movement, whilst maintaining a watertight seal.

  • Control Joint (Controlled Crack-Induced, Dummy or Contraction Joint)

Control joints are intended to control cracks by engineered concrete cross-section weakening and formation of a controlled point of cracking through the concrete. This relieves stresses due to temperature and shrinkage, which thereby prevents uncontrolled cracking in the wall. Cracking takes place in the designed and crack-induced position instead.

Joint Sealing Solutions

1. Construction Foams

Construction foams are mainly polyurethane (PU) resin-based foams, which cure in contact with moisture when applied. They can be used as a gap-filling, adhesive
sealant to fix, fill and insulate against noise, cold, and drafts because they have good insulation properties and are effective at dampening sound. They are also used to bond insulation panels and insulating system components on top of each other due to their excellent adhesive properties and fast curing ability.

2. Building Envelope Systems

Sustainable construction begins with an efficient building envelope as the energy lost through a building's walls, roofs and windows is the largest single waste of energy. As the single largest building element, the building envelope (shell) separates the interior of the building from the external environment and includes the roof, walls, windows, glazing, floors and all the joints in between. A high-performance envelope must meet the project’s requirements for acoustic, thermal, structural, visual, air-quality, fire-resistant, watertight, temperature-control and aesthetic needs.

3. Firestop Systems

Fire protection is an increasingly important part of today’s building industry largely due to urbanization as it increases the risk is for a life-threatening fire to spread quickly. Buildings and structures need protection against this imminent threat, therefore firestops are installed to prevent the spread of flames, deadly gases and toxic smoke through openings created during building upgrades and the installation of electrical, communications, plumbing, and ventilation systems, as well as grease ducts. That's why it is important to include passive fire protection – firestop systems – in any building design, right from the start of a project.

4. Civil Engineering Joints

Civil engineering generally deals with the construction, maintenance and repair of all types of utility and infrastructure projects. All these projects contain joints and connections which need to be securely sealed and protected.

5. Joint Waterproofing

Due to the nature of concrete and reinforced concrete, structures are divided into sections by forming joints that are designed to accommodate movement, namely three types – construction joints, movement joints and connection joints. The key function of joint sealing is to minimize water ingress and create a secure waterproofing barrier. It is important to consider when waterproofing joints in concrete structures that the seal used can accommodate the type of joint and the anticipated joint movement due to static reasons or temperature changes. The sealants must be permanently elastic, form stable and offer UV-resistance to protect against damage that may occur from any future movements. Joint sealing solutions are recommended for use in all kinds of construction and joints for waterproofing.