Vexcolt FAQ Expansion joint systems

Ti-Lock Series Movement Control Joints

React Architectural
Expansion Joints
- 100 Series
- 300 Series
- 400 Series
- 500 Series
- 600 Series
- 700 Series
- 800 Series

React Exterior Seals and Heavy Duty Expansion Joints
Seals and
Membranes
1000 Series

Heavy Duty Joints
1100/1120 /1200/1300

Reactofire
Fire Barriers

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FAQ Expansion joint systems

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What is an Expansion Joint?
An expansion joint is an opening within a structure, at a predetermined location, to absorb movement of the structure.
Movement may be defined as follows:

1. Thermal / Drying - caused by temperature and drying shrinkage changes within the structure. Thermal/drying movement is horizontal.
2. Settlement - caused by the dead and super dead load of the structure on the supporting substrate. Settlement movement is vertical.
3. Seismic - caused by earthquake activity beneath the structure. Seismic movement may be horizontal, vertical or shear,
or a combination of all three.
4. Windload induced - caused by high winds forcing the structure to sway. Windload induced movement is normally horizontal or shear.

What are Movement Ratings?
A movement rating is an attempt to categorize the anticipated range of horizontal change in a joint opening. For example, a 100mm nominal joint which is expected to have a range of horizontal movement of plus 50mm or minus 50mm, could be denoted as (100mm+/- 50%) Alternatively the actual physical movements may be defined - 100mm ±50mm. Joints designed for thermal movement will typically have a movement rating in the +/- 10% to +/- 20% range. Joints designed for seismic movement will typically have a movement rating of +/- 50% to +/- 100%. Joints designed for windload movement will normally be rated as seismic.

What is Nominal Joint Width?
Nominal joint width is the design width of the structural gap at median temperature. In some cases, the joint opening is different at time of installation of an expansion joint system (EJS). This may simply be due to thermal/drying shrinkage conditions. In this event, the installation of an expansion joint is not normally impeded.

What is an Expansion Joint System (EJS)?
This is simply a transition across an expansion joint opening. In other words it is a cover, or an insert. Covers may be simple cover plates and inserts may be simple compression seals. Many systems are engineered to fulfill a variety of additional functions and it is these functions together with the way the systems have been designed to perform them, that has given rise to a broad range of systems. Some of these functions include:

1. Fit a predetermined opening size.
2. Absorb building movement, thermal or seismic.
3. Be compatible with various surface finishes.
4. Support a given load.

How do I select an Expansion Joint System (EJS)?
As with most architectural products, the EJS should be selected on the basis of Function and Form. First, determine the function. For example, will the system be installed on the floor, wall, ceiling or roof? If it is a floor system, what loading will it be subjected to? Is it to be an interior or an exterior system? Secondly, determine the form, or appearance of the desired product. Should the system match a hard tile floor? Should it be concealed, or is an exposed cover plate acceptable? The expansion joint systems described in this brochure will provide the most comprehensive and advanced range available in the world today.

Is Loading important?
Yes. For any floor system it is important to know how much load the EJS will be subjected to. Any load in excess of the system design load may cause the system to fail. Failure in an EJS may result in danger to pedestrians and damage to vehicles and property. The joint edges may break down and the abutting finishes may be destroyed, creating the need for an expensive and sometimes difficult repair process. In this brochure we have provided load ratings in kN (Kilonewtons) to assist you in your selection process. A description of the derivation of our load engineering is also provided.

Is there any Standard Test Method Applicable to EJS?
All systems comply with the requirements of ASTM-E1399-97 Standard Test Method for Cyclic Movement and Measuring the Minimum and Maximum Joint Widths of Expansion Joint Systems. For information on the scope of this Standard, please contact Vexcolt.

Where are Fire Barriers used and why?

1. In all floor and wall joints that occur in fire rated locations ad potentially compromise compartment zones.
The Fire barrier is often located beneath the EJS.
2. To prevent fire and smoke from penetrating an expansion joint opening for the specified rating period, i.e. 2 hours.
3. In some cases, to prevent temperature on the cold side of an expansion joint opening from rising above a predetermined rate for the specified rating period, i.e. 2 hours. The "cold side" of an expansion joint opening refers to the area within a structure adjacent to, or opposite the area where a fire or smoke source is located.

What types of Fire Barrier are used with Expansion Joint System (EJS)?
There are 2 main types of fire barriers used in expansion joint openings. They are:

a.) Compressible intumescent block systems.
b.) Blanket systems.

What Fire Rating Standards should EJS conform to?
There are several approved testing authorities. Some of the most widely accepted are:
1. BS-476 Parts 20 and 22: 1987 - Fire Tests on Building Materials and Structures.
2. UL-2079 - Standard for Tests for Fire Resistance of Building Joint Systems.
In addition, joints employing rubber seals in below ground applications should incorporate *Vamac seals rather than the standard units normally supplied. *Vamac joints have been specifically designed for projects where a high degree of fire resistance and low toxic smoke emission is required. Such installations include underground rail terminals, basement levels of air terminals, hospitals and other areas where personnel (or passengers) work (or transit) below ground level.
Vexcolt's *Vamac synthetic rubber extrusions have been tested and approved to the latest London Underground Limited Engineering Standard E1042:A4 September 2000' Engineering Standard for the fire safety performance of materials used underground'.