Expansion & Contraction Joints

Expansion & Contraction Joints

As Structures from roads and buildings to bridges and tunnels are living moving structures that are under constant stress such as thermal expansion and contraction caused by temperature change, sway caused by wind loads, seismic events, static load deflection, live load deflection, settlement of a new building. Expansion joints are used as a structure separation such as in walls, that are designed to relieve these stresses on building materials ensuring the integrity of the building/structure.


Types of loads on structure

Because the joints bisect the entire structure, it marks a gap through all building assemblies–walls; decks; plazas or split-slab concourses; foundation floors and walls; roofs, planters, and green roofs; fire-rated demising walls and floors; interior floors; etc.  This gap must be filled to restore the waterproofing, fireproofing, soundproofing, air barrier, roof membrane, trafficable surface and other functions of the building elements it bisects.

For example, when a structures temperature drops in winter, the materials such brick, mortar, steel, concrete etc. start to contract, this causes the joints to open up and ‘’expand’’, therefore stretching the joint system of this gap. Alternatively, when the structure heats up, these materials will expand, causing the joint gap to close up, compressing the joint system installed.


Examples of joint movement

This is why the products we use are of the highest quality, ranging from Everbuild silicone 825 for structures such as low and medium rise buildings with brickwork, windows, floor joints etc. With a movement accommodation of +/- of 35% to civil engineering structures such as bridges, airport runways, high rise buildings we have products such as Forsroc Thioflex 600 and other products which has a movement accommodation of +/- 50% and a 0.45MPa bonding strength.

Expansion and Construction Joints include:

  • Expansion joints – between new and old brickwork, concrete slabs, wood, Upvc, plastic, asphalt.
  • Remedial works – between new and old brickwork, concrete slabs, wood, Upvc, plastic, asphalt.
  • Floor joints – perimeter sealing.
  • Roadways.
  • Roofing.
  • Lead work joints between lead and masonry with high-temperature changes and movement.

What we offer

With an extensive range of sealants available, it is crucial that an experienced and knowledgeable applicator undertakes the work to guarantee its complete efficiency for your expansion & contraction joints. You can rely on Construction Sealants to ensure that the most effective sealants are selected for the structures joint, and then applied professionally. We will thoroughly examine your building to determine all the critical areas, ensuring that the best measures are installed that ensures the function of the buildings elements is kept intact. Furthermore, we will always monitor the performance of the sealants being used, allowing us to provide constant quality control and helping to establish what products are best suited to particular structures. With all our team with an NVQ level 2 qualification in mastic application and the companies many accreditations to ensure a professional and high-quality service is provided.

CSL Applicators

Our skilled workforce understands the importance of selecting the correct sealant that is best suited to the specifications of your building. Our professionals ensure upon application that all surfaces are clean and dust free, all loose or flaking surface coatings, and old sealant and mastic joints, are removed before application.

We pride ourselves on being at the forefront of this specialist field, ensuring that the most suitable acoustic sealant is applied to offer you the most effective acoustic insulation. Our applicators undergo 1 to 2 years of training and are all NVQ Level 2 certified.

Please contact us for a quote or fill out our quote form.



Stocks we install and supply

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