Written by Migelo Buckley.
How much do bus and coach adhesives cost?
This will always be one of the main questions asked by any coach or bus builder when researching the options to bond or seal their vehicle. Price ultimately dictates what kind of technology and performance you get from you adhesive or sealant. This needs to be factored into the cost of manufacturing and the intended life-span of the vehicle as well as maintenance and upkeep of the vehicle.
Its difficult to answer the cost question straight off the cuff because there are so many variables in the application of adhesives and sealants in bus/coach building industry. The variables range from the substrate it is applied to, the environmental factors the adhesive will be exposed to, the individual design of the vehicle and where this places stress factors; the list could go on. Suppliers need to keep in mind the variables involved as they contribute to the ranges in the costs of the adhesive. In addition, there are some companies that have been using adhesives a lot throughout their vehicles for many years and tend to bond many more areas that other companies who have used a different approach.
At Forgeway, we seek to answer all your questions as you ask them, even if it leads you towards a different product, or a design to reduce and eliminate the use of adhesive or sealant. I’ll do my very best to offer some real-world pricing ranges, based on current costs right now (2021).
Please keep in mind that all prices are only estimates based on the average cost of adhesives, which may vary depending on factors such as the performance, the commitment to supply, geological considerations, the risk factor to the supplier, the individual company, and so on.
How much does bus/coach adhesive cost?
Most adhesives or sealants for the bus/coach market will cost between a range of £5 to £12/ kilogram in 2021. As with many products, the cost can increase depending on the amount of features that are added to the basic formula, from different curing times to different levels of performance in certain areas, like better UV resistance properties, to custom colours made in small quantities.
Where it’s applied and quantity
Where and how the adhesive is applied can differ from region to region; even within regions, depending on the design of the vehicle and accounts for a lot of the variances in costs, where different adhesives may cost more or less, depending on what is required of them.
East / South East Asia
Buses and coaches designed and built in this region reflect the market conditions and the technology readily available. Vehicles typically cost less to produce due to cheaper labour and materials, as well as utilising more traditional construction methods like fastenings. However, some manufacturers use adhesives:
- Decorative cladding: one area that often uses adhesives is decorative cladding, where the cladding is not a structural or safety critical part of the vehicle. The adhesive used is often of lower performance and low cost, costing around £5/kilogram.
- Sealing against water ingress: not being structural or safety critical costs are around £5-7/kilograms, depending on whether the adhesive will be exposed to weathering for example UV as opposed to filling openings deeper in the architecture of the bus.
In the European/North American market, the use of adhesives is more widespread with vehicles having a higher quality of build as well as utilising different materials in their manufacture. Materials like fibre reinforced plastics are commonly used and the vehicles are often designed from the outset to utilise adhesives in a structural and safety critical way.
- Staircases (double deck buses): higher strength adhesive for about £7-10/kilogram, which can vary depending on the amount of extra performance and characteristics. For example, the ability to bond to a LSE composite might increase the costs further.
- Interior panels adhesive: can cost between £7 and £10, depending on whether the adhesive will be visible and thus exposed to conditions such as UV light, which may drive up the cost. In addition, the customer may require the adhesive to be colour matched, increasing costs further.
- Exterior panels: cost of bonding is between £7 and £10/Kilogram as the adhesive is semi-structural in nature and may be exposed to ranges in temperatures and stresses, for example a collision with an object.
- Other large body panels bonded to the frame also use similar high strength adhesive, costing between £8 and £11. This is because the adhesive has to be able to adhere to a range of GRP/FRP materials /other composites with low surface energy, increasing the costs and complexity of the task as well as risk to the supplier.
- Roof sections may feature different types of adhesive, from the structural adhesive costing between £7 and £11/kilogram, to sealing adhesive as well as decorative sealants that could be specifically colour matched or be resistant to UV light etc.
- Windows are a safety critical element of the bus and this is reflected in the cost, where it ranges from £8 to £12.
- Sealing/backfill adhesives can cost between £6 and £9/kilogram, again depending on whether there are special requirements. For example, colour matched to the substrate/decal colours to achieve a seamless look. However, as with specially coloured sealants and adhesives, prices may vary even more depending on the difficulty of matching the colour.
Risk to supplier
Costs can also be driven up not only by the materials involved in the build, for example a Low Surface Energy Plastic (LSE), but also from the perceived risk to the supplier where their adhesive might be used in a safety critical or structural application.
An example of this is if the adhesive was being used to bond a coach side window. The risk of a passenger falling out of a coach or bus if a window falls out is significant, making it a safety critical part of the vehicle. As a result of this the supplier will charge more to compensate for the increased exposure to risk this places them under, meaning the adhesive may jump in price significantly (even if its performance does not increase when compared to another product from the same company). As a result of this, there may be fewer competitors in the market, and the lack of competition may keep prices higher.
Everything in this article is based on estimates and approximations where real life figures and amounts may differ from those in this article. Figures may differ significantly with the COVID-19 disrupting the market, where prices have rising by large amounts as the costs of raw materials have also increased. However, I hope this has give you a rough idea on the typical costs of adhesives that are used in bus and coach manufacturing, and you can look at the options presented on the market to compare to average prices.
If you have any questions as a result of reading this, feel free to contact one of our specialists for some non-biased advice.