WHAT IS THE ALTERNATIVE TO KINGSPAN K5?*
In the realm of insulating external walls in the UK, our choices boil down to three main options: EPS polystyrene, Mineral wool, or Kingspan K5 phenolic board. While Kingspan is renowned for its superior thermal properties, it does come with a price tag, and locating it nearby can pose a challenge. So, is there any alternative to Kingspan K5? This article will address that question, helping you discover if there's a comparable product available. Let's dive in.
KINGSPAN KOOLTHERM K5 INSULATION BOARD PRICE
Typically, when we start searching for alternative products, usually price becomes a significant consideration. Premium products like Kingspan K5 externall wall board boast the best thermal properties for a given thickness, but this excellence comes with higher production costs. The most common choices when opting for Kingspan K5 are either 25mm or 70mm in thickness.
Surprisingly, even with just a 45mm gap, the prices are very different.
For example, a 25mm thick one costs about £24 per square meter, but if you go for a 70mm thickness, it goes up to £37 per square meter. If we multiply these costs by the average size of square metres typically treated on houses in the UK, it turns out to be almost twice as expensive. It's important to remember that when you're insulating external walls, the costs for items like basecoat, reinforced mesh, profiles, and render stay the same. So, the apparent cost savings for a 25mm thickness might be misleading.
A 70mm Kingspan K5 thickness offers excellent thermal conductivity at 0.021 W/mK. With an R-value of 3.50 m²K/W at this thickness, it results in an incredibly low U-value of 0.28 W/m²K. This U-value is notably low, especially when compared to similar products like EPS polystyrene, which has a U-value of 0.38 W/m²K at a thickness of 70mm (lower values are better). Hence, the price of Kingspan K5 is not only a result of its different manufacturing technology but also stems from its significantly higher quality compared to alternative products.
In summary, the cost of purchasing Kingspan K5 for external wall insulation on a 100m2 area would, therefore, be £2400 for the standard thickness and £3700 for the thickest option.
KINGSPAN KOOLTERM K5 INSULATION WALL BOARD NEAR ME
Kingspan is a highly reputable and well-known brand in the UK market. Company earned an outstanding reputation due to its dedication to the technological production process and its emphasis on customer care. One might assume that Kingspan products should be readily available near me, right? Unfortunately, that's not always the case. There are regions in the UK where a specific insulation thickness is rarely used, and sometimes it's simply not available. So, it might happen that you can't just pick up the product off the shelf.
In such situations, online stores come to the rescue, delivering materials straight to your location from the nearest available source. We are one of those online stores. If Kingspan K5 products are not within our standard delivery range, we can arrange pallet shipping, making it convenient even if you are outside our regular delivery area.
KINGSPAN KOOLTERM K5 INSULATION WALL BOARD INSTALLATION GUIDE
Kingspan K5 boards consist of a glass paper outer layer with rigid foam insulation. Due to this structure, it's crucial never to rasp these boards. The challenge lies in achieving a dead-flat and level surface, given the inability to rasp.
To address this, careful application of adhesive is essential.
Using a long spirit level ensures consistent coverage by notch troweling the entire back of the board. When fixing it to the wall, the spirit level comes in handy to ensure all boards are level with no discrepancies.
To install Kingspan K5 to an external wall, you can use either a water-mixed powder adhesive or Styrofoam (polystyrene) adhesive foam. Both methods have their pros and cons. Using adhesive to bond Kingspan K5 is much slower but allows for levelling and adjusting the boards. On the other hand, using foam adhesive is a faster method but does not allow for board adjustment, so it is more suitable for flat surfaces.
Regardless of the bonding method, it is recommended to start the installation by installing a base track, which sets the level, protects the bottom of the cladding from rodents and mechanical damage. The base track for Kingspan K5 is secured with 8-10 screws per 2.5 meters and connected using base track clips.
When installing the first layer of Kingspan K5 boards, pay special attention to the level and vertical alignment of the boards. Incorrect installation of the first layer can lead to errors accumulating in subsequent layers. Once the first layer is glued, start the second row with an offset of half the length of the board, similar to laying bricks. This installation method ensures proper alignment of joints and provides long-term maintenance-free performance.
During the installation of Kingspan K5 boards around windows and doors, avoid joints between the boards. If unavoidable, reinforce the joints with a mesh at a 45-degree angle.
Once the Kingspan K5 boards are attached, they can be fixed with anchors the next day after the adhesive has dried. Anchoring the boards on the same day could distort them. For mechanical installation of Kingspan K5 boards, use fixings of sufficient length, such as plastic or metal pins. It is recommended to use fixings at least 40-50mm longer than the thickness of the K5 insulation.
Drill approximately 8 holes per square meter with a diameter of 8-10mm, depending on the diameter of the fixing. Use a hole router to drill holes for anchor heads to be countersunk during installation. It is imperative not to mount Kingspan K5 boards without pre-drilling holes for anchor plates. The boards are relatively hard, and driving them into the core without pre-drilled holes will likely be impossible.
Once the fixings are embedded in the insulation, cover their plates with dowel caps and level them with the wall surface. The prepared surface is ready for applying a basecoat, reinforcing mesh, and the final thin-layer plaster.
KINGSPAN KOOLTERM K5 25MM
The 25mm Kingspan K5 is the most commonly chosen insulation thickness for external building insulation. It may be hard to believe, but as many as 4 out of 10 of our customers opt for this particular thickness. This choice is likely influenced by the price and the maximum insulation thickness applicable to their specific conditions. The 25mm thickness is the thinnest and most optimal for providing minimal insulation to the external walls of buildings. With a relative R-value of 1.17m²K/W, this thickness yields a relatively low, meaning good, U-value of 1/1.17 = 0.85.
For comparison, if the same thickness of an alternative product, such as Styrofoam, were used, the U-value obtained would be around 1.53, which is twice as high (higher values are worse).
KINGSPAN KOOLTHERM K5 50MM
The 50mm Kingspan K5 is the next available thickness of phenolic insulation for external building insulation. It is important to emphasize that this thickness is highly versatile, as it falls within the range of 100mm, which is the extent of most roof overhangs. Therefore, it will not protrude beyond the eaves, ensuring that water will never penetrate beyond its surface.
The 50mm Kingspan K5 provides a U-value of 1/2.5m²K/W = 0.4. This is a truly good level of thermal insulation considering the thickness is only 50mm.
To illustrate this further, it would be beneficial to compare this value to an alternative product for external walls, such as rockwool DD with a thickness of 90mm. Only at this thickness of 90mm would the rockwool DD provide the same U-value, precisely 1/2.49m²K/W = 0.40.
ALTERNATIVE PRODUCTS TO KINGSPAN KOOLTERM K5 WALL BOARD??
If, for any reasons, whether due to cost or availability, we decide to explore alternative products to Kingspan K5 wall board, it is important to note that the options are somewhat limited, essentially revolving around two main insulation products.
The insulation products for external walls that can be considered as more economical alternatives to Kingspan K5 are Expanded Polystyrene (EPS) and Rockwool DD mineral wool.
It's important to highlight that these alternatives don't provide the same level of insulation, and they won't give the exact U-values with the same thickness as Kingspan K5. In simpler terms, we can call them alternative options if we use a thicker insulation that gives similar R-value or U-value.
Below is a comparative table with Kingspan K5 for reference.
Tab.1 Comparison table of externall wall insulation products
As indicated in the table, Kingspan Kooltherm K5 wall board boasts the lowest thermal conductivity, around 0.022 W/mK, making it the top-performing insulation product for external walls in its class. However, it is moderately challenging to install, and it cannot be rasped as it is covered with white tissue.
On the other hand, Grey Polystyrene appears to be the closest alternative; however, its thermal conductivity is higher at 0.031 W/mK. This would necessitate the use of a thicker insulation layer, which may not always be possible. Additionally, its fire resistance class is E-F.
Rockwool DD on other hand is A1 class insulation designed for external walls. Rockwool DD is fire-resistant, and its structure allows the building to breathe. It should never become waterlogged during or after installation. While it can be somewhat irritating during installation, it is incredibly popular for soundproofing homes, especially when trying to reduce noise from a busy street.
CONCLUSION
When it comes to a direct alternative to Kingspan Kooltherm K5, there isn't one available on the market. The term "alternative product" applies only when its thickness is the same or similar, and it possesses identical thermal properties. Neither of the products, be it Grey Polystyrene or Rockwool mineral wool DD, matches the thermal conductivity of Kingspan K5. Achieving similar performance often requires doubling the insulation thickness, which increases costs and sometimes ends up being more expensive than using the premium board, Kingspan K5.
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The information in this blog isn't expert advice and shouldn't replace talking to the right specialists. Before buying or deciding anything based on this info, it's best to contact the product manufacturer directly to double-check if it's right for what you need.
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