Insulation Archives - PLASTEK https://plastek.net.au/category/insulation/ At PLASTEK, we supply the Australian building and construction industry with premium quality insulation materials. Fri, 10 Dec 2021 09:03:32 +0000 en-US hourly 1 https://wordpress.org/?v=6.7 Compressive Strength Requirements for Insulation in Cold Storage Floors https://plastek.net.au/compressive-strength-requirements-for-insulation-in-cold-storage-floors/ https://plastek.net.au/compressive-strength-requirements-for-insulation-in-cold-storage-floors/#respond Wed, 21 Apr 2021 02:09:07 +0000 https://plastek.net.au/?p=888 Efficient thermal insulation is an important aspect of flooring in any cold storage facility. It helps to maintain the correct internal temperature and reduce energy usage. The reversal of the usual flow of heat and moisture inside to outside needs to be taken into account in the case of cold storage. Unlike regular building structures, [...]

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Efficient thermal insulation is an important aspect of flooring in any cold storage facility. It helps to maintain the correct internal temperature and reduce energy usage. The reversal of the usual flow of heat and moisture inside to outside needs to be taken into account in the case of cold storage. Unlike regular building structures, heat flows from the moist sub-soil and external environment towards the colder, drier interior of the cold storage area by diffusion through the floor and enclosure.

In addition to important factors like thermal efficiency and moisture resistance, insulation in cold storage flooring needs to have adequate compressive strength characteristics. It must be capable of bearing the load of the other floor materials as well as the dynamic and static weight of stored goods and human activity in the cold storage facility.

Assessing Compression Behaviour for Cold Storage Flooring

The ability for a material like insulation to resist the loads applied to it is assessed and declared by measuring its compression behaviour. The test method for insulation materials involves a sample being placed between two plates of the testing apparatus with different degrees of force applied. The assessed compression behaviour of an insulation material can vary depending on the test method and standards. 

In one case, it can refer to the load that compresses the insulation by 10% of its thickness, resulting in relative deformation to the original sample thickness. Alternatively, it can refer to the load “at yield”, which is the point at which the insulation material can be described to have failed before compressing by 10%. 

Importance of Compressive Strength in Cold Storage Floors

An insulation material would never be used in a situation where it could potentially compress by 10%. The consequences of that much movement could not be tolerated by any materials in the construction of cold storage flooring. Assessing compression behaviour and specifying the correct insulation for flooring is essential for safety and the correct function of a cold storage structure.

Insulated concrete slabs are a common requirement in cold storage facilities. The insulation used in cold storage floors must therefore be capable of supporting heavy loads. This includes structural loads from the floor itself in addition to stored goods and dynamic loads from things like foot traffic and heavy vehicles driving across the floor. 

Compressive Creep

Another important consideration when specifying insulation for cold storage floors is accounting for compressive creep. Long-term loading creates a progressive compression that affects different materials in different ways. The long-term effect of loads therefore requires a different measure – compressive creep. Static weight from stored goods is more likely to be the cause of compressive creep.

Unfortunately, many insulation material manufacturers don’t test for compressive creep, as it requires a testing period from 122 days to 608 days, depending on the period of years being simulated – 10, 25 or 50 years. Some manufacturers declare compressive creep as ‘compressive strength at 2% compression’ or similar since the overall compression evidenced is typically around 2%. 

Compressive Strength Characteristics of XPS Foam

XPS foam offers one of the broadest ranges of compressive strengths and is one of the few insulation products where manufacturers invest the time to test and declare compressive creep. The uniformly distributed closed cells in XPS foam give it superior compressive strength characteristics. This makes it a reliable and long-lasting solution when used in cold storage floors that must bear heavy loads. 

XPS foam also has several other characteristics in addition to high compressive strength that make it ideal for use in cold storage flooring. It has a high, stable, and predictable thermal conductivity, is highly resistant to moisture, is incredibly durable and has a long lifespan. 

Technonicol’s Carbon XPS foam series comes in a variety of sizes, thicknesses, and compressive strengths to meet the demands of any cold storage flooring specification. Technonicol’s Carbon Prof 300 and Carbon Solid 500 are ideal for cold storage flooring as Carbon Prof 300 offers a minimum compressive strength of 300 kPa and Carbon Solid 500 offers a minimum compressive strength of 500 kPa making them more than capable of accommodating the higher floor loads found in cold storage facilities. 

Related Questions

Why is water resistance so important?

Water is an excellent conductor of heat, so moisture drastically reduces the thermal performance of insulation. Moisture resistance is especially important in areas such as cold storage flooring. XPS foam insulation is a closed-cell insulation made via an extrusion manufacturing process meaning it is free of tiny voids or spacing between the cells unlike other materials like expanded polystyrene (EPS) foam. This makes it highly resistant to water absorption and water vapour transmission.

Can XPS foam withstand freeze/thaw cycles?

A closed-cell construction enables XPS foam to resist freeze-thaw cycles, which is a key requirement for cold storage floor insulation. Moisture that gets into tiny gaps of other insulating materials will shrink and expand as it goes through the freeze/thaw cycle, causing it to deteriorate and lose its thermal performance over time.

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4 Key Durability Benefits of Stone Wool Insulation https://plastek.net.au/4-key-durability-benefits-of-stone-wool-insulation/ https://plastek.net.au/4-key-durability-benefits-of-stone-wool-insulation/#respond Fri, 19 Mar 2021 04:02:35 +0000 https://plastek.net.au/?p=886 Durability is of the utmost importance when selecting insulation. It’s right up there with other characteristics such as thermal efficiency and moisture resistance. Durability ensures an insulation product works effectively and consistently while enduring over a long period. A durable insulation product for your house, for example, needs to last for the lifetime of the [...]

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Durability is of the utmost importance when selecting insulation. It’s right up there with other characteristics such as thermal efficiency and moisture resistance. Durability ensures an insulation product works effectively and consistently while enduring over a long period. A durable insulation product for your house, for example, needs to last for the lifetime of the building and will not require maintenance. 

Stone wool, also called mineral wool, is a versatile, highly durable insulation material. It is uniquely capable of simultaneously providing thermal, acoustic and fire protection. The durability and high performance of stone wool makes it useful for a variety of applications, including pitched and flat roofs, flooring and external, internal and partition walls. 

Stone Wools Meets Two Main Aspects of Durability

There are two main aspects of durability to look for in any construction material. The first is its ability to maintain a constant performance in all important aspects such as thermal, mechanical, moisture or fire resistance. It should also have a long lifespan relative to its intended function. For example, a lifespan of 50 years or more should be considered for insulation products as buildings can remain standing for many decades. Stone wool meets both these requirements.

Durability is Sustainability

A durable construction product is a sustainable one. Stone wool insulation maintains a strong performance throughout its lifetime without needing maintenance or regular replacement. It is also recyclable and made from renewable resources. This means using it consumes less resources, creates less waste and its manufacturing impact is spread over long periods of time. Durability and eco-efficiency go hand-in-hand in helping us progress towards sustainable consumption and production.

Withstand Multiple Destructive Forces

Stone wool is fire resistant, waterproof, resistant to chemicals and microorganisms, and does not enhance the growth of bacteria and mould. It is also not prone to corrosion. This makes it particularly versatile in how it’s durable. That is, it can withstand the widest variety of destructive forces compared to other insulation materials. 

Fire resistance is a key feature of stone wool that distinguishes it from alternative materials. Stone wool insulation can have a significant impact on the fire safety of a building. Importantly, the fire safety properties of stone wool insulation do not deteriorate over time. Non-combustible stone wool improves the fire resistance of construction elements, and those fire resistance properties will remain over the life of the building.

Proven to be Durable Long-Term

Real-life sampling has proven that stone wool’s thermal performance remains constant over time. This is particularly important when it comes to investing in a house. The consistent thermal performance of walls, floors and the roof is crucial to ensuring that you do not suddenly face increased bills for heating or cooling after several years of use.

The performance of insulation products is determined by its thermal resistance

(R-value). While stone wool may have a slightly higher thickness than some other insulation materials in order to reach the same R-value, the most important thing is that its thermal performance does not decrease over time. The R-value of stone wool insulation will remain stable over the lifetime of the building.

Technonicol Stone Wool Supplied by Plastek

Technonicol produces premium quality stone wool insulations for roofing, walls/facades and sandwich panel applications. The fibrous structure of Technonicol stone wool products ensure excellent acoustic and sound-absorbing properties of the material.

Related Questions

What are the benefits of stone wool over other insulation materials?

The best insulation material varies according to the unique specifications of each project. Stone wool is an incredibly effective insulation that is chosen usually because of its fire resistance, sound insulation qualities and flexible ease of use.

Is stone wool environmentally friendly?

Typically, stone wool insulation contains up to 90% recycled content. The steel and iron ore industry produce millions of pounds of slag each year. Instead of sending that material to landfills, it can be recycled into high-performance insulation. Stone wool is produced using a virtually inexhaustible natural resource. The earth makes 38,000 times more rock every year through volcanic and oceanic activity than what is extracted to produce stone products.

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What’s the Difference Between XPS and EPS? https://plastek.net.au/whats-the-difference-between-xps-and-eps/ https://plastek.net.au/whats-the-difference-between-xps-and-eps/#respond Thu, 18 Feb 2021 02:32:02 +0000 https://plastek.net.au/?p=883 The energy efficiency of a building often depends on the materials that create its envelope. Selecting the appropriate insulation type is crucial in delivering the required insulation performance for your project. Both extruded polystyrene (XPS) and expanded polystyrene (EPS) foam insulations are commonly used in construction applications. But what is the difference between EPS and [...]

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The energy efficiency of a building often depends on the materials that create its envelope. Selecting the appropriate insulation type is crucial in delivering the required insulation performance for your project. Both extruded polystyrene (XPS) and expanded polystyrene (EPS) foam insulations are commonly used in construction applications. But what is the difference between EPS and XPS foams? 

Production Process

Extruded polystyrene (XPS) and expanded polystyrene (EPS) are both foam polystyrene products used for insulation. Polystyrene is a versatile synthetic material, useful because it is inert (doesn’t react with other materials), lightweight, cost-effective, and long-lasting. When used to create foam insulation, it offers a high level of thermal efficiency and an impressive strength-to-weight ratio. 

Extruded polystyrene (XPS) is manufactured using a process of extrusion. This continuous process results in a closed cell structure that prevents water penetration to the structure of the insulation board and provides long term strength and durability.

Expanded polystyrene (EPS) insulation is manufactured using beads of foam within a mould, with heat or steam then applied directly to cause the beads to expand and fuse together. This process produces a closed cell structure but not a closed cell insulation board, as uneven voids occur between the beads. 

Compressive Strength

Compressive strength is a key requirement for challenging environments such as under slabs, foundations, and green roofs. When comparing XPS and EPS foam board densities, the compressive strength of XPS foam is typically much greater than that of EPS. For EPS foam insulation to achieve the same compressive strength performance as XPS foam, the density of the material would need to be increased.

Thermal Conductivity

Insulation is an essential and highly cost-effective way to improve a building’s energy efficiency. By improving the insulation in new and existing buildings, significant cost savings and reductions in energy usage can be achieved. Both XPS foam and EPS foam provide good thermal conductivity performance. However, the air trapped in the voids in the EPS conduct heat. XPS foam has a consistent long-term thermal resistance even in wet conditions and at very low temperatures.

Water Vapour Diffusion

Water vapour diffusion resistance (μ) of EPS foam ranges from around 30 to 70. XPS foam, on the other hand, has a water vapour diffusion resistance (μ) that ranges from around 80 to 250. This means XPS foam is better for wetter environments that require a higher water vapour diffusion resistance value.  

Moisture that gets into tiny gaps of EPS foam will shrink and expand. This significantly impacts its performance as an insulator on top of causing early deterioration. Closed cell XPS foam is water repelling and capable of withstanding over 1000 freeze/thaw cycles, ensuring long term durability at a relatively low cost. 

Technonicol XPS Foam – Resistant, Robust and Versatile Insulation

Technonicol offers thermal insulation boards made of high-quality extruded polystyrene. Technonicol’s Carbon XPS foam series comes in a variety of sizes, thicknesses, and compressive strengths to meet the demands of almost every application and is:

  • Extremely durable
  • Capable of bearing heavy loads
  • Highly resistant to moisture
  • Guaranteed to have low, stable, and predictable thermal conductivity
  • Able to withstand the stresses of temperature changes and freeze/thaw cycles.

Related Questions

What does closed cell mean?

XPS foam insulation is a closed cell insulation, meaning there are no tiny voids or spacing between the polystyrene cells. This is achieved through a manufacturing process that involves extruding the polystyrene through a die. EPS foam, on the other hand, is produced by expanding the polystyrene cell, which can lead to tiny, irregular gaps. A completely closed cell construction is essential for reducing heat transfer and resisting water absorption and water vapour transmission. 

Is XPS foam environmentally friendly?

XPS insulation is 100% recyclable and contributes enormously to reducing energy use. It lasts decades once installed, it significantly lowers the carbon footprint of the building over its lifespan.

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Specifying Insulation for Flat Roof Car Park Decks https://plastek.net.au/specifying-insulation-for-flat-roof-car-park-decks/ https://plastek.net.au/specifying-insulation-for-flat-roof-car-park-decks/#respond Wed, 13 Jan 2021 00:19:12 +0000 https://plastek.net.au/?p=878 Specifying Insulation for Flat Roof Car Park Decks   Multi-storey car parks are an essential part of every modern city. While they seem like simple constructions, a well-built, safe, clean and long-lasting car park requires particular materials and design approaches. A key part of this is preventing water ingress through the car park deck, which [...]

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Specifying Insulation for Flat Roof Car Park Decks

 

Multi-storey car parks are an essential part of every modern city. While they seem like simple constructions, a well-built, safe, clean and long-lasting car park requires particular materials and design approaches. A key part of this is preventing water ingress through the car park deck, which can lead to damp, cracked, spalling concrete, slippery floors and damaging alkaline salts dripping onto car paintwork. Good design, including using the right insulation materials, is key to ensuring a car park is well constructed.

Car Park Deck Design

 

A car park deck is essentially a type of warm flat roof. In a warm roof construction, the insulation layer is installed above the structural deck and below the waterproofing layer. A car park deck is a warm roof where the imposed loads from vehicle weights are significant, meaning the design requires an insulation material capable of bearing heavy loads while maintaining its integrity. 

 

Extruded polystyrene (XPS) foam has a number of key characteristics that make it ideal for car park decks, including superior load-bearing performance, water repelling qualities and a flat, strong and dimensionally stable base for the deck overlay. In many car park deck constructions, the insulation layer is covered by a separating layer, screed and mastic asphalt or liquid-applied waterproofing. 

Benefits of XPS Foam in Car Park Decks

 

XPS foam has a high compressive strength for specialist applications such as car park decks, heavy duty flooring and inverted roofing. It also resists water absorption and provides excellent thermal performance. Other benefits include:

 

  • XPS foam boards have a high strength-to-weight ratio, making them robust and highly durable while at the same time lightweight and easy to transport.
  • XPS foam boards are long-lasting with a service life comparable with that of a car park, building or structure.
  • XPS foam is durable enough to withstand the stress of heavy surface traffic and mechanical damage that may occur during installation and maintenance.

 

If the waterproofing layer is damaged in a car park deck, the XPS foam won’t be damaged by exposure to moisture or water. An important part of flat roof designs are the detailing and construction of suitable upstands around the roof edge. XPS foam boards limit heat loss due to thermal bridging where the flat roof joins with the external wall. 

Meeting Car Park Deck Load Requirements With XPS Foam 

 

The closed-cell structure of XPS foam gives it excellent load-bearing qualities. The material is extremely rigid and capable of withstanding both static and dynamic compression. Technonicol’s Carbon Prof 300 XPS foam offers a minimum compressive strength of 300 kPa and 500 kPa with Carbon Solid 500 XPS foam. This makes these XPS foam boards appropriate for car park decks

Technonicol XPS Foam – Ideal for Car Park Decks

 

Technonicol’s Carbon XPS foam insulation series comes in a variety of sizes, thicknesses and compressive strengths to meet the demands of almost every application, including car park decks.

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How to Insulate Swimming Pool Basins https://plastek.net.au/how-to-insulate-swimming-pool-basins/ https://plastek.net.au/how-to-insulate-swimming-pool-basins/#respond Tue, 12 Jan 2021 00:27:10 +0000 https://plastek.net.au/?p=894 To ensure energy efficiency and consistent comfortable temperatures, swimming pool basins should always be insulated around the outside of their structure. This helps with the detailing of the pool construction, from the design and installation of the waterproofing layer to establishing a consistent thermal envelope with the surrounding environment of the pool.   Extruded polystyrene (XPS) [...]

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To ensure energy efficiency and consistent comfortable temperatures, swimming pool basins should always be insulated around the outside of their structure. This helps with the detailing of the pool construction, from the design and installation of the waterproofing layer to establishing a consistent thermal envelope with the surrounding environment of the pool.  

Extruded polystyrene (XPS) foam has a number of unique features that make it ideally suited for demanding applications such as underneath pools, and as ground floor insulation in buildings. XPS foam maintains its robustness and water repelling characteristics when installed in contact with soil and can bear the weight of both concrete and water in a pool, making it the essential insulation solution. 

Benefits of XPS Foam in Pool Basins

Unlike other forms of foam such as expanded polystyrene (EPS), XPS foam is tolerant of damp or wet environments. This means it can be installed on the outside of the pool structure and tanking/waterproofing while still delivering its impressive thermal performance, even in the presence of a lot of water. 

Technonicol is a leading manufacturer of closed cell XPS foam, offering a wide range of strong, lightweight, moisture repelling and easy to cut boards. Technonicol’s Carbon XPS foam series comes in a range of sizes, thicknesses and compressive strengths to meet various project demands. For example, Carbon Prof 300 has a compressive strength of 300 kPa and Carbon Solid 500 has a compressive strength of 500 kPa, which both offer more than enough compressive strength to withstand the weight of a pool when installed underneath it.

Is It Necessary to Insulate a Swimming Pool Basin?

It’s a good idea to thermally insulate swimming pool basins regardless of whether it’s legally required or not in order to reduce the energy required to maintain a certain water temperature. This reduces energy costs and ensures pool operation is more eco-friendly. 

The Importance of Preventing Heat Loss

It’s well understood that heat evaporates from the top of swimming pools. However, the sides and bottom of the pool also lose significant amounts of heat and are often not considered by builders. Whether the pool is above-ground or in-ground, these other areas of the pool lose heat into the surrounding environment, especially when in direct contact with soil. 

Using XPS foam can prevent up to 80% of heat loss from your pool compared to not having it at all. The extra cost of installing XPS foam is easily recouped within two years of installing it simply through the energy cost savings.

What Makes XPS Foam Water Resistant?

A lifetime of exposure to retained water makes it essential that any insulation used in a swimming pool retains its R-value, possesses compressive strength and other crucial properties while exposed to water. For that reason, XPS foam is almost exclusively used for insulating the bottom of pools. Insulation materials suitable for use in building construction above ground should not be used in a swimming pool where contact with moisture would make them lose all their insulating properties, rendering them useless. 

When you use XPS foam, it’s guaranteed to work effectively and long-term in a swimming pool construction. The hydrophobic and homogeneous closed-cell structure of XPS foam is what makes it durable and highly resistant to water intrusion. It performs much better than expanded polystyrene (EPS), another plastic insulation that XPS is commonly compared to.

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How to Insulate Inverted Flat Roofs https://plastek.net.au/how-to-insulate-inverted-flat-roofs/ https://plastek.net.au/how-to-insulate-inverted-flat-roofs/#respond Fri, 08 Jan 2021 07:36:00 +0000 https://plastek.net.au/?p=873 Flat roofs are those with a slope angle of 8.5° or less. No flat roof is truly flat as there has to be a minimum fall to avert problems such as water pooling. An inverted roof is a type of roof construction where the waterproofing layer is placed below the insulation layer instead of above [...]

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Flat roofs are those with a slope angle of 8.5° or less. No flat roof is truly flat as there has to be a minimum fall to avert problems such as water pooling. An inverted roof is a type of roof construction where the waterproofing layer is placed below the insulation layer instead of above it, as in other forms of roofing.

When designing an inverted flat roof, the primary consideration is where thermal insulation is placed in relation to the roofing membrane (waterproofing layer). Choosing the right insulation ensures the final construction is durable, waterproof, long lasting and provides the necessary thermal performance. Extruded polystyrene (XPS) insulation features unique properties that make it ideal for inverted flat roofs.

Cold vs Warm Roof Construction

Depending on where insulation is placed, a typical roof construction can be described as cold or warm. In a cold roof construction, insulation lies below the structural deck and remains cold. This creates a risk of condensation which is commonly reduced by placing a ventilated space above the insulation. However, this approach is rarely used in temperate, humid climates such as those found in Australia.

In a warm roof construction, the insulation is installed above the structural deck and below the waterproofing layer. This succeeds at reducing the risk of condensation, but it means the waterproofing layer is thermally isolated from the rest of the roof construction. This exposes it to wide temperature fluctuations, potentially leading to premature failure. An inverted roof design overcomes the problems of both cold and warm roof constructions.

What is an Inverted Roof Design?

Inverted roofs, which can also be called upside down or protected membrane roofs, resolve the problems of cold and warm roof designs by installing insulation above the waterproofing layer, keeping it at an even temperature close to that of the building interior. This also protects the waterproofing from UV radiation, weathering and mechanical damage during construction, use and maintenance.

The waterproofing layer in an inverted roof design acts as a total vapour control layer and can be maintained above dew point temperature since it is on the warm side of the insulation, minimising the risk of condensation. For this design to work, you must use XPS foam insulation as it has the necessary characteristics to withstand the conditions above the waterproofing layer.

The Importance of XPS Foam in Inverted Roof Design

XPS foam insulation offers excellent thermal performance and features unique properties that differentiate it from other types of foam insulation such as EPS foam. For example:

  • XPS foam is resistant to rain, snow, frost and water vapour, enabling the material to withstand repeated freeze/thaw cycles.
  • XPS foam is resistant to acids, salts and fungus, as well as being clean, odourless and free from dust.
  • When properly installed, XPS boards have a service life comparable with that of the building or structure.
  • Due to its homogeneous closed-cell structure and uniform density, XPS foam can be cut very accurately and to very close tolerances.
  • XPS foam is durable enough to withstand surface traffic and is resistant to UV and mechanical damage that may occur during installation and maintenance.
  • The boards have a high strength-to-weight ratio, making them robust and highly durable while at the same time lightweight and easy to transport.

XPS foam is ideal when higher compressive strength, higher water resistance and higher thermal resistance in the presence of water are required. XPS foam insulation boards can be loose-laid on top of the membrane and then weighted down with paving slabs, gravel ballast or soil medium if creating a green roof.

Technonicol XPS Foam – Ideal for Inverted Roof Insulation

Technonicol’s Carbon XPS foam insulation range comes in a variety of sizes, thicknesses and compressive strengths to meet the demands of almost every application, including inverted flat roofs on large domestic, commercial and industrial buildings.

At Plastek, we have extensive experience consulting and supplying these XPS foam insulation products, helping to optimise projects by providing the ideal solutions. We can recommend the right Carbon XPS foam insulation product for your specific project, ensuring a functional and high-performance solution for your building.

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