Polyester vs Glasswool


An investment for the life of your home

Insulation is an investment in the future comfort and energy efficiency of your home. When deciding on a brand and type of insulation, you need to ask yourself some key questions. We hope this article will help you to make an informed decision.

What is insulation made of?

Glasswool insulation most common

Most insulation brands sold in New Zealand are made from glasswool, also known as fibreglass. Glasswool has numerous benefits which make it such an effective insulation material. Because its main ingredient is recycled glass and sand, it can’t catch fire, does not attract vermin, doesn’t rot, and isn’t prone to absorbing airborne moisture. It is fairly easy to cut with a sharp knife, and quite simple to install. The millions of tiny air pockets give glasswool its fantastic insulating properties.

So what about polyester insulation then?

Autex GreenStuf manufactures insulation made wholly from polyester. Polyester insulation has practically all the above mentioned benefits, and it also has some additional benefits. It contains no breathable fibres. This may be significant for asthma sufferers or those suffering from serious dust allergies. However, here it’s important to point out that in an old ceiling, there is likely to be a lot of dust anyway – regardless of whether or not there is insulation in the roof space, and regardless of whether any insulation installed is polyester of glasswool. But it would be fair to assume that if all other factors were equal, polyester would be the least dusty alternative, particularly in a new building.

How much does it cost to insulate a house with polyester insulation?

In this example we’ll compare glasswool with Autex GreenStuf, which is manufactured from 100% polyester. Many people who installed insulation back in the day will have memories of working with near unbearable products and for them polyester insulation is the only option, even though it is a lot more expensive. They argue that no price is to high to work with a product that is completely itch free. In fact, you can almost sleep in the stuff! No amount of convincing about technological advances in glasswool production will get them to change their mind. To them it’s GreenStuf or no stuff!

Huge difference in delivery costs

The key difference worth noting if you’re planning to order insulation, is the cost of getting it delivered. Polyester is typically a bulky product when compared to glasswool. If you live in or near one of New Zealand’s major cities, this will probably be of little concern. However once you move away from the larger centres such as Auckland, Wellington, Christchurch, Hamilton and Tauranga then delivery can start becoming costly. For example, if you have a 130m2 ceiling, and you plan to insulate it with R3.6 Earthwool Glasswool Ceiling Insulation. This will easily fit onto one pallet, whereas you would need around 4 pallets (or pallet spaces) to ship the equivalent R3.4 GreenStuf Polyester Ceiling Insulation. In practice this means you might quickly find yourself needing to factor in an extra 30% – 40% of the material’s cost simply to cover the freight costs, especially if you live in a remote area. With glasswool, in most cases the delivery fees will be more be in the order of 10%- 20%. These are not exact figures, but can provide a helpful indication.

Summary and conclusion- glasswool vs polyester segments

  • Polyester is exceptionally soft to handle and has no dusty particles, making it a particularly attractive option for allergy sufferers
  • We recommend you use our website shopping cart to calculate the cost of both options, and confirm the delivery cost with us if you live outside the major cities.
  • Then compare the difference, and determine whether the extra cost of the polyester option is justifiable.

If you need more advice, don’t hesitate to contact us.

Pink Batts vs Earthwool Glasswool


So which product is actually better, when you compare Pink Batts vs Earthwool Glasswool? Well that may depend on what’s most important to you.

Pink Batts vs Earthwool Glasswool

What is insulation made of?

First let’s look at the similarities. Both Pink Batts and Earthwool Glasswool are “glasswool” insulation products, and in large part made from sand and recycled glass bottles. Both Pink Batts and Earthwool Glasswool insulation segments are available in a variety of “R-values” to suit different climates.

The benefits of insulation are the same

When comparing Pink Batts vs Earthwool Glasswool it’s important to realise that once the insulation is installed, the thermal benefit is practically the same. So an R2.0 wall insulation segment will give you the same thermal protection, regardless of whether it is branded Pink Batts or Earthwool, or any other brand for that matter. Pink Batts comes with a “life time guarantee” and Earthwool comes with a standard 50 year guarantee, which in practice means you can expect the insulation to last as long as your home.

Storage and Handling

Earthwool Glasswool Insulation has gained popularity in recent years primarily for two reasons. Firstly, it uses a different binder, which makes it less itchy to work with. This is a real plus for DIY home renovators, not to mention professional installers who work with insulation on a daily basis. Secondly,  Earthwool comes in a highly compressed packaging, which can significantly reduce the need for on site storage space, and also help to reduce freight costs if you’re paying the full cost to get the insulation delivered to your home or on site.

Convenience and Flexibility

Earthwool insulation will typically need to be shipped out in in large bales, which can be inconvenient in particular for small owner-builders. For this reason many customers prefer Pink Batts, as there is no minimum order quantity and local pickup and delivery is available practically anywhere in New Zealand.


Ceiling insulation in Auckland- What R-Value?


Auckland’s climate is characterised by pleasant warm summers and cool winters. When the weather outside is even just a few degrees hotter or colder than your preferred indoor temperature, then the solution is thermal insulation.

Ceiling insulation R-Value matters

Without ceiling insulation, the indoor temperature will ‘follow’ the outside temperate, and even with a heater on, you will likely find yourself struggling to maintain a comfortable indoor temperature, especially on chilly winter evenings. The solution is ceiling insulation with a sufficient R-Value. Bulk insulation such as glasswool and polyester contains millions of tiny air-pockets. These drastically slow down the heat transfer process, which is how insulation works. A thicker insulation segment will have a higher R-Value, and will be more effective.

Analysis: Benefits of insulation vs cost

Doubling the insulation R-Value will not double the energy efficiency of your home. The law of diminishing returns is very applicable here. And it’s not a fixed equation either – should energy prices skyrocket a few years down the track, then there may be many home owners wishing that they’d installed a higher R-Value at the time. We are frequently asked, ‘How much does it cost to insulate a house?’ The real question, however, considering energy prices on the rise, is ‘How much will it cost me NOT to insulate a house?’

What we recommend at Pricewise Insulation

As a rule of thumb, if you’re building a new home or installing ceiling insulation in a new home in or around Auckland, we recommend R3.6 or higher. This is typically around 17cm thick, and provides a good level of thermal protection. Upgrading to an R4.1 or above will moderately increase the energy efficiency of your home, and could also result in real $$ savings if energy prices continue to rise.



A Perspective on Noise in the Home

Living in a fast-paced world

“All you teachers ever say is ‘hurry up!’” an innocent Year 1 student remarked one day, little realising that he had just summed up the plight of human beings living in the 21st century. He’s right. In our frenzy to get things done, meet deadlines and pay the bills, everything is in fast-forward mode. If there was ever a time where peace of mind was sought after, it’s now.

People are constantly bombarded with messages from every side, demanding anything and everything of them, and then wonder why they’re falling apart. Yet they never give their minds a break. Background noise has become so normal that people don’t realise how little time they spend listening to nothing at all. However, just like your body physically needs to stop, your mind needs regular breaks from all the commotion around you. Down time. Nothing time.

Noise! Noise! Noise!

“Turn it down!” “You always tell me what to do!” “I’m trying to study!” “It’s not your house!” Music plays a huge part in most teenagers’ lives, but can also be a major point of conflict between parents and their children and between siblings themselves. Everyone is trying to live their life in one space. Everyone has their needs. Tastes differ. Vastly. In the end the family compromises, but nobody is really satisfied; the teenager’s music is not loud enough for him to enjoy, but still too loud for the other family members.

Then it wouldn’t be surprising if children started being diagnosed with “LND – Loud Noise Disorder” in the future or something along those lines. Actually, they’re just kids. They talk, they laugh and yes, shouting is also quite normal for a child. Children haven’t changed. But in our fast-paced world where stress and anxiety are on the rise, many adults are finding it more and more difficult to cope with the racket their children create, no matter how normal it is.

And then there’s the baby. “He just cries every night! I don’t know what to do!” Rachel, a mother of three children under four years old, lived in a three bedroom townhouse. Every night she would put the kids to bed after a busy day of entertaining them, sorting out squabbles and managing the housework. She loved her kids, but admitted that she was very tired and that the only thing she wanted was quiet. Yet, every night she would find herself sitting down and just waiting for the crying to stop.

The benefits of insulation in the home

“Moving to a new, properly insulated house was the best decision we made!” says Rachel. “Now we put the kids to bed at one end of the house and enjoy the peace and quiet in the comfort of our living room at the other end.” She says she’s stopped thinking there’s something wrong with her baby and realises that he just needs to cry a little before he goes to sleep. She says that if you can’t hear it, it’s not there. Anyone for a cup of tea?

Building a new home, or renovating? Acoustic sound insulation helps to control noise within the home. For your peace of mind, contact Pricewise Insulation about an acoustic insulation solution..

Insulation Segments vs Rolls


If you’re installing ceiling insulation in an existing home, then two common alternatives are insulation segments, and insulation rolls.

Insulation segments vs rolls – is one better than the other?

The short answer is no – both products are equally effective in insulating your ceiling space. The main difference is the method to install the insulation. While rolls can be ‘rolled’ out between the ceiling joists, insulation segments are installed in pieces. If you are installing insulation across the joists to eliminate thermal bridging, and if your ceiling space has very few obstacles and a lot of room to work in, you may find that installing rolls is a suitable option. However if you have a tight ceiling space and have some additional obstacles such as ventilation pipes or electrical cables, then you will find it easier to install insulation segments.

Buy Now! Ceiling Insulation

There is an argument which suggests that rolls are better because there are less ‘gaps’ for air to escape through. This is hardly relevant. In fact, if the insulation segments are installed correctly with a snug fit, there will be no noticeable difference in the performance of the insulation. No matter which product or brand of insulation you choose to install, remember how insulation works: it provide a thermal barrier between the outside environment and the living area inside the house.

Our verdict – Insulation Segments vs rolls

In most situations, we would recommend insulation segments as the best and most cost effective option. Knauf Earthwool Glasswool Thermal Ceiling Insulation Segments are a fantastic option.  They come in compression packed bags, saving you time on getting the insulation into the ceiling. Once you have got the bags up there, split them open one at the time, and install all the pieces from the first bag before opening the next bag. If you would like to add an extra layer of insulation to your roof space, then consider installing the Knauf Earthwool Glasswool Thermal Ceiling Insulation Rolls.

If you need more advice on your home insulation project please contact our friendly team.

Buy Now! Ceiling Insulation

Reflective Foil Wall Wrap – is it necessary?


Have you ever driven past a new housing development and wondered why the frames of some houses are wrapped with a foil and others appear to have missed out?

Opinions vary as to whether wall wrap is a must, or whether it can be considered an optional extra. Typically, in very hot and humid climates, it is given more priority, and in colder windier climates it is also commonly installed.  In more moderate climates it is often not prioritised mainly in order to save on cost.

Wall wrap: how insulation works

Wall wrap insulation serves two main purposes:

  1. It protects the inside of the building from wind, moisture and dust, effectively sealing it off from much of the elements
  2. Reflective foil insulates the home by stopping almost all radiant heat transfer.

Buy Now! Wall Wrap Insulation

Don’t forget the air-gap

Most new homes are installed with thermal bulk wall insulation in the wall cavity. All reflective foil insulation requires an air-gap of around 25mm in order to insulate effectively against radiant heat transfer. Since wall insulation is typically installed with the reflective side inwards, it’s important to consider what the main purpose of the wall wrap is. If you push the wall segments between the studs so that they come into close contact with the reflective side of the foil, this will render the effective R-Value of the wall wrap to almost zero, even though you will still benefit from the wind and dust deterring properties of the wall wrap insulation. Understanding how insulation works helps you get the most out of your insulation investment.

Maximising thermal benefits of insulation from reflective wall wrap

If a primary reason for installing wall wrap is to keep the house cooler in summer time, and assuming that you will be installing at least some thermal bulk insulation in the wall cavities, here are two alternative options which you can consider.

  1. Install the bulk insulation so that it doesn’t come into contact with the wall wrap. It requires extra care during the installation process, and depends to a certain extent on the wall studs being evenly spaced (to avoid the wall segments slipping towards the wall wrap or even leaning against it.)
  2. Alternatively you could install the wall wrap with the reflective size facing outwards. This may cause inconvenience during the bricklaying or cladding phase, especially during sunny weather, so make sure you consult with any tradespeople beforehand who might be affected by the excessive glare, so they can take proper sun-protection measures.

 Buy Now! Wall Wrap Insulation

Topping up Insulation


If your ceiling has no insulation, then installing even a relatively low R-Value such as R2.7 ceiling insulation will make a considerable difference to indoor temperature stability.

Existing insulation in the ceiling space?

The situation is quite typical. The house you moved into years ago was supposedly insulated. But you don’t feel that it is very effective, so one day you grab a torch and a ladder and pluck up enough courage to stick your head up through the manhole and into the ceiling space to have a look around. If the house was insulated several decades ago, then even what might have been considered a good quality product at the time, might now be delivering less thermal benefit than it was originally specified to deliver.

How insulation works: the compression-over-time factor

Blow in insulation, wool insulation, paper insulation and most other types of bulk insulation will settle and compress over time. Why does this matter? Because of how insulation works. Insulation is full of tiny air-pockets. The more the insulation is compressed, the less effective it becomes in reducing the transfer of heat, i.e. the effective R-Value is reduced. So what may have been sufficient 20 or 30 years ago, might no longer be performing as it was designed to, especially considering the steady rise in electricity prices over the last couple of decades.

Buy Now! Thermal Ceiling Insulation

What to do with the old insulation?

If cost was not a factor, then the advice would always be to vacuum out the entire roof space, and install new clean insulation segments, which can reasonably be expected to last as long as the house itself. However for most households, costs is of course a very real factor, and the cost of getting in a professional company to vacuum out the roof space will often exceed the cost of installing new insulation. Before deciding whether to top up existing insulation with new insulation, consider the following points:

  1. all old insulation will have some R-Value
  2. old insulation is typically extremely dusty and will often smell
  3. how much effective R-Value it still has will depend on how well it was installed originally, and how much it has compressed over time.
  4. It’s more difficult to get a neat finish when topping up old insulation with new insulation
  5. New insulation (at least the brands we sell) does not attract vermin, however many older insulation types do become nests for vermin.

Summary – topping up existing insulation

If your house currently has a properly installed and quality insulation in the ceiling, but it requires a higher R-Value, then topping up with an additional layer of thermal insulation may be a viable alternative.

On the other hand if what has been installed in the past is of a very poor quality, and in addition is distributed unevenly, then we definitely recommend you to consider cleaning out the ceiling and replacing it with new insulation in the required R-Value.

Buy Now! Thermal Ceiling Insulation


Theatre Room Insulation


What is sound insulation and which rooms should have internal wall acoustic insulation?

Sound (or acoustic) insulation for walls within the house helps to reduce the transmission of sound from room to room by absorbing the vibrations that would otherwise have passed through.

There are many good reasons to install internal wall acoustic insulation (also referred to as sound insulation or sound proofing insulation) in the home. There is no single formula to determine which rooms should and shouldn’t be insulated with sound insulation, but understanding how insulation works acoustically can help you decide which rooms to prioritize.

Soundproofing internal walls of theatre rooms and TV rooms is a must. If the theatre room is connected to the outside wall of the house, think about your neighbours and consider replacing normal thermal insulation with a hi-density wall insulation. Without acoustic insulation in the internal walls the noise emanating from the theatre room will potentially dominate the whole house when the room is in use.

Where to buy insulation for your home

Visit the Pricewise NZ insulation webshop to purchase acoustic insulation at discount prices. A great product to consider is Knauf’s Earthwool R2.8 Super Hi-Density Acoustic Wall insulation. At Pricewise Insulation, we can deliver insulation directly to your door. Deliveries are typically made within 2 – 4 business days to major cities (Auckland and Christchurch). We also ship to other cities and regional areas, but you should allow a few extra business days for remote and regional deliveries.

Buy Now! Acoustic Wall Insulation


Need Earthwool Insulation delivered in Christchurch?


Need insulation urgently?

We can deliver Earthwool Glasswool thermal and acoustic insulation direct to your door or to site as early as the next business day in Christchurch.

Why Earthwool Glasswool Insulation?

Knauf’s range of Earthwool Glasswool insulation is gaining popularity all over New Zealand wide with both commercial builders, home builders and DIY renovators. Earthwool insulation has two notable benefits:

1. Less itchy than other common brands of glasswool insulation

2. Compression packaged – more m2 coverage per bag means less storage space and handling required and it’s also cheaper to transport.

Modern day glasswool insulation has improved significantly compared to what was commonly installed some decades ago. For a reasonable fee, we can deliver Earthwool Glasswool ceiling insulation, external wall insulation, acoustic and underfloor insulation segments and rolls straight to your door throughout Christchurch and all the surrounding suburbs.

What is r rating for Christchurch area?

Christchurch has a temperate climate, but overnight frost is common in winter. This should be taken into account when deciding which insulation R-Value to go with. New homes will generally be specified as requiring a certain minimal R-value to meet energy efficiency requirements. If you’re doing a minor renovation or adding insulation in an old house, we would usually recommend a minimum R2.0 in the walls and R4.0 in the ceilings. An adequate layer of thermal insulation will keep your house cooler in summer and warmer in winter, and noticeably reduce the load on any heating and cooling appliances.


Where to buy insulation in New Zealand


At Pricewise Insulation we look after your needs

Pricewise Insulation is more than just our high quality products at discounted prices. Our reputation is built on friendly service and customer convenience. Insulation is a bulky product and if you need more than just a few bags, you’ll likely need a ute or a trailer in order to pick it up. With this in mind, we charge a discounted fixed fee of only $100 to deliver any quantity of insulation to your door within 2-4 business days to major cities. Delivery to other towns and regional centres varies. Feel free to contact us for a quote.

If you add up the time and cost of driving to pick up the insulation yourself, you may find it far more economical to place your order online and get it delivered by our couriers, than to organise your own vehicle and trailer if required and making the trip yourself.

However if you prefer to pick up, give us a call on 0800 697 742 to confirm your order and arrange a pick-up time.

Buy Wall Insulation Buy Ceiling Insulation Buy Underfloor Insulation