Frequently Asked Questions

Insulation performance is measured in 'R values', – 'thermal Resistance'. The thermal performance of equal R value rated products is the same. Eg R2.6 Terra Lana has the same thermal resistance as R2.6 Fibreglass. However, thermal resistance is not all there is to insulation performance – Terra Lana wool blend insulation has been independently tested to show that it interacts with changing moisture levels enabling it to act like a thermal mass.

For further advantages and more comprehensive explanations of the above, go to 'Why Wool'.

Generally speaking the thicker the insulation, the higher the R value. However the insulation's R value will decrease if it is squashed (decreases the amount of trapped air) so it is particularly important in wall cavities that the nominal thickness of the insulation does not exceed the height of the studs.

Wool "breathes" as it absorbs and releases the moisture within the home. It helps remove the damp chill in older homes and reduces condensation and mould in damp environments (kitchens, bathrooms). The amazing thing is the water molecules are held inside wool fibre, leaving the insulation dry to touch. Inert mineral and synthetic fibres do not have this property and therefore do not handle rapid changes in temperature and moisture nearly as well.

Terra Lana natural wool insulation is manufactured by laying fine layers of wool together in the same direction and bonding them at elevated temperatures. This makes it easier to tear or cut the rolls into slabs in a crosswise direction.

Most of the wool is recycled waste (off cuts, pit waste) from carpet and textile manufacturers. Occasionally this is supplemented by low grade virgin wool (bellies, pieces). Wool has the same insulation properties regardless where it has come from.

1. All Terra Lana's core products are BRANZ appraised. BRANZ is a leading NZ authority on building product quality. Not all insulation brands have BRANZ appraisals (or an equivalent certification).

2. Terra Lana uses melt bond polyester as the bonding agent. This was the preferred method of bonding developed by the Wool Research Organisation of New Zealand in the 1990s. Other brands may use industrial resin, the other method WRONZ developed, but disgarded because it is less environmentally friendly, potentially breaking down over time and with inferior structural integrity.

3. Terra Lana has at least twice the manufacturing capacity of any other wool insulation manufacturer in New Zealand, meaning you are most likely to be able to get product when you want it.

4. Terra Lana has superior pricing due to economies of scale and the ownership of our own blending and manufacturing facilities.

1. The large wool component makes it more environmentally friendly than other underfloor products.

2. Terra Lana's underfloor bales are smaller than any of it's competitors. Small bales are easier to get down through man hole covers and move around underfloor. The insulation need not be unpacked so it's faster to get to the point of install and the product is protected right up to the time of installation. The stiffer polyester layer protects the integrity of the insulation if it is snagged on the ground or piles.

3. Terra Lana's wool/ polyester laminate easily accommodates varying joist widths and does not require exact cutting for friction fit (eg Expol).

4. Terra Lana's underfloor rolls are stapled to the joists meaning you will never have to worry about them coming loose and falling out.

5. The denser layer of polyester minimizes sagging underneath the floor which can be a problem with single density polyester products.

YES! Gaps between the timber and the insulation can make a big difference to the R value. BRANZ testing reveals R2.8 insulation with a gap of 16mm reduces to R1.4. That's half the nominal R value! Therefore it is very important to ensure the slabs fit snugly amongst the timber framing.

Terra Lana's 2 x R1.9 double layer works better than single layer options in ceilings with a low roof angles because a 25mm gap is required between the roof and the insulation. The bottom layer can be pushed right out almost to the wall join with the second layer finishing further back. A single layer must finish before it touches the roof, leaving an uninsulated area around the outer ceiling.  Terra Lana specialises in manufacturing double layer solutions.

If the existing insulation is level with the top of the joists then one blanket over the top of the joists and existing insulation will be fine to prevent thermal bridging. However if the existing insulation has sunk below the top of the joists, a blanket straight over the top will create a tent effect at the joists. The resulting gap will allow air movement and therefore heat loss.

Terra Lana natural wool insulation absorbs and desorbs moisture so contact with Laser Frame is not a problem. In fact it is an advantage as the wool's sorbancy ensures any moisture present is not available to be taken up by the Laser Frame. It is IMPORTANT however to follow the TERRA LANA installation instructions and ensure that the insulation is dry before installation.

If you have existing insulation that has slumped (sunk below the top level of your joists), you are best to top it up (between the joists) then lay a second layer perpendicular across the joists.This eliminates any gaps (preventing air movement and heat loss) and prevents thermal bridging (heat loss through the joists, which only have an R value of 0.8). Use Terra Lana's R3.8 double blanket product (2 x R1.9).

Terra Lana natural wool insulation does not "sweat". Wool can absorb moisture up to a quarter of its own weight as a vapor (not as a liquid), hold it within the fibres then release it as the relative humidity decreases. Synthetics and fibreglass do not have this ability and any entrapped moisture is likely to be present as a liquid or "sweat", which can lead to mould of mildews.

Terra Lana natural wool insulation does not "inflate" or "deflate". After removal from its bale the batting recovers to its nominal (manufactured) thickness. This is a natural process which may take up to 3 months. It can be sped up by giving it a shake hence our strong recommendation is that all rolls and slabs are shaken as they are installed.

Terra Lana's rolls can generally be installed faster than cuts (slabs). The wool roll can be easily ripped cross ways by hand, negating the need for cutting. Gaps can be quickly filled by ripping sections from the end of the roll.

Terra Lana uses recycled wool treated for insect resistance. Bioassay tests undertaken by AgResearch gave satisfactory insect resistance to common clothes moths.

Landscaping Questions

Nullam accumsan lorem in dui. Etiam sit amet orci eget eros faucibus tincidunt. Aenean massa. Aenean ut eros et nisl sagittis vestibulum. Donec vitae orci sed dolor rutrum auctor.

Cras varius. Suspendisse non nisl sit amet velit hendrerit rutrum. Sed mollis, eros et ultrices tempus, mauris ipsum aliquam libero, non adipiscing dolor urna a orci. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Fusce id purus. Nunc nec neque.

Nam at tortor in tellus interdum sagittis. Aliquam eu nunc. Donec elit libero, sodales nec, volutpat a, suscipit non, turpis. Curabitur suscipit suscipit tellus. Cras varius.

Praesent venenatis metus at tortor pulvinar varius. Proin faucibus arcu quis ante. Vestibulum volutpat pretium libero. Aenean leo ligula, porttitor eu, consequat vitae, eleifend ac, enim. Etiam vitae tortor.

Mauris sollicitudin fermentum libero. Proin faucibus arcu quis ante. Praesent congue erat at massa. Suspendisse feugiat. Curabitur at lacus ac velit ornare lobortis.

Duis vel nibh at velit scelerisque suscipit. Phasellus nec sem in justo pellentesque facilisis. Phasellus nec sem in justo pellentesque facilisis. Ut leo. Pellentesque posuere.

Cras sagittis. Cras ultricies mi eu turpis hendrerit fringilla. Pellentesque egestas, neque sit amet convallis pulvinar, justo nulla eleifend augue, ac auctor orci leo non est. Maecenas egestas arcu quis ligula mattis placerat. Vivamus consectetuer hendrerit lacus.

Praesent turpis. Vestibulum suscipit nulla quis orci. Aliquam erat volutpat. Integer tincidunt. Nunc interdum lacus sit amet orci.

Fusce risus nisl, viverra et, tempor et, pretium in, sapien. Pellentesque auctor neque nec urna. Nullam sagittis. Nulla neque dolor, sagittis eget, iaculis quis, molestie non, velit. Sed magna purus, fermentum eu, tincidunt eu, varius ut, felis.

General Questions

Vivamus laoreet. Cras id dui. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; In ac dui quis mi consectetuer lacinia. Aenean leo ligula, porttitor eu, consequat vitae, eleifend ac, enim. Etiam sollicitudin, ipsum eu pulvinar rutrum, tellus ipsum laoreet sapien, quis venenatis ante odio sit amet eros.

Praesent adipiscing. Pellentesque ut neque. Pellentesque libero tortor, tincidunt et, tincidunt eget, semper nec, quam. Sed hendrerit. Nullam accumsan lorem in dui.

Nam commodo suscipit quam. Etiam vitae tortor. Maecenas ullamcorper, dui et placerat feugiat, eros pede varius nisi, condimentum viverra felis nunc et lorem. Cras dapibus. Duis vel nibh at velit scelerisque suscipit.

Donec vitae orci sed dolor rutrum auctor. Nam adipiscing. Nunc egestas, augue at pellentesque laoreet, felis eros vehicula leo, at malesuada velit leo quis pede. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos hymenaeos. Suspendisse faucibus, nunc et pellentesque egestas, lacus ante convallis tellus, vitae iaculis lacus elit id tortor.

Fusce vel dui. Praesent congue erat at massa. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Fusce id purus. Cras dapibus. Ut varius tincidunt libero.

Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos hymenaeos. Aenean massa. Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Nullam cursus lacinia erat. Integer ante arcu, accumsan a, consectetuer eget, posuere ut, mauris.

Mauris sollicitudin fermentum libero. Curabitur ullamcorper ultricies nisi. Curabitur ligula sapien, tincidunt non, euismod vitae, posuere imperdiet, leo. Nam quam nunc, blandit vel, luctus pulvinar, hendrerit id, lorem. Praesent congue erat at massa.

Phasellus consectetuer vestibulum elit. Praesent blandit laoreet nibh. Pellentesque posuere. Aenean massa. Pellentesque commodo eros a enim.

Phasellus leo dolor, tempus non, auctor et, hendrerit quis, nisi. In ut quam vitae odio lacinia tincidunt. Cras dapibus. Phasellus a est. Aenean imperdiet.

Have another question? Get in touch with us and we'll get you sorted.