Screw this cold!

Forums › Home Workshop DIY › Screw this cold!

1 | 2 | 3

1039 posts

Uber Geek

#831396 6-Jun-2013 00:09

It's more expensive but I think it's worth it as doesn't lose it's R value over time and is what every new build in Europe uses (or similar like Kingspan)

New Zealand does suffer from a Luddite mentality when it comes to building where what's been done for years is 'right' even when things have moved on.

gazbo

89 posts

Master Geek

#831409 6-Jun-2013 04:34

R2.2 Pink Batts is likely the cheapest and easiest.

I don't think you can get any higher out of the known materials considering the 90mm you have to play with. You could actually batten off another 50mm on the inside of the studs to get a thicker wall depth seeing as you have the gib off, but you'll lose 50mm x wall length of floor area.

I don't know enough about Celotex to comment. I tend not to be an early adopter with construction materials because of the lack of testing to NZ conditions and the relative cost of failure being high.

Foam spray type products - The foam shrinks back from the framing upon drying leaving many heat escape paths. I would not consider them at all.

Niel

3267 posts

Uber Geek

Trusted

#831413 6-Jun-2013 06:20

The other issue with Airfoam is they assume the whole cavity is filled, but it is usually not especially in the corners.

Bradford Gold is good stuff and you don't need a mask/gloves. Pink batts are slightly better but not nice to work with.

If the walls are stripped then I'd go for polystyrene and seal around the perimeter. If the normal insulation size is not suitable for you, you can buy custom sizes direct from Expol. The concertina edge is so you do not have to seal it up (i.e. fast easy install), but solid polystyrene cut to size and sealed is much better.

With all insulation it is the edges that cause leakage. When you put your gib up, seal around the corners before you put the cove up. Initially the gib might seal, but over time gaps form and lets in cold. Just a little bit, but it is along a very long edge where you also do not have ceiling insulation.

You can never have enough Volvos!

wallop

367 posts

Ultimate Geek

#831423 6-Jun-2013 07:41

Remember with polystyrene you cannot have your electrical cables touching it.

timmmay

20591 posts

Uber Geek

Trusted

Lifetime subscriber

#831433 6-Jun-2013 08:05

mattwnz:
timmmay: Airform can shrink - it did a little inside my walls after a few years. I'd put in the thickest pink batts that fit, personally.

Yes I read about that. I had a quote for it to be done on two walls in my house and it was too high for me. Although I have seen a house done with it, and the results looked quite good. Not sure of the R value, but I can't see it being as high as fibreglass or wool. I think if you can, you get better results removing the gib and installing it. You can get R Values of 2.8 with 90mm fibreglass batts. ALthough you can get an R-value of 3.15 if you use Polystyrene XPS 90mm . http://www.designnavigator.co.nz/CRC.php

As I redo the gib I do replace it with pink batts. I'll look at that Cellostuff.

Airform missed parts of my walls. It wasn't arranged regularly, it's a super old house, so when taking the gib off we usually find a bit that wasn't insulated properly. Also drilling the holes in the outside was a bit of a nightmare, the wood was super oily and it leaked oil for months. Basically had to repaint the house, and you can still see where the holes are even after careful filling. I think I'm going to reclad because the paint won't stick to the house reliably anyway.

wallop: Remember with polystyrene you cannot have your electrical cables touching it.

My cables have the airfoam all around them.

wallop

367 posts

Ultimate Geek

#831434 6-Jun-2013 08:11

Maybe airfoam is a different chemical mixture compared to Expol? All the Expol bags I have used have a warning on the them about not touching cables. From what I was told the polystyrene reacts with the cables insulation eventually causing them to short out. You can wrap the cables to protect them. From the Expol website -

"For cables that come into DIRECT contact with Expol Underfloor, place Expol Wireguard around the wires before installation.".

DarthKermit

5346 posts

Uber Geek

Trusted

#831548 6-Jun-2013 12:36

^^^

Thanks for the comments guys. I decided to rip all the gib off to do a through job and also I wanted to install a few conduits for Ethernet and a couple of extra power points in the future.

There are a few large gaps that I want to block up. I'll post a pic later on.

Our house is an early 1950s build with stucco cladding. All the studs are rough sawn rimu 100 mm deep, so plenty of room for relatively thick insulation.

Whatifthespacekeyhadneverbeeninvented?

Quic Broadband

Move to New Zealand's best fibre broadband service (affiliate link). Free setup code: R587125ERQ6VE. Note that to use Quic Broadband you must be comfortable with configuring your own router.

timmmay

20591 posts

Uber Geek

Trusted

Lifetime subscriber

#831552 6-Jun-2013 12:49

I had half my bedroom re-jibbed when a new wardrobe system was put in. I had 5 new double power points put in, taking the bedroom total up to 8. We use about half of them too.

DarthKermit

5346 posts

Uber Geek

Trusted

#831643 6-Jun-2013 14:52

timmmay: I had half my bedroom re-jibbed when a new wardrobe system was put in. I had 5 new double power points put in, taking the bedroom total up to 8. We use about half of them too.

Eight! Are they all double outlets? I was thinking I'd like two * doubles in the spare bedroom, plus 2 ethernet outlets of 2 or 3 ports each.

Whatifthespacekeyhadneverbeeninvented?

DarthKermit

5346 posts

Uber Geek

Trusted

#831648 6-Jun-2013 15:02

Here's a peek inside my wall:

There's a large gap at the top by the soffit, which I intend to block up.

Whatifthespacekeyhadneverbeeninvented?

timmmay

20591 posts

Uber Geek

Trusted

Lifetime subscriber

#831649 6-Jun-2013 15:03

DarthKermit:
timmmay: I had half my bedroom re-jibbed when a new wardrobe system was put in. I had 5 new double power points put in, taking the bedroom total up to 8. We use about half of them too.

Eight! Are they all double outlets? I was thinking I'd like two * doubles in the spare bedroom, plus 2 ethernet outlets of 2 or 3 ports each.

Yes:
- Doubles each side of the bed (lamps)
- Double by the door (chargers)
- Double outside the full wall wardrobes each side (2). Being used for heater
- Doubles inside left, right, and center (not used, but for stereos, hair drier, etc)

Costs very little to install when the wall is open.

mattwnz

20177 posts

Uber Geek

#831654 6-Jun-2013 15:22

timmmay:
As I redo the gib I do replace it with pink batts. I'll look at that Cellostuff.
.

Apparently this stuff http://www.kingspaninsulation.co.nz/ has an R value of over 4 in a 90mm thickness, which is a lot better than others. But I am guessing it is expensive.

stuzzo

534 posts

Ultimate Geek

#831731 6-Jun-2013 17:18

Observing the way the horizontal timbers are nailed against the studs and the stucco placed on the wire frame I would be inclined to leave a gap the size of the horizontal timbers. This will allow adequate drying of the stucco if it gets wet ie just put insulation inside the studs.

Solid insulation should hold it's shape if cut correctly but if you are using fibreglass I'd staple cut strips of building paper at the back edge of the studs, folded at the edge so you can staple.

YadaMe

110 posts

Master Geek

#832096 7-Jun-2013 10:23

Christchurch gives and exeption for installing insulation into external walls, so other councils might too
http://resources.ccc.govt.nz/files/B390ExemptionInformationSheet.pdf

Just do it properly, you don't want it to pick up moisture from the external wall.

langers1972

1039 posts

Uber Geek

#832113 7-Jun-2013 10:32

mattwnz:
timmmay:
As I redo the gib I do replace it with pink batts. I'll look at that Cellostuff.
.

Apparently this stuff http://www.kingspaninsulation.co.nz/ has an R value of over 4 in a 90mm thickness, which is a lot better than others. But I am guessing it is expensive.

Yes because it's imported by Forman who also happen to own Pink Batts so, as usual, Kiwis are forced to use an inferior product as a big player controls the market. This stuff is as common as a cold in Europe but over here it's being artificially priced out of the market which is a shame as it's by far and away superior to glass fibre.

1 | 2 | 3