Spray Foam Insulation

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AACTech

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#159944 18-Dec-2014 05:42

Will be buying an old house in Napier soon and was wondering if any one has had experience with closed cell spay foam insulation.

Is there even any properly trained "Foam Masters" in New Zealand?

1 | 2 | 3

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#1199614 18-Dec-2014 06:16

I have it in my house, I'm not sure I'd do it again. Thoughts:
- They drill holes EVERYWHERE to insert the foam. Despite what they say ("we fill and prime, all you need to do is paint") you have to do a lot of work to smooth the wood, print, paint. It takes AGES and the result is still lots of circular holes in the house. I want to reclad, though not just because of this.
- My house framing is irregular (very old house, some additions) and they missed sections. I can see this when I take off wall linings.
- The foam shrinks a bit over time.
- There are reports that it isn't good re moisture
- I didn't notice much difference in winter warmth - though I did it in summer. When I did ceiling there was a huge immediate benefit, and again when I put another layer up there. I didn't get that with wall insulation. Underfloor didn't help much for warmth, given we have carpet and a lining, but it along with plastic under the house made a huge difference to moisture and smell in the house.

A few photos from when we relined a room - ours was done 3-5 years ago by airfoam Wellington or lower hutt.

JayADee

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#1199615 18-Dec-2014 06:24

Interesting photos.

AACTech

34 posts

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#1199647 18-Dec-2014 07:57

Timmay is it correct that you had the foam sprayed into the wall cavity through a series of holes?

Everything I have read says not to do this. They say remove interior lining on the external walls, spay and then reline.

Also was it open or closed cell polyurethane foam as the closed cell has no problem with moisure.

What did it cost, if you don't mind me asking?

timmmay

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#1199650 18-Dec-2014 08:10

Yes, through holes. It's MUCH MUCH quicker and easier than removing all your wall linings, insulating, putting up new linings, plastering, and painting. It cost about $3500 from memory. Don't know what kind of foam it is, the company has gone out of business - see a worrying warning letter here.

If you're opening up the walls go for a more standard product IMHO. Much lower risk. Though I'm pretty sure I wouldn't open up all my walls to do it, too expensive and disruptive.

AACTech

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#1199656 18-Dec-2014 08:25

Thing is NOT openning the walls, and you've unfortunately proved this, make the job next to useless.
From your photos I see many open spaces in the wall cavities. No wonder you noticed little difference during the cold weather. It is like leaving the door open.

timmmay

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#1199663 18-Dec-2014 08:42

It's not quite as bad as leaving a door open, the wood, internal linings, and air space has insulation properties, but yes it seriously compromises the effect of the insulation.

gzt

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#1199669 18-Dec-2014 09:01

From memory there are formaldehyde and non-formaldehyde.

Sharesies

Trade NZ and US shares and funds with Sharesies (affiliate link).

dolsen

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#1199675 18-Dec-2014 09:16

timmmay: see a worrying warning letter here.

Don't have access to your C:\ drive to see the letter...

And now it works. When I first looked it had a link to a c:\ drive, now it is going somewhere else...

AACTech

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#1199676 18-Dec-2014 09:19

Timmmay,

Thanks very much for your replies and especially the photos. You have been very helpful.
Will let you know how things go after we settle in Napier.

The price you paid sound very encouraging.

Sounds like the real problem is getting experienced, qualified, professional tradesmen to do the work.

timmmay

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#1199679 18-Dec-2014 09:29

dolsen:
timmmay: see a worrying warning letter here.

Don't have access to your C:\ drive to see the letter...

And now it works. When I first looked it had a link to a c:\ drive, now it is going somewhere else...

Yeah GZT told me, difficult to link to as Google linked directly to a PDF that started downloading. Rookie mistake though.

AACTech: Timmmay,

Thanks very much for your replies and especially the photos. You have been very helpful.
Will let you know how things go after we settle in Napier.

The price you paid sound very encouraging.

Sounds like the real problem is getting experienced, qualified, professional tradesmen to do the work.

Based on that link I posted I really strongly recommend you do your research properly if you're considering foam. There are many drawbacks and given you're removing wall linings no real advantage. Standard insulation isn't much more expensive from memory.

NZSpides

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#1199705 18-Dec-2014 09:50

The last house we owned we renovated the lounge/kitchen/dining room.
It had this wall insulation in the wall sprayed through the bricks from outside.

The job was well done, I didn't even know it had been done until the renovation had started.
However we relined the area with pink bats and the difference in heat loss was staggering!

After we did the renovation, the room was much warmer.
The foam when we removed it, had shrunk in its dimensions by at least 2cm in width and height, allowing effectively cold air to flow right up to the gib.

The foam also seemed to have dissolved the building paper as well.

If you really want insulation, I would NOT recommend the spray foam, its a short cut that is only marginally effective and doesn't seem to last that long.

mdf

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#1199714 18-Dec-2014 10:05

We looked at it when we were renovating our house. Our house is a 1900s cottage, so doesn't have dwangs (the horizontal pieces of timber between the vertical studs), rather sarking (essentially horizontal boards over the top of the studs). Because of this, they could have filled each section between the studs with just one hole - i.e. much cheaper and faster than the multiple holes dwangs require. In the end we decided to reline and use conventional bats. I read a number of reviews online, some of which were glowing, others not so much. Our house is built on clay so damp at the best of times, and there seemed to be some real issues about whether the stuff (1) gave off moisture as it dried and (2) retained moisture.

I also read one review where the installer hadn't properly sealed up all the internal power sockets. Apparently the guy commented that "he seemed to have used a lot of foam" but it was only later that the homeowner opened a wardrobe to find it full of the stuff because it had come through an open socket! :)

If you're seriously contemplating removing the internal lining, go with bats or one of its variants.