bubble foil insulation with kingspan board insulation advice

[pablom83]

Hi,

I'm adding an insulation at the first floor of my house which is made of timber and surround by roof tiles. It doesn't have an insulation at all right now and I'm wondering if it's worth adding the bubble foil insulation between kingspan 150mm and plasterboard.

Wall sections:
1. external roof tiles
2. breathable gap from the cold side
3. kingspan foil insulation between the rafters - first layer of kingspan boards
4. kingspan foil insulation - second layer of the kingspand boards
5. aluminium bubble foil insulation
6. battening - breathable gap, DO I NEED THIS GAP HERE?
7. vapour plasterboard - should I use non vapour instead if aluminium foil insulation is used?
8. gypsum

I'm wondering if anyone would have an idea of:
- If I should have the battening between aluminium bubble foil insulation?
- If I use the aluminium bubble foil insulation, should I then still use the vapour plasterboard?

Thanks in advance

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• pablom83
• 20 Mar 2015
• 1

This house is cornish unit type house, roof tiles cover first floor walls, which are made of...

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• pablom83
• 20 Mar 2015
• 1

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• pablom83
• 20 Mar 2015
• 1

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• pablom83
• 20 Mar 2015
• 1

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• pablom83
• 20 Mar 2015
• 1

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• pablom83
• 20 Mar 2015
• 1

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• pablom83
• 20 Mar 2015
• 1

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• pablom83
• 20 Mar 2015
• 1

 

[freddiemercurystwin]

I'm adding an insulation at the first floor of my house which is made of timber and surround by roof tiles. It doesn't have an insulation at all right now

Eh????

 

[pablom83]

Hi,

I've uploaded images of this house with some work I've done so far to make it easier to understand:
//www.diynot.com/network/pablom83/albums/24414

Yes, initially I was pretty confused with this too!

Thanks

 

[freddiemercurystwin]

 

[pablom83]

Thanks freddymercurystwin.

So after successfully adding these photos I'm still wondering if anyone has any good advice on my query.

 

[tony1851]

You're over-complicating it. Just put 2" kingspan between the uprights, flush with the room side; add 1" kingspan across the uprights, to avoid any cold bridging, then apply a foil-backed plasterboard and skim: job done.

Don't waste time and money faffing about with the rolled-foil products - they are little better than kitchen foil.

(BTW, are those ex-local authority 'Cornish' houses, by chance?)

 

[freddiemercurystwin]

Aye, like what tony said.

 

[pablom83]

Thanks Tony for an advice. Yes, I've been wondering if it's worth adding any aluminium bubble foil, but looks like it it's not. It meant to increase the overall insulation, because it's very thin and I've read pretty good comments about it.

Yes, you're right and this is ex-local authority 'Cornish' house. I'm really unimpressed that this house doesn't have any insulation at the first floor at all.

And after replacing all my windows and saving some money I will start adding this insulation to external walls in every room too.

 

[tony1851]

It meant to increase the overall insulation, because it's very thin

.......... that's the clue to its' rubbish performance - 'it's very thin'.

It depends for its insulation almost entirely on reflecting radiant heat, so to be at all effective, it has to have an air gap both sides.

You would achieve pretty much the same insulation value by using kitchen foil, and taping the joints - at a fraction of the cost.

 

[pablom83]

It meant to increase the overall insulation, because it's very thin

.......... that's the clue to its' rubbish performance - 'it's very thin'.

It depends for its insulation almost entirely on reflecting radiant heat, so to be at all effective, it has to have an air gap both sides.

You would achieve pretty much the same insulation value by using kitchen foil, and taping the joints - at a fraction of the cost.

Thanks Tony, unfortunately that's what I was worried about, but needed to check with others. I'll continue without buying the aluminium bubble insulation.