Ceiling/roof insulation "stay cool"

[xtrnuno41]

It is all wrapped in aluminium foil(?), guess it should be just one site.

Reflecting site to roof, fitted on the roof.

If the foil gets hot on one side, it will conduct the heat (as it is all wrapped around)to the other site, as alu is a warmth conducting. Then you still have a problem.

[Chazar]

53 minutes ago, CharlieH said:

Nice Job !! But the last image, it would seem the insulation you used is 4 inch (100mm) so your comment above regarding "over 2 inches" is off. (just saying ).????

I said I wasnt sure if 2-4  inch as its been 5  years since I was oop there.

[Lacessit]

3 hours ago, bankruatsteve said:

It's not clear to me what you have now and what you might be planning.  If you currently have a reflective radiant barrier under your roof then additional insulation above the ceiling is, IMO, superfluous. 

I would be interested in your engineering or scientific qualifications, or experience in the insulation industry, because IMO what you are posting is utter rubbish.

Before you ask, I was Chief Chemist of ACI Fibreglass in Dandenong, Australia.

[bankruatsteve]

3 minutes ago, Lacessit said:

I would be interested in your engineering or scientific qualifications, or experience in the insulation industry, because IMO what you are posting is utter rubbish.

Before you ask, I was Chief Chemist of ACI Fibreglass in Dandenong, Australia.

I have a BS Chem and a life-time of DIY experience. Perhaps you could point out which of my posts you unkindly claim are "rubbish" and let me respond. 

[CharlieH]

Gentleman, you may agree to differ, but you cannot start throwing accusations or insults.

 

7) You will respect fellow members and post in a civil manner. No personal attacks, hateful or insulting towards other members, (flaming) Stalking of members on either the forum or via PM will not be allowed.

 

Keep it civil please

[Lacessit]

13 minutes ago, bankruatsteve said:

I have a BS Chem and a life-time of DIY experience. Perhaps you could point out which of my posts you unkindly claim are "rubbish" and let me respond. 

All of them. You are claiming in order to reduce heat transfer into a living space, all that is needed is reflective foil. Which only works with direct radiation such as sunlight. The mechanism of heat transfer is convection in a roof space, NOT radiation.

If what you say was true, no-one would need brick or timber walls on a house, just reflective foil on a supporting frame.

[Lacessit]

3 hours ago, sometimewoodworker said:

As long as you don't try to cheep out you are wrong. The PU foam is self extinguishing due to the fire retardants incorporated. The wiring should not be attached to the roof but on the walls or ceiling so will net be encapsulated by the PU foam.

 

I have some pieces of the foam and it's impossible to get them to burn without a constant flame on them, even the thinnest, and even then they don't burn at all well.

I think we've had this argument before. IMO you are missing the point. It's not about whether the PU will burn with or without flame retardants. It's about what is generated when a source of heat is applied to the PU, and what it will do in an enclosed environment.

Try breathing the stuff that's emitted when you apply a flame to it, and I think you'll understand what I mean. Do it carefully.

[Lacessit]

47 minutes ago, CharlieH said:

Gentleman, you may agree to differ, but you cannot start throwing accusations or insults.

 

7) You will respect fellow members and post in a civil manner. No personal attacks, hateful or insulting towards other members, (flaming) Stalking of members on either the forum or via PM will not be allowed.

 

Keep it civil please

My apologies to you and Steve. I do get cantankerous with posts I believe are plain wrong. I can't even use the excuse I had not taken my meds today.

[Thainesss]

44 minutes ago, Lacessit said:

All of them. You are claiming in order to reduce heat transfer into a living space, all that is needed is reflective foil. Which only works with direct radiation such as sunlight. The mechanism of heat transfer is convection in a roof space, NOT radiation.

If what you say was true, no-one would need brick or timber walls on a house, just reflective foil on a supporting frame.

 

This is correct. 

 

Air conditioning systems are designed to use convection to their advantage as well. They make use of heat rising and pull the warm air from near the ceiling and cool it (pulling humidity) and blow that same dried cool air into the room over and over again. 

 

If your ceiling is constantly warmer (or hot-as-balls) than your target temp - the system has to work harder and thus more BTU’s are needed and more electrical power. 

 

Insulation works. 

[bankruatsteve]

37 minutes ago, Lacessit said:

All of them. You are claiming in order to reduce heat transfer into a living space, all that is needed is reflective foil. Which only works with direct radiation such as sunlight. The mechanism of heat transfer is convection in a roof space, NOT radiation.

If what you say was true, no-one would need brick or timber walls on a house, just reflective foil on a supporting frame.

No. What I said is that reflective foil is the best way to reduce heat transfer in tropical climate. BTW all heat is radiated. Not just from the sun. My point has been that additional insulation is superfluous. If you don't agree, then give your qualified reason for that. 

[sometimewoodworker]

39 minutes ago, Lacessit said:

4 hours ago, sometimewoodworker said:

As long as you don't try to cheep out you are wrong. The PU foam is self extinguishing due to the fire retardants incorporated. The wiring should not be attached to the roof but on the walls or ceiling so will net be encapsulated by the PU foam.

 

I have some pieces of the foam and it's impossible to get them to burn without a constant flame on them, even the thinnest, and even then they don't burn at all well.

I think we've had this argument before. IMO you are missing the point. It's not about whether the PU will burn with or without flame retardants. It's about what is generated when a source of heat is applied to the PU, and what it will do in an enclosed environment.

Try breathing the stuff that's emitted when you apply a flame to it, and I think you'll understand what I mean. Do it carefully.

That is not what you said. You implied that an electrical short could easily start a fire in the PU foam. It can not

 

Exactly what you said was 

Quote

If there is a short in any of the wiring running through the ceiling, it's a major fire hazard.

The PU foam can create bad stuff if it is subjected to fire but it isn't something that will make fire more likely.

 

To get your message across you need to be careful that you don't "Trumpify" it or it will just be regarded as Fake News.

[Lacessit]

2 minutes ago, bankruatsteve said:

No. What I said is that reflective foil is the best way to reduce heat transfer in tropical climate. BTW all heat is radiated. Not just from the sun. My point has been that additional insulation is superfluous. If you don't agree, then give your qualified reason for that. 

The three mechanisms of heat transfer are radiation, convection and conduction. On a roof surface, reflection is obviously best. There is no radiation inside the space between a roof and the internal ceiling, it is all convection. I think we can exclude conduction unless we want to start debating how much metal foil contributes.

Insulation is a multi-billion dollar industry world-wide. Do you really think that industry could survive if it was superfluous?

 

[Lacessit]

17 minutes ago, sometimewoodworker said:

That is not what you said. You implied that an electrical short could easily start a fire in the PU foam. It can not

 

Exactly what you said was 

The PU foam can create bad stuff if it is subjected to fire but it isn't something that will make fire more likely.

 

To get your message across you need to be careful that you don't "Trumpify" it or it will just be regarded as Fake News.

I don't think there's any point in continuing this. You have your opinion, I have mine.

[bankruatsteve]

I think insulation is great - unless it is superfluous.  OK end. It would be nice if a PhD in thermodynamics could 'splain this. ????

[Lacessit]

43 minutes ago, bankruatsteve said:

I think insulation is great - unless it is superfluous.  OK end. It would be nice if a PhD in thermodynamics could 'splain this. ????

I've explained it to you. I can't understand it for you.

[CharlieH]

Off topic removed (again)

[xtrnuno41]

1 hour ago, Lacessit said:

I don't think there's any point in continuing this. You have your opinion, I have mine.

EPS/XPS very very flammable can drip and spread fire, the white foam for packing.

EPS-SE, PUR, very flammable and contribute to fire, PIR less to ignite but as easy to burn as PUR. 

PIR with glass fibre and PF hard flammable. PF ignites at 400 Celsius

Mineral products MWG, MWR, CG practical un flammable.

 

So all depends on what foam you have and you better have best, mineral products (NO foam). Stone , glass wool.

An electrical shortcut with wiring in the foam can have a fire started, again depending on which foam you use it starts right away or some later.

I guess they will still develop on and on and maybe now there are even more foams in a better way.

[Old Croc]

15 hours ago, Lacessit said:

The mechanism of heat transfer is convection in a roof space, NOT radiation.

Thanks for that. I don't have any qualifications in the field and it seems I used the wrong term in an earlier post.

 

[fredge45]

On 6/30/2019 at 8:45 PM, Thainesss said:

Every time I see threads like this I’m always shocked at people questioning the need or “point” of insulation. 

 

First of all, in a basic Thai house with a tile roof and gyprock ceiling - attic temps get up over 60C. I’ve put a sensor up there in mine to check it. 

 

Second, insulation will block most of that heat from radiating downward into your room. 

 

Third, if you use aircon, then it also creates a barrier and keeps the cool air in the room. The aircon doesn’t have to battle the heat radiating down from your attic space - requiring much less BTU’s to cool a space. 

 

Spending 20-30k to put insulation in your roof is beneficial even if you don’t use aircon, and even more beneficial if you do. 

 

 

Critical point in reducing the convection of heat from the ceiling, in addition to a minimum of 15 cm of fiberglass insulation of the highest R-value available, is to ventilate the attic space.  Reducing the temperature in the space will increase to efficiency of the installed insulation dramatically.

 

[spidermike007]

18 hours ago, Chazar said:

your  wish, do everything myself, no problems EVER.

Anyone who thinks insulation does nothing is  nuts, this  building 50m2 double  block wall with air gap between walls, roof insulated with two inch maybe 4  inch thick cant remember now one 9000 btu keeps it  cool even in 40+c  heat, bills with it on permanently 1000bht cool season 1600 hot  season, set at 26c forever ie 24/7 windows doors  sealed air  tight.

Is that the correct way to install the batting? Lay them over the 2 x 4's? Instead of running them in between them? 

[Thainesss]

16 minutes ago, spidermike007 said:

Is that the correct way to install the batting? Lay them over the 2 x 4's? Instead of running them in between them? 

 

I don’t think there’s any 2X4’s in those pics. 

[spidermike007]

1 minute ago, Thainesss said:

 

I don’t think there’s any 2X4’s in those pics. 

Well, this looks like a suspended ceiling. In most houses, where there is a solid ceiling, I would imagine there are beams or 2 x 4's, to support the ceiling structure, correct? In that case, could you lay the batting over the wood struts, or in between them? 

[Denim]

1 minute ago, spidermike007 said:

Well, this looks like a suspended ceiling. In most houses, where there is a solid ceiling, I would imagine there are beams or 2 x 4's, to support the ceiling structure, correct? In that case, could you lay the batting over the wood struts, or in between them? 

 

Those are not 2x4's

 

On the end of the vertical aluminium strips coming from the roof are fastened horizontal strips which run across the room and are anchored on the walls. The plasterboard ceiling is then attached to the aluminium frame. You can lay the insulation any way you find convenient.

When building our house I had them weld a steel gantry the whole length of the attic so as to give me safe access to all points since aluminium framework will not hold the weight of a human.

[CharlieH]

7 minutes ago, spidermike007 said:

Well, this looks like a suspended ceiling. In most houses, where there is a solid ceiling, I would imagine there are beams or 2 x 4's, to support the ceiling structure, correct? In that case, could you lay the batting over the wood struts, or in between them? 

I think that conventional "western style" have the beams at 600 centres and that relates directly to the product being made at 600 wide so that it would roll out between the beams.

The general method (as I understand it) here in Thailand is the "suspended" system with aluminium hangers etc as can be seen in the above pic and nicely described by poster Denim.

[GarryP]

11 minutes ago, Denim said:

 

Those are not 2x4's

 

On the end of the vertical aluminium strips coming from the roof are fastened horizontal strips which run across the room and are anchored on the walls. The plasterboard ceiling is then attached to the aluminium frame. You can lay the insulation any way you find convenient.

When building our house I had them weld a steel gantry the whole length of the attic so as to give me safe access to all points since aluminium framework will not hold the weight of a human.

The suspended ceiling is a concern of mine. I would prefer something stronger so it would be easier to make repairs, lay insulation, etc. Trying to get a dying pigeon off my ceiling was a pain as it was so far from the surrounding wall tops. In the end I had to use an extendable landing net to get the flying rat. Would have been so much easier with a steel frame or western style beams. 

Edited July 2, 2019 by GarryP

[Thainesss]

11 minutes ago, spidermike007 said:

In that case, could you lay the batting over the wood struts, or in between them? 

 

If it were 2X4’s in the western sense then they go between them. 

 

In the suspended ceiling they go between the ceiling supports in any fashion you can fit them, as close to the gyprock as you can get it. 

[Thainesss]

1 minute ago, GarryP said:

The suspended ceiling is a concern of mine. I would prefer something stronger so it would be easier to make repairs, lay insulation, etc. Trying to get a dying pigeon off my ceiling was a pain as it was so far from the surround wall tops. In the end I had to use an extendable landing net to get the flying rat. Would have been so much easier with a steel frame or western style beams. 

 

You can do that if you wanna pay for it. 

 

But suspended ceilings are more then strong enough to support insulation, and strong enough to support a ceiling fan if you put a doubler/backing brace across a few supports. 

[GarryP]

18 minutes ago, Thainesss said:

 

You can do that if you wanna pay for it. 

 

But suspended ceilings are more then strong enough to support insulation, and strong enough to support a ceiling fan if you put a doubler/backing brace across a few supports. 

I understand that they are strong enough to support the gadgets. It's just that they are not strong enough to support me. 

 

Wonder how much the steel frame would run to? 

Edited July 2, 2019 by GarryP

[Denim]

13 minutes ago, GarryP said:

The suspended ceiling is a concern of mine. I would prefer something stronger so it would be easier to make repairs, lay insulation, etc. Trying to get a dying pigeon off my ceiling was a pain as it was so far from the surround wall tops. In the end I had to use an extendable landing net to get the flying rat. Would have been so much easier with a steel frame or western style beams. 

 

This depends on whether you are buying a new build house or are having your own built. If you are buying a built house then you will get some kind of suspended ceiling. If you are having your house built it is up to you what kind of ceiling you want.

You can have a 2x4 steel frame but of course it will be more expensive and heavier

 

As I said, I had a steel gantry welded down the center of the attic to give me access. well worth the little extra.

 

 

Edited July 2, 2019 by Denim

[CharlieH]

Just now, GarryP said:

I understand that they are strong enough to support the gadgets. It's just that they are not strong enough to support me. 

 

Wonder how mush the steel frame would run to? 

You could consider using running boards, get some planks strategically placed between the steel roof frame (assuming you have the height).

 

Just a suggestion. I did that and it worked out well when laying the insulation.