Ceiling Insulation (foil type)

[Kwasaki]

1 hour ago, Denim said:

builders sometimes put a thin strip of polystyrene in the middle of a poured cement floor to act as en expansion gap.

 Polystyrene blocks are also used in construction for walls, floors and roof. ? 

[sometimewoodworker]

On 7/9/2018 at 6:23 AM, 4MyEgo said:

http://www.polynum-insulation.com/index.php?page_id=36 

Cost 60,000 baht to cover 230m2

 

 

We have gyprock sheets 2400 x 1200 if memory serves me correctly, no squares. 

 

I think we will disconnect the LED downlights, however leave them in the ceiling, and put the large LED lights, one per room in the middle, so that we can cover all ceiling areas as opposed to leaving gaps, otherwise there will be a few gaps, and I want it to be as effective as it can be.

 

 

The insulation that you selected "Polynum^TM" seems to be extremely  expensive however as long as you have a shiny side facing into your roof it should do a reasonable or good job.

 

The ceiling you have will be OK. I wouldn't bother to disconnect the LED downlighting, just put something like mesh over the top of them to keep an air space between them and the insulation.

[sometimewoodworker]

22 hours ago, 4MyEgo said:

Good advice, and no arguments here.

 

We have no cement around the house, except the front for the driveway, sides walls do not get direct sunlight on them, (covered by awnings), mostly blue metal/stone, or grass runs along the side of the house.

 

Going out shortly to check out the batts, their ratings and price, the area I have is about 300m2, so will more than likely be in the vicinity of about 60,000-90,000 baht installed, I would imagine, that said, I am good at squeezing blood out of a stone, so will see what we can come up with.

That would be an unreasonable price, unless you want an extremely thick double or triple layer. I would put it at 20,000 to 50,000 max

[4MyEgo]

42 minutes ago, sometimewoodworker said:

The insulation that you selected "Polynum^TM" seems to be extremely  expensive however as long as you have a shiny side facing into your roof it should do a reasonable or good job.

 

The ceiling you have will be OK. I wouldn't bother to disconnect the LED downlighting, just put something like mesh over the top of them to keep an air space between them and the insulation.

The thermal reflective insulation is the best on the market in Thailand, having carried out extensive research and reviews, it is 3cm wide on each side, therefore reducing the time that it takes the heat from penetrating into the attic, I thought the price was reasonable considering the effect.

 

Placing mesh over the top the LED, here is an interesting link to read, and as I said previously, I will leave them in place, but they will be disconnected, i.e. I will place ceiling (LED) lights to the exterior of the ceiling, i.e. not recessed so as to eliminate any potential hazards, safer than sorry and cheap enough to do here in Thailand, I am not on any budget. 

 

https://lumitex.com.au/can-i-cover-led-downlights-with-insulation/

 

I appreciate your input, thank you.

Edited July 10, 2018 by 4MyEgo

[4MyEgo]

10 minutes ago, sometimewoodworker said:

That would be an unreasonable price, unless you want an extremely thick double or triple layer. I would put it at 20,000 to 50,000 max

Naturally I will be going for the highest R rating so as to reduce the time it takes for the heat in the attic to enter the house through the ceiling, i.e. similar rating to the thermal reflective insulation.

 

I have worked long enough to save my coins, to have a comfortable life, but not going over the top, 60,000-90,000 baht again sounds reasonable for the effect, however I have not priced the ceiling insulation batts yet, but will be breaking some balls to get the price down, after all, we all want the best price, but also the best product available for the job, and the investment over the length of time ones uses it, pays dividends in comfort, in my opinion.

[sometimewoodworker]

7 hours ago, 4MyEgo said:

The thermal reflective insulation is the best on the market 

The primary way that the foil works is as a poor radiator of heat from the shiny side that is facing down into the roof space. Any reflective property is of minimal importance.

 

I have a documented thread on a site that is dedicated to cool buildings in Thailand  I have a measured 61 degrees C from the underside if the un insulated blue roof, with the cheapest foil it is 37 degrees C or basically ambient air temperature 

 

 

To test this get a frying pan nice and hot then see how close to the hot surface you can put your hand. Then put a large piece (one that covers all the base) of kitchen foil in the pan shiny side up and try again. The first one you will have to keep your hand 10cm or 15cm away 2nd case may be 1cm or 2cm.

[4MyEgo]

1 hour ago, sometimewoodworker said:

The primary way that the foil works is as a poor radiator of heat from the shiny side that is facing down into the roof space. Any reflective property is of minimal importance.

 

I have a documented thread on a site that is dedicated to cool buildings in Thailand  I have a measured 61 degrees C from the underside if the un insulated blue roof, with the cheapest foil it is 37 degrees C or basically ambient air temperature 

 

 

To test this get a frying pan nice and hot then see how close to the hot surface you can put your hand. Then put a large piece (one that covers all the base) of kitchen foil in the pan shiny side up and try again. The first one you will have to keep your hand 10cm or 15cm away 2nd case may be 1cm or 2cm.

That is still a hot temperature for an attic space, looks to me like a flat roof and outside, so really shouldn't count.

 

I have tested the heat in the attic space with the gable roof we have, which you can stand up in most areas, the times varied and at the peak the hottest temperature in summer we got a reading of 30 degree Celsius which to me wasn't to bad considering it was around double that prior to the reflective thermal insulation, now 7 degrees can make a hell of a difference. 

 

That said, once the batts go in, that should effectively slow the heat transfer through the ceiling into the house, which usually heats up at around 2pm - 3pm, so I am confident the $'s or baht for that matter out laid for a superior product is as I mentioned earlier, money well spent and the addition $'s or baht to be spent on the batts will effectively give me what I want, a cooler house after 2pm - 3pm and into the evening, its not rocket science, however you also have to compare roofing material, attic space height, width, what vented air circulation you have in the attic and extractors to get the best possible results.

 

I believe I am on the right, thanks all the same.

Edited July 10, 2018 by 4MyEgo

[sometimewoodworker]

On 7/10/2018 at 6:56 PM, 4MyEgo said:

That is still a hot temperature for an attic space, looks to me like a flat roof and outside, so really shouldn't count.

Why should it not count?

It is a metal roof, the pitch is irrelevant, the fact that it is outside is again irrelevant.

 

The temperature drop is a documented 24 degrees C, using the cheapest possible foil 1,200 Baht for 70 metres. Total material cost about 400 Baht.

 

Will other methods work? Certainly, though on a heat reduction for cash input nothing comes remotely close.

 

Can you improve the results using foam on the back? Quite possibly 

 

Would you want to add insulation above the ceiling? We did, you may want to.

 

Should you use a radiant barrier on the underside of your roof? You would have to be stupid or have an unbelievably good reason not to have one.

 

Would venting the roof space be a good idea? Quite likely, we have clearstory opening windows at about 5 metres above our floors, they are not in current use as I haven't made mosquito screens yet, so I can't give a definitive comment. But even when the bottom level of our living room is at 28 degrees the top level is at least 29 to 30 and the ceiling fans at 3.8 metres don't affect that area.

 

Edited July 12, 2018 by sometimewoodworker

[4MyEgo]

On 7/7/2018 at 11:35 AM, Denim said:

Rolls of foil are available at most large hardware stores.

 

I bought some direct from the factory to save a bit of cash but later found some cheaper at Global.

 

Obviously , the thicker they are the more effective. However we initially went with the cheap 2 inch type and noticed a big difference. I then added another 2 inch layer on top.

 

They are easy to unroll if you have good access.

 

One observation is that they really slow down the build up of heat under the ceiling. However , in the evening, when It can be cool outside, the insulation retains the heat that has built up during the day.

 

To offset this  we have an large extractor fan in the kitchen ( open plan house design ) which we turn on for an hour around nightfall.

UPDATE:

 

I have done my research on costing and comparing some other products, now it appears SCG is the superior product available from what I have researched (call that marketing if you like), however was told by another hardware person who was trying to push MPE  and EE, that SCG is dangerous as it can catch fire and the material can cause cancer, perhaps this DH should go to SCG's website and see the video and accreditations that their product has.....lol

 

I am looking at going for the 150mm, or 6 inch R-37 SCG Stay Cool product, and the cost is 425 baht at HomePro per bag or 2.4m2 of which I will be only getting 222m2 now as a section of the house is sealed up there and we don't really use the other area of 64m2, so if that section gets hot, the whirlybirds will extract what heat is in the ceiling and we have a big sliding door which stays closed in that area, keeping it sealed from the house.

 

The cost to buy is 40,000 baht plus delivery, now before I go out and purchase it, all 93 bags, just want to see what anyone has to say about this product if they have it:

 

Is there another product as good with a similar R- rating that is cheaper, but also safe

 

How much of a difference will the heat be reduced, eg 3 degree or more

 

What should I pay to have it installed per square metre.

 

Should I have it taped where it joins or leave it.

 

All final comments are appreciated and welcomed.

Edited July 13, 2018 by 4MyEgo

[4MyEgo]

On 7/7/2018 at 1:19 PM, Denim said:

 

Agreed. Its like putting water in a saucepan. If the flame is high it boils quickly. If the flame is low, it still boils but takes that much longer to come up to heat.

 

Another option you can have ( which we don't ) is to have an extractor fan in your roof space that you can turn on 30 minutes before it gets dark to assist in sucking out the built up hot air.

 

Pretty cheap and every little helps.

 

 

You could try whirlybirds as I have, they do extract the heat from within the ceiling space, no breeze required, if you get the ones with good ball bearings as they freely spin all day

[Denim]

56 minutes ago, 4MyEgo said:

You could try whirlybirds as I have, they do extract the heat from within the ceiling space, no breeze required, if you get the ones with good ball bearings as they freely spin all day

 

Whirlybirds are ok if the pitch of your roof is not too steep. We had one over the kitchen at our last house.. Our new house has steep piched roof so can't have them. Also, they are not the most beautiful of things. OK if they are out of sight round the back but personally wouldn't want one visible out front.

[sometimewoodworker]

On 7/13/2018 at 6:06 PM, 4MyEgo said:

How much of a difference will the heat be reduced, eg 3 degree or more

How hot do the ceilings of the finished area get? How much hotter than the interior walls?

 

If both are the same temperature then your insulation may make virtually no difference. 

 

You should expect the insulated ceiling to be no different to the interior walls

 

 

On 7/13/2018 at 6:06 PM, 4MyEgo said:

Should I have it taped where it joins or leave it.

We didn't bother.