Thai insulation rating @ Renovation fair

[the-monk]

Thai insulation rating.

I plan to install insulation mats ( fiberglass or ?? ) directly on the room suspended ceiling.
At present no insulation exists between the suspended ceiling and the uninsulated roof.
I am not familiar with the Thai insulation rating system. As shown on the pics
below it goes from a Rt 27 for a 3 inch thick mat to a Rt 37 for a 6 inch one.
Can anyone explain the Rt 27 and Rt 37 ? How to compare with western standards ?

It seems that all major construction material retailers ( Home, Global etc ) sell fiberglass
insulation. In the past, before coming to Thailand, i have used fiberglass insulation
and i was pleased with the results. Other possible options ?

Suggestions and comments are most welcome.
Thanks to all.
Have a pleasant day/evening.


N.B There will be an ISAN RENOVATION FAIR at Central Plaza Sunday

[waanjai]

Rt27 or Rt37 seem to be the old "R = Thermal Resistance R" but called Resistance t - t for thermal.
The higher the value of R, the better a certain material insulates against thermal changes - in Thailand this will predominantly be "heat".
Though of course any wall, ceiling or roof insulation will also prevent cold air to enter a house thru the protected areas in the tropics. (December/January).

P.S.
The fair starts tomorrow.

[waanjai]

The people who produce special concrete blocks - autoclaved aerated concrete block (Q-Con or Superblock) - with the aim of as much thermal insulation as possible call it: Thermal Resistivity, R.

E.g. have a look at the R-values of Q-Con aerated concrete blocks depending on the thickness of the blocks:

The R-values are much higher than those of fiberglass matts, reflecting the fact they are for outside walls.
Nevertheless, the very often used concrete blocks by Thais with thickness of only 7.5 cm are at the lower end of the possibilities and might reflect their cheap charly buying behaviour.

Many Farangs nowadays tend to use the 20+ cm thick blocks because of the much higher thermal resistivity.

[Barney]

The-Monk

I just recently insulated my new house, roof and walls with the attached photo type of insulation.
About 170bht per roll from Do Home. Discount was applied as I bought over 200 bags.
Has a good general rating of R-21 and was far cheaper than some of the other higher R rated brands.
You can see the size 600mm wide x 4000mm long giving 2.4 mtrs coverage per bag.

It is covered in the foil to stop fibres floating. Buy some of the silver tape available and tape the foil pillow closed if you cut the bag to size for smaller spots. You don't want fibres in the air. If you cut then wear safety gear , goggles, long sleeve clothes. Be careful when laying near your electrics. Down lights extending into the ceiling space may need to be considered for heat build up. Give them some room when placing.

[PhenMan]

I strongly suggest that you never use any kind of foil over your rafters. This is extremely dangerous as it is a conductive material and typically you have electrical cable running across your rafters. IMHO foil should only be used as a lining under your roofing material and only non-conductive material used in and around rafters...

Just saying.

[the-monk]

OK This makes sense to me, especially here in Thailand, where taped connections are spliced from other cables over the ceiling without any boxes. Any suggestion as to what should be used over a suspended ceiling to provide the best posible insulation factor. This is an old Thai style house.

[noosard]

Pity the Australian government's insulation scheme didn't take advice about this problem
Their rush to implement cost lives and houses
and then money to remove all the foil placed on ceilings