Ceiling/roof insulation
Yes, we all have those I think. My thinking was the foam hose is hooked up to some kind of tank truck. The hose has to be quite long and woven up through your windows/rooms and into the attic hatch. Much easier when the house is under construction and you can pull the entire truck almost into the house. Petenevets wrote:I would have thought an inspection hatch big enough for a person to go through when built would be essential. I have one in the ensuite to one of the bedrooms.
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- JimmyGreaves
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So is the idea of this the following:
1. The foil under the roof tiles reflects the sun off the roof thus keeping the roof space temperature down
2. The fibreglass that is to be laid on top of the plasterboard ceiling is there to hold any cold air in from aircon units?
I would have thought the fibreglass would also stop the heat rising and hold it in the room if the aircon was not being used, thus making it hotter. Also most roof spaces at least have some airflow space even if it is only where the bird/animal plastic stoppers go at the eaves
1. The foil under the roof tiles reflects the sun off the roof thus keeping the roof space temperature down
2. The fibreglass that is to be laid on top of the plasterboard ceiling is there to hold any cold air in from aircon units?
I would have thought the fibreglass would also stop the heat rising and hold it in the room if the aircon was not being used, thus making it hotter. Also most roof spaces at least have some airflow space even if it is only where the bird/animal plastic stoppers go at the eaves
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There is no simple answer, as there are too many variables involved. In a building in Thailand we are mostly concerned with "radiated" heat from the sun, as there are basically three types of heat transfer, radiation, convection and conduction.JimmyGreaves wrote:So is the idea of this the following:
1. The foil under the roof tiles reflects the sun off the roof thus keeping the roof space temperature down
2. The fibreglass that is to be laid on top of the plasterboard ceiling is there to hold any cold air in from aircon units?
I would have thought the fibreglass would also stop the heat rising and hold it in the room if the aircon was not being used, thus making it hotter. Also most roof spaces at least have some airflow space even if it is only where the bird/animal plastic stoppers go at the eaves
Most of this radiated heat enters through the roof, as that is the most exposed area to direct sunlight. The material used to construct the roof has a big bearing on how much heat, and what type of "heat transfer" takes place, some will be by conduction, but mostly by radiation transfer.
Some heat will come through the walls, but the amount will also be affected by the type of construction, exposure to direct sunlight, etc.
So, yes, the reflective foil under the tiles is a very good start, as it tends to deflect the direct radiation, but not all of it, and it also conducts to a certain degree, so some heat will pass through, which heats up the ceiling space.
The fibre laid on top of the plasterboard consists of a multitude of tiny air cells which block both radiation and conduction. And it works in both directions, therefore helping to retain the cooler air conditioned side as well as blocking the hot side. Bear in mind that heat always travels from a hotter part of any material to a cooler part, always!
There is a lot of good information on the Internet, but just remember that it is a complex subject, and therefore can be a bit daunting trying to establish a clear picture.
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- Khundon1975
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prcscct
I would imagine that for small houses, as opposed to larger commercial buildings, the equipment needed would be a lot smaller.
Maybe a small compact wheeled compressor, with shorter hoses etc.
The foam is made up of two low viscosity liquids, an isocyanate and a resin, which are mixed at the spray head. As this mixed foam expands to 30 times the volume and attains around 90% closed cell volume, then the amount of raw materials needed for a house would be small, a couple of 25 Lt drums would do the trick. No need for a huge lorry in the lounge.
We had may dads house done a few years ago and we opted for the maximum density blend, which gave a weight of 60Kg per M3.
Translated into a thickness of around 25mm M2 that would be about 2kg per M2, so the added weight to a roof would be negligible.
The only problem with a roof that has been fitted with a reflective foil, is that it may have to be removed, (they removed the felt sheeting in my dads roof) in order for the foam to stick to the underside of the tiles or cement sheeting. Not sure on that though.
I wonder if the Thai companies use CFC liquids now, as they would be virtually fume free.?
I would imagine that for small houses, as opposed to larger commercial buildings, the equipment needed would be a lot smaller.
Maybe a small compact wheeled compressor, with shorter hoses etc.
The foam is made up of two low viscosity liquids, an isocyanate and a resin, which are mixed at the spray head. As this mixed foam expands to 30 times the volume and attains around 90% closed cell volume, then the amount of raw materials needed for a house would be small, a couple of 25 Lt drums would do the trick. No need for a huge lorry in the lounge.
We had may dads house done a few years ago and we opted for the maximum density blend, which gave a weight of 60Kg per M3.
Translated into a thickness of around 25mm M2 that would be about 2kg per M2, so the added weight to a roof would be negligible.
The only problem with a roof that has been fitted with a reflective foil, is that it may have to be removed, (they removed the felt sheeting in my dads roof) in order for the foam to stick to the underside of the tiles or cement sheeting. Not sure on that though.
I wonder if the Thai companies use CFC liquids now, as they would be virtually fume free.?
I've lost my mind and I am making no effort to find it.
Yes, the photo on the below link looks as if indeed the chemicals are mixed at the spray head. This company is based in Pattaya but has offices in Bangkok and Issan. Pete
http://www.lohr-trade.com/
http://www.lohr-trade.com/
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- Khundon1975
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Could it be this one I wonder?
http://www.spraymepurfoam.com/index.php
Local office in Hua Hin.
17/29 Petkasem Rd. Soi 23
Bor-Fai
Hua Hin 77110
Tel.: 032 - 54.70.30
Fax: 032 - 54.75.13
http://www.spraymepurfoam.com/index.php
Local office in Hua Hin.
17/29 Petkasem Rd. Soi 23
Bor-Fai
Hua Hin 77110
Tel.: 032 - 54.70.30
Fax: 032 - 54.75.13
I've lost my mind and I am making no effort to find it.
If you go with the fibre option,minmum thickness should be 6inch, 10inch would be preferable.
I the uk the idea is to stop heat escaping through the roof,in los it works the other way,stops heat coming through the roof.
Unfortunately you wont have cavity walls which should also be insulated,with beads.
I can always insulate your roof for you,as its my job in the uk.
I the uk the idea is to stop heat escaping through the roof,in los it works the other way,stops heat coming through the roof.
Unfortunately you wont have cavity walls which should also be insulated,with beads.
I can always insulate your roof for you,as its my job in the uk.
- JimmyGreaves
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You using this as well as foil under the roof tiles, crazy?crazy88 wrote:I use this one. Seems to do what it says on the tin. ie I am siiting in the house with no aircon and I am not hot,outside is stifling. Anyone got any informed opinions on this versus the cheaper foil ?
Crazy 88
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