Ceiling Insulation - Worth the cost?

[SOTIRIOS]

...against the heat or the cold...insulation must be installed....secured....and sealed properly to be effective...

...this usually requires one or more barriers to be installed as well...

...of course conductivity of the framework must also be considered...

...then there is also the consideration of an air gap that can be incorporated in the design...

...what boggles the mind is that after 100 years they still appear practically oblivious to any of this here...

[Naam]

Are you trying to keep the heat inside the house ?

Why are you using batts of insulation ?

Do as The Thais do, tall roof, long overhangs, vents along top of walls with screening to let heat out and to keep bugs and snakes out.

Tall roof to let heat out vents. Long overhangs for shading, and cooling.

Do as the locals do.

Look at the architecture in Thailand and think.

Most of Thai architecture is designed for the heat and the heavy rains AND then BEAUTIFUL Thai Style is added to it.

Talk to the locals, bring your phrase book and use hand gestures.

This is their climate and building standards.

-local standards do not include airconditioning. the opening post of this thread is "insulation in context with planned airconditioning".

-"beautiful Thai style" does not prevent Farang sweating and feeling uncomfortable.

-phrase book and hand gestures cannot be used to discuss laws of thermo-physics.

-Thai building standards do not necessarily match the demands of Farangs.

therefore case "local standards" closed

next!

Edited June 4, 2016 by Naam

[eyecatcher]

Is there any basis for the Thai opinion that "no need" insulation?

the only downside is the ignorance of Thai builders!

I think you are too gentle when using the word "ignorance"

One example.

Normally here in Thailand a roof is installed by two c-profiles welded together on top of the columns.

In my house I have a 20 cm concrete ring beam all around on top of the columns, and next two c-profiles welded together on top of that beam.

Recently I had a Thai builder and he said that was WRONG.

Maybe not wrong but unnecessary and a waste of money UNLESS your design specifically calls for an eaves ring beam.

Believe me, I am the first to call a halt on any Thai building ideas but as yet I have not seen any eaves sagging, deflection or even failures due to undersizing of steelwork.

So why did you incorporate a 20cm concrete eaves beam?

[BigT73]

i was involved in a reno not too long ago, top floor in a condo. I installed the bats and the difference was huge, I used to sweat walking into the condo like I was in a oven, after installation it just felt warm. The major difference is in the arvo when its at its hottest I use the ac for a hour or so and just stays cool for hours after I turn it off. My mitsubishi a/c is on 28 any lower its freezing in the room.

On a second note my advice do not take any advice from sales girls from any home depots, they virtually know nothing let alone basic english. When I installed the ceiling framing, I wanted to use proper hangers from the supplier as the thai method to me was a bit sloppy. Her words to me 'no need, in thailand we not do this' luckily the SCG sales rep happened to be there and he said in Thai (my misses translated) that thai builders were idiots. Lol kinda harsh but they were his words.

[Berty100]

Is there any basis for the Thai opinion that "no need" insulation?

the only downside is the ignorance of Thai builders!

I think you are too gentle when using the word "ignorance"

One example.

Normally here in Thailand a roof is installed by two c-profiles welded together on top of the columns.

In my house I have a 20 cm concrete ring beam all around on top of the columns, and next two c-profiles welded together on top of that beam.

Recently I had a Thai builder and he said that was WRONG.

Maybe not wrong but unnecessary and a waste of money UNLESS your design specifically calls for an eaves ring beam.

Believe me, I am the first to call a halt on any Thai building ideas but as yet I have not seen any eaves sagging, deflection or even failures due to undersizing of steelwork.

So why did you incorporate a 20cm concrete eaves beam?

The ring beam has nothing to do with enforcing the roof construction, it does enforce your concrete frame construction.

[ross163103]

I installed batts that were approx 100 mm thick with foil on top. Helped significantly but I noticed after approx 5-7 years that the batts have compressed down to about half thickness of what they were originally. I think this is from the high humility here. I'm sure they still are offering some reduction in heat but obviously not as much as when first installed.

[eyecatcher]

Is there any basis for the Thai opinion that "no need" insulation?

the only downside is the ignorance of Thai builders!

I think you are too gentle when using the word "ignorance"

One example.

Normally here in Thailand a roof is installed by two c-profiles welded together on top of the columns.

In my house I have a 20 cm concrete ring beam all around on top of the columns, and next two c-profiles welded together on top of that beam.

Recently I had a Thai builder and he said that was WRONG.

Maybe not wrong but unnecessary and a waste of money UNLESS your design specifically calls for an eaves ring beam.

Believe me, I am the first to call a halt on any Thai building ideas but as yet I have not seen any eaves sagging, deflection or even failures due to undersizing of steelwork.

So why did you incorporate a 20cm concrete eaves beam?

The ring beam has nothing to do with enforcing the roof construction, it does enforce your concrete frame construction.

No it doesnt....well ok yes it does in exactly the same way as steel is used.

There really is no need to use anything hefty at the top because the columns are all braced with block brick walls.

In the uk walls are simply braced with timber roof trusses....the corners are simple brick and block with no further reinforcing.

Anyway sorry we digress from the OP.

[bankruatsteve]

I installed batts that were approx 100 mm thick with foil on top. Helped significantly but I noticed after approx 5-7 years that the batts have compressed down to about half thickness of what they were originally. I think this is from the high humility here. I'm sure they still are offering some reduction in heat but obviously not as much as when first installed.

Any reduction in heat defense would be from the reflective part getting dirty. Again, the insulation does NOTHING except provide air gap.

[Berty100]

Is there any basis for the Thai opinion that "no need" insulation?

the only downside is the ignorance of Thai builders!

I think you are too gentle when using the word "ignorance"

One example.

Normally here in Thailand a roof is installed by two c-profiles welded together on top of the columns.

In my house I have a 20 cm concrete ring beam all around on top of the columns, and next two c-profiles welded together on top of that beam.

Recently I had a Thai builder and he said that was WRONG.

Maybe not wrong but unnecessary and a waste of money UNLESS your design specifically calls for an eaves ring beam.

Believe me, I am the first to call a halt on any Thai building ideas but as yet I have not seen any eaves sagging, deflection or even failures due to undersizing of steelwork.

So why did you incorporate a 20cm concrete eaves beam?

The ring beam has nothing to do with enforcing the roof construction, it does enforce your concrete frame construction.

No it doesnt....well ok yes it does in exactly the same way as steel is used.

There really is no need to use anything hefty at the top because the columns are all braced with block brick walls.

In the uk walls are simply braced with timber roof trusses....the corners are simple brick and block with no further reinforcing.

Anyway sorry we digress from the OP.

In the civilized world walls are built with load bearing bricks or blocks, not so in Thailand.

The only load bearing construction are the columns or beams. The expansion and contraction from steel is much bigger from steel than from concrete.

In a country like Thailand where temperatures on the same day can go from 30° to 14°, it may make those columns move a little, which develops the cracks between brick and column.

If you have a concrete ring beam on top you minimize that effect.

[The Deerhunter]

The laminated foil foam does not harbour vermin as much as fibreglass and has a higher energy rating. Yes get it but it can be a mixed blessing. It slows down heat coming in during the day but also slows it leaving at night.

[Berty100]

The laminated foil foam does not harbour vermin as much as fibreglass and has a higher energy rating. Yes get it but it can be a mixed blessing. It slows down heat coming in during the day but also slows it leaving at night.

When your house is properly insulated there is no need for heat to "leave" your house at night, as it would be at comfortable temperature already during the day.

[bankruatsteve]

The laminated foil foam does not harbour vermin as much as fibreglass and has a higher energy rating. Yes get it but it can be a mixed blessing. It slows down heat coming in during the day but also slows it leaving at night.

Interesting. But, I don't think I or anybody else has been talking about "laminated foil foam". What is the "higher energy rating"? I have been talking about reflective foil that has maybe 5cm of "insulation" mostly to provide air gap.

[bazza40]

Is there anyone in the Chiang Rai area who knows how to retrofit roof vents? I'm convinced our roof space is a mass of heated air.

Insulation definitely helps, provided the roof is adequately vented.

[Naam]

The laminated foil foam does not harbour vermin as much as fibreglass and has a higher energy rating. Yes get it but it can be a mixed blessing. It slows down heat coming in during the day but also slows it leaving at night.

When your house is properly insulated there is no need for heat to "leave" your house at night, as it would be at comfortable temperature already during the day.

[Simons3]

Totally agree with the majority here Insulation is a YES if you run AC... where the Thais get the idea "Not Need" is from homes that don't use Aircon, in those instances you want the house to cool down as quickly as possible in the evenings, and not retain heat, so insulation is a detractor in houses without AC.

For the rest of us that need AC, then you can never have too much insulation. and to that effect if your building a house from new its best to get windows that seal without drafts and look at using those light weight " autoclaved" building block which have a good insulation value.

Apart from that add some shadeon the south side of the house and you wont be causing power outages running your AC full bore all day

[Naam]

I installed batts that were approx 100 mm thick with foil on top. Helped significantly but I noticed after approx 5-7 years that the batts have compressed down to about half thickness of what they were originally. I think this is from the high humility here. I'm sure they still are offering some reduction in heat but obviously not as much as when first installed.

Any reduction in heat defense would be from the reflective part getting dirty. Again, the insulation does NOTHING except provide air gap.

take a look at something that proves you are wrong:

[F4UCorsair]

A whirlybird on the roof, taking the hot air from the ceiling cavity, will make a greater difference, and that's based on personal experience.

Reflective foil under the tiles and a whirlybird are a better combination than batts, imo, but batts will prevent cool air being transferred through the ceiling to the roof cavity, so provide some benefit.

Use a multi pronged approach, whirlybird, foil and batts, none of them will break the bank.

Edited June 4, 2016 by F4UCorsair

[kannot]

Are you trying to keep the heat inside the house ?

Why are you using batts of insulation ?

Do as The Thais do, tall roof, long overhangs, vents along top of walls with screening to let heat out and to keep bugs and snakes out.

Tall roof to let heat out vents. Long overhangs for shading, and cooling.

Do as the locals do.

Look at the architecture in Thailand and think.

Most of Thai architecture is designed for the heat and the heavy rains AND then BEAUTIFUL Thai Style is added to it.

Talk to the locals, bring your phrase book and use hand gestures.

This is their climate and building standards.

-local standards do not include airconditioning. the opening post of this thread is "insulation in context with planned airconditioning".

-"beautiful Thai style" does not prevent Farang sweating and feeling uncomfortable.

-phrase book and hand gestures cannot be used to discuss laws of thermo-physics.

-Thai building standards do not necessarily match the demands of Farangs.

therefore case "local standards" closed

next!

didnt the "local" standards just fall down in Koh Chang?

[Manassas]

A whirlybird on the roof, taking the hot air from the ceiling cavity, will make a greater difference, and that's based on personal experience.

Reflective foil under the tiles and a whirlybird are a better combination than batts, imo, but batts will prevent cool air being transferred through the ceiling to the roof cavity, so provide some benefit.

Use a multi pronged approach, whirlybird, foil and batts, none of them will break the bank.

Thanks to all the home builders sharing their experience. I'm not experienced in building, but just trying to use common sense. Have installed the aluminum sheeting under the tiles and that was cheap. Will also have passive vents in attic, but haven't seen a whirlybird in the stores. This is where the Thais say enough. But my thought is that ceiling insulation will keep the air con in and reduce cooling costs in the same way it keeps the heat in in cold climates. The combo of aluminum under the tiles to keep the heat out and fiberglass on the ceiling to keep the cool in seems to make sense. The stay cool isn't cheap but isn't prohibitive either. Also using roof overhangs and trees for shading seems a good idea.

Interesting the several comments that insulation slows cooling the house at night. But hopefully the air con will take care of that.

[Naam]

Are you trying to keep the heat inside the house ?

Why are you using batts of insulation ?

Do as The Thais do, tall roof, long overhangs, vents along top of walls with screening to let heat out and to keep bugs and snakes out.

Tall roof to let heat out vents. Long overhangs for shading, and cooling.

Do as the locals do.

Look at the architecture in Thailand and think.

Most of Thai architecture is designed for the heat and the heavy rains AND then BEAUTIFUL Thai Style is added to it.

Talk to the locals, bring your phrase book and use hand gestures.

This is their climate and building standards.

-local standards do not include airconditioning. the opening post of this thread is "insulation in context with planned airconditioning".

-"beautiful Thai style" does not prevent Farang sweating and feeling uncomfortable.

-phrase book and hand gestures cannot be used to discuss laws of thermo-physics.

-Thai building standards do not necessarily match the demands of Farangs.

therefore case "local standards" closed

next!

didnt the "local" standards just fall down in Koh Chang?

indeed, they did!

http://www.nationmultimedia.com/national/Woman-killed-in-hotel-building-collapse-on-Koh-Cha-30287396.html

[fredge45]

A whirlybird on the roof, taking the hot air from the ceiling cavity, will make a greater difference, and that's based on personal experience.

Reflective foil under the tiles and a whirlybird are a better combination than batts, imo, but batts will prevent cool air being transferred through the ceiling to the roof cavity, so provide some benefit.

Use a multi pronged approach, whirlybird, foil and batts, none of them will break the bank.

Am constantly amazed seeing no ventilation of attic spaces being ventilated at all. That seems to be such a no-brainer but...

[Richard Hillis]

You need to prevent radiated heat from enteing your home.

The largest selling domestic insulation material in the world is cellulose fibre, it simply works better and lasts longer than any other material if manufactured to correct standards

If available and Installed correctly with no gaps to

a minimum 2.5 thermal resistance you would get the best results, also contrary to common belief radiated heat does not heat up the air in your home it heats up the surrounding objects throwing heat of those objects....You need to eliminate radiated heat from entering your home.

[bazza40]

Going a bit off topic, a local entrepreneur was selling motor scooter aluminized cloth seat covers. Alas, the Thais thought they were too expensive at 300 baht.

When mine wore out, I had a local tailor make up some more in silver cloth.

Black scooter seats absorb a lot of heat, especially when parked in the sun. It's amazing the difference the reflective covers make to my personal comfort on the scooter.

I went from grilled testicles and backside to almost tolerable.

[Richard Hillis]

A whirlybird on the roof, taking the hot air from the ceiling cavity, will make a greater difference, and that's based on personal experience.

Reflective foil under the tiles and a whirlybird are a better combination than batts, imo, but batts will prevent cool air being transferred through the ceiling to the roof cavity, so provide some benefit.

Use a multi pronged approach, whirlybird, foil and batts, none of them will break the bank.

Am constantly amazed seeing no ventilation of attic spaces being ventilated at all. That seems to be such a no-brainer but...

You are not trying to eliminate hot air from your roof cavity, you need to have a barrier to stop radiated heat whirly birds will not get rid of radiated heat. Extensively used in factories and buildings without ceiling cavities their main purpose is for ventilation.

[bazza40]

You need to prevent radiated heat from enteing your home.

The largest selling domestic insulation material in the world is cellulose fibre, it simply works better and lasts longer than any other material if manufactured to correct standards

If available and Installed correctly with no gaps to

a minimum 2.5 thermal resistance you would get the best results, also contrary to common belief radiated heat does not heat up the air in your home it heats up the surrounding objects throwing heat of those objects....You need to eliminate radiated heat from entering your home.

Cellulose fibre is a serious fire risk. It is normally treated with the cheapest fire retardant, boric acid, so it is very cost competitive with fibreglass. A lot of it is simply blown into the ceiling instead of being laid down as a blanket, so it is hit or miss whether it covers electrical components such as junction boxes.

Unfortunately, over time the combination of heat and humidity in a roof space causes the boric acid to slowly evaporate from the cellulose. Eventually, there is no fire retardant capacity left.

Cheap and widely used, yes. However, IMHO it is an unacceptable fire risk.

[fredge45]

A whirlybird on the roof, taking the hot air from the ceiling cavity, will make a greater difference, and that's based on personal experience.

Reflective foil under the tiles and a whirlybird are a better combination than batts, imo, but batts will prevent cool air being transferred through the ceiling to the roof cavity, so provide some benefit.

Use a multi pronged approach, whirlybird, foil and batts, none of them will break the bank.

Am constantly amazed seeing no ventilation of attic spaces being ventilated at all. That seems to be such a no-brainer but...

You are not trying to eliminate hot air from your roof cavity, you need to have a barrier to stop radiated heat whirly birds will not get rid of radiated heat. Extensively used in factories and buildings without ceiling cavities their main purpose is for ventilation.

Hot air is hot air and needs to be allowed to escape from the ceiling cavity. Ambient temperature air can enter the ceiling cavity by screened openings in the eaves... you can't get the temp lower than the outside air temp of course. The cooler air entering will become heated by the radiated heat and them dissipate via the roof vents (whirlybirds or passive vents).

[chiang mai]

You need to do several things at the same time for attic cooling to be effective, the first and foremost one is to vent the attic, install gable or ridge vents and then introduce vented soffits to provide a source of inbound cooler air from the lower levels. You need a LOT of ventilation and there are simple calculators available online to help estimate how much in and how much out (which need to be the same amount).

Second thing to do is to install a radiant barrier to deflect radiated heat from the roof tiles, away from the living space roof or walls - if one is not already installed in your house one can be retroffited but it's a bitch.

Third thing is to install bat insulation to protect against convected heat, R37 is useful - I have installed twice that amount..

Note: all those measures combined will protect against an outside temperature of say 36 degrees but they will probably fail when the temperature reaches 42 degrees plus.

[sandyf]

A whirlybird on the roof, taking the hot air from the ceiling cavity, will make a greater difference, and that's based on personal experience.

Reflective foil under the tiles and a whirlybird are a better combination than batts, imo, but batts will prevent cool air being transferred through the ceiling to the roof cavity, so provide some benefit.

Use a multi pronged approach, whirlybird, foil and batts, none of them will break the bank.

Am constantly amazed seeing no ventilation of attic spaces being ventilated at all. That seems to be such a no-brainer but...

You are not trying to eliminate hot air from your roof cavity, you need to have a barrier to stop radiated heat whirly birds will not get rid of radiated heat. Extensively used in factories and buildings without ceiling cavities their main purpose is for ventilation.

Hot air is hot air and needs to be allowed to escape from the ceiling cavity. Ambient temperature air can enter the ceiling cavity by screened openings in the eaves... you can't get the temp lower than the outside air temp of course. The cooler air entering will become heated by the radiated heat and them dissipate via the roof vents (whirlybirds or passive vents).

You are perfectly correct. Many get mixed up between 'ventilation' and 'convection'. Convection has been used as an insulation medium for hundreds of years. Hot air will leave of its own accord if replacement air is available, the replacement air will remove heat from surrounding materials as it passes through the cavity.

At one time I used to design large industrial ovens and in many instances used natural convection as a heat barrier.

[chiang mai]

One of the heat problems you probably can't solve, especially if the house doesn't have a radiant barrier between the roof tiles and the steel in the roof, is the conducted heat transfer of heat from the roof tiles, to the steel in the roof, to the walls below, it can be a significant problem evidenced by hot walls near the ceiling, in late after noon. Think of the steel in your roof as being the same as a heating element in your kettle, unless you can find a way to break that transfer your living space will get warm because it can't be insulated against.

[grin]

I don't see any suggestion of applying a reflective roof coating as has been mentioned on other threads. Seems like doing this this might be an easier alternative to retrofitting foil under the roof tiles. Not sure how effective a reflective coating would be in addition to the foil.

In our house we installed heavy duty fans at the top of both gables that have 3 way switches, off, on, or connected to a thermostat.

One thing I've noticed about having insulation is that whenever we have workers doing something in the attic that requires moving the insulation around they pay little attention to putting it back correctly. I.e. after an electrician, a cable guy or AC guy has been up there I need to go up and fix the insulation.

Grin