Ceiling insulation, recommended for staying cool?

[bankruatsteve]

With reference to insulation properties, materials are given an "R" value which is a relative resistance to thermal conduction.

[superal]

17 minutes ago, bankruatsteve said:

With reference to insulation properties, materials are given an "R" value which is a relative resistance to thermal conduction.

The higher the number the better the insulation or less conduction ?

[bankruatsteve]

1 hour ago, superal said:

The higher the number the better the insulation or less conduction ?

Better meaning more resistance, yes - R-20 has double the resistance than R-10.  A batt of R-10 with another batt of R-10 on top of it will have total R-20.

[Pedrogaz]

I bought the thickest most expensive insulation for my home. It did nothing. The house is still hot as hell especially on the second story and despite 5 metre ceilings. My aircon bill are outrageous. What is needed in my opinion, and we will be having work done soon is extractor fans in the attic space such that when the temperate climbs about say 27 degrees, the fans start to pull the warm air out of the attic. As I say, I will be having these installed in the next few months. I have avoided this solution for many years because our roofs don't leak, unlike the vast majority of Thai roofs, and I had the attitude that if it ain't broke, don't fix it. I'll let you know how/if it reduces air-con use.

[bankruatsteve]

1 minute ago, Pedrogaz said:

I bought the thickest most expensive insulation for my home. It did nothing. The house is still hot as hell especially on the second story and despite 5 metre ceilings. My aircon bill are outrageous. What is needed in my opinion, and we will be having work done soon is extractor fans in the attic space such that when the temperate climbs about say 27 degrees, the fans start to pull the warm air out of the attic. As I say, I will be having these installed in the next few months. I have avoided this solution for many years because our roofs don't leak, unlike the vast majority of Thai roofs, and I had the attitude that if it ain't broke, don't fix it. I'll let you know how/if it reduces air-con use.

That can help.  The main sources of heat invasion are conduction through walls (does the inside of your wall feel warm when the outside is in direct sun?), windows, glass doors, and leaky doors (or someone opening the door every few minutes.)  There are many ways to reduce the heat from these sources and commented in several threads this forum.

[geoffbezoz]

2 hours ago, emptypockets said:

I'm sure there will be one or two members who actually did that for the Egyptians and can confirm the prices too. 

Well there ancestors may be or else involved in making lots of money from it via the pyramid sales method ????

[holymoly]

Hello !    It's not only about the thickness of the ceiling insulation

but about proper ventilation in the roof space.  Of that builder here 

don't have a clue.  There should be several 'holes' under the sofit 

( air intake ) and one or or two holes on the top of roof ( air to go out ), both protected against rain.  You and Google figure the rest.

[Artisi]

41 minutes ago, Pedrogaz said:

I bought the thickest most expensive insulation for my home. It did nothing. The house is still hot as hell especially on the second story and despite 5 metre ceilings. My aircon bill are outrageous. What is needed in my opinion, and we will be having work done soon is extractor fans in the attic space such that when the temperate climbs about say 27 degrees, the fans start to pull the warm air out of the attic. As I say, I will be having these installed in the next few months. I have avoided this solution for many years because our roofs don't leak, unlike the vast majority of Thai roofs, and I had the attitude that if it ain't broke, don't fix it. I'll let you know how/if it reduces air-con use.

Better looking into that is under your roof, any insulation? If not, that is where to start. 

If you are to run fan/s in the roof space, they shouldn't be run until the roof space temp. is slightly higher than the outside ambient temp. 

Unfortunately house design in Thailand is hopeless, no thought is given to designing a "cool" - - - unfortunately it usually becomes a poor after the event fix-up. 

 

My home, even after extremely long periods of high day and overnight temps. is always 5 or more degrees below the outside temp. without a/c running. The reason being it was designed and built as  "cool" house without going over the top with design or materials. 

 

[spidermike007]

4 hours ago, superal said:

R-22 ? I am not conversant with that . Where did you buy it from and did electric cables pose a problem ? Your ceiling is suspended type ? What is the area or size approx of your attic please ?

Thanks for your help 

Bought from Global House. Cheap. 200 bt. for about a 2.5 square meter roll. About a 1500 SF attic. Yes, suspended. He just pick them up and laid the cables over the insulation. And cut to lay around the girders. Took him about six hours. Small, thin and nimble guy. Great worker. An electrician by trade but also a great handyman. Made a big difference. House is alot more comfortable now. Used to turn off bedroom AC in am and within two hours room was 92f. Now mid afternoon it to only 86f! 

[wgdanson]

Can I put this stuff OVER the rafters, ie leave a gap between it and the ceiling board please? Or does it have to be in contact with the ceiling?

Can I just place it end to end, the room is 6m long but the rolls are only 4m. Do I need to 'joint'it in any way?

 

[Soundspeed]

We had thick insulation in our home ceilings in Melbourne and it worked a treat both in cold and hot weather. We installed the aluminium cell type in our second floor ceiling here in Chiang mai and the people who installed it (from Homepro) also taped and fitted the panels carefully. The result was a 3 degree reduction in ambient room temperature in the whole house. The upper floor didn't become a 'hot box' because we managed the air flow allowing cool air in during the mornings and closing the doors and windows trapping it during the hot part of the day. Normally at about 10.00am.  Also having window coverings is vital.

 

Radiant heat is also absorbed through the exterior of your building so the more shade you can provide for the outside South and West walls via verandahs the better. We also found that the air conditioning was way more efficient than previously. Again of you keep the windows and doors shut and avoid sunlight streaming in through them.

Walk around the inside of your condo and feel the inside walls after sunset - you will get an idea where the most heat is coming from.

[Artisi]

46 minutes ago, wgdanson said:

Can I put this stuff OVER the rafters, ie leave a gap between it and the ceiling board please? Or does it have to be in contact with the ceiling?

Can I just place it end to end, the room is 6m long but the rolls are only 4m. Do I need to 'joint'it in any way?

 

1. Yes - gap is ok

2. No - butt the ends

Edited August 14, 2019 by Artisi

[wgdanson]

1 hour ago, Artisi said:

1. Yes - gap is ok

2. No - butt the ends

You mean put them close to each other, no gap, or some sort of 'glue'?

[DJ54]

The house is finished ...can the insulation be laid on top of ceiling and still be effective? 2 bedroom 2 bathrooms. One bedroom AC only rest of house no AC.

Edited August 14, 2019 by DJ54
Add

[carlyai]

@Superal said: 'I have considered the sprayed foam under the roof which would solve the leaks and give insulation but I think it is quite expensive . Any info from those who have used this method would be appreciated .'

We used the spray insulation for our house roof in Pattaya. The roof was just tiles with no heat barriers. It did make a great deal of difference, the rooms felt cooler. Also stops the thieves coming through the roof, as the roof tiles are very difficult to remove.

At the end of weeks of very hot days, when the heat daily overcomes all your heat protection barriers, and your fans are blowing around hot air, there's nothing like turning on the air conditioning.

Sent from my SM-J700F using Tapatalk

[fredge45]

21 hours ago, holymoly said:

Hello !    It's not only about the thickness of the ceiling insulation

but about proper ventilation in the roof space.  Of that builder here 

don't have a clue.  There should be several 'holes' under the sofit 

( air intake ) and one or or two holes on the top of roof ( air to go out ), both protected against rain.  You and Google figure the rest.

The ventilation of the attic space is critical.  Hot air rises yes?  Make sure there are adequate vents (with window screen to keep out insects) installed into the soffit.  Roof top vents to not have to spinning types as the rising air is just spinning them,  If there are gable areas they can be used very well for outlet vents.

[sometimewoodworker]

20 minutes ago, fredge45 said:

The ventilation of the attic space is critical.  Hot air rises yes?  Make sure there are adequate vents (with window screen to keep out insects) installed into the soffit.  Roof top vents to not have to spinning types as the rising air is just spinning them,  If there are gable areas they can be used very well for outlet vents.

Make sure you have mosquito protection with those vents