Ceiling Insulation

[tomster]

Hi,

 

I need to insulate a roof on a bar as cheaply as possible.

 

I'm not sure what the roof type is called, but it's very common here, this is what it looks like underneath:

 

 

When the sun is on it it's literally too hot to touch the underside and this heat is radiating down into the area below, making it crazy hot in the space.

 

I would rather deal with this with something from underneath as it would save the headache of working on it from above, weight issues etc.

 

Is there something I can stick or paint on the underside that would block a decent amount of the heat out, it doesn't need to be 100% effective, 80--90% would be good enough.

 

Thanks in advance.

[IvorBiggun2]

Take off the current roof and replace with insulated roof panels.

 

[tomster]

12 minutes ago, IvorBiggun2 said:

Take off the current roof and replace with insulated roof panels.

 

Sadly not possible, we need a solution that uses the existing roof panels.

[Muhendis]

What I would do would be to screw some thin plywood or cement board to the underside of those, what look like, 30mm x 30mm steel roof panel supports.

This would create an air gap which would reduce heat significantly. If you could also fill that air gap with fibreglass insulation, that would be even better.

 

[tomster]

4 minutes ago, Muhendis said:

What I would do would be to screw some thin plywood or cement board to the underside of those, what look like, 30mm x 30mm steel roof panel supports.

This would create an air gap which would reduce heat significantly. If you could also fill that air gap with fibreglass insulation, that would be even better.

 

Thanks - that seems like a good option.

 

https://www.thaiwatsadu.com/th/product/แผ่นยิปซัม-ชนิดทนไฟ-13-มม-GYPROC-ขนาด-120-x-240-ซม-60253095

 

How about using this stuff with some fibreglass insulation above it?

[Will B Good]

Similar problem.....I'm considering plastic lats on the underside with rolls of silvered insulation in between......also a sprinkler system on the roof as we have guttering.

[PJ71]

If this is an outside area under the roof i'd say anything you try in this heat is a waste of time.

[Muhendis]

10 minutes ago, tomster said:

Thanks - that seems like a good option.

 

https://www.thaiwatsadu.com/th/product/แผ่นยิปซัม-ชนิดทนไฟ-13-มม-GYPROC-ขนาด-120-x-240-ซม-60253095

 

How about using this stuff with some fibreglass insulation above it?

That's the sort of thing although it looks a bit thick and heavy.

Thaiwatsadu also have some 5mm thick plywood which might be better

[4MyEgo]

1 hour ago, tomster said:

I need to insulate a roof on a bar as cheaply as possible.

 

Whatever you try will be money washed down the drain, but as they say in Thailand, "up to you".

 

I studied roofing for years and the only way your going to reduce heat penetrating below your roof is to:

 

1. Put in a gable style roof

2. Put cement tiles on

3. Put in Thermal reflective sissolation under the tiles

4. Put in a gyprock ceiling with insulation batts above the gyprock ceiling.

5. Put in a couple of whirly birds

 

We have an external area of 80m2 with an iron roof above and a gyprock ceiling, it has two big whirly birds on the roof which extracts the heat already below it, i.e. it's an open area. I know that if I put insulation batts above the gyprock ceiling, it would reduce the heat from above, however as we never use the area apart from drying clothes, it would have been a waste of money, however the house has 1 to 5 above and remains cool throughout the day, with the air conditioner turned on at about 2 pm on days that hit 40 degree or thereabout.  

 

Trying to combat the heat on the cheap here is like trying to live here without an air conditioner.

 

Best of luck anyways.

 

 

[bunnydrops]

On the cheap, there is that roll insulation https://www.lazada.co.th/products/5mm-90cm-2m-insulation-aluminium-foil-i2606309418-s9329922897.html putting batts to hold it. Depending on the size, I have found that covering the top with shade cloth helps a lot ( has to be replaced every 1 or 2 years depending how bad the weather has been)

[Fruit Trader]

Be aware that the roof structure might not be up to adding much more load.

 

Reducing emissivity is very effective and might be a lightweight cheap solution if it can be made to look tidy. Material with shiny side facing into the room achieves this. 

 

 

 

[0ffshore360]

The aluminium foil works well but your problem would be to suspend it . If appearance is not important that could be achieved using wires, mesh or light wooden sheeting.

I used thin plywood and slid styrene sheets into the space created on a leanto roof at original house.

[Denim]

Try to find a lightweight Thai worker and get him to paint the roof Thais white on the outside. This will reflect a lot more of the suns heat.

 

If the bar is outside you are up against since the slightest breeze blows in the hot air.

[brianthainess]

46 minutes ago, Fruit Trader said:

Be aware that the roof structure might not be up to adding much more load.

 

Reducing emissivity is very effective and might be a lightweight cheap solution if it can be made to look tidy. Material with shiny side facing into the room achieves this. 

 

 

 

You can buy rolls of double sided silver, and lots and lots of contact adessive. OP I suggest a trip to Global House to see the options, I think I also saw one with interrogated wire.

 

[IvorBiggun2]

1 hour ago, 4MyEgo said:

Trying to combat the heat on the cheap here is like trying to live here without an air conditioner.

 

Words of wisdom.

[patman30]

"as cheaply as possible"
this should rule out buying new roof panels backed with insulation, and then have a plasterboard ceiling with more insulation

that leaves the hosepipe on the roof, this is your cheapest option and it is actually really effective
(i plan to soon add this to my kitchen roof permanently, after feeling how effective it was in a restaurant recently, we already throw a hosepipe sprinkler on the roof when its hot)
i would suggest HDPE pipe with a few sprinklers, the ones you just push into the pipe
if you can run this say 10am-6pm then great
but ideally you would create a loop but this would have additional costs obviously
but then you could use a lower power pump and not have to pay for all that water

2nd least expensive option will be put a gypsum ceiling up (could also add some nice lighting same time)
if you wanted to then
you could fill the gap in ceiling with anything you can get your hands on to act as insulation
bubble wrap, polystyrene etc instead of buying proper insulation
 

[patman30]

2 hours ago, tomster said:

Thanks - that seems like a good option.

 

https://www.thaiwatsadu.com/th/product/แผ่นยิปซัม-ชนิดทนไฟ-13-มม-GYPROC-ขนาด-120-x-240-ซม-60253095

 

How about using this stuff with some fibreglass insulation above it?

13mm is less commonly used for ceiling, although can be better, it costs more and weighs more
9mm is commonly used for ceilings as it is cheaper and lighter
this is what would be typically used for ceilings (same brand, less than half the price)
https://www.thaiwatsadu.com/th/product/ยิปซัมยิปรอค-ชนิดธรรมดา-ขอบเรียบ-(SE)-9-มม-GYPROC-ขนาด-120-x-240-ซม-60191572

 

or an even cheaper brand at 102 baht a sheet
https://www.thaiwatsadu.com/th/product/ยิปซัมชนิดธรรมดา-9-มม-ขอบลาดMAXUMขนาด-120-x-240-ซม-60375893

i doubt there would be any significant thermal difference between the different sheets if installed under that roof.

[sometimewoodworker]

4 hours ago, tomster said:

Hi,

 

I need to insulate a roof on a bar as cheaply as possible.

 

I'm not sure what the roof type is called, but it's very common here, this is what it looks like underneath:

 

 

When the sun is on it it's literally too hot to touch the underside and this heat is radiating down into the area below, making it crazy hot in the space.

 

I would rather deal with this with something from underneath as it would save the headache of working on it from above, weight issues etc.

 

Is there something I can stick or paint on the underside that would block a decent amount of the heat out, it doesn't need to be 100% effective, 80--90% would be good enough.

 

Thanks in advance.

Yes there is though you don’t stick it onto the roof. It is the radiant barrier film

i went from a roof that was over 60C

 

to one that was ambient temperature 37C

full story, including some who disagree vehemently that it could work. It does

https://www.coolthaihouse.com/forum/viewtopic.php?t=4476

[Luuk Chaai]

Most common insulation materials work by slowing conductive heat flow and -- to a lesser extent -- convective heat flow. Radiant barriers and reflective insulation systems work by reducing radiant heat gain. To be effective, the reflective surface must face an air space. Dust accumulation on the reflective surface will reduce its reflective capability. The radiant barrier should be installed in a manner to minimize dust accumulation on the reflective surface.

When installing a foil-type barrier, it's important to allow the material to "droop" between the attachment points to make at least a 1.0 inch (2.5 cm) air space between it and the bottom of the roof. 

and....... seeing as we are inThailand ....

Note that reflective foil will conduct electricity, so avoid making contact with bare electrical wiring. 

[rwill]

As mentioned above, you could put some sprinklers on top of the roof. 

[Nemises]

Rent these to your patrons. 

[YorkshireTyke]

19 hours ago, Denim said:

Try to find a lightweight Thai worker and get him to paint the roof Thais white on the outside. This will reflect a lot more of the suns heat.

 

If the bar is outside you are up against since the slightest breeze blows in the hot air.

 It's not any old white paint, it's actually called Sunblock, available in Home pro and quite effective for a few years.

[Gsxrnz]

Take a trip to the Hospital on 2nd Road Soi 4.  They have a huge glass (maybe perspex) exposed ceiling.  They have a water recirculating pump that cools the ceiling.  You could do it on the cheap with simple products purchased at Homepro or similar.  If I had to guess, you could probably do it for 10k or less with plastic pipe, a water tank, and a pump.

 

Running costs would be a bit of electrickery and whatever water evaporates. Bound to be far more efficient than any insulation methods.

[Muhendis]

21 hours ago, Muhendis said:

What I would do would be to screw some thin plywood or cement board to the underside of those, what look like, 30mm x 30mm steel roof panel supports.

This would create an air gap which would reduce heat significantly. If you could also fill that air gap with fibreglass insulation, that would be even better.

 

I'm going to backtrack on this a bit. 

The plywood is still a reasonable idea but, having gained some more knowledge I would supplement that with aluminium foil arranged to have free air on both sides.

I changed my idea because I read this:-

https://radiantbarrier.com/blogs/news/how-radiant-barrier-works-heat-gain-loss-in-buildings#:~:text=Most aluminum insulation has only,strikes its air-bound surfaces.

[CharlesHolzhauer]

21 hours ago, 4MyEgo said:

I studied roofing for years and the only way your going to reduce heat penetrating below your roof is to:

 

2. Put cement tiles on

Cement tiles to reduce heat penetration?

[IvorBiggun2]

8 minutes ago, CharlesHolzhauer said:

Cement tiles to reduce heat penetration?

Too heavy.

[charleskerins]

21 hours ago, 4MyEgo said:

 

Whatever you try will be money washed down the drain, but as they say in Thailand, "up to you".

 

I studied roofing for years and the only way your going to reduce heat penetrating below your roof is to:

 

1. Put in a gable style roof

2. Put cement tiles on

3. Put in Thermal reflective sissolation under the tiles

4. Put in a gyprock ceiling with insulation batts above the gyprock ceiling.

5. Put in a couple of whirly birds

 

We have an external area of 80m2 with an iron roof above and a gyprock ceiling, it has two big whirly birds on the roof which extracts the heat already below it, i.e. it's an open area. I know that if I put insulation batts above the gyprock ceiling, it would reduce the heat from above, however as we never use the area apart from drying clothes, it would have been a waste of money, however the house has 1 to 5 above and remains cool throughout the day, with the air conditioner turned on at about 2 pm on days that hit 40 degree or thereabout.  

 

Trying to combat the heat on the cheap here is like trying to live here without an air conditioner.

 

Best of luck anyways.

 

 

the purpose of the insulation in Thailand being to trap some of the heat?    So right about the AC!

[NorthernRyland]

21 hours ago, 4MyEgo said:

Trying to combat the heat on the cheap here is like trying to live here without an air conditioner.

 

I can think of restaurants that have low ceilings and metal roofs. Even if I like their food I simply can not eat there during most times of the year because it feels like an oven. If they spent a few thousand baht to put in some 1CM foam that would make just enough difference to survive with a  fan on you.

[CharlesHolzhauer]

13 minutes ago, IvorBiggun2 said:

Too heavy.

Weight or heaviness does not influence the penetration of heat.

[NorthernRyland]

21 minutes ago, IvorBiggun2 said:

Too heavy.

Yet very common. What's a better solution? I guess you can do foam insulation metal sheeting but that's kind of ugly if nothing else.