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jojogumabew

Hi All,

 

We're about to pour concrete on our second floor (metal deck structure) on our house. We're planning to use a steel roof and after spending a lot of time researching and going one way or the other, I am back to square one on roof insulation. This is what I've seen that's available here:

 

1) Closed cell foam spray insulation - Expensive but supposedly better because reduces heat transfer through convection. I had originally decided on this, but have read forums saying spray foam emits odors which takes ages to dissipate and if not mixed well smells bad. For ex. 

 

http://www.greenbuildingadvisor.com/community/forum/green-products-and-materials/14537/out-gassing-bad-stuff-spray-foam-insulation

 

Also the fireproofing chemicals they add in are supposedly not good for you.

 

2) Rockwool - Proven, reasonably priced but is an irritant if you breathe in.

 

Am now leaning towards this if I can figure out how to seal it in so the fibers can't fall out.

 

Please help!

 

THanks

 

 

 

 

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This info May or may not help you, however it Will give you more knowledge!!   Advances are being made on the insulation front quite rapidly, most are applicable and introduced into First world coun

Exactly.   Design it right and it doesn't need aircon.   Here are my ideas for an airconless house. - Raised off the ground - Verandah all round so that the house recieves as little direct sunli

I definitely suggest whatever you do to at lest run wiring for at least one attic fan in the roof peak.  You can get a nice fan that is temperature activated to run the heat out if you want or just ha

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towboat72

ive been trying to find this info also .

 

want to talk to wombat about what and how he did his restaurant roof ,it looks nice and seems to work well

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ed villas

 

2) Rockwool - Proven, reasonably priced but is an irritant if you breathe in.

 

dont. what will happen when (if) the roof leaks or "starts develop " small pin size hole.

 best bet is to use the "installation" w/metal(silver) backing. place it right up against the ROOF(inside of course)

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Headshot

Mandaue Foam has roll foam insulation (in various thicknesses) and also there is a business on Plaridel (I believe it is called Styrodek...or something like that) that has sheet and roll foam insulation. Neither of these products has any smell problems.

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jojogumabew

 

2) Rockwool - Proven, reasonably priced but is an irritant if you breathe in.

 

dont. what will happen when (if) the roof leaks or "starts develop " small pin size hole.

 best bet is to use the "installation" w/metal(silver) backing. place it right up against the ROOF(inside of course)

 

Do you mean the rockwool with foil backing is ok? Or still not ok? Would appreciate a link to the product so I can study it. Thanks!

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ed villas

since I cant PM you, try ace /true value.

near mega mall is the home depot/wil con near medical arts hospital.

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cebubird

 

2) Rockwool - Proven, reasonably priced but is an irritant if you breathe in.

 

dont. what will happen when (if) the roof leaks or "starts develop " small pin size hole.

 best bet is to use the "installation" w/metal(silver) backing. place it right up against the ROOF(inside of course)

Don't know if this is "best" or not, but that is what we are going to use. Engineer initially was going to use 5mm, and I had him change it to 8mm, double sided. 2750per roll and our roof needs 5 rolls. Also using the white galva/steel roofing with 2 thick coats of Boysen Laguna white roof guard.

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Canuck Joe

Our metal roof is rusting from the bottom on the overlaps and its only 12 years old. I think the overlaps should be caulked. I want to replace it with a roof top patio. Gutters only last 5 years

Mactan sea air is harsh.

Edited by Canuck Joe
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RogerDat

Greetings! Metal roof materal here is trash for the most part. My galvaloom roff has rust after 4 months!

Paint the roof with car paint, edxpensive, but will not fade for more than 20 years.

Back to main topic. I put roll alumin insulation under my roof. It is great, like having a big tree over the house. It supposedily adds R 9 to and subsiquent insulation on the ceiling under it. Must have 2 in air space on down side. Single, or doubble is fine, single alumium face down.

I uses the doubble foil with bubble between, it is strionger and easeyer to install. Use tie wire to attach to brackelia. I also use it in walls where their will be no air con. Air con areas have solid foam in them that is self extengushing.

It is R2 I think, not R19 as seller claims. The radiant heat blocker is what it is, not the latent heat that air has.

Phone # 344-6260

It cost P2500 for 1+ meter x 50 meter roll.

 

The spray foam copany I talked to that used to be in Cebu Home and Builders in Mandaue quated me P700,000 for 150 SM house! NO REFRENCES so i guess no suckers here to pay their start up cost!

 

 


post-7667-0-04267000-1359882693_thumb.jpgpost-7667-0-56116000-1359882722_thumb.jpg

Edited by RogerDat
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for what it's worth...

 

http://www.coolmetalroofing.org/elements/uploads/news/tmi_casestudy_13.pdf

 

 

...research shows that the single most effective way to cut the cooling loads from a hot-climate roof is to make the roof reflective. There’s a reason all those quaint little cottages in Bermuda have white roofs — they work.

 

and from the same source:

 

http://www.fsec.ucf.edu/en/publications/html/FSEC-CR-1220-00/index.htm

 

"Comparative Evaluation of the Impact of Roofing Systems on Residential Cooling Energy Demand in Florida"

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This info May or may not help you, however it Will give you more knowledge!!

 

Advances are being made on the insulation front quite rapidly, most are applicable and introduced into First world countries which are often in colds climates. Insulation will work both ways ie keeping cold out or warm out, think of a cool box for reference to the tropical climate we live in.


Probably one of the first was polystyrene sheets in varying thickness or densities. However early products were prone to degradation from heat and attack from vermin who love to make nests from the balls! Still in use but more modern forms are higher spec.

 

Rock wool or glass fibre came along ages ago, is available in foil backed, water vapour backed, loose packed, condensed, rolls, sheets etc. Profile thickness can be from 40mm up to 250mm. Its cheap, but has several drawbacks. Among the major are “saggage when used in vertical or angled positions, methods of fixation, but most of all, attack by critters! Mice, lizards and all such like absolutely love living in the stuff. They nibble the fibres, make tunnels and form nests in it. Literally within weeks.

 

I have pulled up 30 yr old floors that were insulated only to find the paper backing left in place, great piles of mouse shit and bundles of fibre in corners! The worst one was a ceiling I insulated then went back to put in a Velux about 3 weeks later. When I cut the plasterboard ceiling away, not only did I get a piece of board, but two mice fell out onto me! A nice little tunnel network was in evidence!


Next up was single sided foil backed foam. Foam for insulation, foil for reflection. However the foam used is pitifully thin. Advantage is ease of use and thin profile.


Then came bubble wrap in double thickness, with foil on both sides. (AIRFLEX) 10mm profile, supposedly equivalent to 100 mm rockwool. Double sided foil keeps out external heat source while retaining internal heat source.

 

Most recently has been advances in “Multi composite” insulations. These are several layers of foil and polyester fibres sewn together. Same principles as Airflex but better thermal qualities. Layering can be from 5 to 60 layers (Superfoil  SF 19, 40, 60). Critters don’t like munching ali or polyester fibres. 


As with all things, price is directly related to quality. SF 60 was what I was putting into my watermill in France, do it once, do it proper!


Location is a big factor, if in a modern city, glass fibre will last a lot longer than if used in a rural environment due to rodent population.

 

Proper installation is critical for any insulation, remember this well. Fixings that penetrate the insulation or gaps left in difficult corners will provide very efficient “thermal bridges”. Also remember the “Thermos flask” effect. Try to achieve a minimum of 40mm air gap each side of your insulation and finishes. This means 40mm gap between steel roof sheet and insulation, then another 40 between insulation and internal finish. Don’t forget to provide adequate ventilation of the internal air void also. 

 

I have yet to build my house here in the PI, but effective insulation will most definitely be used, not only in the roof, but walls also.


Really try and investigate your options, but possibly also spend some time considering passive cooling methods to integrate into your build now while still possible.

 

I do hope that this helps, but then again, maybe not!!

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2) Rockwool - Proven, reasonably priced but is an irritant if you breathe in.

 

dont. what will happen when (if) the roof leaks or "starts develop " small pin size hole.

 best bet is to use the "installation" w/metal(silver) backing. place it right up against the ROOF(inside of course)

rockwool is supposed to be fairly unaffected by water compared to the fibregalss stuff

 

and in europe they put a lof of fibreglass outside the concrete of office blocks where it is only protected by the "decorative" cladding which doesnt look 100% waterproof.

 

trouble is once cladding gets wet, it doesnt prevent heat escape very well, but im not sure thats so much of a problem when you try and keep the heat out.

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This info May or may not help you, however it Will give you more knowledge!!

 

Advances are being made on the insulation front quite rapidly, most are applicable and introduced into First world countries which are often in colds climates. Insulation will work both ways ie keeping cold out or warm out, think of a cool box for reference to the tropical climate we live in.

Probably one of the first was polystyrene sheets in varying thickness or densities. However early products were prone to degradation from heat and attack from vermin who love to make nests from the balls! Still in use but more modern forms are higher spec.

 

Rock wool or glass fibre came along ages ago, is available in foil backed, water vapour backed, loose packed, condensed, rolls, sheets etc. Profile thickness can be from 40mm up to 250mm. Its cheap, but has several drawbacks. Among the major are “saggage when used in vertical or angled positions, methods of fixation, but most of all, attack by critters! Mice, lizards and all such like absolutely love living in the stuff. They nibble the fibres, make tunnels and form nests in it. Literally within weeks.

 

I have pulled up 30 yr old floors that were insulated only to find the paper backing left in place, great piles of mouse shit and bundles of fibre in corners! The worst one was a ceiling I insulated then went back to put in a Velux about 3 weeks later. When I cut the plasterboard ceiling away, not only did I get a piece of board, but two mice fell out onto me! A nice little tunnel network was in evidence!

Next up was single sided foil backed foam. Foam for insulation, foil for reflection. However the foam used is pitifully thin. Advantage is ease of use and thin profile.

Then came bubble wrap in double thickness, with foil on both sides. (AIRFLEX) 10mm profile, supposedly equivalent to 100 mm rockwool. Double sided foil keeps out external heat source while retaining internal heat source.

 

Most recently has been advances in “Multi composite” insulations. These are several layers of foil and polyester fibres sewn together. Same principles as Airflex but better thermal qualities. Layering can be from 5 to 60 layers (Superfoil  SF 19, 40, 60). Critters don’t like munching ali or polyester fibres. 

As with all things, price is directly related to quality. SF 60 was what I was putting into my watermill in France, do it once, do it proper!

Location is a big factor, if in a modern city, glass fibre will last a lot longer than if used in a rural environment due to rodent population.

 

Proper installation is critical for any insulation, remember this well. Fixings that penetrate the insulation or gaps left in difficult corners will provide very efficient “thermal bridges”. Also remember the “Thermos flask” effect. Try to achieve a minimum of 40mm air gap each side of your insulation and finishes. This means 40mm gap between steel roof sheet and insulation, then another 40 between insulation and internal finish. Don’t forget to provide adequate ventilation of the internal air void also. 

 

I have yet to build my house here in the PI, but effective insulation will most definitely be used, not only in the roof, but walls also.

Really try and investigate your options, but possibly also spend some time considering passive cooling methods to integrate into your build now while still possible.

 

I do hope that this helps, but then again, maybe not!!

Interesting what you say but

 

about 3 years ago i spent a lot of time (quite time in the office :-) )on UK "green forums" for building.

 

the liveliest topics seemed to be does the multi layer insulation work?  some say its a scam while others say its super. I think the end result was yes, but you have to be a lot more careful to have an "airtight" building

 

but i have no direct experience, other than stickking free samples on the wall behind central heating radiators.

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SkyMan

I definitely suggest whatever you do to at lest run wiring for at least one attic fan in the roof peak.  You can get a nice fan that is temperature activated to run the heat out if you want or just have a switch you use from in the house.

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A couple of pics showing the "thermos flask" type installation, ie an air gap each side of the chosen installation medium.

post-13865-0-92985400-1359890066_thumb.jpgpost-13865-0-98457800-1359890090_thumb.jpg

In the top pic you can see the gap between inside face of wall and insulation,also, like in the bottom pic, the air gap is achieved by fixing the insulation to the underside of the roof rafters. In both you see the 40mm thick batten to space the plasterboard off the room side face of the insulation. In the top pic you can just make out some fitted plasterboard on the wall (vertical face)..

Edited by Tinbum
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