Thread: What roof to choose for new build?

Any fancy fooker also put sprinklers up on top of their alu-zinc roof to keep the place nice and Scandinavianish during hot seasons? I presume the painted alu-zinc sheets don't rust and any run off that doesn't evaporate goes into the guttering. Would make a diffo to the temp inside the house?

It's got a ridge down the middle so the sheets are approx 5.5m each side. Expansion shouldn't be an issue right?

I also believe that they cool down a lot faster once the sun goes down as they don't hold the heat like roof tiles do.


I've been wrong before.

Originally Posted by katie23

is there a guest room for me & my dog when the roof reno is done? Lol.

Only the master bedroom is good enough for you dear K-pop.

It's right near the mountains and lake too so easy for hiking and mountain biking. I'll clean me helmet.

Originally Posted by Edmond

I'll clean me helmet.

Remove the Eddo cheese inside of it!

Originally Posted by Edmond

I'm currently renovating a house in CM and will do the roof in the next few weeks. Have decided to go with alu-zinc sheeting instead of tiles which invariably end up being a headache at some point down the line with little leaks or cracks or shiz like that.

The main roof is 135sqm that will be done with 20mm, or is it 25mm of PU foam on the underside. I believe that the 5mm adhesive foil isn't really worth it as it separates and falls away.

The price is around 40k which is reasonable.

Is that 40k for roof+PU, or just the PU foam? All included I assume, and sounds very reasonable. Our roof came with 35mm PU, and cost us an extra 207 baht/sq.m. on top of the roofing price.

I also believe that they cool down a lot faster once the sun goes down as they don't hold the heat like roof tiles do.

I've been wrong before.

not this time !

Originally Posted by mikenot

Is that 40k for roof+PU, or just the PU foam? All included I assume, and sounds very reasonable. Our roof came with 35mm PU, and cost us an extra 207 baht/sq.m. on top of the roofing price.

Yes, I'm in the middle of an exercise sesh so a bit brain-fuzzy.

I believe it's around 140b sqm extra for the PU Foam, but don't recall the thickness right now. Think it's 20 or 25mm.

For the 135 sqm roof, 0.35 sheets, It's around 20k with no insulation, 27k-ish with crappy thin foil that will fall off, and around 40k with the PU Foam, iirc.

Regardless of what roof you decide on it will create unwanted heat, ceiling insulation is a must, I have 12" ! it does obviously help. I would plan on installing a fan (solar?) on gable end as high up as possible, suck out some of the hot air, the whirly things are about useless as they don't move enough air, but moving a decent volume of air will be a benefit, still will need AC when its as hot as it is now, but every little bit helps. When the air is cooler outside and the roof is heating from the sun noticeable difference with fan...

Originally Posted by mikenot

Is that 40k for roof+PU, or just the PU foam?

DD Metal Sheet roofing comes recommended by the contractors here, purchasing meself which means they're not making any profit from it. They've a few big manufacturing plants and lots of branded delivery trucks so not some fly by night bunch of Lulu-ers.

Anyway, just back from there for final consultations. 0.30mm painted brown with 25mm PU Foam with 12 meter ridge, 135sqm in total, plus screws, 39,180thb. Another 40k for dismantling the old roof tiles and installing the new sheets (beams are as solid as a wok), around 4 days work, quite a fair priced job really.

Originally Posted by Airportwo

I have 12"

You showboating muthafucka!

It's not the size, it's how you use it!!


Which is actually true with insulation. Tiz all about that r-value baby (as well as being installed properly). There are some thinner sheets that have a higher r-value than thicker sheets. We have r-37 6 inch batts in the villa iirc.

Originally Posted by katie23

The main roof is 135sqm that will be done with 20mm, or is it 25mm of PU foam on the underside.

We went with BlueScope ZACS steel roof fitted with 25 mm PU foam. Heavy thunderstorms don't intrude. ZACS is one step below Colorbond, which is the top of the line in metal roofing IMHO.

Now ya tellz me.

Aboot how much did ya pay per sqm if ya happen to remember?

The 0.30mm, painted + 25mm PU Foam comes to just under 300 per sqm at this large and well known manufacturer.

Originally Posted by Vettronics

I am about to build and we are not sure what roof material to use.

G'day Vet.
You can't go past BlueScope roofing. If you can afford it go for the top of the line ZincAlum / Colorbond with pre-fitted PU foam insulation. If that's a bit too pricey go for BlueScope ZACs. It will last about 30 years compared with Colorbond's 50+ years.
BlueScope have pretty high levels of QA accreditation for their stockists, but if you can, buy direct.
And don't forget to fully insulate the ceiling cavity with good quality 75 mm foil backed insulation

Originally Posted by Edmond

painted brown

G'day Edmond,
I'd go for a lighter colour if you can. White would be the best.
Our roof was included in the build price - we specified it to the builder so I don't have a separate cost for it. I do know ZincAlum / Colorbond was beyond our budget.
I'm wary of roofing manufacturers who offer low-cost painted steel roofing. Having seen the Bluescope manufacturing process up close, I can confirm they put a lot into maintaining their reputation for quality.

Originally Posted by peciacake

G'day Edmond,
I'd go for a lighter colour if you can. White would be the best.

G'day Cake-Mate,

Cheers. I was thinking that. Then I also started thinking that with 25mm of PU Foam and R37 ceiling insulation, and with most people presumably in the kitchen, dining room or living room 3 stories down during the day, and only in the top level bedrooms well after the sun has set, would having brown paint instead of white paint make any difference to the temp inside the house?

Educated answers welcome.

Originally Posted by Edmond

Educated answers welcome

I'm out, will leave it to the experts on thermal transfer.
Suffice to say the less work and AC unit has to do the lower the energy costs, so every bit helps. Particularly given how temps are increasing.

Three stories to the bedroom. Good on you mate - well done. My knees object to three stairs these days let alone three stories.

^

I doubt I'll ever be staying there, but will install a chair-master if I do.

Originally Posted by peciacake

I'd go for a lighter colour if you can. White would be the best.

From a place we stopped off at while driving past.



สีเขียวใบตอง - Banana leaf green on the top left caught the eye.....

^I'd also go for a light coloured roof, based on the words from others in this forum. I'm not an expert on thermal transfer either.

I'm partial to having a red roof (similar to the Mediterranean style houses) but since PH is a tropical country, my head is saying choose a light coloured roof.

^lots of colours for the roof! In PH, the common ones that I see (pre painted ones) are blue, green, red & cream/ off white.

From the pic above, I'd choose the last one on the right, 2nd row from top (off white) OR the one below it (kinda beige).

Originally Posted by Digby Fantona

My wife says that we are having tiles. She has many friends who have metal roofs on their properties and say that they are all sweat boxes. Our present house has a metal roof but the first floor ( British first floor ) is unused so, effectively, we have very high ceilings. Our new house will have high ceilings and tiles with insulation.

Your tiled roof looks good, Digby. As does your new house. Congratulations.

^ Hounded off the board by Lulu in 2018 and hasn't been back online since.

Originally Posted by katie23

From the pic above, I'd choose the last one on the right, 2nd row from top (off white) OR the one below it (kinda beige).

Funny you should say that, I asked about the cream one as a first choice and got a Mai mee. Not have.

Very unusual for a Thai vendor to show something that they don't have in stock.

^maybe go to another supplier and see if they have the roof colour that you're looking for?

Originally Posted by katie23

maybe go to another supplier

You've got great style and taste.

Pick you up at 10am with lunch and a waterfall trip then after. :-)

The colour of your roof is not going to make any difference 3 floors and 2 concrete slabs below. And once the sun sets a metal roof is going to radiate heat back out long before you go to bed.

Cheers, was thinking dat.

Originally Posted by mikenot

The colour of your roof is not going to make any difference 3 floors and 2 concrete slabs below

Hi Mike,
I'm not an expert but respectfully disagree.
The color of a roof can indeed make a difference in the temperature inside a three story building, especially in the tropics.
The impact of roof colour on temperature in rooms three floors below:
Light-colored roofs reflect more sunlight, reducing heat absorption. This helps keep the rooms below cooler by reducing excess heat from entering the building.
Dark-colored roofs absorb more heat from the sun, leading to higher temperatures inside the building. This results in rooms holding the heat. Think of the feeling of getting up in the morning and walking on the tiled floor - the tiles are warm as the building has stored the heat.
Regarding the rooms below, the impact of roof colour may be less significant compared to the upper rooms. However, rooms where walls are directly exposed to sunlight and a darker roof colour would combine to higher temperatures in those areas leading to transfer of heat through the structure.


As you say, a metal roof will radiate heat quickly once the sun sets. During the day, metal roofs absorb a significant amount of heat from the sun. If the roof cavity isn't insulated the heat is transferred into the rooms below. When the sun sets and the temperature drops, the metal roof will release this stored heat back into the atmosphere.


The color of the roof does influence the temperature inside the building, with darker colors leading to more heat absorption. Metal roofing, due to its properties, radiates heat back out after the sun sets, aiding in cooling the building.