New roof on house - how much?

[Niltava]

Evening all,

 

We have a four floor townhouse in Bangkok that needs a roof replacement.

 

Our chang (who we regularly use and we are generally happy with) has told us the best option is to use a reinforced steel frame with steel sheeting and PU foam sheet underneath as insulation. The area to be covered would be 2 slopes, each 6m x 4.3m (see attached) so the total area would be 52 sq m.

 

He's quoting a total price of THB 160,000 (65k for materials and 95k for labour), indicating it would take 7 days and the main challenge will be getting the materials onto the top of the building.

 

The price seems higher than we were anticipating, but we never had to replace a roof before so I'd be grafetul for comments from those with more experience. Pictures of the current roof also included for info.

 

Thanks,

 

N

 

 

[KhunLA]

Labor seems a bit high, not sure about the roof panels.   Not understanding the difficulty of getting panes on the roof.   We used BlueScope rolled steel, and they are extremely light.

 

Use the thickest insulated ones, along with rolls of ceiling insulation (R+37/38) and the ceiling (dry wall/gypsum board) is cool as cucumber, on the hottest days.

[Thailand J]

Talk to SCG Homes.

My Pattaya house is in a mostly farang moo ban. SCG Homes installed my neighbors new roof over the new kitchen and also replaced the old roof over his patio. A big job done right.

 

[motdaeng]

if you'd like to hold onto your "chang", consider negotiating a lower price.

sometimes, it might be worth paying a bit more to ensure everyone is satisfied.

 

it's difficult to determine if the price is fair without more details about the project.

seven days seems (too) long, even if there are only 3-4 people working. of course,

the fact that the roof is on the fourth floor of a bangkok townhouse adds to the

complexity and likely the cost.

 

here are some details to clarify with you "chang" before accepting the offer:

sandwich panel specifications: this includes the quality, color, and thickness of the pu insulation.

reinforced steel frame: ask for clarification. i think he will only add some galvanized steel profiles.

is it including new guttering?

warranty for the entire project? warranty how long? disposal of the old material?

is it a fixed price/quotation for the entire project, no additional cost?

... etc.

 

[Mike Lister]

The price doesn't seem that far out of line TBH, it's not a massive roof but the price of labour wouldn't increase proportionally if the roof was twice the size.

 

I don't like the PU foam solution though, I don't rate PU foam as an insulator, unless it's very thick. A better solution might be spray on closed cell insulation.

[freeworld]

10 minutes ago, Mike Lister said:

I don't like the PU foam solution though, I don't rate PU foam as an insulator, unless it's very thick. A better solution might be spray on closed cell insulation

They all have pretty similar R values

 

https://learnmetrics.com/insulation-r-value-chart-per-inch/

[JBChiangRai]

You may get away with spraying PU Foam insulation under the existing roof, it stops leaks and holds the roof together as well as heat insulation. spray at least 3” of foam.

[freeworld]

Find a link to a roofing supplier in Thailand. The roof sheeting costs can be estimated from that for comparison.

 

https://zacsroof.nsbluescope.com/th/en/roof-calculator/

[SAFETY FIRST]

15 hours ago, Niltava said:

I'd be grafetul for comments 

Get it done soon, the wet season is coming.