WTK: Hurricane-proofing your roof

[The_Honourable]

Good day tuners,

Have plans in the new year to reinforce my roof from gusty winds, especially tropical storm and hurricane force winds. Would like recommendations for a professional roofing contractor or company to do this job.

Thanks!

[Duane 3NE 2NR]

What kind of roof do you have?

Most roof installers now put hurricane straps anyway

[toyolink]

What kind of roof do you have?

Most roof installers now put hurricane straps anyway

The roofers I see all over the place using under sized I-Beams and purlin with things like hurricane straps and expansion joints non-existent.
Today is about the lowest cost and looks.

[The_Honourable]

What kind of roof do you have?

Most roof installers now put hurricane straps anyway

Galvanized roof with the old school wooden rafters that has a criss cross ceiling design. The design was to install a grooved wooden ceiling which was popular back in the 80s.

So far the wooden rafters is still good and no need for a new roof at the moment. I'm guessing that I would need hurricane ties or straps?

[Rory Phoulorie]

What kind of roof do you have?

Most roof installers now put hurricane straps anyway

Galvanized roof with the old school wooden rafters that has a criss cross ceiling design. The design was to install a grooved wooden ceiling which was popular back in the 80s.

So far the wooden rafters is still good and no need for a new roof at the moment. I'm guessing that I would need hurricane ties or straps?

Are the wooden rafters appropriately sized for the spacing between them? If not hurricane straps are not going to do anything if the wind pressure on the roof snaps the rafter in two. Depending on the shape of the roof and the wind direction, while you may get uplift (suction) on one side, you could be getting a downward pressure on the next side.

You want to "hurricane proof" your roof in a cost effective manner? Get the TTBS Small Building Code and check your roof structure against what is recommended in the code. Then you would know what should be done. Don't rely on the advice alone from roofing contractors.

[The_Honourable]

What kind of roof do you have?

Most roof installers now put hurricane straps anyway

Galvanized roof with the old school wooden rafters that has a criss cross ceiling design. The design was to install a grooved wooden ceiling which was popular back in the 80s.

So far the wooden rafters is still good and no need for a new roof at the moment. I'm guessing that I would need hurricane ties or straps?

Are the wooden rafters appropriately sized for the spacing between them? If not hurricane straps are not going to do anything if the wind pressure on the roof snaps the rafter in two. Depending on the shape of the roof and the wind direction, while you may get uplift (suction) on one side, you could be getting a downward pressure on the next side.

You want to "hurricane proof" your roof in a cost effective manner? Get the TTBS Small Building Code and check your roof structure against what is recommended in the code. Then you would know what should be done. Don't rely on the advice alone from roofing contractors.

Thank you Rory, appreciate that information a lot. Hope to get someone who does follow the code.

[nervewrecker]

MY neighbors does use concrete blocks

[kevin310]

Put Simpson ties on each rafter, check screws on roof, change/ add more if it makes you feel comfortable. Does your home have a proper ring beam ? Im guessing you have a wooden wall plate that sits on the top of your walls.

[Chimera]

[aaron17]

Anybody offering a video drone services to see the top of the roof?

[Strugglerzinc]

What kind of roof do you have?

Most roof installers now put hurricane straps anyway

The roofers I see all over the place using under sized I-Beams and purlin with things like hurricane straps and expansion joints non-existent.
Today is about the lowest cost and looks.

Contractor installed my bro in law's purlins to the beam with 2 purlin screws at each point. He said drilling and bolts were long time ting.

[Ben_spanna]

The issue or the real weak point of a roof is the overhang or the eve, air must get under in order to lift it off, if your eves are long and extended like a majority of traditional rooves in the caribbbean therein lies your weak point.
Hurricanes are not like a tornado-it doesn’t suck upwards, the force of the winds from the sides get under your eve and create lift.
Just something to think about.

[adnj]

I believe that this was already coverered in the home building thread but...

A building's roof will typically attempt to lift out of position when the air moving across the roof surface smooths out and creates an area of lower air pressure above it relative to the air below it. This is similar to an airplane's wing moving through air.

"Hurricane Proofing" a roof includes:

- Minimizing the horizontal dimension of an eave to reduce lift.
- Avoiding shallow or low-pitch roofs. 8/12 or 9/12 pitch (about 35°) is optimal to reduce aerodynamic lift and roof rollover.
- Enhanced mechanical attachment to ringbeams and walls.
- Using discontinuous roof surfaces by adding dormers, porticoes, etc., to reduce aerodynamic lift.

Concentrating on mechanical attachment can work but the best solution is to design a roof that is much less likely to lift in the first place.

[screwbash]

no roof will witstand a hurricane. the sheeting will blow away and the steel remains. them room men just fooling.

[Rovin]

What kind of roof do you have?

Most roof installers now put hurricane straps anyway

The roofers I see all over the place using under sized I-Beams and purlin with things like hurricane straps and expansion joints non-existent.
Today is about the lowest cost and looks.

Contractor installed my bro in law's purlins to the beam with 2 purlin screws at each point. He said drilling and bolts were long time ting.

he hadda be a crazy ass man , a man who does not know better or knows better but do rel short cut work cause dise how typical trinis operate

have a next setta madd asss who does weld d purlin onto d L brackets on d I beam ....

[maj. tom]

It's true, not much can survive a Cat 5 unscathed except a purpose built dome or bunker. But Florida has building codes that helps mitigate the damage which includes the tie straps and a proper reinforced concrete foundation with masonry walls so that there is a direct structural link between the roof and the ground. I think our building codes would be close to that. That should hold up in a Cat 3. But expect the roof of the most securely built house to go in a Cat 5.

[adnj]

It's true, not much can survive a Cat 5 unscathed except a purpose built dome or bunker. But Florida has building codes that helps mitigate the damage which includes the tie straps and a proper reinforced concrete foundation with masonry walls so that there is a direct structural link between the roof and the ground. I think our building codes would be close to that. That should hold up in a Cat 3. But expect the roof of the most securely built house to go in a Cat 5.

Michael made landfall as a Category 5 hurricane. Recently built structures survived with little damage. These were elevated with very little reinforced concrete used. There waslittle to no roof damage, also.

Current building codes are a minimum. The are many existing methods and best practices that enhance Category 5 hurricane damage mitigation.

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